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1

Environment, Renewable Energy and Reduced Carbon Emissions  

NASA Technical Reports Server (NTRS)

Increased energy security and reduced carbon emissions pose significant challenges for science and technology. However, they also create substantial opportunities for innovative research and development. In this review paper, we highlight some of the key opportunities and mention public policies that are needed to enable the efforts and to maximize the probability of their success. Climate is among the uttermost nonlinear behaviors found around us. As recent studies showed the possible effect of cosmic rays on the Earth's climate, we investigate how complex interactions between the planet and its environment can be responsible for climate anomalies.

Sen, S.; Khazanov, G.; Kishimoto, Y.

2011-01-01

2

Can reducing black carbon emissions counteract global warming?  

SciTech Connect

Field measurements and model results have recently shown that aerosols may have important climatic impacts. One line of inquiry has investigated whether reducing climate-warming soot or black carbon aerosol emissions can form a viable component of mitigating global warming. Black carbon is produced by poor combustion, from our example hard coal cooking fires for and industrial pulverized coal boilers. The authors review and acknowledge scientific arguments against considering aerosols and greenhouse gases in a common framework, including the differences in the physical mechanisms of climate change and relevant time scales. It is argued that such a joint consideration is consistent with the language of the United Nations Framework Convention on Climate Change. Results from published climate-modeling studies are synthesized to obtain a global warming potential for black carbon relative to that of CO{sub 2} (680 on a 100 year basis). This calculation enables a discussion of cost-effectiveness for mitigating the largest sources of black carbon. It is found that many emission reductions are either expensive or difficult to enact when compared with greenhouse gases, particularly in Annex I countries. Finally, a role for black carbon in climate mitigation strategies is proposed that is consistent with the apparently conflicting arguments raised during the discussion. Addressing these emissions is a promising way to reduce climatic interference primarily for nations that have not yet agreed to address greenhouse gas emissions and provides the potential for a parallel climate agreement. 31 refs., 3 figs., 1 tab.

Tami C. Bond; Haolin Sun [University of Illinois at Urbana-Champaign, Urbana, IL (US)

2005-08-15

3

In Brief: Reducing black carbon emissions could immediately reduce global temperature increases  

NASA Astrophysics Data System (ADS)

A new assessment by the United Nations Environment Programme (UNEP) shows that measures to reduce emissions of black carbon, or soot, which is produced through burning of wood and other biofuels as well as by some industrial processes, could improve public health and help to significantly reduce projected global temperature increases. The Integrated Assessment of Black Carbon and Tropospheric Ozone highlights how specific measures targeting black carbon and other emissions from fossil fuel extraction, residential wood-burning cooking, diesel vehicles, waste management, agriculture, and small industries could affect climate. Full implementation of a variety of measures to reduce black carbon and methane emissions could reduce future global warming by about 0.5C, the assessment found. Reducing black carbon could have substantial benefits in the Arctic, the Himalayas, and other snow-covered regions because black carbon that settles on top of snow absorbs heat, speeding melting of snow and ice. Black carbon emission reductions would affect global temperatures more quickly than carbon dioxide emission reductions. Furthermore, reducing black carbon emissions would improve public health in the regions that emit large amounts of the harmful air pollutant.

Tretkoff, Ernie

2011-03-01

4

Exercise based transportation reduces oil consumption and carbon emissions  

NASA Astrophysics Data System (ADS)

Current abuse and misrepresentation of science hinders society's ability to address climate change. Scientific abuse results, in part, from a widespread perception that curbing emissions will require substantial economic, political, or personal sacrifice. Here I provide one example to illustrate that this perception is false. Simply walking or biking the amount recommended for a healthy lifestyle could reduce carbon emissions up to 11 percent if the distances traveled were substituted for car travel. This level of exercise is also sufficient to eliminate obese and overweight conditions in a few years without draconian diet plans. A reduction in carbon dioxide emissions of roughly 35 percent is possible if the revenue saved through decreased health care spending on obesity is redirected toward carbon abatement. This emissions reduction far exceeds that required by the Kyoto Protocol at no net cost. Finally, widespread substitution of driving with distances traveled during recommended daily exercise would considerably ease societal dependence on oil, which leads not only to climate change but also to air pollution, political and economic instability and habitat degradation. Thus, exercise based transportation constitutes a potentially favorable alternative to the energy and diet plans that are currently under consideration and a substantial step toward dealing with the threat of climate change.

Higgins, P. A.

2004-12-01

5

Institute a modest carbon tax to reduce carbon emissions, finance clean energy technology development, cut taxes, and reduce the deficit  

SciTech Connect

The nation should institute a modest carbon tax in order to help clean up the economy and stabilize the nations finances. Specifically, Congress and the president should implement a $20 per ton, steadily increasing carbon excise fee that would discourage carbon dioxide emissions while shifting taxation onto pollution, financing energy efficiency (EE) and clean technology development, and providing opportunities to cut taxes or reduce the deficit. The net effect of these policies would be to curb harmful carbon emissions, improve the nations balance sheet, and stimulate job-creation and economic renewal.

Muro, Mark; Rothwell, Jonathan

2012-11-15

6

Designing A Carbon Tax to Reduce U.S. Greenhouse Gas Emissions  

Microsoft Academic Search

This article describes a revenue and distributionally neutral approach to reducing U.S. greenhouse gas emissions that uses a carbon tax. The revenue from the carbon tax is used to finance an environmental earned income tax credit designed to be distributionally neutral. The credit is linked to earned income and helps offset the regressivity of the carbon tax. The carbon tax

Gilbert E. Metcalf

2008-01-01

7

A SECOND-BEST EVALUATION OF EIGHT POLICY INSTRUMENTS TO REDUCE CARBON EMISSIONS. (R825313)  

EPA Science Inventory

Abstract This paper uses a numerical general equilibrium model to compare the costs of alternative policies for reducing carbon emissions in a second-best setting with a distortionary tax on labor. We examine a carbon tax, two energy taxes, and both narrow-based and br...

8

Reducing Fossil Carbon Emissions and Building Environmental Awareness at  

E-print Network

on the biophysical environment in the following ways: · Reducing the amount of fossil fuels that are consumed. · Reducing the amount of pollution that is generated from fossil fuel consumption. · Reducing the amount of waste that is created when extracting and consuming fossil fuels. · Reducing Dartmouth College's demand

9

Global disparity in the ecological benefits of reducing carbon emissions for coral reefs  

NASA Astrophysics Data System (ADS)

Even if carbon emissions are reduced drastically in the next decade the amount of carbon already stored in the atmosphere would lead to the occurrence of extreme thermal events every three to four years between 2040 and 2080. This time lag on the effect of reducing emissions suggests that the benefits of carbon emission reduction on the health of coral reefs will be noticeable only in the long term. Here, we use a spatially explicit ecosystem model to compare the potential ecosystem benefits that Caribbean and Pacific reefs could gain from reductions in carbon emissions, and the timescale of these benefits. We found that whereas the effect of a reduction in emissions on Caribbean reefs will be modest and realized only in the long term (more than 60 years), Pacific reefs would start to show benefits within the first half of this century. Moreover, it seems that Pacific reefs have the potential to maintain their ecological integrity and ecosystem state in the mid- to long term if carbon emissions are reduced, but only if plate-like corals are present.

Ortiz, Juan Carlos; Bozec, Yves-Marie; Wolff, Nicholas H.; Doropoulos, Christopher; Mumby, Peter J.

2014-12-01

10

Reducing the uncertainties in carbon emissions fromReducing the uncertainties in carbon emissions from tropical deforestation -the BIOMASS mission  

E-print Network

from tropical deforestation - the BIOMASS mission Shaun Quegan University of Sheffield) Deforestation Fossil fuel release 6.4 Gt C yr-1 Deforestation 1.6 Gt C yr-1? Ocean uptake 2.2 Gt C yr-1 6.4 Gt C North of 30°; elsewhere, sources match sinks. #12;Calculating deforestation emissions 1Calculating

11

Incorporation of catalytic dehydrogenation into fischer-tropsch synthesis to significantly reduce carbon dioxide emissions  

DOEpatents

A new method of producing liquid transportation fuels from coal and other hydrocarbons that significantly reduces carbon dioxide emissions by combining Fischer-Tropsch synthesis with catalytic dehydrogenation is claimed. Catalytic dehydrogenation (CDH) of the gaseous products (C1-C4) of Fischer-Tropsch synthesis (FTS) can produce large quantities of hydrogen while converting the carbon to multi-walled carbon nanotubes (MWCNT). Incorporation of CDH into a FTS-CDH plant converting coal to liquid fuels can eliminate all or most of the CO.sub.2 emissions from the water-gas shift (WGS) reaction that is currently used to elevate the H.sub.2 level of coal-derived syngas for FTS. Additionally, the FTS-CDH process saves large amounts of water used by the WGS reaction and produces a valuable by-product, MWCNT.

Huffman, Gerald P.

2012-11-13

12

Cost effectiveness of bio-ethanol to reduce carbon dioxide emissions in Greece  

Microsoft Academic Search

The purpose of this study is to evaluate ethanol cost- effectiveness with regards to carbon dioxide emissions. Actually, bio-fuel production is only viable thanks to the tax credit policy resulting in economic deadweight loss. The environmental performance is assessed under the Life Cycle Assessment (LCA) framework. Economic burden to society to support the activity divided by avoided CO2 equivalent emissions

Stelios Rozakis; A. Natsis; M. Borzecka-Walker; K. Mizak

2011-01-01

13

Strategies for reducing carbon emissions on the tropical rain forest: The case of the Brazilian Amazon  

Microsoft Academic Search

The Brazilian Amazon deforestation has been responsible, in part, for the increasing concentrations of CO2 in the atmosphere. In 1990, the amount of carbon released to the atmosphere (as CO2) from Brazilian Amazon deforestation was 3.5 % to 4.9 % and 250 % to 360 % of the World and Brazilian annual emission from fossil fuels, respectively. In fact, the

Marcos A. V. de Freitas; Luiz. P. Rosa

1996-01-01

14

Biofuels from crop residue can reduce soil carbon and increase CO2 emissions  

NASA Astrophysics Data System (ADS)

Removal of corn residue for biofuels can decrease soil organic carbon (SOC; refs , ) and increase CO2 emissions because residue C in biofuels is oxidized to CO2 at a faster rate than when added to soil. Net CO2 emissions from residue removal are not adequately characterized in biofuel life cycle assessment (LCA; refs , , ). Here we used a model to estimate CO2 emissions from corn residue removal across the US Corn Belt at 580 million geospatial cells. To test the SOC model, we compared estimated daily CO2 emissions from corn residue and soil with CO2 emissions measured using eddy covariance, with 12% average error over nine years. The model estimated residue removal of 6 Mg per ha-1 yr-1 over five to ten years could decrease regional net SOC by an average of 0.47-0.66 Mg C ha-1 yr-1. These emissions add an average of 50-70 g CO2 per megajoule of biofuel (range 30-90) and are insensitive to the fraction of residue removed. Unless lost C is replaced, life cycle emissions will probably exceed the US legislative mandate of 60% reduction in greenhouse gas (GHG) emissions compared with gasoline.

Liska, Adam J.; Yang, Haishun; Milner, Maribeth; Goddard, Steve; Blanco-Canqui, Humberto; Pelton, Matthew P.; Fang, Xiao X.; Zhu, Haitao; Suyker, Andrew E.

2014-05-01

15

Nitrogen and phosphorous limitation reduces the effects of land use change on land carbon uptake or emission  

NASA Astrophysics Data System (ADS)

We used an Earth System Model that includes both nitrogen (N) and phosphorus (P) cycling to simulate the impacts of land-use and land-cover change (LULCC) for two representative concentration pathways (RCPs): a reforestation scenario (RCP4.5) and a deforestation scenario (RCP8.5). For each RCP, we performed simulations with and without LULCC using the carbon (C only) mode or including the full C, N and P cycles (CNP). We show, for the first time, that inclusion of N and P cycling reduces both the carbon uptake from reforestation in RCP4.5 and the carbon emission from deforestation in RCP8.5. Specifically, carbon-nutrient interaction reduces carbon uptake in RCP4.5 from 55 Pg C (C only) to 21 Pg C (CNP), or the emissions in RCP8.5 from 72 Pg C (C only) to 56 Pg C (CNP). Most of those reductions result from much weaker responses of net primary production to CO2 fertilization and climate change when carbon-nutrient interaction is taken into account, as compared to C only simulations. Our results highlight the importance of including nutrient-carbon interaction in estimating the carbon benefit from reforestation and carbon loss from deforestation in a future world with higher CO2 and a warmer climate. Because of the stronger nutrient limitation, carbon gain from reforestation in the temperate and boreal regions is much less than the carbon loss from deforestation in the subtropical and tropical regions from 2006 to 2100 for the two RCPs. Therefore protecting the existing subtropical and tropical forests is about twice as effective as planting new forests in the temperate and boreal regions for climate mitigation.

Wang, Ying-Ping; Zhang, Qian; Pitman, Andrew J.; Dai, Yongjiu

2015-01-01

16

Carbon offsets as a cost containment instrument : a case study of reducing emissions from deforestation and forest degradation  

E-print Network

Carbon offset is one type of flexibility mechanism in greenhouse gas emission trading schemes that helps nations meet their emission commitments at lower costs. Carbon offsets take advantage of lower abatement cost ...

Kim, Jieun, S.M. Massachusetts Institute of Technology

2010-01-01

17

Household actions can provide a behavioral wedge to rapidly reduce US carbon emissions  

PubMed Central

Most climate change policy attention has been addressed to long-term options, such as inducing new, low-carbon energy technologies and creating cap-and-trade regimes for emissions. We use a behavioral approach to examine the reasonably achievable potential for near-term reductions by altered adoption and use of available technologies in US homes and nonbusiness travel. We estimate the plasticity of 17 household action types in 5 behaviorally distinct categories by use of data on the most effective documented interventions that do not involve new regulatory measures. These interventions vary by type of action and typically combine several policy tools and strong social marketing. National implementation could save an estimated 123 million metric tons of carbon per year in year 10, which is 20% of household direct emissions or 7.4% of US national emissions, with little or no reduction in household well-being. The potential of household action deserves increased policy attention. Future analyses of this potential should incorporate behavioral as well as economic and engineering elements. PMID:19858494

Dietz, Thomas; Gardner, Gerald T.; Gilligan, Jonathan; Stern, Paul C.; Vandenbergh, Michael P.

2009-01-01

18

To reduce its carbon emissions, a Vermont college draws on the power of cows  

NSDL National Science Digital Library

Green Mountain Becomes First Campus Powered by Vermont Dairy Cowshttp://www.greenmtn.edu/gmcjournal/pop_102306_cow_power.aspLocal farm leading way for green powerhttp://www.addisonindependent.com/?q=node/295CVPS Cow Power [Macromedia Flash Player]http://www.cvps.com/cowpower/Cow%20Power%20home.htmlThe Ashden Awards for Sustainable Energyhttp://www.ashdenawards.org/Vermont is a state that is known for its passion in developing alternative farming methods and independence in its political thought. Now it can lay claim to another important recent development in its long history. As of this week, Green Mountain College in the town of Poultney is believed to be the first college in the United States that will be powered by cows. To be accurate, however, it should be noted that the energy that will be shipped to Green Mountain via the Central Vermont Public Serviceâs âCow Powerâ program. Power will be created from burning biogas created from cow manure. Initially, the college will derive approximately fifty percent of its energy needs for the main campus from this new energy source. It is estimated that this will allow the college to reduce its carbon emissions by approximately 3500 metric tons per year. Thereâs a great deal of interest in this program, and the schoolâs provost, Bill Throop recently commented that âWe want our students learning how to support sustainable communities right here in Vermont and this helps us lead by example.â The first link will take visitors to a CNN news article on this recent development in creating a sustainable energy source on the campus of Green Mountain College. Moving along, the second link leads to a press release from the Green Mountain College Journal which provides some nice details on this new initiative. The third link leads to an article from this Mondayâs Addison Independent, which reports on the efforts of the Foster Brothers Farm in Middlebury, Vermont to create a new company that will allow them to sell electricity produced, on farms across the United States. The fourth link will take users to a very fun and informative site provided by the Central Vermont Public Service which explains the niceties of their âCow Powerâ program, and also includes a great segment on âHow Energy Happensâ. The last and final link leads to the homepage of The Ashden Awards for Sustainable Energy. Here, visitors can learn about these rather interesting awards, which honor organizations that have made commitments to developing practical sustainable energy technologies.

Grinnell, Max

2006-01-01

19

Biodiversity losses and carbon emissions in Amazon region - the situation of contemporary period and strategies for reduce these environmental changes  

SciTech Connect

The forest removal is a major contributor to local, regional and global environmental changes. Many of the tropical`s species are gravely threatened Numerous studies suggest that from 1970 to 1990 between 5 and 20 percent of the tropical`s species were committed to extinction. In 1995, the deforested lands in Brazilian Amazon account an amount Superior to 470,000 Km{sup 2}, old deforestation included, for a total surface of tropical`s rain forest of 3.4 and 3.8 million square kilometres. In 1990`s, the amount of carbon released to the atmosphere (as CO{sub 2}) from Brazilian Amazon deforestation was 3.5 % to 4.9 % and 250 % to 360 % of the World and Brazilian annual emission from fossil fuels, respectively. On the other hand, if deforestation is stopped and replaced with a rational forest management, a reuse of degraded lands for agro-forestry and biomass production for energy and industrial purposes, we can reduce the pressure on forests lands and the net carbon flux will be reversed. In this paper, we discuss the relations with biodiversity losses and carbon emissions in Brazilian Amazon region in the last thirty years and find suggest the principal`s strategies to reduce this environmental`s destruction.

Freitas, M.A.V. de; Aquino, L.C.; Rosa, L.P.

1997-12-31

20

Strategies for reducing carbon emissions on the tropical rain forest: The case of the Brazilian Amazon  

SciTech Connect

Forests systems are renewable resources that can be used by present generations and that should be available to future generations if they are exploited on a sustainable basis. The tropical forest is still an immense and unknown field. The issues are: What means a sustainable basis in the tropical rain forests? What are the means of harmonising an economic development with an environmental equilibrium in tropical regions? One way to meet this requirement is to analyse the potentially {open_quotes}no regrets{close_quotes} options on which it is possible to agree upon despite controversies about what will be the true long run costs and benefits of various courses of actions. In the case of the Brazilian Amazon, in the last thirty years, the use of biomass and land has increased rapidly. Therefore, environmental and social problems have emerged with some intensity and have had repercussions on local and global scales. In relation to the recent global environmental changes, the Brazilian Amazon is considered as a key region for biodiversity conservation and preserving a carbon sink. In this paper, the main methodological option is to conceive a set of {open_quotes}no-regret{close_quotes} options, related with the land uses and biomass valorisation, which are analysed through the same framework. The options considered here are: decrease of the great cattle ranching and of the predatory timber extraction; the increase of forest management (harvest of timber and nontimber extractive products) and forest plantations in the degraded lands. The aims to focus on three elements: job creation, technico-economic adequation and environmental impacts, with special regards concerning the limitation of the atmospheric emissions of greenhouse gases (carbon flow).

Freitas, M.A.V. de; Rosa, L.P.

1995-11-01

21

Subsidence and carbon loss in drained tropical peatlands: reducing uncertainty and implications for CO2 emission reduction options  

NASA Astrophysics Data System (ADS)

Conversion of tropical peatlands to agriculture leads to a release of carbon from previously stable, long-term storage, resulting in land subsidence that can be a surrogate measure of CO2 emissions to the atmosphere. We present an analysis of recent large-scale subsidence monitoring studies in Acacia and oil palm plantations on peatland in SE Asia, and compare the findings with previous studies. Subsidence in the first 5 years after drainage was found to be 142 cm, of which 75 cm occurred in the first year. After 5 years, the subsidence rate in both plantation types, at average water table depths of 0.7 m, remained constant at around 5 cm yr-1. Bulk density profiles indicate that consolidation contributes only 7 % to total subsidence, in the first year after drainage, and that the role of compaction is also reduced quickly and becomes negligible after 5 years. Over 18 years after drainage, 92 % of cumulative subsidence was caused by peat oxidation. The average rate of carbon loss over the first 5 years was 178 t ha-1 yr-1 CO2eq, which reduced to 73 t ha-1 yr-1 CO2eq over subsequent years, resulting in an average loss of 100 t ha-1 yr-1 CO2eq annualized over 25 years. Part of the observed range in subsidence and carbon loss values is explained by differences in water table depth, but vegetation cover and addition of fertilizers also influence peat oxidation. A relationship with groundwater table depth shows that subsidence and carbon loss are still considerable even at the highest water table levels theoretically possible in plantations. This implies that improved water management will reduce these impacts by only 20 % at most, relative to current conditions, and that high rates of carbon loss and land subsidence should be accepted as inevitable consequences of conversion of forested tropical peatlands to other land uses.

Hooijer, A.; Page, S.; Jauhiainen, J.; Lee, W. A.; Lu, X. X.; Idris, A.; Anshari, G.

2011-09-01

22

CARBON DIOXIDE EMISSION REDUCTION  

E-print Network

CARBON DIOXIDE EMISSION REDUCTION TECHNOLOGIES AND MEASURES IN US INDUSTRIAL SECTOR FINAL REPORT TO KOREA ENVIRONMENT INSTITUTE FEBRUARY 2007 #12;B #12;C CARBON DIOXIDE EMISSION REDUCTION TECHNOLOGIES.5 Primary Energy Use and Carbon Dioxide Emissions for Selected US Chemical Subsectors in 1994

Delaware, University of

23

Rules to Cut Carbon Emissions Also Reduce Other Air Pollutants A first-of-its-kind study released today by scientists at Syracuse and  

E-print Network

Rules to Cut Carbon Emissions Also Reduce Other Air Pollutants A first-of-its-kind study released emissions from power plants would provide an added bonus--reductions in other air pollutants that can make air pollutants across the continental United States. The authors of the new study, Co

Mather, Patrick T.

24

Speaker to Address Impact of Natural Gas Production on Greenhouse Gas Emissions When used for power generation, Marcellus Shale natural gas can significantly reduce carbon  

E-print Network

generation, Marcellus Shale natural gas can significantly reduce carbon dioxide emissions, but questions have been raised whether development of shale gas resources results in an overall lower greenhouse gas, "Life Cycle Greenhouse Gas Emissions of Marcellus Shale Gas," appeared in Environmental Research Letters

Boyer, Elizabeth W.

25

Using Vehicle Taxes to Reduce Carbon Dioxide Emissions Rates of New Passenger Vehicles: Evidence from France, Germany, and Sweden  

E-print Network

France, Germany, and Sweden link vehicle taxes to the carbon dioxide (CO2) emissions rates of passenger vehicles. Based on new vehicle registration data from 20052010, a vehicles tax is negatively correlated with its ...

Klier, Thomas

26

Energy Prices, Taxes and Carbon Dioxide Emissions  

Microsoft Academic Search

Taxes levied on the carbon content of fuels (carbon taxes) are being considered in many OECD countries as a possible policy instrument to reduce carbon dioxide emissions. This paper first reviews the policy response in Member countries to the threat of global warming. It then discusses the link between carbon emission intensities and current energy prices, touching also on the

Peter Hoeller; Markku Wallin

1991-01-01

27

Potential for Woody Bioenergy Crops Grown on Marginal Lands in the US Midwest to Reduce Carbon Emissions  

NASA Astrophysics Data System (ADS)

While cellulosic biofuels are widely considered to be a low carbon energy source for the future, a comprehensive assessment of the environmental sustainability of existing and future biofuel systems is needed to assess their utility in meeting US energy and food needs without exacerbating environmental harm. To assess the carbon emission reduction potential of cellulosic biofuels, we need to identify lands that are initially not storing large quantities of carbon in soil and vegetation but are capable of producing abundant biomass with limited management inputs, and accurately model forest production rates and associated input requirements. Here we present modeled results for carbon emission reduction potential and cellulosic ethanol production of woody bioenergy crops replacing existing native prairie vegetation grown on marginal lands in the US Midwest. Marginal lands are selected based on soil properties describing use limitation, and are extracted from the SSURGO (Soil Survey Geographic) database. Yield estimates for existing native prairie vegetation on marginal lands modeled using the process-based field-scale model EPIC (Environmental Policy Integrated Climate) amount to ~ 6.72.0 Mg ha-1. To model woody bioenergy crops, the individual-based terrestrial ecosystem model ED (Ecosystem Demography) is initialized with the soil organic carbon stocks estimated at the end of the EPIC simulation. Four woody bioenergy crops: willow, southern pine, eucalyptus and poplar are parameterized in ED. Sensitivity analysis of model parameters and drivers is conducted to explore the range of carbon emission reduction possible with variation in woody bioenergy crop types, spatial and temporal resolution. We hypothesize that growing cellulosic crops on these marginal lands can provide significant water quality, biodiversity and GHG emissions mitigation benefits, without accruing additional carbon costs from the displacement of food and feed production.

Sahajpal, R.; Hurtt, G. C.; Fisk, J. P.; Izaurralde, R. C.; Zhang, X.

2012-12-01

28

MOBILISING RURAL HOUSEHOLDS TO STORE CARBON, REDUCE HARMFUL EMISSIONS AND IMPROVE SOIL FERTILITY;INTRODUCTION OF THIRD GENERATION STOVES  

Microsoft Academic Search

Commercialization of a high-efficiency household stove, which burns crop and forest waste as part of a clean, carbon capturing & storing household energy programme, to be implemented with local reforestation initiative. This paper introduces the concept of mobilising rural households in developing countries to help alleviate the impacts of climate change through a reduction of emissions from inefficient biomass burning

Robert Flanagan; Stephen Joseph

29

Influence of reduced carbon emissions and oxidation on the distribution of atmospheric CO2: Implications for inversion analyses  

Microsoft Academic Search

Recent inverse analyses constraining carbon fluxes using atmospheric CO2 observations have assumed that the CO2 source from atmospheric oxidation of reduced carbon is released at the surface rather than distributed globally in the atmosphere. This produces a bias in the estimates of surface fluxes. We used a three-dimensional (3D) atmospheric chemistry model (GEOS-CHEM) to evaluate the magnitude of this effect

Parvadha Suntharalingam; James T. Randerson; Nir Krakauer; Jennifer A. Logan; Daniel J. Jacob

2005-01-01

30

Carbon Dioxide Emission Estimates  

NSDL National Science Digital Library

The Carbon Dioxide Information Analysis Center of the Oak Ridge National Laboratory provides this new data on carbon dioxide emissions from fossil fuel burning, hydraulic cement production, and gas flaring in 1995. Data for one degree grid cells can be downloaded from the site in addition to code for analysis of the data.

31

Australian climatecarbon cycle feedback reduced by soil black carbon  

E-print Network

LETTERS Australian climate­carbon cycle feedback reduced by soil black carbon JOHANNES LEHMANN1 Annual emissions of carbon dioxide from soil organic carbon are an order of magnitude greater than all anthropogenic carbon dioxide emissions taken together1 . Global warming is likely to increase the decomposition

Lehmann, Johannes

32

Role of lignin in reducing life-cycle carbon emissions, water use, and cost for United States cellulosic biofuels.  

PubMed

Cellulosic ethanol can achieve estimated greenhouse gas (GHG) emission reductions greater than 80% relative to gasoline, largely as a result of the combustion of lignin for process heat and electricity in biorefineries. Most studies assume lignin is combusted onsite, but exporting lignin to be cofired at coal power plants has the potential to substantially reduce biorefinery capital costs. We assess the life-cycle GHG emissions, water use, and capital costs associated with four representative biorefinery test cases. Each case is evaluated in the context of a U.S. national scenario in which corn stover, wheat straw, and Miscanthus are converted to 1.4 EJ (60 billion liters) of ethanol annually. Life-cycle GHG emissions range from 4.7 to 61 g CO2e/MJ of ethanol (compared with ? 95 g CO2e/MJ of gasoline), depending on biorefinery configurations and marginal electricity sources. Exporting lignin can achieve GHG emission reductions comparable to onsite combustion in some cases, reduce life-cycle water consumption by up to 40%, and reduce combined heat and power-related capital costs by up to 63%. However, nearly 50% of current U.S. coal-fired power generating capacity is expected to be retired by 2050, which will limit the capacity for lignin cofiring and may double transportation distances between biorefineries and coal power plants. PMID:24988448

Scown, Corinne D; Gokhale, Amit A; Willems, Paul A; Horvath, Arpad; McKone, Thomas E

2014-08-01

33

Forest carbon response to management scenarios intended to mitigate GHG emissions and reduce fire impacts in the US West Coast region  

NASA Astrophysics Data System (ADS)

US West coast forests are among the most carbon dense biomes in the world and the potential for biomass accumulation in mesic coastal forests is the highest recorded (Waring and Franklin 1979, Hudiburg et al. 2009). Greenhouse gas (GHG) mitigation strategies have recently expanded to include forest woody biomass as bioenergy, with the expectation that this will also reduce forest mortality. We examined forest carbon response and life cycle assessment (LCA) of net carbon emissions following varying combinations of bioenergy management scenarios in Pacific Northwest forests for the period from 2010-2100. We use the NCAR CLM4 model combined with a regional atmospheric forcing dataset and account for future environmental change using the IPCC RCP4.5 and RCP 8.5 scenarios. Bioenergy management strategies include a repeated thinning harvest, a repeated clearcut harvest, and a single salvage harvest in areas with projected insect-related mortality. None of the bioenergy management scenarios reduce net emissions to the atmosphere compared to continued business-as-usual harvest (BAU) by the end of the 21st century. Forest regrowth and reduced fire emissions are not large enough to balance the wood removals from harvest. Moreover, the substitution of wood for fossil fuel energy and products is not large enough to offset the wood losses through decomposition and combustion. However, in some ecoregions (Blue Mountains and East Cascades), emissions from the thinning harvests begin to improve over BAU at the end of the century and could lead to net reductions in those ecoregions over a longer time period (> 100 years). For salvage logging, there is no change compared to BAU emissions by the end of the 21st century because the treatment area is minimal compared to the other treatments and only performed once. These results suggest that managing forests for carbon sequestration will need to include a variety of approaches accounting for forest baseline conditions and in some ecoregions, harvest reductions below current levels will sequester more carbon than additional harvest removals for bioenergy. References: Hudiburg, T., B. E. Law, D. P. Turner, J. Campbell, D. Donato, and M. Duane. 2009. Carbon dynamics of Oregon and Northern California forests and potential land-based carbon storage. Ecological Applications 19:163-180. Waring, R. H., and J. F. Franklin. 1979. Evergreen Coniferous Forests of the Pacific Northwest. Science 204:1380-1386.

Hudiburg, T. W.; Law, B. E.; Thornton, P. E.; Luyssaert, S.

2012-12-01

34

Applications of Carbon Dioxide Capture and Storage Technologies in Reducing Emissions from Fossil-fired Power Plants  

Microsoft Academic Search

The aim of this paper is to investigate the global contribution of carbon capture and storage technologies to mitigating climate change. Carbon capture and storage is a technology that comprises the separation of from carbon dioxide industrial- and energy-related sources, transport to a storage location (e.g., saline aquifers and depleted hydrocarbon fields), and long-term isolation from the atmosphere. The carbon

M. Balat; H. Balat; C. z

2009-01-01

35

Carbon Emission Flow in Networks  

PubMed Central

As the human population increases and production expands, energy demand and anthropogenic carbon emission rates have been growing rapidly, and the need to decrease carbon emission levels has drawn increasing attention. The link between energy production and consumption has required the large-scale transport of energy within energy transmission networks. Within this energy flow, there is a virtual circulation of carbon emissions. To understand this circulation and account for the relationship between energy consumption and carbon emissions, this paper introduces the concept of carbon emission flow in networks and establishes a method to calculate carbon emission flow in networks. Using an actual analysis of China's energy pattern, the authors discuss the significance of this new concept, not only as a feasible approach but also as an innovative theoretical perspective. PMID:22761988

Kang, Chongqing; Zhou, Tianrui; Chen, Qixin; Xu, Qianyao; Xia, Qing; Ji, Zhen

2012-01-01

36

Reducing carbon dioxide to products  

DOEpatents

A method reducing carbon dioxide to one or more products may include steps (A) to (C). Step (A) may bubble said carbon dioxide into a solution of an electrolyte and a catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce said carbon dioxide into said products. Step (B) may adjust one or more of (a) a cathode material, (b) a surface morphology of said cathode, (c) said electrolyte, (d) a manner in which said carbon dioxide is bubbled, (e), a pH level of said solution, and (f) an electrical potential of said divided electrochemical cell, to vary at least one of (i) which of said products is produced and (ii) a faradaic yield of said products. Step (C) may separate said products from said solution.

Cole, Emily Barton; Sivasankar, Narayanappa; Parajuli, Rishi; Keets, Kate A

2014-09-30

37

Large Scale U.S. Unconventional Fuels Production and the Role of Carbon Dioxide Capture and Storage Technologies in Reducing Their Greenhouse Gas Emissions  

SciTech Connect

This paper examines the role that carbon dioxide capture and storage technologies could play in reducing greenhouse gas emissions if a significant unconventional fuels industry were to develop within the United States. Specifically, the paper examines the potential emergence of a large scale domestic unconventional fuels industry based on oil shale and coal-to-liquids (CTL) technologies. For both of these domestic heavy hydrocarbon resources, this paper models the growth of domestic production to a capacity of 3 MMB/d by 2050. For the oil shale production case, we model large scale deployment of an in-situ retorting process applied to the Eocene Green River formation of Colorado, Utah, and Wyoming where approximately 75% of the high grade oil shale resources within the United States lies. For the CTL case, we examine a more geographically dispersed coal-based unconventional fuel industry. This paper examines the performance of these industries under two hypothetical climate policies and concludes that even with the wide scale availability of cost effective carbon dioxide capture and storage technologies, these unconventional fuels production industries would be responsible for significant increases in CO2 emissions to the atmosphere. The oil shale production facilities required to produce 3MMB/d would result in net emissions to the atmosphere of between 3000-7000 MtCO2 in addition to storing potentially 1000 to 5000 MtCO2 in regional deep geologic formations in the period up to 2050. A similarly sized domestic CTL industry could result in 4000 to 5000 MtCO2 emitted to the atmosphere in addition to potentially 21,000 to 22,000 MtCO2 stored in regional deep geologic formations over the same period up to 2050. Preliminary analysis of regional CO2 storage capacity in locations where such facilities might be sited indicates that there appears to be sufficient storage capacity, primarily in deep saline formations, to accommodate the CO2 from these industries. However, additional analyses plus detailed regional and site characterization is needed, along with a closer examination of competing storage demands.

Dooley, James J.; Dahowski, Robert T.

2008-11-18

38

The future of forests and orangutans (Pongo abelii) in Sumatra: predicting impacts of oil palm plantations, road construction, and mechanisms for reducing carbon emissions from deforestation  

NASA Astrophysics Data System (ADS)

Payments for reduced carbon emissions from deforestation (RED) are now attracting attention as a way to halt tropical deforestation. Northern Sumatra comprises an area of 65 000 km2 that is both the site of Indonesia's first planned RED initiative, and the stronghold of 92% of remaining Sumatran orangutans. Under current plans, this RED initiative will be implemented in a defined geographic area, essentially a newly established, 7500 km2 protected area (PA) comprising mostly upland forest, where guards will be recruited to enforce forest protection. Meanwhile, new roads are currently under construction, while companies are converting lowland forests into oil palm plantations. This case study predicts the effectiveness of RED in reducing deforestation and conserving orangutans for two distinct scenarios: the current plan of implementing RED within the specific boundary of a new upland PA, and an alternative scenario of implementing RED across landscapes outside PAs. Our satellite-based spatially explicit deforestation model predicts that 1313 km2 of forest would be saved from deforestation by 2030, while forest cover present in 2006 would shrink by 22% (7913 km2) across landscapes outside PAs if RED were only to be implemented in the upland PA. Meanwhile, orangutan habitat would reduce by 16% (1137 km2), resulting in the conservative loss of 1384 orangutans, or 25% of the current total population with or without RED intervention. By contrast, an estimated 7824 km2 of forest could be saved from deforestation, with maximum benefit for orangutan conservation, if RED were to be implemented across all remaining forest landscapes outside PAs. Here, RED payments would compensate land users for their opportunity costs in not converting unprotected forests into oil palm, while the construction of new roads to service the marketing of oil palm would be halted. Our predictions suggest that Indonesia's first RED initiative in an upland PA may not significantly reduce deforestation in northern Sumatra and would have little impact on orangutan conservation because a large amount of forest inside the project area is protected de facto by being inaccessible, while lowland forests will remain exposed to the combined expansion of high-revenue plantations and road networks. In contrast, RED would be more effective in terms of its conservation impact if payments were extended to all remaining carbon-rich tropical forests, including lowland peat swamp forests, the preferred habitat for dense populations of orangutans, and if the construction of new roads was halted.

Gaveau, David L. A.; Wich, Serge; Epting, Justin; Juhn, Daniel; Kanninen, Markku; Leader-Williams, Nigel

2009-09-01

39

Black carbon emissions in China  

Microsoft Academic Search

Black carbon (BC) is an important aerosol species because of its global and regional influence on radiative forcing and its local effects on the environment and human health. We have estimated the emissions of BC in China, where roughly one-fourth of global anthropogenic emissions is believed to originate. China's high rates of usage of coal and biofuels are primarily responsible

David G. Streets; Shalini Gupta; Stephanie T. Waldhoff; Michael Q. Wang; Tami C. Bond; Bo Yiyun

2001-01-01

40

Trading permanent and temporary carbon emissions credits  

SciTech Connect

In this issue of Climatic Change, Van Kooten (2009) addresses an issue that has bedeviled negotiators since the drafting stage of the Kyoto Protocol. If we accept that increasing withdrawals of carbon dioxide from the atmpshere has the same net impact on the climate system as reducing emissions of carbon dioxide to the atmosphere, how do we design a system that allows trading of one for the other? As van Kooten expresses the challenge: 'The problem is that emissions reduction and carbon sequestration, while opposite sides of the same coin in some sense, are not directly comparable, thereby inhibiting their trade in carbon markets.' He explains: 'The difficulty centers on the length of time that mitigation strategies without CO{sub 2} from entering the atmosphere - the duration problem.' While reducing emissions of CO{sub 2} represents an essentially permanent benefit for the atmosphere, capturing CO{sub 2} that has been produced (whether capture is from the atmosphere or directly from, for example, the exhaust from power plants) there is the challenge of storing the carbon adn the risk that it will yet escape to the atmosphere. Permanent benefit to the atmosphere is often not assured for carbon sequestration activities. This is especially true if the carbon is taken up and stored in the biosphere - e.g. in forest trees or agricultural soils.

Marland, Gregg [ORNL; Marland, Eric [Appalachian State University

2009-08-01

41

Improving material management to reduce greenhouse gas emissions  

Microsoft Academic Search

Climate change due to greenhouse gas emissions caused by human actions is probably one of the major global environmental problems that we face today.\\u000aIn order to reduce the risk of climate change and the potential effects thereof,\\u000athe emission of greenhouse gases like carbon dioxide (CO2) and methane\\u000a(CH4 ) should be reduced.\\u000aMuch greenhouse gases are emitted due

Marko Peter Hekkert

2000-01-01

42

Carbon emission from global hydroelectric reservoirs revisited.  

PubMed

Substantial greenhouse gas (GHG) emissions from hydropower reservoirs have been of great concerns recently, yet the significant carbon emitters of drawdown area and reservoir downstream (including spillways and turbines as well as river reaches below dams) have not been included in global carbon budget. Here, we revisit GHG emission from hydropower reservoirs by considering reservoir surface area, drawdown zone and reservoir downstream. Our estimates demonstrate around 301.3 Tg carbon dioxide (CO2)/year and 18.7 Tg methane (CH4)/year from global hydroelectric reservoirs, which are much higher than recent observations. The sum of drawdown and downstream emission, which is generally overlooked, represents 42% CO2 and 67% CH4 of the total emissions from hydropower reservoirs. Accordingly, the global average emissions from hydropower are estimated to be 92g CO2/kWh and 5.7g CH4/kWh. Nonetheless, global hydroelectricity could currently reduce approximate 2,351 Tg CO2eq/year with respect to fuel fossil plant alternative. The new findings show a substantial revision of carbon emission from the global hydropower reservoirs. PMID:24943886

Li, Siyue; Zhang, Quanfa

2014-12-01

43

Baseline map of carbon emissions from deforestation in tropical regions.  

PubMed

Policies to reduce emissions from deforestation would benefit from clearly derived, spatially explicit, statistically bounded estimates of carbon emissions. Existing efforts derive carbon impacts of land-use change using broad assumptions, unreliable data, or both. We improve on this approach using satellite observations of gross forest cover loss and a map of forest carbon stocks to estimate gross carbon emissions across tropical regions between 2000 and 2005 as 0.81 petagram of carbon per year, with a 90% prediction interval of 0.57 to 1.22 petagrams of carbon per year. This estimate is 25 to 50% of recently published estimates. By systematically matching areas of forest loss with their carbon stocks before clearing, these results serve as a more accurate benchmark for monitoring global progress on reducing emissions from deforestation. PMID:22723420

Harris, Nancy L; Brown, Sandra; Hagen, Stephen C; Saatchi, Sassan S; Petrova, Silvia; Salas, William; Hansen, Matthew C; Potapov, Peter V; Lotsch, Alexander

2012-06-22

44

An Analysis of Fuel Demand and Carbon Emissions in China  

Microsoft Academic Search

Under the Kyoto Protocol to the United Nations Fr amework Convention on Climate Change, targets have been set for various developed countri es to reduce their carbon emissions. China's share of carbon emissions ranked the second highest in the w orld in 1996, only after the United States. Althou gh China was not formally required to achieve a reduct ion

Baiding Hu

45

Tracing Fuel Component Carbon in the Emissions from Diesel Engines  

Microsoft Academic Search

The addition of oxygenates to diesel fuel can reduce particulate emissions, but the underlying chemical pathways for the reductions are not well understood. While measurements of particulate matter (PM), unburned hydrocarbons (HC), and carbon monoxide (CO) are routine, determining the contribution of carbon atoms in the original fuel molecules to the formation of these undesired exhaust emissions has proven difficult.

B A Buchholz; C J Mueller; G C Martin; A S E Cheng; R W Dibble; B R Frantz

2002-01-01

46

Tracing fuel component carbon in the emissions from diesel engines  

Microsoft Academic Search

The addition of oxygenates to diesel fuel can reduce particulate emissions, but the underlying chemical pathways for the reductions are not well understood. While measurements of particulate matter (PM), unburned hydrocarbons (HC), and carbon monoxide (CO) are routine, determining the contribution of carbon atoms in the original fuel molecules to the formation of these undesired exhaust emissions has proven difficult.

Bruce A Buchholz; Charles J Mueller; Glen C Martin; A. S Cheng; Robert W Dibble; Brian R Frantz

2004-01-01

47

Technology Opportunities to Reduce U.S. Greenhouse Gas Emissions  

SciTech Connect

The rise in greenhouse gas emissions from fossil fuel combustion and industrial and agricultural activities has aroused international concern about the possible impacts of these emissions on climate. Greenhouse gases--mostly carbon dioxide, some methane, nitrous oxide and other trace gases--are emitted to the atmosphere, enhancing an effect in which heat reflected from the earth's surface is kept from escaping into space, as in a greenhouse. Thus, there is concern that the earth's surface temperature may rise enough to cause global climate change. Approximately 90% of U.S. greenhouse gas emissions from anthropogenic sources come from energy production and use, most of which are a byproduct of the combustion of fossil fuels. On a per capita basis, the United States is one of the world's largest sources of greenhouse gas emissions, comprising 4% of the world's population, yet emitting 23% of the world's greenhouse gases. Emissions in the United States are increasing at around 1.2% annually, and the Energy Information Administration forecasts that emissions levels will continue to increase at this rate in the years ahead if we proceed down the business-as-usual path. President Clinton has presented a two-part challenge for the United States: reduce greenhouse gas emissions and grow the economy. Meeting the challenge will mean that in doing tomorrow's work, we must use energy more efficiently and emit less carbon for the energy expended than we do today. To accomplish these goals, President Clinton proposed on June 26, 1997, that the United States ''invest more in the technologies of the future''. In this report to Secretary of Energy Pena, 47 technology pathways are described that have significant potential to reduce carbon dioxide emissions. The present study was completed before the December 1997 United Nations Framework Convention on Climate Change and is intended to provide a basis to evaluate technology feasibility and options to reduce greenhouse gas emissions. These technology pathways (which are described in greater detail in Appendix B, Technology Pathways) address three areas: energy efficiency, clean energy, and carbon sequestration (removing carbon from emissions and enhancing carbon storage). Based on an assessment of each of these technology pathways over a 30-year planning horizon, the directors of the Department of Energy's (DOE's) national laboratories conclude that success will require pursuit of multiple technology pathways to provide choices and flexibility for reducing greenhouse gas emissions. Advances in science and technology are necessary to reduce greenhouse gas emissions from the United States while sustaining economic growth and providing collateral benefits to the nation.

National Lab Directors, . .

2001-04-05

48

Black carbon emissions in China  

NASA Astrophysics Data System (ADS)

Black carbon (BC) is an important aerosol species because of its global and regional influence on radiative forcing and its local effects on the environment and human health. We have estimated the emissions of BC in China, where roughly one-fourth of global anthropogenic emissions is believed to originate. China's high rates of usage of coal and biofuels are primarily responsible for high BC emissions. This paper pays particular attention to the application of appropriate emission factors for China and the attenuation of these emissions where control devices are used. Nevertheless, because of the high degree of uncertainty associated with BC emission factors, we provide ranges of uncertainty for our emission estimates, which are approximately a factor of eight. In our central case, we calculate that BC emissions in China in 1995 were 1342 Gg, about 83% being generated by the residential combustion of coal and biofuels. We estimate that BC emissions could fall to 1224 Gg by 2020. This 9% decrease in BC emissions can be contrasted with the expected increase of 50% in energy use; the reduction will be obtained because of a transition to more advanced technology, including greater use of coal briquettes in place of raw coal in cities and towns. The increased use of diesel vehicles in the future will result in a greater share of the transport sector in total BC emissions. Spatially, BC emissions are predominantly distributed in an east-west swath across China's heartland, where the rural use of coal and biofuels for cooking and heating is widespread. This is in contrast to the emissions of most other anthropogenically derived air pollutants, which are closely tied to population and industrial centers.

Streets, David G.; Gupta, Shalini; Waldhoff, Stephanie T.; Wang, Michael Q.; Bond, Tami C.; Yiyun, Bo

49

Method of reducing NOx emissions in gasoline vehicles  

SciTech Connect

An unleaded fuel composition is described comprising a major amount of a hydrocarbon base fuel of the gasoline boiling range containing an amount effective to reduce NO[sub x] emissions from electronic port fuel injected engines of an ammonium compound selected from the group consisting of ammonium formate, ammonium propionate, ammonium dicitrate, ammonium carbamate, ammonium carbonate, ammonium acetate, and admixtures thereof.

Gwyn, J.E.

1993-08-10

50

Reducing emissions from uranium dissolving  

SciTech Connect

This study was designed to assess the feasibility of decreasing NO{sub x} emissions from the current uranium alloy scrap tray dissolving facility. In the current process, uranium scrap is dissolved in boiling nitric acid in shallow stainless-steel trays. As scrap dissolves, more metal and more nitric acid are added to the tray by operating personnel. Safe geometry is assured by keeping liquid level at or below 5 cm, the depth of a safe infinite slab. The accountability batch control system provides additional protection against criticality. Both uranium and uranium alloys are dissolved. Nitric acid is recovered from the vapors for reuse. Metal nitrates are sent to uranium recovery. Brown NO{sub x} fumes evolved during dissolving have occasionally resulted in a visible plume from the trays. The fuming is most noticeable during startup and after addition of fresh acid to a tray. Present environmental regulations are expected to require control of brown NO{sub x} emissions. A detailed review of the literature, indicated the feasibility of slightly altering process chemistry to favor the production of NO{sub 2} which can be scrubbed and recycled as nitric acid. Methods for controlling the process to manage offgas product distribution and to minimize chemical reaction hazards were also considered.

Griffith, W.L.; Compere, A.L.; Huxtable, W.P.; Googin, J.M.

1992-10-01

51

Reducing emissions from uranium dissolving  

SciTech Connect

This study was designed to assess the feasibility of decreasing NO[sub x] emissions from the current uranium alloy scrap tray dissolving facility. In the current process, uranium scrap is dissolved in boiling nitric acid in shallow stainless-steel trays. As scrap dissolves, more metal and more nitric acid are added to the tray by operating personnel. Safe geometry is assured by keeping liquid level at or below 5 cm, the depth of a safe infinite slab. The accountability batch control system provides additional protection against criticality. Both uranium and uranium alloys are dissolved. Nitric acid is recovered from the vapors for reuse. Metal nitrates are sent to uranium recovery. Brown NO[sub x] fumes evolved during dissolving have occasionally resulted in a visible plume from the trays. The fuming is most noticeable during startup and after addition of fresh acid to a tray. Present environmental regulations are expected to require control of brown NO[sub x] emissions. A detailed review of the literature, indicated the feasibility of slightly altering process chemistry to favor the production of NO[sub 2] which can be scrubbed and recycled as nitric acid. Methods for controlling the process to manage offgas product distribution and to minimize chemical reaction hazards were also considered.

Griffith, W.L.; Compere, A.L.; Huxtable, W.P.; Googin, J.M.

1992-10-01

52

World energy consumption and carbon dioxide emissions : 1950-2050  

E-print Network

Emissions of carbon dioxide form combustion of fossil fuels, which may contribute to long-term climate change, are projected through 2050 using reduced form models estimated with national-level panel data for the period ...

Schmalensee, Richard

1995-01-01

53

Economic growth and carbon emission control  

NASA Astrophysics Data System (ADS)

The question about whether environmental improvement is compatible with continued economic growth remains unclear and requires further study in a specific context. This study intends to provide insight on the potential for carbon emissions control in the absence of international agreement, and connect the empirical analysis with theoretical framework. The Chinese electricity generation sector is used as a case study to demonstrate the problem. Both social planner and private problems are examined to derive the conditions that define the optimal level of production and pollution. The private problem will be demonstrated under the emission regulation using an emission tax, an input tax and an abatement subsidy respectively. The social optimal emission flow is imposed into the private problem. To provide tractable analytical results, a Cobb-Douglas type production function is used to describe the joint production process of the desired output and undesired output (i.e., electricity and emissions). A modified Hamiltonian approach is employed to solve the system and the steady state solutions are examined for policy implications. The theoretical analysis suggests that the ratio of emissions to desired output (refer to 'emission factor'), is a function of productive capital and other parameters. The finding of non-constant emission factor shows that reducing emissions without further cutting back the production of desired outputs is feasible under some circumstances. Rather than an ad hoc specification, the optimal conditions derived from our theoretical framework are used to examine the relationship between desired output and emission level. Data comes from the China Statistical Yearbook and China Electric Power Yearbook and provincial information of electricity generation for the year of 1993-2003 are used to estimate the Cobb-Douglas type joint production by the full information maximum likelihood (FIML) method. The empirical analysis shed light on the optimal policies of emissions control required for achieving the social goal in a private context. The results suggest that the efficiency of abatement technology is crucial for the timing of executing the emission tax. And emission tax is preferred to an input tax, as long as the detection of emissions is not costly and abatement technology is efficient. Keywords: Economic growth, Carbon emission, Power generation, Joint production, China

Zhang, Zhenyu

54

REVIEW PAPER Strategies for reducing the carbon footprint of field crops  

E-print Network

REVIEW PAPER Strategies for reducing the carbon footprint of field crops for semiarid areas emission. To provide the potential solution, we estimated the carbon footprint [i.e., the total amount the effect of crop sequences on the carbon footprint of durum wheat. Key strategies for reducing the carbon

Paris-Sud XI, Université de

55

Carbon Emission Capstone (title provided or enhanced by cataloger)  

NSDL National Science Digital Library

There are two ways to reduce net emissions of carbon dioxide: limit how much carbon dioxide is emitted into the atmosphere as we burn fossil fuels, or increase the rate at which it is absorbed. In this lesson, discussion topics include the Kyoto Protocol and the use of carbon credits to reduce emissions of carbon dioxide into the atmosphere. Students can listen to a National Public Radio show that reports on new research that both illuminates and further complicates the picture of how the Earth is warming. The lesson includes an activity in which students examine their personal annual carbon emissions (calculated in the previous exercise) and determine how many trees it would take to sequester these emissions. They will then extrapolate this number to the populations of their school campus and their county.

Pratte, John

56

Carbon emission from farm operations.  

PubMed

This manuscript is a synthesis of the available information on energy use in farm operations, and its conversion into carbon equivalent (CE). A principal advantage of expressing energy use in terms of carbon (C) emission as kg CE lies in its direct relation to the rate of enrichment of atmospheric concentration of CO2. Synthesis of the data shows that estimates of emissions in kg CE/ha are 2-20 for different tillage operations, 1-1.4 for spraying chemicals, 2-4 for drilling or seeding and 6-12 for combine harvesting. Similarly, estimates of C emissions in kg CE/kg for different fertilizer nutrients are 0.9-1.8 for N, 0.1-0.3 for P2O5, 0.1-0.2 for K20 and 0.03-0.23 for lime. Estimates of C emission in kg CE/kg of active ingredient (a.i.) of different pesticides are 6.3 for herbicides, 5.1 for insecticides and 3.9 for fungicides. Irrigation, lifting water from deep wells and using sprinkling systems, emits 129+/-98 kg CE for applying 25 cm of water and 258+/-195 for 50 cm of water. Emission for different tillage methods are 35.3 kg CE/ha for conventional till, 7.9 kg CE/ha for chisel till or minimum till, and 5.8 kg CE/ha for no-till method of seedbed preparation. In view of the high C costs of major inputs, sustainable management of agricultural ecosystems implies that an output/input ratio, expressed either as gross or net output of C, must be >1 and has an increasing trend over time. PMID:15196846

Lal, R

2004-09-01

57

Method for reducing CO2, CO, NOX, and SOx emissions  

DOEpatents

Industrial combustion facilities are integrated with greenhouse gas-solidifying fertilizer production reactions so that CO.sub.2, CO, NO.sub.x, and SO.sub.x emissions can be converted prior to emission into carbonate-containing fertilizers, mainly NH.sub.4 HCO.sub.3 and/or (NH.sub.2).sub.2 CO, plus a small fraction of NH.sub.4 NO.sub.3 and (NH.sub.4).sub.2 SO.sub.4. The invention enhances sequestration of CO.sub.2 into soil and the earth subsurface, reduces N0.sub.3.sup.- contamination of surface and groundwater, and stimulates photosynthetic fixation of CO.sub.2 from the atmosphere. The method for converting CO.sub.2, CO, NO.sub.x, and SO.sub.x emissions into fertilizers includes the step of collecting these materials from the emissions of industrial combustion facilities such as fossil fuel-powered energy sources and transporting the emissions to a reactor. In the reactor, the CO.sub.2, CO, N.sub.2, SO.sub.x, and/or NO.sub.x are converted into carbonate-containing fertilizers using H.sub.2, CH.sub.4, or NH.sub.3. The carbonate-containing fertilizers are then applied to soil and green plants to (1) sequester inorganic carbon into soil and subsoil earth layers by enhanced carbonation of groundwater and the earth minerals, (2) reduce the environmental problem of NO.sub.3.sup.- runoff by substituting for ammonium nitrate fertilizer, and (3) stimulate photosynthetic fixation of CO.sub.2 from the atmosphere by the fertilization effect of the carbonate-containing fertilizers.

Lee, James Weifu (Oak Ridge, TN); Li, Rongfu (Zhejiang, CH)

2002-01-01

58

CARBON EMISSIONS ECONOMIC INTENSITY INDEX (CEEII)  

EPA Science Inventory

The core concept of the CEEII is to understand, at the state level, the carbon emissions from energy consumption in relation to the value of the activity that generates the emissions. The CEEII treats carbon emissions as an input to producing the activity?s value and assesses th...

59

Energy efficiency procedures for agricultural machinery used in onion cultivation (Allium fistulosum) as an alternative to reduce carbon emissions under the clean development mechanism at Aquitania (Colombia)  

NASA Astrophysics Data System (ADS)

Climate change has both causes and consequences over agriculture. This paper focuses on the first element and presents scenarios for ASOLAGO -an onion cropper's association in Colombia with 250 members- to reduce their carbon footprint. It evaluates a case study at "La Primavera" farm using a methodology approved by the United Nations Framework Convention on Climate Change. Land preparation and crop irrigation were analyzed as stages in order to propose energy efficiency alternatives for both the farm and the association. They include field efficiency, fuel economy and energy efficiency from biofuels for the first stage as well as solar and wind energy supply for the second. A cost-benefit analysis to generate additional income selling additional power produced by the system to the National Grid was done.

Ochoa, K.; Carrillo, S.; Gutierrez, L.

2014-06-01

60

Carbon emissions from tropical forest degradation caused by logging  

NASA Astrophysics Data System (ADS)

The focus of land-use related efforts in developing countries to reduce carbon emissions has been on slowing deforestation, yet international agreements are to reduce emissions from both deforestation and forest degradation (REDD). The second D is poorly understood and accounted for a number of technical and policy reasons. Here we introduce a complete accounting method for estimating emission factors from selective timber harvesting, a substantial form of forest degradation in many tropical developing countries. The method accounts separately for emissions from the extracted log, from incidental damage to the surrounding forest, and from logging infrastructure, and emissions are expressed as units of carbon per cubic meter of timber extracted to allow for simple application to timber harvesting statistics. We applied the method in six tropical countries (Belize, Bolivia, Brazil, Guyana, Indonesia, and Republic of Congo), resulting in total emission factors of 0.99-2.33 Mg C m-3. In all cases, emissions were dominated by damage to surrounding vegetation and the infrastructure rather than the logs themselves, and total emissions represented about 3-15% of the biomass carbon stocks of the associated unlogged forests. We then combined the emission factors with country level logging statistics for nine key timber producing countries represented by our study areas to gain an understanding of the order of magnitude of emissions from degradation compared to those recently reported for deforestation in the same countries. For the nine countries included, emissions from logging were on average equivalent to about 12% of those from deforestation. For those nine countries with relatively low emissions from deforestation, emissions from logging were equivalent to half or more of those from deforestation, whereas for those countries with the highest emissions from deforestation, emissions from logging were equivalent to <10% of those from deforestation. Understanding how to account emissions and the magnitude of each emissions source resulting from tropical timber harvesting practices helps identify where there are opportunities to reduce emissions from the second D in REDD.

Pearson, Timothy R. H.; Brown, Sandra; Casarim, Felipe M.

2014-03-01

61

REDUCING GREENHOUSE GAS EMISSIONS FROM DEFORESTATION IN DEVELOPING  

E-print Network

REDUCING GREENHOUSE GAS EMISSIONS FROM DEFORESTATION IN DEVELOPING COUNTRIES: REVISITING Change Research Working Paper 115 #12;REDUCING GREENHOUSE GAS EMISSIONS FROM DEFORESTATION IN DEVELOPING on Reducing Emissions from Deforestation and Degradation (REDD) under the United Nations Framework Convention

Watson, Andrew

62

Hydrocarbon and carbon monoxide emissions from biomass burning in Brazil  

Microsoft Academic Search

Field measurements of hydrocarbon emissions from biomass burning in the cerrado (grasslands) and selva (tropical forest) regions of Brazil in 1979 and 1980 are characterized and quantified here. Regional consequences of burning activities include increased background mixing ratios of carbon monoxide and ozone, as well as reduced visibility, over extensive areas. Global extrapolation of the emission rate of hydrocarbons from

J. P. Greenberg; P. R. Zimmerman; L. Heidt; W. Pollock

1984-01-01

63

Wildlife conservation and reduced emissions from deforestation in a case study of Nantu National Park,  

E-print Network

Wildlife conservation and reduced emissions from deforestation in a case study of Nantu National Measures of success a b s t r a c t Discussions on how to reduce carbon emissions from deforestation of the role of protected area (PA) status in reducing tropical deforestation. This study employs a range

Malhi, Yadvinder

64

Reducing GHG emissions in the United States' transportation sector  

SciTech Connect

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 in 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.

Das, Sujit [ORNL; Andress, David A [ORNL; Nguyen, Tien [U.S. DOE

2011-01-01

65

Reduced Martian Carbon: Evidence from Martian Meteorites  

NASA Technical Reports Server (NTRS)

Identification of indigenous reduced carbon species on Mars has been a challenge since the first hypotheses about life on Mars were proposed. Ranging from the early astronomical measurements to analyses of samples from the Martian surface in the form of Martian meteorites. The first direct attempt to analyze the carbon species on the surface was in 1976 with the Viking GC-MS in-situ experiment which gave inconclusive results at two sites on Mars [1]. With the recognition in 1983 that samples of the Martian surface were already present on Earth in the form of Martian meteorites by Bogard and Johnson [2] new opportunities became available for direct study of Mars's samples in te rlraesbtrioalratories. Carbon isotopic compositional information suggested a reduced carbon component was present in the Martian meteorites [3-5]. Polycyclic aromatic hydrocarbons associated with carbonate globules in ALH84001 were later identified [6,7]. Jull et al [8] noted that an insoluble component was present within Nakhla and more than 75% of its C lacked any 14C, which is modern-day carbon contaminant. This carbon fraction was believed to be either indigenous (i..e. Martian) or ancient meteoritic carbon phase. Within the fractures of Nakhla and ALH84001, Fisk et al [9,10] identified reduced carbon-enriched areas. Gibson et al. [11] using a combination of NanoSIMS, Focused Electron microscopy, Laser Raman Spectroscopy and Stepped-Combustion Static Mass Spectrometry analyses the presence of possible indigenous reduced carbon components within the 1.3 Ga old Nakhla.

Gibson, Everett K.; McKay, David S.; Thomas-Keprta, Kathie L.; Clemett, SImon J.; Pillinger, COlin T.; Wright, Ian P.; Verchovsky, A. P.

2010-01-01

66

Structuring economic incentives to reduce emissions from deforestation within Indonesia  

PubMed Central

We estimate and map the impacts that alternative national and subnational economic incentive structures for reducing emissions from deforestation (REDD+) in Indonesia would have had on greenhouse gas emissions and national and local revenue if they had been in place from 2000 to 2005. The impact of carbon payments on deforestation is calibrated econometrically from the pattern of observed deforestation and spatial variation in the benefits and costs of converting land to agriculture over that time period. We estimate that at an international carbon price of $10/tCO2e, a mandatory incentive structure, such as a cap-and-trade or symmetric tax-and-subsidy program, would have reduced emissions by 163247 MtCO2e/y (2031% below the without-REDD+ reference scenario), while generating a programmatic budget surplus. In contrast, a basic voluntary incentive structure modeled after a standard payment-for-environmental-services program would have reduced emissions nationally by only 4576 MtCO2e/y (69%), while generating a programmatic budget shortfall. By making four policy improvementspaying for net emission reductions at the scale of an entire district rather than site-by-site; paying for reductions relative to reference levels that match business-as-usual levels; sharing a portion of district-level revenues with the national government; and sharing a portion of the national government's responsibility for costs with districtsan improved voluntary incentive structure would have been nearly as effective as a mandatory incentive structure, reducing emissions by 136207 MtCO2e/y (1726%) and generating a programmatic budget surplus. PMID:22232665

Busch, Jonah; Lubowski, Ruben N.; Godoy, Fabiano; Steininger, Marc; Yusuf, Arief A.; Austin, Kemen; Hewson, Jenny; Juhn, Daniel; Farid, Muhammad; Boltz, Frederick

2012-01-01

67

Structuring economic incentives to reduce emissions from deforestation within Indonesia.  

PubMed

We estimate and map the impacts that alternative national and subnational economic incentive structures for reducing emissions from deforestation (REDD+) in Indonesia would have had on greenhouse gas emissions and national and local revenue if they had been in place from 2000 to 2005. The impact of carbon payments on deforestation is calibrated econometrically from the pattern of observed deforestation and spatial variation in the benefits and costs of converting land to agriculture over that time period. We estimate that at an international carbon price of $10/tCO(2)e, a "mandatory incentive structure," such as a cap-and-trade or symmetric tax-and-subsidy program, would have reduced emissions by 163-247 MtCO(2)e/y (20-31% below the without-REDD+ reference scenario), while generating a programmatic budget surplus. In contrast, a "basic voluntary incentive structure" modeled after a standard payment-for-environmental-services program would have reduced emissions nationally by only 45-76 MtCO(2)e/y (6-9%), while generating a programmatic budget shortfall. By making four policy improvements--paying for net emission reductions at the scale of an entire district rather than site-by-site; paying for reductions relative to reference levels that match business-as-usual levels; sharing a portion of district-level revenues with the national government; and sharing a portion of the national government's responsibility for costs with districts--an "improved voluntary incentive structure" would have been nearly as effective as a mandatory incentive structure, reducing emissions by 136-207 MtCO(2)e/y (17-26%) and generating a programmatic budget surplus. PMID:22232665

Busch, Jonah; Lubowski, Ruben N; Godoy, Fabiano; Steininger, Marc; Yusuf, Arief A; Austin, Kemen; Hewson, Jenny; Juhn, Daniel; Farid, Muhammad; Boltz, Frederick

2012-01-24

68

Degassing of reduced carbon from planetary basalts.  

PubMed

Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO2)] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO2 higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO2, we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO2 less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO2 controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential. PMID:23569260

Wetzel, Diane T; Rutherford, Malcolm J; Jacobsen, Steven D; Hauri, Erik H; Saal, Alberto E

2013-05-14

69

Degassing of reduced carbon from planetary basalts  

PubMed Central

Degassing of planetary interiors through surface volcanism plays an important role in the evolution of planetary bodies and atmospheres. On Earth, carbon dioxide and water are the primary volatile species in magmas. However, little is known about the speciation and degassing of carbon in magmas formed on other planets (i.e., Moon, Mars, Mercury), where the mantle oxidation state [oxygen fugacity (fO2)] is different from that of the Earth. Using experiments on a lunar basalt composition, we confirm that carbon dissolves as carbonate at an fO2 higher than -0.55 relative to the iron wustite oxygen buffer (IW-0.55), whereas at a lower fO2, we discover that carbon is present mainly as iron pentacarbonyl and in smaller amounts as methane in the melt. The transition of carbon speciation in mantle-derived melts at fO2 less than IW-0.55 is associated with a decrease in carbon solubility by a factor of 2. Thus, the fO2 controls carbon speciation and solubility in mantle-derived melts even more than previous data indicate, and the degassing of reduced carbon from Fe-rich basalts on planetary bodies would produce methane-bearing, CO-rich early atmospheres with a strong greenhouse potential. PMID:23569260

Wetzel, Diane T.; Rutherford, Malcolm J.; Jacobsen, Steven D.; Hauri, Erik H.; Saal, Alberto E.

2013-01-01

70

Sensitivity of climate to cumulative carbon emissions due to compensation of ocean heat and carbon uptake  

NASA Astrophysics Data System (ADS)

Climate model experiments reveal that transient global warming is nearly proportional to cumulative carbon emissions on multi-decadal to centennial timescales. However, it is not quantitatively understood how this near-linear dependence between warming and cumulative carbon emissions arises in transient climate simulations. Here, we present a theoretically derived equation of the dependence of global warming on cumulative carbon emissions over time. For an atmosphere-ocean system, our analysis identifies a surface warming response to cumulative carbon emissions of 1.5 +/- 0.7 K for every 1,000 Pg of carbon emitted. This surface warming response is reduced by typically 10-20% by the end of the century and beyond. The climate response remains nearly constant on multi-decadal to centennial timescales as a result of partially opposing effects of oceanic uptake of heat and carbon. The resulting warming then becomes proportional to cumulative carbon emissions after many centuries, as noted earlier. When we incorporate estimates of terrestrial carbon uptake, the surface warming response is reduced to 1.1 +/- 0.5 K for every 1,000 Pg of carbon emitted, but this modification is unlikely to significantly affect how the climate response changes over time. We suggest that our theoretical framework may be used to diagnose the global warming response in climate models and mechanistically understand the differences between their projections.

Goodwin, Philip; Williams, Richard G.; Ridgwell, Andy

2015-01-01

71

Estakhri and Saylak 1 Potential for Reduced Greenhouse Gas Emissions in Texas Through the Use of  

E-print Network

Estakhri and Saylak 1 Potential for Reduced Greenhouse Gas Emissions in Texas Through the Use with the challenge to reduce greenhouse gas emissions, policy makers have traditionally targeted the transportation of the greenhouse gas carbon dioxide (CO2). Besides other raw materials, each ton of portland cement requires

72

The Uncertain Carbon Emissions in China (Invited)  

NASA Astrophysics Data System (ADS)

Anthropogenic fossil fuel emissions are considered as being well understood with a low uncertainty (9.1 0.5Gt C yr-1). By using full transparency emission inventory which the energy consumption, fuel heating values, carbon content and oxidation rate reported separately in sectoal level, here we found new 2.1 Gt C yr-1 (23% of global total) uncertainties of carbon emission inventory, which mainly contributed by the mass energy use and consumption coal quality in China and by misunderstanding of fuel quality in international fossil fuel trade. Increment of coal's carbon emission in China and India are equivalent to 130 % of global total coal's emission growth during 2008-2010, by using macro energy statistics and bottom up coal mine datasets, the difference carbon emission estimates from China and India can up to 1.32 C yr-1. Emissions from international trade of coal could produce another 0.08 Gt C yr-1 uncertainty. These new emerging 1.4 Gt C yr-1 uncertainties implies a significant mis-estimation of human induced carbon emissions and a new dominating factor in contributing the global carbon budget residual.

Liu, Z.; Guan, D.

2013-12-01

73

Nanofiber Based Carbon Capture Technology to Reduce the CO2 Emissions at GSU Campus PI: Mujibur Rahman Khan, Co-PI: Spencer Harp, Mechanical Engineering Department  

E-print Network

Canister placed after catalytic converter Motivation: This is a pilot project to explore the potential. · Installation and performance testing of filters at the CO2 emission sites (automobile catalytic converters

Hutcheon, James M.

74

Carbon Emissions Analysis of Rail Resurfacing Work: A Case Study, Practical Guideline, and Systems Thinking Approach  

E-print Network

Carbon pollution has become a sensitive topic across the globe in recent times. In Australia, incentive has been provided to industry in order to reduce carbon emissions in heavy polluting industries. The railway transportation ...

Krezo, S.

75

Reduced Coronal Emission Above Large Isolated Sunspots  

NASA Astrophysics Data System (ADS)

We analysed specific regions of reduced soft X-ray and microwave emission in five large isolated sunspots. The Nobeyama Radioheliograph 17 GHz observations reveal a local depression of microwave brightness in the peripheral area of the sunspots. The depression regions appear light (weak absorption) in the He 10830 line in areas with extended (open) field lines, as indicated by potential field source surface model (PFSS) extrapolations up to 1.5 R?. The observed depressions of 3 - 8 % in ordinary mode at 17 GHz are interpreted as resulting from free-free emission when the plasma density is lower by 5 - 10 %. Our model estimates show that the decrease in density in both the coronal and the lower layers above the depression region accounts for the depression. These depression regions lend themselves well to marking the location of outward plasma motions.

Ryabov, B. I.; Gary, D. E.; Peterova, N. G.; Shibasaki, K.; Topchilo, N. A.

2015-01-01

76

Direct carbon dioxide emissions from civil aircraft  

NASA Astrophysics Data System (ADS)

Global airlines consume over 5 million barrels of oil per day, and the resulting carbon dioxide (CO2) emitted by aircraft engines is of concern. This article provides a contemporary review of the literature associated with the measures available to the civil aviation industry for mitigating CO2 emissions from aircraft. The measures are addressed under two categories - policy and legal-related measures, and technological and operational measures. Results of the review are used to develop several insights into the challenges faced. The analysis shows that forecasts for strong growth in air-traffic will result in civil aviation becoming an increasingly significant contributor to anthropogenic CO2 emissions. Some mitigation-measures can be left to market-forces as the key-driver for implementation because they directly reduce airlines' fuel consumption, and their impact on reducing fuel-costs will be welcomed by the industry. Other mitigation-measures cannot be left to market-forces. Speed of implementation and stringency of these measures will not be satisfactorily resolved unattended, and the current global regulatory-framework does not provide the necessary strength of stewardship. A global regulator with teeth' needs to be established, but investing such a body with the appropriate level of authority requires securing an international agreement which history would suggest is going to be very difficult. If all mitigation-measures are successfully implemented, it is still likely that traffic growth-rates will continue to out-pace emissions reduction-rates. Therefore, to achieve an overall reduction in CO2 emissions, behaviour change will be necessary to reduce demand for air-travel. However, reducing demand will be strongly resisted by all stakeholders in the industry; and the ticket price-increases necessary to induce the required reduction in traffic growth-rates place a monetary-value on CO2 emissions of approximately 7-100 times greater than other common valuations. It is clear that, whilst aviation must remain one piece of the transport-jigsaw, environmentally a global regulator with teeth' is urgently required.

Grote, Matt; Williams, Ian; Preston, John

2014-10-01

77

Reducing greenhouse gas emissions in Czechoslovakia  

SciTech Connect

In this paper are presented important findings on the potential for energy conservation and carbon emissions reduction over the coming decades in Czechoslovakia. The authors describe the state of the energy use in Czechoslovakia today and the measures required to transform its energy system to a market-based economy oriented towards the environmental goal of decreased energy intensity. This work furthers our understanding of the need for energy efficiency in the newly forming market economies of East and Central Europe. This paper is part of a series of country studies sponsored by the Global Climate Division of the Office of Policy, Planning, and Evaluation, United States Environmental Protection Agency (EPA). We have completed similar studies in Canada, the former Soviet Union, France, Hungary, Italy, Japan, Poland the United Kingdom, and the United States. Research is currently underway or planned in Bulgaria, Romania, and Ukraine.

Kostalova, M. (Office of International Economic Corp., Ministry of Foreign Affairs, Prague (Czechoslovakia)); Suk, J. (Inst. for Forecasting, Czechoslovak Academy of Sciences, Prague (Czechoslovakia)); Kolar, S. (Pacific Northwest Lab., Richland, WA (United States))

1991-12-01

78

Field emission properties of the graphenated carbon nanotube electrode  

NASA Astrophysics Data System (ADS)

Reduced graphene oxide-coated carbon nanotubes (RGO-CNT) electrodes have been prepared by hot filament chemical vapour deposition system in one-step growth process. We studied RGO-CNT electrodes behaviour as cold cathode in field emission test. Our results show that RGO-CNT retain the low threshold voltage typical of CNTs, but with greatly improved emission current stability. The field emission enhancement value is significantly higher than that expected being caused by geometric effect (height divided by the radius of nanotube). This suggested that the field emission of this hybrid structure is not only from a single tip, but eventually it is from several tips with contribution of graphene nanosheets at CNT's walls. This phenomenon explains why the graphenated carbon nanotubes do not burn out as quickly as CNT does until emission ceases completely. These preliminaries results make nanocarbon materials good candidates for applications as electron sources for several devices.

Zanin, H.; Ceragioli, H. J.; Peterlevitz, A. C.; Baranauskas, Vitor; Marciano, F. R.; Lobo, A. O.

2015-01-01

79

Estimating carbon emissions from African wildfires  

Microsoft Academic Search

We developed a technique for studying seasonal and interannual variation in pyrogenic carbon emissions from Africa using a modelling approach that scales burned area estimates from L3JRC, a map recently generated from remote sensing of burn scars instead of active fires. Carbon fluxes were calculated by the novel fire model SPITFIRE embedded within the dynamic vegetation model framework LPJ-GUESS, using

V. Lehsten; K. Tansey; H. Balzter; K. Thonicke; A. Spessa; U. Weber; B. Smith; A. Arneth

2009-01-01

80

Carbon Emission Reduction using Pinch Analysis  

Microsoft Academic Search

Energy saving and emission reduction are the effective strategies to deal with the challenge of climate changes and energy problems. To support such strategies, target-oriented pinch analysis is a recommended method for identifying a systematic solution to energy planning and management problems. In this paper, regional carbon dioxide (CO2) emission pinch analysis (CEPA) is proposed to determine the target of

Xiao-ping Jia; Cai-Hong Liu; Yu Qian

2010-01-01

81

Reducing greenhouse gas emissions for climate stabilization: framing regional options  

SciTech Connect

The Intergovernmental Panel on Climate Change (IPCC) has stated that stabilizing atmospheric CO{sub 2} concentrations will require reduction of global greenhouse gas (GHG) emissions by as much as 80% by 2050. Subnational efforts to cut emissions will inform policy development nationally and globally. We projected GHG mitigation strategies for Minnesota, which has adopted a strategic goal of 80% emissions reduction by 2050. A portfolio of conservation strategies, including electricity conservation, increased vehicle fleet fuel efficiency, and reduced vehicle miles traveled, is likely the most cost-effective option for Minnesota and could reduce emissions by 18% below 2005 levels. An 80% GHG reduction would require complete decarbonization of the electricity and transportation sectors, combined with carbon capture and sequestration at power plants, or deep cuts in other relatively more intransigent GHG-emitting sectors. In order to achieve ambitious GHG reduction goals, policymakers should promote aggressive conservation efforts, which would probably have negative net costs, while phasing in alternative fuels to replace coal and motor gasoline over the long-term. 31 refs., 3 figs., 1 tab.

Laura Schmitt Olabisi; Peter B. Reich; Kris A. Johnson; Anne R. Kapuscinski; Sangwon Suh; Elizabeth J. Wilson [University of Minnesota, Saint Paul, MN (United States). Ecosystem Science and Sustainability Initiative

2009-03-15

82

Possibilities to reduce carbon emissions in Brazilian Amazon region with non timber biomass valorization: The case of biofuels produced by vegetable tropical oils  

SciTech Connect

Brazil`s annual rate of deforestation reached 2.1 million ha or about 13.6% of the total annual rate of deforestation for the whole tropical area in the world during 1981--1990. Today, the extent of gross deforestation is 10.9% of the tropical closed forest area. Relative to Brazilian participation in the greenhouse effect, the changes in forest area and associated biomass burning in Amazon region are responsible for about 25.5% of CO{sub 2} emissions in the tropics. Harvest of the non-timber biomass products may be important as a potentially sustainable use of forest in some areas. An excellent option to promote these biomass products is to provide energy and industrial goods for the Amazon communities and other external markets. In this work, the biofuels produced by vegetable tropical oils and their by-products are analyzed in relation to job creation, economics and environmental impacts, with special regards concerning the limitation of the atmospheric emissions of greenhouse gases.

Freitas, M.A.V. de; Rosa, L.P. [Universidade Federal, Rio de Janeiro (Brazil); Lascio, M.A. Di [UFRS, Santa Catarina (Brazil); [Ecole Polytechnique, Grenoble (France)

1996-12-31

83

Electron emission properties of carbon nanotubes  

NASA Astrophysics Data System (ADS)

We report on the field emission properties of carbon nanotubes, focusing on current density versus electric field ( J- F) characteristics and the spacing between the emitter and collector. We grew carbon nanotubes on SUS304, nickel, Inconel-600, and Invar-42 substrates using plasma-enhanced chemical vapor deposition, using methane gas as the carbon source and hydrogen gas as the catalyst and dilution gas. We found that nanotubes grew fastest on Invar-42. Nanotubes were distributed from 50 to 100 nm in diameter and from 1 to 30 ?m long. Onset field of the field emission was 0.7 V/?m and the current density was 1 mA/cm 2 at an electric field of 3.0 V/?m. A Fowler-Nordheim plot was made. Field enhancement factor ? and emission area ? were calculated and compared between substrates. Using nickel on quartz glass, carbon nanotubes were selectively fabricated on metal lines on quartz glass.

Hirakawa, Masaaki; Sonoda, Saki; Tanaka, Chiaki; Murakami, Hirohiko; Yamakawa, Hiroyuki

2001-01-01

84

Estimating carbon emissions from African wildfires  

NASA Astrophysics Data System (ADS)

Africa is a continent dominated by fire. Vegetation fires, occurring naturally or human-ignited as a land management practice, have a long history in the continent's savannah ecosystems. These fires contribute substantially to the total carbon emissions (e.g. as CO2, CO, CH4, Volatile Organic Compounds, Black Carbon) over large parts of the continent. Many recent attempts to assess the total area burnt and the amount of carbon emitted have been based on satellite remote sensing of active fires. To calculate emissions, the burned area estimates are typically multiplied with emission factors that are specific for each compound and land cover type, or used to distribute output from a biogeochemical model spatially. We developed a technique for estimating carbon emissions using a modelling approach to scale burned area estimates from L3JRC, a map recently generated from remote sensing of burn scars instead of active fires. Carbon fluxes were calculated by the novel fire model SPITFIRE embedded within the dynamic vegetation model framework LPJ-GUESS, using daily climate input. For the time period from 2001 to 2005 an average area of 195.524104 km2 was burned annually, releasing an average of 72370 Tg C to the atmosphere; these estimates for the biomass burned are within the range of previously published estimates. Despite the fact that the majority of wildfires are ignited by humans, strong relationships with climatic conditions have been identified in savannas worldwide, driving inter-annual variability. Our investigation of the relationships amongst carbon emissions and its potential drivers, available litter and precipitation showed that burned area as well as carbon emissions show a uni-modal response to precipitation with a maximum at ca. 1000 mm annual precipitation for burned area and emissions and a maximum of ca. 1200 mm annual precipitation for litter availability.

Lehsten, V.; Tansey, K. J.; Balzter, H.; Thonicke, K.; Spessa, A.; Weber, U.; Smith, B.; Arneth, A.

2008-08-01

85

Reducing VOC Press Emission from OSB Manufacturing  

SciTech Connect

Current regulations require industry to meet air emission standards with regard to particulates, volatile organic compounds (VOCs), hazardous air pollutants (HAPs) and other gases. One of many industries that will be affected by the new regulations is the wood composites industry. This industry generates VOCs, HAPs, and particulates mainly during the drying and pressing of wood. Current air treatment technologies for the industry are expensive to install and operate. As regulations become more stringent, treatment technologies will need to become more efficient and cost effective. The overall objective of this study is to evaluate the use of process conditions and chemical additives to reduce VOC/HAPs in air emitted from presses and dryers during the production of oriented strand board.

Dr. Gary D. McGinnis; Laura S. WIlliams; Amy E. Monte; Jagdish Rughani: Brett A. Niemi; Thomas M. Flicker

2001-12-31

86

Allowable carbon emissions lowered by multiple climate targets.  

PubMed

Climate targets are designed to inform policies that would limit the magnitude and impacts of climate change caused by anthropogenic emissions of greenhouse gases and other substances. The target that is currently recognized by most world governments places a limit of two degrees Celsius on the global mean warming since preindustrial times. This would require large sustained reductions in carbon dioxide emissions during the twenty-first century and beyond. Such a global temperature target, however, is not sufficient to control many other quantities, such as transient sea level rise, ocean acidification and net primary production on land. Here, using an Earth system model of intermediate complexity (EMIC) in an observation-informed Bayesian approach, we show that allowable carbon emissions are substantially reduced when multiple climate targets are set. We take into account uncertainties in physical and carbon cycle model parameters, radiative efficiencies, climate sensitivity and carbon cycle feedbacks along with a large set of observational constraints. Within this framework, we explore a broad range of economically feasible greenhouse gas scenarios from the integrated assessment community to determine the likelihood of meeting a combination of specific global and regional targets under various assumptions. For any given likelihood of meeting a set of such targets, the allowable cumulative emissions are greatly reduced from those inferred from the temperature target alone. Therefore, temperature targets alone are unable to comprehensively limit the risks from anthropogenic emissions. PMID:23823728

Steinacher, Marco; Joos, Fortunat; Stocker, Thomas F

2013-07-11

87

On-site denitrification beds could reduce indirect greenhouse gas emissions from agricultural drainage waters  

Technology Transfer Automated Retrieval System (TEKTRAN)

Nitrate (NO3-) laden agricultural drainage waters are non-point sources of indirect nitrous oxide (N2O) emissions, which represent a significant fraction of total N2O emissions in the USA. On-site denitrification beds filled with woodchips were used to reduce NO3- under carbon rich anaerobic conditi...

88

Cumulative carbon emissions, emissions floors and short-term rates of warming: implications for policy.  

PubMed

A number of recent studies have found a strong link between peak human-induced global warming and cumulative carbon emissions from the start of the industrial revolution, while the link to emissions over shorter periods or in the years 2020 or 2050 is generally weaker. However, cumulative targets appear to conflict with the concept of a 'floor' in emissions caused by sectors such as food production. Here, we show that the introduction of emissions floors does not reduce the importance of cumulative emissions, but may make some warming targets unachievable. For pathways that give a most likely warming up to about 4C, cumulative emissions from pre-industrial times to year 2200 correlate strongly with most likely resultant peak warming regardless of the shape of emissions floors used, providing a more natural long-term policy horizon than 2050 or 2100. The maximum rate of CO(2)-induced warming, which will affect the feasibility and cost of adapting to climate change, is not determined by cumulative emissions but is tightly aligned with peak rates of emissions. Hence, cumulative carbon emissions to 2200 and peak emission rates could provide a clear and simple framework for CO(2) mitigation policy. PMID:21115512

Bowerman, Niel H A; Frame, David J; Huntingford, Chris; Lowe, Jason A; Allen, Myles R

2011-01-13

89

A study on the impact of nuclear power plant construction relative to decommissioning Fossil Fuel Power Plant in order to reduce carbon dioxide emissions using a modified Nordhaus Vensim DICE model  

NASA Astrophysics Data System (ADS)

The current levels of CO2 emissions and high levels accumulating in the atmosphere have climate scientists concerned. The Dynamic Integrated Climate Economy Model or "DICE" for short is a highly developed model that has been used to simulate climate change and evaluate factors addressing global warming. The model was developed by Yale's Nordhaus along with collaborators and the compilation of numerous scientific publications. The purpose of this study is to recreate DICE using Vensim and modify it to evaluate the use of nuclear power plants (NPPs) as a means to counter global temperature increases in the atmosphere and oceans and the associated cost of damages. The amount of greenhouse gas emissions from a NPP are about 6% per Megawatt as that from a Fossil Fuel Power Plant (FFPP). Based on this, a model was developed to simulate construction of NPPs with subsequent decommissioning of FFPPs with an equivalent power output. The results produced through multiple simulation runs utilizing variable NPP construction rates show that some minor benefit is achievable if all of the more than 10,000 FFPPs currently in operation in the U.S. are replaced with NPPs. The results show that a reduction in CO 2 emissions of 2.48% will occur if all of the FFPPs are decommissioned. At a minimum rate of 50 NPPs constructed per year, the largest reduction in CO2 in the atmosphere, 1.94% or 44.5 billion tons of carbon, is possible. This results in a reduction in global warming of 0.068C or 1.31%. The results also show that this reduction in global warming will be equivalent to a reduction of 8.2% or $148 B in anticipated annual spending as a result of climate change damages. Further results indicate that using NPPs to address climate change will provide a small benefit; ultimately, it will not be enough to reduce CO2 emissions or atmospheric CO 2 to control global warming. The amount of CO2 in the atmosphere is predicted to be 1055 parts per million (ppm) even in the best case scenario, which is well above the current limit of 350 ppm proposed by Hansen et. al.

Colpetzer, Jason Lee

90

The Impact of a Carbon Tax on Economic Growth and Carbon Dioxide Emissions in Ireland  

Microsoft Academic Search

This paper analyses the medium-term effects of a carbon tax on growth and CO2 emissions in Ireland, a small open economy. We find that a double dividend exists if the carbon tax revenue is recycled through reduced income taxes. If the revenue is recycled by giving a lump-sum transfer to households, a double dividend is unlikely. We also determine that

Thomas Conefrey; John FitzGerald; Laura Malaguzzi Valeri; Richard S. J. Tol

2008-01-01

91

Estimating carbon emissions from African wildfires  

Microsoft Academic Search

Africa is a continent dominated by fire. Vegetation fires, occurring naturally or human-ignited as a land management practice, have a long history in the continent's savannah ecosystems. These fires contribute substantially to the total carbon emissions (e.g. as CO2, CO, CH4, Volatile Organic Compounds, Black Carbon) over large parts of the continent. Many recent attempts to assess the total area

V. Lehsten; K. J. Tansey; H. Balzter; K. Thonicke; A. Spessa; U. Weber; B. Smith; A. Arneth

2008-01-01

92

Grid Expansion Planning for Carbon Emissions Reduction  

SciTech Connect

There is a need to upgrade and expand electric power transmission and generation to meet specified renewable energy targets and simultaneously minimize construction cost and carbon emissions. Some challenges are: (1) Renewable energy sources have variable production capacity; (2) Deficiency of transmission capacity at desirable renewable generation locations; (3) Need to incorporate models of operations into planning studies; and (4) Prevent undesirable operational outcomes such as negative dispatch prices or curtailment of carbon neutral generation.

Bent, Russell W. [Los Alamos National Laboratory; Toole, Gasper L. [Los Alamos National Laboratory

2012-07-18

93

Treading Lightly Steps Toward Reducing Our Carbon Footprint  

E-print Network

Treading Lightly Steps Toward Reducing Our Carbon Footprint This is one section of The University reducing the UA's carbon footprint. The Facilities Management recycling and waste department supports long

Wong, Pak Kin

94

Low carbon spaces: area-based carbon emission reduction -a scoping study  

E-print Network

carbon emission reductions, but to date most strategic thinking has focused on national policy leversLow carbon spaces: area-based carbon emission reduction - a scoping study 02.06.02 #12;1 Low Carbon Spaces Area-Based Carbon Emission Reduction: A Scoping Study Prepared for the Sustainable Development

95

Demographic change and carbon dioxide emissions.  

PubMed

Relations between demographic change and emissions of the major greenhouse gas carbon dioxide (CO(2)) have been studied from different perspectives, but most projections of future emissions only partly take demographic influences into account. We review two types of evidence for how CO(2) emissions from the use of fossil fuels are affected by demographic factors such as population growth or decline, ageing, urbanisation, and changes in household size. First, empirical analyses of historical trends tend to show that CO(2) emissions from energy use respond almost proportionately to changes in population size and that ageing and urbanisation have less than proportional but statistically significant effects. Second, scenario analyses show that alternative population growth paths could have substantial effects on global emissions of CO(2) several decades from now, and that ageing and urbanisation can have important effects in particular world regions. These results imply that policies that slow population growth would probably also have climate-related benefits. PMID:22784534

O'Neill, Brian C; Liddle, Brant; Jiang, Leiwen; Smith, Kirk R; Pachauri, Shonali; Dalton, Michael; Fuchs, Regina

2012-07-14

96

End-Use Efficiency to Lower Carbon Emissions  

SciTech Connect

Compelling evidence demonstrating the warming trend in global temperatures and the mechanism behind it, namely the anthropogenic emissions of carbon dioxide and other greenhouse gases (GHG), has spurred an international effort to reduce emissions of these gases. Despite improving efficiency of the U.S. economy in terms of energy cost per dollar of GDP since the signing of the Kyoto Protocol, energy consumption and carbon emissions are continuing to rise as the economy expands. This growing gap further emphasizes the importance of improving energy use efficiency as a component in the U.S. climate change mitigation program. The end-use efficiency research activities at Berkeley Lab incorporate residential, commercial, industrial, and transportation sectors. This paper focuses on two successful U.S. programs that address end-use efficiency in residential and commercial demand: energy efficient performance standards established by the Department of Energy (DOE) and the Environmental Protection Agency's (EPA's) ENERGY STAR(registered trademark) program.

Marnay, Chris; Osborn, Julie; Webber, Carrie

2001-03-01

97

Policy Planning to Reduce Greenhouse Gas Emissions  

NSDL National Science Digital Library

Preceded by the State Workbook: Methodologies for Estimating Greenhouse Gas Emissions, this document by the Environmental Protection Agency (EPA) serves to guide states in "identifying and evaluating options to mitigate emissions" affecting global climate change. Each of the report's three parts details climate change and policy options. Part one discusses the Initiation of Climate Change Programs. Part two describes sources of emissions and potential policy options. Part three completes the report by offering "guidance in preparing the State Action Plan." Appendices supply a glossary, references, state plans, and a specific example reduction plan.

Agency., United S.

1998-01-01

98

The Land Use Planning Imperative: Applying Carbon Emissions Analyses  

NASA Astrophysics Data System (ADS)

Reversing global warming is the defining crisis of the 21st century and must be dealt with, in part, by reinventing the built environment. Current land use and planning frameworks are not aligned with scientific models which can aid in the reversal of carbon emissions at the local and regional scale. The disjunction between land use planning and the scientific methodologies for calculating the impacts of climate change beg for a stronger union between climate change science and land use planning. Buildings account for approximately 35 percent of the U.S. carbon emissions while the transportation sector accounts for approximately 27 percent (U.S. Department of Energy, Energy Information Administration, United States Environmental Protection Agency, 2007). To adopt energy efficiency measures and hence reduce carbon dioxide emissions at a site, city, or regional scale, land use planners and climate scientists must integrate their expertise to influence policy with precision and accuracy. Land use planners have influence over the design of the built environment in municipalities and institutions such as colleges and universities. In many ways, college and university campuses are microcosms of the land use patterns established historically; they demonstrate a lack of coordinated land use planning across the entire continent that is extremely dependent on the automobile and fossil fuels. Climate models predict that the average temperature at the Earth's surface could increase from 2.5 to 10.4F above 1990 levels by the end of this century (United States Environmental Protection Agency, 2007). Further, it is estimated that the country will have to construct an additional 213 billion square feet of built space by the year 2030 to accommodate the increasing population. Planning and design will dictate the degree to which land use change will exacerbate trends of global warming. It commands an integration of the methodology to calculate carbon emissions with the science which demonstrates the impact of those emissions. This session presents a new approach and methodology for integrating calculating carbon emissions and land use planning to increase the accessibility of carbon dioxide emissions data, transforming our conception of how the built environment can function in a more sustainable way. The emergence of the public and institutional interest in reducing carbon emissions advances the question of how climate science may be applied and translated for a public audience to develop effective, measurable carbon reduction strategies. Building on the growing momentum in the higher education sector in the United States, land use planners are grappling with the integration of carbon reduction and the transformation of the built environment, particularly at college campuses. A critical first step in reducing carbon emissions is to complete a greenhouse gas inventory. In recent years, universities have adopted challenges to become climate neutral through operations, buildings, and transportation. This session will present two case studies at universities of how land use planning integrates scientific data and suggested methodology from the IPCC, the Chicago Climate Exchange, the Kyoto Protocol, and various other climate action registries in order to demonstrate a university's contribution to global warming. By developing a methodology for calculating CO2 emissions, land use planning and climate science can collectively formulate strategies for a more sustainable future.

Bray, E. N.; Havens, G.

2007-12-01

99

Predator-induced reduction of freshwater carbon dioxide emissions  

NASA Astrophysics Data System (ADS)

Predators can influence the exchange of carbon dioxide between ecosystems and the atmosphere by altering ecosystem processes such as decomposition and primary production, according to food web theory. Empirical knowledge of such an effect in freshwater systems is limited, but it has been suggested that predators in odd-numbered food chains suppress freshwater carbon dioxide emissions, and predators in even-numbered food chains enhance emissions. Here, we report experiments in three-tier food chains in experimental ponds, streams and bromeliads in Canada and Costa Rica in the presence or absence of fish (Gasterosteus aculeatus) and invertebrate (Hesperoperla pacifica and Mecistogaster modesta) predators. We monitored carbon dioxide fluxes along with prey and primary producer biomass. We found substantially reduced carbon dioxide emissions in the presence of predators in all systems, despite differences in predator type, hydrology, climatic region, ecological zone and level of in situ primary production. We also observed lower amounts of prey biomass and higher amounts of algal and detrital biomass in the presence of predators. We conclude that predators have the potential to markedly influence carbon dioxide dynamics in freshwater systems.

Atwood, Trisha B.; Hammill, Edd; Greig, Hamish S.; Kratina, Pavel; Shurin, Jonathan B.; Srivastava, Diane S.; Richardson, John S.

2013-03-01

100

Tracing fuel component carbon in the emissions from diesel engines  

NASA Astrophysics Data System (ADS)

The addition of oxygenates to diesel fuel can reduce particulate emissions, but the underlying chemical pathways for the reductions are not well understood. While measurements of particulate matter (PM), unburned hydrocarbons (HC), and carbon monoxide (CO) are routine, determining the contribution of carbon atoms in the original fuel molecules to the formation of these undesired exhaust emissions has proven difficult. Renewable bio-derived fuels (ethanol or bio-diesel) containing a universal distribution of contemporary carbon are easily traced by accelerator mass spectrometry (AMS). These measurements provide general information about the emissions of bio-derived fuels. Another approach exploits synthetic organic chemistry to place 14C atoms in a specific bond position in a specific fuel molecule. The highly labeled fuel molecule is then diluted in 14C-free petroleum-derived stock to make a contemporary petroleum fuel suitable for tracing. The specific 14C atoms are then traced through the combustion event to determine whether they reside in PM, HC, CO, CO2, or other emission products. This knowledge of how specific molecular structures produce certain emissions can be used to refine chemical-kinetic combustion models and to optimize fuel composition to reduce undesired emissions. Due to the high sensitivity of the technique and the lack of appreciable 14C in fossil fuels, fuels for AMS experiments can be labeled with modern levels of 14C and still produce a strong signal. Since the fuel is not radioactive, emission tests can be conducted in any conventional engine lab, dynamometer facility, or on the open road.

Buchholz, Bruce A.; Mueller, Charles J.; Martin, Glen C.; Cheng, A. S.; Dibble, Robert W.; Frantz, Brian R.

2004-08-01

101

Techniques to reduce the emissions from existing woodburning appliances  

SciTech Connect

Over the past few years, it has become widely recognized that wood stoves can produce high levels of incomplete combustion products. In some areas, wood smoke is one of the most serious air pollution sources. Indeed, Whitehorse, in Canada's Yukon Territory, has one of the highest levels of air pollution due to wood stoves in North America. Most efforts to date, both from the technical and the regulatory side, have concentrated on developing new, cleaner burning appliances. While this approach is commendable and is resulting in a number of cleaner, more efficient appliances on the market today, the majority of wood stoves installed in homes in North America are of the older, inferior combustion type. To compound the problem, many people have bought stoves that were too large for their needs, following the adage that bigger is better. This often results in the homeowner reducing the firing rate by closing the air supply, to avoid overheating the house, making the combustion even worse. That most stoves have been installed in the past eight years or less makes the probability of their replacement in the near term unlikely. Unless retrofit technologies or use control strategies are applied in an effective manner, the emissions from wood stoves will be with us for a long time to come. This paper discusses some reduction in emission levels possible through consumer education in proper stove operating procedures. The paper also discusses changes to the hardware, which allow upgrading of existing equipment and means of reducing emissions from existing stoves, through general consumer acceptance. The specific retrofit technique examined in detail for this paper was the use of a retrofit add-on catalyst to react some of the incomplete combustion products, specifically hydrocarbons and carbon monoxide, which would otherwise condense to form creosote in the flue or be released as undesirable pollutants to the atmosphere.

Hayden, A.C.S.; Braaten, R.W. (Canadian Combustion Research Lab., Ottawa (CA))

1988-01-01

102

The environmental cost of reducing agricultural fine particulate matter emissions.  

PubMed

The U.S. Environmental Protection Agency (EPA) revised the National Ambient Air Quality Standards (NAAQS) in 2006, reducing acceptable fine particulate matter (PM2.5) levels; state environmental protection agencies in states with nonattainment areas are required to draft State Implementation Plans (SIPs) detailing measures to reduce regional PM2.5 levels by reducing PM2.5 and PM2.5 precursor emissions. These plans need to account for increases in emissions caused by operating control technologies. Potential PM2.5 emissions reductions realized by adding a second set of dust cyclones were estimated for the cotton ginning industry. Increases in energy consumption were calculated based on dust cyclone air pressure drop. Additional energy required was translated into increased emissions using published emission factors and state emissions inventories. Reductions in gin emissions were compared with increases in emissions at the power plant. Because of the electrical energy required, reducing one unit of agricultural PM2.5 emissions at a cotton gin results in emitting 0.11-2.67 units of direct PM2.5, 1.39-69.1 units of PM2.5 precursors, 1.70-76.8 units of criteria pollutants, and 692-15,400 units of greenhouse gases at the point where electricity is produced. If regulations designed to reduce rural PM2.5 emissions increase electrical power consumption, the unintended net effect may be more emissions, increased environmental damage, and a greater risk to public health. PMID:20564993

Funk, Paul A

2010-06-01

103

Reduced Turbine Emissions Using Hydrogen-Enriched Fuels  

E-print Network

-heating value fuels containing H2 can provide significant source of cost-effective fuels for gas turbines emissions Source: Analysis of Strategies for Reducing Multiple Emissions from Power Plants: Sulfur Dioxide-characterized boundary and flow conditions · Quantify effects of H2 addition on flame stability and emissions · Leverage

104

Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH1 and CRASH2 clinical trials  

Microsoft Academic Search

BACKGROUND: All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. METHODS: We conducted a

Saleena Subaiya; Euan Hogg; Ian Roberts

2011-01-01

105

Utilizing intake-air oxygen-enrichment technology to reduce cold- phase emissions  

SciTech Connect

Oxygen-enriched combustion is a proven, serious considered technique to reduce exhaust hydrocarbons (HC) and carbon monoxide (CO) emissions from automotive gasoline engines. This paper presents the cold-phase emissions reduction results of using oxygen-enriched intake air containing about 23% and 25% oxygen (by volume) in a vehicle powered by a spark-ignition (SI) engine. Both engineout and converter-out emissions data were collected by following the standard federal test procedure (FTP). Converter-out emissions data were also obtained employing the US Environmental Protection Agency`s (EPA`s) ``Off-Cycle`` test. Test results indicate that the engine-out CO emissions during the cold phase (bag 1) were reduced by about 46 and 50%, and HC by about 33 and 43%, using nominal 23 and 25% oxygen-enriched air compared to ambient air (21% oxygen by volume), respectively. However, the corresponding oxides of nitrogen (NO{sub x}) emissions were increased by about 56 and 79%, respectively. Time-resolved emissions data indicate that both HC and CO emissions were reduced considerably during the initial 127 s of the cold-phase FTP, without any increase in NO, emissions in the first 25 s. Hydrocarbon speciation results indicate that all major toxic pollutants, including ozone-forming specific reactivity factors, such as maximum incremental reactivity (NUR) and maximum ozone incremental reactivity (MOIR), were reduced considerably with oxygen-enrichment. Based on these results, it seems that using oxygen-enriched intake air during the cold-phase FTP could potentially reduce HC and CO emissions sufficiently to meet future emissions standards. Off-cycle, converter-out, weighted-average emissions results show that both HC and CO emissions were reduced by about 60 to 75% with 23 or 25% oxygen-enrichment, but the accompanying NO{sub x}, emissions were much higher than those with the ambient air.

Poola, R.B.; Ng, H.K.; Sekar, R.R. [Argonne National Lab., IL (United States); Baudino, J.H. [Autoresearch Labs., Inc., Chicago, IL (United States); Colucci, C.P. [National Renewable Energy Lab., Golden, CO (United States)

1995-12-31

106

Increasing efficiency, reducing emissions with hydrous ethanol in diesel engines  

E-print Network

Increasing efficiency, reducing emissions with hydrous ethanol in diesel engines Ethanol continued, but it can also result in reduced emissions of nitrogen oxides (NOx) and soot when used in diesel engines. ct & LOGISTICS SYMPOSIUM page 3 CIVIL ENGINEERING DIRECTIONS page 4 WORK-ZONE SAFETY page 5 PUBLIC AFFAIRS PH

Minnesota, University of

107

Plasma ignition system reduces NOx emissions  

Microsoft Academic Search

Recent revisions of the Clean Air Act have mandated increasingly stringent controls on nitrogen oxides (NOx) emissions. It is of prime importance that any natural gas pipeline facility consider how to operate in compliance in any regulated area. Plasma ignition control technology has been installed on over 85 compressor engines to date. Using the Superior engine has a new application

1995-01-01

108

REFORMULATING BIODIESEL TO REDUCE NOX EMISSIONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The use of biodiesel, a diesel engine fuel produced from agriculturally derived fats and oils, offers many advantages over petrodiesel, but has been shown in certain instances to increase emissions of oxides of nitrogen (NOx), a federally regulated pollutant. The work described here involved modifi...

109

Could reducing fossil-fuel emissions cause global warming?  

NASA Astrophysics Data System (ADS)

WHEN fossil fuel is burned, both carbon dioxide and sulphur dioxide are added to the atmosphere. The former should cause warming of the lower atmosphere by enhancing the greenhouse effect, whereas the latter, by producing sulphate aerosols, may cause a cooling effect. The possibility that these two processes could offset each other was suggested many years ago (see, for example, ref. 1), but during most of the intervening period, attention has focused on the greenhouse effect. Interest in tropospheric aerosols has, however, recently been rekindled by the realization that they may influence climate, not only through clear-sky radiative effects2-5, but also by modifying cloud albedo6-8. Here I examine the sensitivity of the climate system to simultaneous changes in SO2 and CO2 emissions, as might occur if controls were imposed on fossil-fuel use. Over the next 10-30 years, it is conceivable that the increased radiative forcing due to SO2 concentration changes could more than offset reductions in radiative forcing due to reduced CO2 emissions.

Wigley, T. M. L.

1991-02-01

110

The role of nuclear energy in reducing U.S. and global greenhouse gas emissions  

SciTech Connect

This paper presents a perspective on the role that nuclear energy is playing worldwide and in the US towards reducing emissions of greenhouse gases, particularly carbon dioxide. In playing a key part in the nation`s electrification over the past 20 years, nuclear energy has also been critical in reducing electric utility greenhouse gas and other atmospheric emissions. In the context of the administration`s Climate Change Action Plan, the improved performance of US nuclear power plants will be the single major contributor towards meeting the year 2000 goal of stabilizing the nation`s greenhouse gas emissions to their 1990 levels.

Fertel, M.S. [Nuclear Economics and Fuel Supply, Washington, DC (United States); Johnson, S.M. [Nuclear Energy Institute, Washington, DC (United States)

1995-12-31

111

Using advanced technologies to reduce motor vehicle greenhouse gas emissions  

Microsoft Academic Search

This paper quantifies the potential reduction in US greenhouse gas emissions that could be achieved by using advanced-technology motor vehicles and low-emission bio-fuels. These two approaches are compared to a variety of other approaches to reduce transportation sector emissions. It is concluded that only strong fiscal measures can produce emission reductions as large as are available from advanced-technology vehicles and

Carmen Difiglio

1997-01-01

112

Subsurface manure application to reduce ammonia emissions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Incorporation into soil is generally recommended to reduce ammonia volatilization and nutrient runoff following land application of manures. A range of subsurface applicators are available for manure incorporation with minimal soil disturbance in reduced tillage systems, but none have been widely a...

113

Estimating carbon emissions from African wildfires  

NASA Astrophysics Data System (ADS)

We developed a technique for studying seasonal and interannual variation in pyrogenic carbon emissions from Africa using a modelling approach that scales burned area estimates from L3JRC, a map recently generated from remote sensing of burn scars instead of active fires. Carbon fluxes were calculated by the novel fire model SPITFIRE embedded within the dynamic vegetation model framework LPJ-GUESS, using daily climate input. For the time period from 2001 to 2005 an average area of 195.524104 km2 was burned annually, releasing an average of 72370 Tg C to the atmosphere; these estimates for the biomass burned are within the range of previously published estimates. Despite the fact that the majority of wildfires are ignited by humans, strong relationships between climatic conditions (particularly precipitation), net primary productivity and overall biomass burnt emerged. Our investigation of the relationships between burnt area and carbon emissions and their potential drivers available litter and precipitation revealed uni-modal responses to annual precipitation, with a maximum around 1000 mm for burned area and emissions, or 1200 mm for litter availability. Similar response patterns identified in savannahs worldwide point to precipitation as a chief determinant for short-term variation in fire regime. A considerable variability that cannot be explained by fire-precipitation relationships alone indicates the existence of additional factors that must be taken into account.

Lehsten, V.; Tansey, K.; Balzter, H.; Thonicke, K.; Spessa, A.; Weber, U.; Smith, B.; Arneth, A.

2009-03-01

114

Carbon emission targets for driving sustainable mobility with US light-duty vehicles.  

PubMed

Models and frameworks to guide "sustainable mobility" of personal transportation lack definitive quantitative targets. This paper defines sustainable mobility targets for US light-duty vehicles (LDVs) to help stabilize atmospheric carbon dioxide concentrations at 450 or 550 ppm. The Intergovernmental Panel on Climate Change carbon stabilization pathways are used to equitably distribute future carbon dioxide emissions to the US. Allowable US emissions are then allocated to the LDV sector according to the current share of national emissions. Average on-road LDV well-to-wheel carbon emissions must be reduced from 160 g/mile (2002) to 20 g/mile by 2050 to contribute to a 450 ppm CO2 goal. Strategies to reduce LDV greenhouse gas emissions include reducing travel demand, improving average fuel economy, and utilizing low-carbon ethanol. Simulations using EIA modeling parameters indicate that average LDV fuel economy must reach 136 mpg, cellulosic ethanol must make up over 83% of fuel market share, or annual LDV travel demand must be reduced by about 53% by 2050 to help meet LDV greenhouse gas targets based on a 450 ppm CO2 stabilization goal. Recent federal energy security policy and plug-in hybrid technology programs may also help meet LDV carbon emission targets in the short term by reducing gasoline use, but an aggressive combination of strategies will be needed to keep vehicle CO2 in line with an emissions target to 2050. PMID:19244987

Grimes-Casey, Hilary G; Keoleian, Gregory A; Willcox, Blair

2009-02-01

115

Nitrogen and phosphorous limitations significantly reduce future allowable CO2 emissions  

NASA Astrophysics Data System (ADS)

Earth System Models (ESMs) can be used to diagnose the emissions of CO2 allowed in order to follow the representative concentration pathways (RCPs) that are consistent with different climate scenarios. By mass balance, the allowable emission is calculated as the sum of the changes in atmospheric CO2, land and ocean carbon pools. Only two ESMs used in the fifth assessment (AR5) of International Panel on Climate Change (IPCC) include nitrogen (N) limitation, and none include phosphorous (P) limitation. In this study we quantified the effects of N and P limitations on the allowable emissions using an ESM simulating land and ocean CO2 exchanges to the atmosphere in RCPs used for IPCC AR5. The model can run with carbon cycle alone (C only), carbon and nitrogen (CN) or carbon, nitrogen and phosphorus (CNP) cycles as its land configurations. We used the simulated land and ocean carbon accumulation rates from 1850 to 2100 to diagnose the allowable emissions for each of three simulations (C only, CN or CNP). These were then compared with the emissions estimated by the Integrated Assessment Models (IAMs) used to generate RCP2.6 and RCP8.5. N and P limitations on land in our ESM led to systematically lower land carbon uptake, and thus reduced allowable emissions by 69 Pg C (21%) for RCP2.6, and by 250 Pg C (13%) for RCP8.5 from 2006 to 2100. Our results demonstrated that including N and P limitations requires a greater reduction in human CO2 emissions than assumed in the IAMs used to generate the RCPs. Reference: Zhang, Q., Y. P. Wang, R. J. Matear, A. J. Pitman, and Y. J. Dai (2014), Nitrogen and phosphorous limitations significantly reduce future allowable CO2 emissions, Geophys. Res. Lett., 41, doi:10.1002/2013GL058352.

Zhang, Qian; Wang, Ying-Ping; Matear, Richard; Pitman, Andy; Dai, Yongjiu

2014-05-01

116

Hydration of Gases to Reduce Major Greenhouse Gases Emission into the Atmosphere  

Microsoft Academic Search

A technology on replacement methane (CH4) from natural gas hydrate (NGH) with carbon dioxide (CO2) is described. And the technology is demonstrated in theoretics and experiment, respectively. Moreover, combined with the main emission channel of CH4 in coal industry, the reducing emission technology of coalbed methane(CBM) based on hydration is narrated. The formation and dissociation technique of CH4 hydrates are

Xu Feng; Zhu Lihua; Wu Qiang

2009-01-01

117

The 11 Micron Emissions of Carbon Stars  

NASA Technical Reports Server (NTRS)

A new classification scheme of the IRAS LRS carbon stars is presented. It comprises the separation of 718 probable carbon stars into 12 distinct self-similar spectral groupings. Continuum temperatures are assigned and range from 470 to 5000 K. Three distinct dust species are identifiable: SiC, alpha:C-H, and MgS. In addition to the narrow 11 + micron emission feature that is commonly attributed to SiC, a broad 11 + micron emission feature, that is correlated with the 8.5 and 7.7 micron features, is found and attributed to alpha:C-H. SiC and alpha:C-H band strengths are found to correlate with the temperature progression among the Classes. We find a spectral sequence of Classes that reflects the carbon star evolutionary sequence of spectral types, or alternatively developmental sequences of grain condensation in carbon-rich circumstellar shells. If decreasing temperature corresponds to increasing evolution, then decreasing temperature corresponds to increasing C/O resulting in increasing amounts of carbon rich dust, namely alpha:C-H. If decreasing the temperature corresponds to a grain condensation sequence, then heterogeneous, or induced nucleation scenarios are supported. SiC grains precede alpha:C-H and form the nuclei for the condensation of the latter material. At still lower temperatures, MgS appears to be quite prevalent. No 11.3 micron PAH features are identified in any of the 718 carbon stars. However, one of the coldest objects, IRAS 15048-5702, and a few others, displays an 11.9 micron emission feature characteristic of laboratory samples of coronene. That feature corresponds to the C-H out of plane deformation mode of aromatic hydrocarbon. This band indicates the presence of unsaturated, sp(sup 3), hydrocarbon bonds that may subsequently evolve into saturated bonds, sp(sup 2), if, and when, the star enters the planetary nebulae phase of stellar evolution. The effusion of hydrogen from the hydrocarbon grain results in the evolution in wavelength of this 11.9 micron emission feature to the 11.3 micron feature.

Goebel, J. H.; Cheeseman, P.; Gerbault, F.

1995-01-01

118

U.S. Energy-Related Carbon Dioxide Emissions  

EIA Publications

U.S. Energy Information Administration releases its online analysis of 2012 energy-related carbon dioxide emissions today. It indicates U.S. carbon dioxide emissions from the consumption of fossil fuels were 5,290 million metric tons carbon dioxide in 2012, a decrease of almost 4% from the 2011 level. Energy-related carbon dioxide emissions have declined in five of the last seven years and are the lowest they have been since 1994.

2014-01-01

119

Pilot study to reduce emissions, improve health, and offset BC emissions through the distribution of improved cook stoves in Nepal  

NASA Astrophysics Data System (ADS)

In most developing countries, wood and other biomass fuels are still the primary source of energy for the majority of the people, particularly the poor. It is estimated that cook stoves account for approximately 20% of global black carbon emissions. In Nepal 87% of energy is supplied from traditional biomass and 75% of households still depend on biomass as a cooking fuel. The substitution of traditional cook stoves with improved cook stoves provides an important way to reduce black carbon emissions. In 2013 the International Centre for Integrated Mountain Development (ICIMOD) has commenced a pilot study that both examines ways to effectively disseminate improved cookstoves across remote rural mountain regions, and also quantifies the resulting changes in emissions, air quality and health. The selected study area is in Bajrabarahi Village in Makawanpur district, to the southwest of Kathmandu. The study area consists of around 1600 households, which are divided into control groups and groups where the cook stove intervention is taking place. The study complements the ';Clean Cooking energy solution for all by 2017' announced by the Government of Nepal recently, and will provide insights to the government on ways to effectively reduce black carbon emissions from cook stoves. To make the study robust and sustainable, local women's group and a local medical institution are involved in the project right from the conceptualization stage. The study region has been chosen in part because the medical school Patan Academy of Health Sciences (PAHS) has already started a long term health assessment in the region, and has built up considerable local contacts. The local women's group is working on the modality of cook stove distribution through micro credit programmes in the village. We will distribute the best available manufactured, fan-assisted cook stoves that are expected to reduce BC emissions the most. Health assessments, emissions estimates, as well as measurements of indoor and outdoor air quality will be done before and after the stoves are disseminated. Having obtained funds for the purchase of improved cook stoves from Nepal's diesel automobile sector, we compare the emissions of black carbon from the sponsoring diesel vehicles with the reduction in black carbon emissions from the sponsored improved cook stoves, thereby pioneering methods to offset black carbon emissions.

Banmali Pradhan, B.; Panday, A. K.; Surapipith, V.

2013-12-01

120

Analysis of Strategies for Reducing Multiple Emissions from Electric Power Plants: SO2, Nox, CO2  

EIA Publications

This report responds to a request received from Senator David McIntosh on June 29, 2000 to analyze the impacts on energy consumers and producers of coordinated strategies to reduce emissions of sulfur dioxide, nitrogen oxides, and carbon dioxide at U.S. power plants.

2001-01-01

121

Reduce VOC Emissions from Manufacturing Processes  

Microsoft Academic Search

This paper provides insight of many aspects of reducing VOC approaches geared towards assembly and test factories. With the management supports to take environment excellence to the next level, the Chemical management team working together with factory floor employees has embarked on a journey and impressive results shown passion for environmental effort and poised to set benchmark as future factory

Tan Lin Sheng; M. Z. bin Shamsudin; Loh Chin Ling

2006-01-01

122

PARKING MANAGEMENT STRATEGIES FOR REDUCING AUTOMOBILE EMISSIONS  

EPA Science Inventory

This report defines the concept of parking management and explores how parking management can be used to improve air quality, support mass transit, reduce energy consumption and improve the amenities of life in urban areas. Specific aspects of this analysis were developments of a...

123

Apparatus for reducing solvent luminescence background emissions  

DOEpatents

The detectability of luminescent molecules in solution is enhanced by reducing the background luminescence due to impurity species also present in the solution. A light source that illuminates the solution acts to photolyze the impurities so that the impurities do not luminesce in the fluorescence band of the molecule of interest. Molecules of interest may be carried through the photolysis region in the solution or may be introduced into the solution after the photolysis region.

Affleck, Rhett L. (Los Alamos, NM); Ambrose, W. Patrick (Los Alamos, NM); Demas, James N. (Charlottesville, VA); Goodwin, Peter M. (Jemez Springs, NM); Johnson, Mitchell E. (Pittsburgh, PA); Keller, Richard A. (Los Alamos, NM); Petty, Jeffrey T. (Los Alamos, NM); Schecker, Jay A. (Sante Fe, NM); Wu, Ming (Los Alamos, NM)

1998-01-01

124

Apparatus for reducing solvent luminescence background emissions  

DOEpatents

The detectability of luminescent molecules in solution is enhanced by reducing the background luminescence due to impurity species also present in the solution. A light source that illuminates the solution acts to photolyze the impurities so that the impurities do not luminesce in the fluorescence band of the molecule of interest. Molecules of interest may be carried through the photolysis region in the solution or may be introduced into the solution after the photolysis region. 6 figs.

Affleck, R.L.; Ambrose, W.P.; Demas, J.N.; Goodwin, P.M.; Johnson, M.E.; Keller, R.A.; Petty, J.T.; Schecker, J.A.; Wu, M.

1998-11-10

125

Wood-based building materials and atmospheric carbon emissions  

Microsoft Academic Search

This study investigates the global impact of wood as a building material by considering emissions of carbon dioxide to the atmosphere. Wood is compared with other materials in terms of stored carbon and emissions of carbon dioxide from fossil fuel energy used in manufacturing. An analysis of typical forms of building construction shows that wood buildings require much lower process

Andrew H Buchanan; S. Bry Levine

1999-01-01

126

Status of Technological Advancements for Reducing Aircraft Gas Turbine Engine Pollutant Emissions  

NASA Technical Reports Server (NTRS)

Combustor test rig results indicate that substantial reductions from current emission levels of carbon monoxide (CO), total unburned hydrocarbons (THC), oxides of nitrogen (NOx), and smoke are achievable by employing varying degrees of technological advancements in combustion systems. Minor to moderate modifications to existing conventional combustors produced significant reductions in CO and THC emissions at engine low power (idle/taxi) operating conditions but did not effectively reduce NOx at engine full power (takeoff) operating conditions. Staged combusiton techniques were needed to simultaneously reduce the levels of all the emissions over the entire engine operating range (from idle to takeoff). Emission levels that approached or were below the requirements of the 1979 EPA standards were achieved with the staged combustion systems and in some cases with the minor to moderate modifications to existing conventional combustion systems. Results from research programs indicate that an entire new generation of combustor technology with extremely low emission levels may be possible in the future.

Rudey, R. A.

1975-01-01

127

Upscaling carbon dioxide emissions from lakes  

NASA Astrophysics Data System (ADS)

CO2 fluxes from lakes to the atmosphere is important for balancing regional and global-scale carbon budgets. CO2 emissions are estimated through statistical upscaling procedures that aggregate data from a large number of lakes. However, aggregation can bias flux estimates if the physical and chemical factors determining CO2 exchange between water and the atmosphere are not independent. We evaluated the magnitude of aggregation biases with moment expansions and pCO2 data from 5140 Swedish lakes. The direction of the aggregation bias depends on lake size; mean flux was overestimated by 4% for small lakes (0.01-0.1 km2) but underestimated by 13% for large lakes (100-1000 km2). Simple covariance-based correction factors were generated to adjust for upscaling biases. These correction factors represent an easily interpretable and implemented approach to improving the accuracy of regional and global estimates of lake CO2 emissions.

Seekell, David A.; Carr, Joel A.; Gudasz, Cristian; Karlsson, Jan

2014-11-01

128

Field emission of aligned grown carbon nanotubes  

NASA Astrophysics Data System (ADS)

Tungsten carbide/cobalt hard metals were coated with multi-walled carbon nanotubes (CNT) using microwave assisted chemical vapor deposition (MWCVD). The aspect ratio of the tubes and their packing density were changed by the deposition conditions and by wet-chemical pre-treatments of the substrate surfaces. The influence of the morphology of the nanotube layers on the electron field emission was investigated. The best layers yielded field enhancement factors of 1500 - 2000 and current densities up to 0.1 A/cm2.

Bartsch, Karl; Leonhardt, A.

2003-10-01

129

Light absorbing carbon emissions from commercial shipping  

NASA Astrophysics Data System (ADS)

Extensive measurements of the emission of light absorbing carbon aerosol (LAC) from commercial shipping are presented. Vessel emissions were sampled using a photoacoustic spectrometer in the Gulf of Mexico region. The highest emitters (per unit fuel burnt) are tug boats, thus making significant contributions to local air quality in ports. Emission of LAC from cargo and non cargo vessels in this study appears to be independent of engine load. Shipping fuel consumption data (2001) was used to calculate a global LAC contribution of 133(+/-27) Ggyr-1, or ~1.7% of global LAC. This small fraction could have disproportionate effects on both air quality near port areas and climate in the Arctic if direct emissions of LAC occur in that region due to opening Arctic sea routes. The global contribution of this LAC burden was investigated using the MOZART model. Increases of 20-50 ng m-3 LAC (relative increases up to 40%) due to shipping occur in the tropical Atlantic, Indonesia, central America and the southern regions of South America and Africa.

Lack, Daniel; Lerner, Brian; Granier, Claire; Baynard, Tahllee; Lovejoy, Edward; Massoli, Paola; Ravishankara, A. R.; Williams, Eric

2008-07-01

130

Using Geothermal Electric Power to Reduce Carbon Footprint  

NASA Astrophysics Data System (ADS)

Human activities, including the burning of fossil fuels, increase carbon dioxide levels, which contributes to global warming. The research problem of the current study examined if geothermal electric power could adequately replace fossil fuel by 2050, thus reducing the emissions of carbon dioxide while avoiding potential problems with expanding nuclear generation. The purpose of this experimental research was to explore under what funding and business conditions geothermal power could be exploited to replace fossil fuels, chiefly coal. Complex systems theory, along with network theory, provided the theoretical foundation for the study. Research hypotheses focused on parameters, such as funding level, exploration type, and interfaces with the existing power grid that will bring the United States closest to the goal of phasing out fossil based power by 2050. The research was conducted by means of computer simulations, using agent-based modeling, wherein data were generated and analyzed. The simulations incorporated key information about the location of geothermal resources, exploitation methods, transmission grid limits and enhancements, and demand centers and growth. The simulation suggested that rapid and aggressive deployment of geothermal power plants in high potential areas, combined with a phase out of coal and nuclear plants, would produce minimal disruptions in the supply of electrical power in the United States. The implications for social change include reduced risk of global warming for all humans on the planet, reduced pollution due to reduction or elimination of coal and nuclear power, increased stability in energy supply and prices in the United States, and increased employment of United States citizens in jobs related to domestic energy production.

Crombie, George W.

131

Path independence of climate and carbon cycle response over a broad range of cumulative carbon emissions  

NASA Astrophysics Data System (ADS)

Recent studies have identified an approximately proportional relationship between global warming and cumulative carbon emissions, yet the robustness of this relationship has not been tested over a broad range of cumulative emissions and emission rates. This study explores the path dependence of the climate and carbon cycle response using an Earth system model of intermediate complexity forced with 24 idealized emissions scenarios across five cumulative emission groups (1275-5275 Gt C) with varying rates of emission. We find the century-scale climate and carbon cycle response after cessation of emissions to be approximately independent of emission pathway for all cumulative emission levels considered. The ratio of global mean temperature change to cumulative emissions - referred to as the transient climate response to cumulative carbon emissions (TCRE) - is found to be constant for cumulative emissions lower than ∼1500 Gt C but to decline with higher cumulative emissions. The TCRE is also found to decrease with increasing emission rate. The response of Arctic sea ice is found to be approximately proportional to cumulative emissions, while the response of the Atlantic Meridional Overturning Circulation does not scale linearly with cumulative emissions, as its peak response is strongly dependent on emission rate. Ocean carbon uptake weakens with increasing cumulative emissions, while land carbon uptake displays non-monotonic behavior, increasing up to a cumulative emission threshold of ∼2000 Gt C and then declining.

Herrington, T.; Zickfeld, K.

2014-11-01

132

Urban energy consumption and related carbon emission estimation: a study at the sector scale  

NASA Astrophysics Data System (ADS)

With rapid economic development and energy consumption growth, China has become the largest energy consumer in the world. Impelled by extensive international concern, there is an urgent need to analyze the characteristics of energy consumption and related carbon emission, with the objective of saving energy, reducing carbon emission, and lessening environmental impact. Focusing on urban ecosystems, the biggest energy consumer, a method for estimating energy consumption and related carbon emission was established at the urban sector scale in this paper. Based on data for 1996-2010, the proposed method was applied to Beijing in a case study to analyze the consumption of different energy resources (i.e., coal, oil, gas, and electricity) and related carbon emission in different sectors (i.e., agriculture, industry, construction, transportation, household, and service sectors). The results showed that coal and oil contributed most to energy consumption and carbon emission among different energy resources during the study period, while the industrial sector consumed the most energy and emitted the most carbon among different sectors. Suggestions were put forward for energy conservation and emission reduction in Beijing. The analysis of energy consumption and related carbon emission at the sector scale is helpful for practical energy saving and emission reduction in urban ecosystems.

Lu, Weiwei; Chen, Chen; Su, Meirong; Chen, Bin; Cai, Yanpeng; Xing, Tao

2013-12-01

133

Reducing CO 2 emissions by substituting biomass for fossil fuels  

Microsoft Academic Search

Replacing fossil fuels with sustainably-produced biomass will reduce the net flow of CO2 to the atmosphere. We express the efficiency of this substitution in reduced emissions per unit of used land or biomass and in costs of the substitution per tonne of C. The substitution costs are calculated as the cost difference between continued use of fossil fuels at current

Leif Gustavsson; Pl Brjesson; Bengt Johansson; Per Svenningsson

1995-01-01

134

OPTIMIZATION OF OPERATIONAL AIRCRAFT PARAMETERS REDUCING NOISE EMISSION  

E-print Network

algorithm has solved a complex optimal control problem, and generates flight paths minimizing aircraft noiseOPTIMIZATION OF OPERATIONAL AIRCRAFT PARAMETERS REDUCING NOISE EMISSION LINA ABDALLAH, MOUNIR method to provide flight path optimums reducing aircraft noise in the vicinity of airports. Optimization

d'Orléans, Université

135

Carbon, Nitrogen Balances and Greenhouse Gas Emission during Cattle Feedlot Manure Composting  

Microsoft Academic Search

Carbon and N losses reduce the agronomic value of compost and contribute to greenhouse gas (GHG) emissions. This study investi-gated GHG emissions during composting of straw-bedded manure (SBM) and wood chip-bedded manure (WBM). For SBM, dry matter (DM) loss was 301 kg Mg,, total carbon (TC) loss was 174 kg Mg,, and total nitrogen (TN) loss was 8.3 kg Mg,.

Xiying Hao; Chi Chang; Francis J. Larney

2004-01-01

136

A synthesis of carbon dioxide emissions from fossil-fuel combustion  

SciTech Connect

This synthesis discusses the emissions of carbon dioxide from fossil-fuel combustion and cement production. While much is known about these emissions, there is still much that is unknown about the details surrounding these emissions. This synthesis explores 5 our knowledge of these emissions in terms of why there is concern about them; how they are calculated; the major global efforts on inventorying them; their global, regional, and national totals at different spatial and temporal scales; how they are distributed on global grids (i.e. maps); how they are transported in models; and the uncertainties associated with these different aspects of the emissions. The magnitude of emissions 10 from the combustion of fossil fuels has been almost continuously increasing with time since fossil fuels were first used by humans. Despite events in some nations specifically designed to reduce emissions, or which have had emissions reduction as a byproduct of other events, global total emissions continue their general increase with time. Global total fossil-fuel carbon dioxide emissions are known to within 10% uncertainty (95% 15 confidence interval). Uncertainty on individual national total fossil-fuel carbon dioxide emissions range from a few percent to more than 50 %. The information discussed in this manuscript synthesizes global, regional and national fossil-fuel carbon dioxide emissions, their distributions, their transport, and the associated uncertainties.

Andres, Robert Joseph [ORNL; Boden, Thomas A [ORNL; Breon, F.-M. [CEA/DSM/LSCE, Gif sur Yvette, France; Ciais, P. [LSCE/CEA, Gif-sur-Yvette, France; Davis, S. [Carnegie Institution of Washington; Erickson, D [Oak Ridge National Laboratory (ORNL); Gregg, J. S. [Riso National Laboratory, Roskilde, Denmark; Jacobson, Andrew [NOAA ESRL and CIRES; Marland, Gregg [Appalachian State University; Miller, J. [NOAA ESRL and CIRES; Oda, T [NOAA ESRL/Boulder, CO/Cooperative Institute for Research in the Atmosphere, Colorado State Univ.; Oliver, J. G. J. [PBL Netherlands Environmental Assessment Agency, Bilthoven, The Netherlands; Raupach, Michael [CSIRO Marine and Atmospheric Research; Rayner, P [University of Melbourne, Australia; Treanton, K. [Energy Statistics Division, International Energy Agency, Paris, France

2012-01-01

137

[Monitoring gas concentration from carbon emissions by remote sensing].  

PubMed

Global climate warming has become the focus question of international global climate change research, and is an important factor influencing world economy, political situation, and ecological environment. Produced carbon emission gases such as CO2, CH4, N2O, etc. caused by human activity are the main reason for global warming. In order to forecast future climate change and construct accurate carbon cycle model, monitoring accuracy of gas concentration from carbon emission must be improved. In the present paper, the newest progress in the international research results about monitoring gas concentration from carbon emissions by remote sensing was considered, monitoring method for carbon emissions was introduced, and remotely sensed monitoring technology about gas concentration from carbon emissions (including thermal infrared, sun spectrum, active remote sensing monitoring technology) was stated. In detail, several present and future satellite sensors were introduced (including TOVS, AIRS, IASI, SCIAMACHY, GOSAT, OCO, A-SCOPE and ASCENDS), and monitoring results achieved by these sensors were analyzed. PMID:22870656

Wang, Li-Wen; Wei, Ya-Xing

2012-06-01

138

Reducing CO2 emissions and energy consumption of heat-integrated distillation systems.  

PubMed

Distillation systems are energy and power intensive processes and contribute significantly to the greenhouse gases emissions (e.g. carbon dioxide). Reducing CO2 emissions is an absolute necessity and expensive challenge to the chemical process industries in orderto meetthe environmental targets as agreed in the Kyoto Protocol. A simple model for the calculation of CO2 emissions from heat-integrated distillation systems is introduced, considering typical process industry utility devices such as boilers, furnaces, and turbines. Furnaces and turbines consume large quantities of fuels to provide electricity and process heats. As a result, they produce considerable amounts of CO2 gas to the atmosphere. Boilers are necessary to supply steam for heating purposes; besides, they are also significant emissions contributors. The model is used in an optimization-based approach to optimize the process conditions of an existing crude oil atmospheric tower in order to reduce its CO2 emissions and energy demands. It is also applied to generate design options to reduce the emissions from a novel internally heat-integrated distillation column (HIDiC). A gas turbine can be integrated with these distillation systems for larger emissions reduction and further energy savings. Results show that existing crude oil installations can save up to 21% in energy and 22% in emissions, when the process conditions are optimized. Additionally, by integrating a gas turbine, the total emissions can be reduced further by 48%. Internal heat-integrated columns can be a good alternative to conventional heat pump and other energy intensive close boiling mixtures separations. Energy savings can reach up to 100% with respect to reboiler heat requirements. Emissions of these configurations are cut down by up to 83%, compared to conventional units, and by 36%, with respect to heat pump alternatives. Importantly, cost savings and more profit are gained in parallel to emissions minimization. PMID:16190250

Gadalla, Mamdouh A; Olujic, Zarko; Jansens, Peter J; Jobson, Megan; Smith, Robin

2005-09-01

139

Development of air conditioning technologies to reduce CO2 emissions in the commercial sector  

PubMed Central

Background Architectural methods that take into account global environmental conservation generally concentrate on mitigating the heat load of buildings. Here, we evaluate the reduction of carbon dioxide (CO2) emissions that can be achieved by improving heating, ventilating, and air conditioning (HVAC) technologies. Results The Climate Change Research Hall (CCRH) of the National Institute for Environmental Studies (NIES) is used as a case study. CCRH was built in line with the "Green Government Buildings" program of the Government Buildings Department at the Ministry of Land, Infrastructure and Transport in Japan. We have assessed the technology used in this building, and found that there is a possibility to reduce energy consumption in the HVAC system by 30%. Conclusion Saving energy reduces CO2 emissions in the commercial sector, although emission factors depend on the country or region. Consequently, energy savings potential may serve as a criterion in selecting HVAC technologies with respect to emission reduction targets. PMID:17062161

Yoshida, Yukiko

2006-01-01

140

The challenges of reducing greenhouse gas emissions and air pollution through energy sources: evidence from a panel of developed countries.  

PubMed

The objective of the study is to investigate the long-run relationship between climatic factors (i.e., greenhouse gas emissions, agricultural methane emissions, and industrial nitrous oxide emission), air pollution (i.e., carbon dioxide emissions), and energy sources (i.e., nuclear energy; oil, gas, and coal energy; and fossil fuel energy) in the panel of 35 developed countries (including EU-15, new EU member states, G-7, and other countries) over a period of 1975-2012. In order to achieve this objective, the present study uses sophisticated panel econometric techniques including panel cointegration, panel fully modified OLS (FMOLS), and dynamic OLS (DOLS). The results show that there is a long-run relationship between the variables. Nuclear energy reduces greenhouse gases and carbon emissions; however, the other emissions, i.e., agricultural methane emissions and industrial nitrous oxide, are still to increase during the study period. Electricity production from oil, gas, and coal sources increases the greenhouse gases and carbon emissions; however, the intensity to increase emissions is far less than the intensity to increase emissions through fossil fuel. Policies that reduce emissions of greenhouse gases can simultaneously alter emissions of conventional pollutants that have deleterious effects on human health and the environment. PMID:24584642

Akhmat, Ghulam; Zaman, Khalid; Shukui, Tan; Sajjad, Faiza; Khan, Muhammad Azhar; Khan, Muhammad Zahir

2014-06-01

141

In Brief: Reducing ship emissions along U.S. coastline  

NASA Astrophysics Data System (ADS)

The United States has called for reducing harmful ship emissions by asking the International Maritime Organization (IMO), a United Nations agency, to create a 370-kilometer-wide emissions control area (ECA) around the U.S. coastline, the U.S. Environmental Protection Agency (EPA) announced on 30 March. IMO will begin reviewing the proposal in July, and approval could occur as early as next year. According to EPA, by 2020 the ECA would save up to 8300 American and Canadian lives every year by imposing stricter standards on oil tankers and other large ships. Under this program, large ships that operate in ECAs would face stricter emissions standards that would cut sulfur in fuel by 98%, particulate matter emissions by 85%, and nitrogen oxide emissions by 80% from the current global requirements.

Showstack, Randy

2009-04-01

142

Decomposition of energy-related carbon emissions in Xinjiang and relative mitigation policy recommendations  

NASA Astrophysics Data System (ADS)

Regional carbon emissions research is necessary and helpful for China in realizing reduction targets. The LMDI I (Logarithmic Mean Divisia Index I) technique based on an extended Kaya identity was conducted to uncover the main five driving forces for energy-related carbon emissions in Xinjiang, an important energy base in China. Decomposition results show that the affluence effect and the population effect are the two most important contributors to increased carbon emissions. The energy intensity effect had a positive influence on carbon emissions during the pre-reform period, and then became the dominant factor in curbing carbon emissions after 1978. The renewable energy penetration effect and the emission coefficient effect showed important negative but relatively minor effects on carbon emissions. Based on the local realities, a comprehensive suite of mitigation policies are raised by considering all of these influencing factors. Mitigation policies will need to significantly reduce energy intensity and pay more attention to the regional economic development path. Fossil fuel substitution should be considered seriously. Renewable energy should be increased in the energy mix. All of these policy recommendations, if implemented by the central and local government, should make great contributions to energy saving and emission reduction in Xinjiang.

Wang, Changjian; Zhang, Xiaolei; Wang, Fei; Lei, Jun; Zhang, Li

2014-06-01

143

Reducing the spin-spin interaction of stable carbon radicals.  

PubMed

We report the discovery that a flow of CO2, N2 or He can sufficiently reduce the spin-spin interactions of specific stable carbon centered radicals by displacing the molecular oxygen in the atmosphere enabling their detection via electron paramagnetic resonance (EPR). This finding unlike other reported effects on carbon radicals occurs under STP conditions and is reversible. PMID:23518921

Green, Uri; Aizenshtat, Zeev; Ruthstein, Sharon; Cohen, Haim

2013-05-01

144

Irreversible climate change due to carbon dioxide emissions  

Microsoft Academic Search

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative

Susan Solomon; Gian-Kasper Plattner; Reto Knutti; Pierre Friedlingstein

2009-01-01

145

Effectiveness of US state policies in reducing CO2 emissions from power plants  

NASA Astrophysics Data System (ADS)

President Obama's landmark initiative to reduce the CO2 emissions of existing power plants, the nation's largest source of greenhouse gas (GHG) pollutants, depends heavily on states and their ability to devise policies that meet the goals set by the Environmental Protection Agency (EPA). Under the EPA's proposed Clean Power Plan, states will be responsible for cutting power plants' carbon pollution 30% from 2005 levels by 2030. States have already adopted several policies to reduce the electricity sector's climate impact. Some of these policies focus on reducing power plants' CO2 emissions, and others address this outcome in a more roundabout fashion by encouraging energy efficiency and renewable energy. However, it remains unclear which, if any, of these direct and indirect strategies actually mitigate plants' emissions because scholars have yet to test their effects using plant-level emission data. Here we use a newly released data source to determine whether states' policies significantly shape individual power plants' CO2 emissions. Findings reveal that certain types of direct strategy (emission caps and GHG targets) and indirect ones (public benefit funds and electric decoupling) lower plants' emissions and thus are viable building blocks of a federal climate regime.

Grant, Don; Bergstrand, Kelly; Running, Katrina

2014-11-01

146

Reducing dust emissions at OAO Alchevskkoks coke battery 10A  

SciTech Connect

Coke battery 10A with rammed batch is under construction at OAO Alchevskkoks. The design documentation developed by Giprokoks includes measures for reducing dust emissions to the atmosphere. Aspiration systems with dry dust trapping are employed in the new components of coke battery 10A and in the existing coke-sorting equipment. Two-stage purification of dusty air in cyclones and bag filters is employed for the coke-sorting equipment. This system considerably reduces coke-dust emissions to the atmosphere.

T.F. Trembach; E.N. Lanina [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

2009-07-15

147

A strategic decision-making model considering the social costs of carbon dioxide emissions for sustainable supply chain management.  

PubMed

Incorporating sustainability into supply chain management has become a critical issue driven by pressures from governments, customers, and various stakeholder groups over the past decade. This study proposes a strategic decision-making model considering both the operational costs and social costs caused by the carbon dioxide emissions from operating such a supply chain network for sustainable supply chain management. This model was used to evaluate carbon dioxide emissions and operational costs under different scenarios in an apparel manufacturing supply chain network. The results showed that the higher the social cost rate of carbon dioxide emissions, the lower the amount of the emission of carbon dioxide. The results also suggested that a legislation that forces the enterprises to bear the social costs of carbon dioxide emissions resulting from their economic activities is an effective approach to reducing carbon dioxide emissions. PMID:24412595

Tseng, Shih-Chang; Hung, Shiu-Wan

2014-01-15

148

Carbon dioxide emissions from Indian monsoonal estuaries  

NASA Astrophysics Data System (ADS)

Estuaries are known to be strong source for atmospheric CO2, however, little information is available from Indian estuaries. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge (wet) period. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between 300 and 18492 ?atm which are within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

Sarma, V. V. S. S.; Viswanadham, R.; Rao, G. D.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Kumar, N. A.; Rao, D. B.; Sridevi, T.; Krishna, M. S.; Reddy, N. P. C.; Sadhuram, Y.; Murty, T. V. R.

2012-02-01

149

Energy use and carbon emissions: Non-OECD countries  

SciTech Connect

This report surveys world energy use and carbon emissions patterns, with particular emphasis on the non-OECD countries. The non OECD is important not only because it currently makes up 84% of world population, but because its energy consumption, carbon emissions, population, and grow domestic product have all been growing faster than OECD`s. This presentation has seven major sections: (1) overview of key trends in non-OECD energy use and carbon emissions since 1970; (2) Comparison and contrasting energy use and carbon emissions for five major non OEDC regions (former Soviet Union and eastern Europe, Pacific Rim including China, Latin America, other Asia; Africa; 3-7) presentation of aggregate and sectoral energy use and carbon emissions data for countries within each of the 5 regions.

Not Available

1994-12-01

150

Reducing Greenhouse Gas Emissions from Agricultural Wetlands in Borneo  

NASA Astrophysics Data System (ADS)

At the forum G20 meeting in 2009, Indonesian President delivered Indonesia's commitment to reduce national greenhouse gas (GHG) emissions by 26% in 2020 by unilateral action and by 41% with support of other countries. To achieve the target, Indonesian government has put forestry, agriculture (including peatlands), energy, industry and transportation as main responsible sectors. Development of crop with low GHG emissions, increasing C sequestration and the use of organic fertilizers are among the activities to be carried out in 2010-2020 period to minimize GHG emissions from agricultural sectors. Three experiments have been carried out to elucidate the reflectivity of crop selection, soil ameliorants and organic fertilizers on GHG emissions from agricultural wetlands in Borneo. Firstly, gas samples were collected in weekly basis from oil palm, paddy, and vegetables fields and analyzed for methane (CH4) and nitrous oxide (N2O) concentrations by a gas chromatography. Secondly, coal fly ash, dolomite and ZnSO4 were incorporated into a pot containing peat and/or alluvial soils taken from wetlands in South Kalimantan. The air samples were taken and analyzed for CH4 by a gas chromatography. Finally, microbial consortium are isolated from soil, sediment and cow dung. The microbes were then propagated and used in a rice straw composting processes. The CO2, CH4 and N2O emissions from composting vessel were measured at one, two and four weeks of composting processes. The results showed that shifting the use of peatlands for oil palm to vegetable field reduced the GHG emissions by about 74% and that to paddy field reduce the GHG emissions by about 82%. The CH4 emissions from paddy field can be further reduced by applying dolomite. However, the use of coal fly ash and ZnSO4 increased CH4 emissions from peat soil cultivated to rice. The use of microbe isolated from saline soil could reduce GHG emissions during the composting of rice straw. The social aspect of GHG reduction in Borneo will also be discussed.

Abdul, H.; Fatah, L.; Nursyamsi, D.; Kazuyuki, I.

2011-12-01

151

Carbon emissions reduction strategies in Africa from improved waste management: A review  

SciTech Connect

The paper summarises a literature review into waste management practices across Africa as part of a study to assess methods to reduce carbon emissions. Research shows that the average organic content for urban Municipal Solid Waste in Africa is around 56% and its degradation is a major contributor to greenhouse gas emissions. The paper concludes that the most practical and economic way to manage waste in the majority of urban communities in Africa and therefore reduce carbon emissions is to separate waste at collection points to remove dry recyclables by door to door collection, compost the remaining biogenic carbon waste in windrows, using the maturated compost as a substitute fertilizer and dispose the remaining fossil carbon waste in controlled landfills.

Couth, R. [University of KwaZulu-Natal, CRECHE, School of Civil Engineering, Survey and Construction, Durban 4041 (South Africa); Trois, C., E-mail: troisc@ukzn.ac.z [University of KwaZulu-Natal, CRECHE, School of Civil Engineering, Survey and Construction, Durban 4041 (South Africa)

2010-11-15

152

Effects of Reduced Greenhouse Gas Emissions on Air Quality  

NASA Astrophysics Data System (ADS)

Climate change and population growth will make it more challenging for California to attain health-based ambient air quality standards for ozone. This so-called climate change penalty will require even more stringent emission control measures on stationary and mobile sources of air pollution to offset the harmful effects of climate change on ozone air quality. California has set a target to decrease greenhouse gas emissions to 1990 levels by the year 2020, and to 80 percent below 1990 levels by 2050. We analyze the potential effects on air quality due to the first (2020) target for greenhouse gas emissions in central California. The anticipated control measures will also affect ozone precursor emissions. We develop a set of air pollution emission scenarios for central California as of 2020, and predict resulting ozone concentrations for each case. We take into account the Draft AB 32 Scoping Document and regional/state level air quality control plans, as well as the effects of population growth and technology change. This allows us to elucidate and quantify the interactions between California's air pollution and greenhouse gas control programs. An important opportunity for synergy between control programs is to place more emphasis on greenhouse gas reductions in the diesel sector, as these engines are now the dominant source of NOx and black carbon emissions in California, as well as contributing significantly to CO2.

Shearer, S. M.; Harley, R.

2008-12-01

153

Emission Characteristics of NOx and Unburned Carbon in Fly Ash of Sub-bituminous Coal Combustion  

NASA Astrophysics Data System (ADS)

Sub-bituminous coal is considered to be one substitute fuel for bituminous coal. Since sub-bituminous coal contains more than 20% moisture, there are some problems with its utilization, such as a decrease in combustibility, high NOx emission and so on. This report describes the emission characteristics of NOx and unburned carbon in fly ash of sub-bituminous coal combustion through the use of a pulverized coal combustion test furnace. On the sub-bituminous coal combustion, ignition at the burner exit worsened and the combustion flame became diffused. Then, both NOx emission and the unburned carbon concentration in fly ash became high. In order to keep stable combustion and to form an effective NOx reduction flame, the swirl vane angle of secondary air was reduced and the Air/Coal ratio was lowered. As a result, the combustion flame became moderate, and both NOx emission and unburned carbon concentration in fly ash could be reduced.

Ikeda, Michitaka; Kozai, Yukitoshi; Makino, Hisao

154

Unsuccessful suicide by carbon monoxide: a secondary benefit of emissions control  

SciTech Connect

Emission systems and devices are required on automobile engines to reduce air pollution problems. Catalytic converters have been used on most 1975 and newer automobiles to reduce hydrocarbon and carbon monoxide (CO) emissions to a value that meets the Environmental Protection Agency requirements established for 1975 and 1976. The 1980-1981 Boise, Idaho, study shows that with a functioning catalytic converter either unmeasurable or sublethal quantities of CO appear in automobile exhaust. Thus, emissions control has produced a secondary benefit in reducing the number of suicides by CO poisoning from automobile exhaust fumes.

Landers, D.

1981-11-01

155

Research developments in methods to reduce the carbon footprint of the food system: a review.  

PubMed

Abstract Global warming is a worldwide issue with its evident impact across a wide range of systems and sectors. It is caused by a number of greenhouse gases (GHGs) emissions, in which food system has made up of a large part. Recently, reduction of GHG emissions has become an urgent issue to be resolved in the food system. Many governments and organizations are making great endeavors to alleviate the adverse effect of this phenomenon. In this review, methods to reduce the carbon footprint within the life cycle of a food system are presented from the technical, consumption behavior, and environmental policies perspectives. The whole food system including raw material acquisition, processing, packaging, preservation, transportation, consumption and disposal are covered. Improving management techniques, and adopting advanced technology and equipment are critical for every stages of a food system. Rational site selection is important to alleviate the influence of land use change. In addition, environmental choices of packaging stage, reduction in refrigeration dependence, and correct waste treatment are essential to reduce the total carbon footprint of the production. However, only technical methods cannot radically reverse the trend of climate change, as consumption behaviors present a great deal of influence over climate change. Appropriate purchase patterns and substitution within food product categories by low carbon products can reduce GHG emissions. Development of methods to calculate the carbon footprint of every kind of food and its processing technology enable people to make environmental choice. Policy can shape and cultivate the new code of consumption and influence the direction of emerging technology and science. From political perspectives, government intervention and carbon offset are common tools, especially for carbon tax and a real or implicit price of carbon. Finally, by mitigating the methodologies described above, the rate and magnitude of climate changes can be also reduced to some extent. PMID:24689789

Xu, Zhongyue; Sun, Da-Wen; Zeng, Xin-An; Liu, Dan; Pu, Hongbin

2014-04-01

156

Reducing transit bus emissions: Alternative fuels or traffic operations?  

NASA Astrophysics Data System (ADS)

In this study, we simulated the operations and greenhouse gas (GHG) emissions of transit buses along a busy corridor and quantified the effects of two different fuels (conventional diesel and compressed natural gas) as well as a set of driving conditions on emissions. Results indicate that compressed natural gas (CNG) reduces GHG emissions by 8-12% compared to conventional diesel, this reduction could increase to 16% with high levels of traffic congestion. However, the benefits of switching from conventional diesel to CNG are less apparent when the road network is uncongested. We also investigated the effects of bus operations on emissions by applying several strategies such as transit signal priority (TSP), queue jumper lanes, and relocation of bus stops. Results show that in congested conditions, TSP alone can reduce GHG emissions by 14% and when combined with improved technology; a reduction of 23% is achieved. The reduction benefits are even more apparent when other transit operational improvements are combined with TSP. Finally a sensitivity analysis was performed to investigate the effect of operational improvements on emissions under varying levels of network congestion. We observe that under extreme congestion, the benefits of TSP decrease.

Alam, Ahsan; Hatzopoulou, Marianne

2014-06-01

157

The role of carbon dioxide in ammonia emission from manure  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ammonia emission from manure is a significant loss of fixed N from agricultural systems, and contributes to air pollution and ecosystem degradation. Despite the development of numerous mathematical models for predicting ammonia emission, the interactions between carbon dioxide emission, manure pH, a...

158

Wellbeing Impacts of City Policies for Reducing Greenhouse Gas Emissions  

PubMed Central

To mitigate climate change, city authorities are developing policies in areas such as transportation, housing and energy use, to reduce greenhouse gas emissions. In addition to their effects on greenhouse gas emissions, these policies are likely to have consequences for the wellbeing of their populations for example through changes in opportunities to take physical exercise. In order to explore the potential consequences for wellbeing, we first explore what wellbeing is and how it can be operationalized for urban planners. In this paper, we illustrate how wellbeing can be divided into objective and subjective aspects which can be measured quantitatively; our review of measures informs the development of a theoretical model linking wellbeing to policies which cities use to reduce greenhouse gas emissions. Finally, we discuss the extent to which the links proposed in the conceptual model are supported by the literature and how cities can assess wellbeing implications of policies. PMID:25464129

Hiscock, Rosemary; Mudu, Pierpaolo; Braubach, Matthias; Martuzzi, Marco; Perez, Laura; Sabel, Clive

2014-01-01

159

Wellbeing impacts of city policies for reducing greenhouse gas emissions.  

PubMed

To mitigate climate change, city authorities are developing policies in areas such as transportation, housing and energy use, to reduce greenhouse gas emissions. In addition to their effects on greenhouse gas emissions, these policies are likely to have consequences for the wellbeing of their populations for example through changes in opportunities to take physical exercise. In order to explore the potential consequences for wellbeing, we first explore what 'wellbeing' is and how it can be operationalised for urban planners. In this paper, we illustrate how wellbeing can be divided into objective and subjective aspects which can be measured quantitatively; our review of measures informs the development of a theoretical model linking wellbeing to policies which cities use to reduce greenhouse gas emissions. Finally, we discuss the extent to which the links proposed in the conceptual model are supported by the literature and how cities can assess wellbeing implications of policies. PMID:25464129

Hiscock, Rosemary; Mudu, Pierpaolo; Braubach, Matthias; Martuzzi, Marco; Perez, Laura; Sabel, Clive

2014-12-01

160

TRANSIENT SUPPRESSION PACKAGING FOR REDUCED EMISSIONS FROM ROTARY KILN INCINERATORS  

EPA Science Inventory

Experiments were performed on a 73 kW rotary kiln incinerator simulator to determine whether innovative waste packaging designs might reduce transient emissions of products of incomplete combustion due to batch charging of containerized liquid surrogate waste compounds bound on g...

161

Attempts to Reduce NOx Exhaust Emissions by Using Reformulated Biodiesel  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two routes were investigated for reformulating soy-based biodiesel in an effort to reduce its nitrogen oxide emissions. In the first approach, methyl soyate was modified by converting a proportion of the cis-bonds in the fatty acid chains of its methyl esters to their trans isomers. In the second ...

162

A reduced organic carbon component in martian basalts.  

PubMed

The source and nature of carbon on Mars have been a subject of intense speculation. We report the results of confocal Raman imaging spectroscopy on 11 martian meteorites, spanning about 4.2 billion years of martian history. Ten of the meteorites contain abiotic macromolecular carbon (MMC) phases detected in association with small oxide grains included within high-temperature minerals. Polycyclic aromatic hydrocarbons were detected along with MMC phases in Dar al Gani 476. The association of organic carbon within magmatic minerals indicates that martian magmas favored precipitation of reduced carbon species during crystallization. The ubiquitous distribution of abiotic organic carbon in martian igneous rocks is important for understanding the martian carbon cycle and has implications for future missions to detect possible past martian life. PMID:22628557

Steele, A; McCubbin, F M; Fries, M; Kater, L; Boctor, N Z; Fogel, M L; Conrad, P G; Glamoclija, M; Spencer, M; Morrow, A L; Hammond, M R; Zare, R N; Vicenzi, E P; Siljestrm, S; Bowden, R; Herd, C D K; Mysen, B O; Shirey, S B; Amundsen, H E F; Treiman, A H; Bullock, E S; Jull, A J T

2012-07-13

163

Electron field emission from reduced graphene oxide on polymer film  

NASA Astrophysics Data System (ADS)

Field emission of reduced graphene oxide coated on polystyrene film is studied in both parallel and perpendicular configurations. Low turn-on field of 0.6 V/?m and high emission current density of 200 mA/cm2 are observed in perpendicular configuration (along the cross section), whereas a turn-on field of 6 V/?m and current density of 20 ?A/cm2 are obtained in parallel configuration (top surface). The emission characteristics follow Fowler-Nordheim (FN) tunneling and the values of enhancement factor estimated from FN plots are 5818 (perpendicular) and 741 (parallel). Furthermore, stability and repeatability of the field emission characteristics in perpendicular configuration are presented.

Sameera, I.; Bhatia, Ravi; Ouyang, Jianyong; Prasad, V.; Menon, R.

2013-01-01

164

Simple menaquinones reduce carbon tetrachloride and iron (III)  

Microsoft Academic Search

Cell-free supernatant from Shewanella oneidensis MR-1 reduced carbon tetrachloride to chloroform, a suspension of Fe(III) and solid Fe(III) to iron (II). The putative reducing\\u000a agent was tentatively identified as menaquinone-1 (MQ-1)a water-soluble menaquinone with a single isoprenoid residue in the\\u000a side chain. Synthetic MQ-1 reduced carbon tetrachloride to chloroform and amorphous iron (III) hydroxide to iron (II). To\\u000a test the

Q. Shiang Fu; Benjaporn Boonchayaanant; Weiping Tang; Barry M. Trost; Craig S. Criddle

2009-01-01

165

Effects of reducing SO2 and NOx emission from ships on air quality in Alaska  

NASA Astrophysics Data System (ADS)

We performed simulations with the Alaska-adapted WRF/Chem using the same meteorological conditions of January 2000, but alternatively applying the emissions of 2000 (REF), emissions of 2000 with the ship-emission reductions for the planned North American Emission Contral Area (ECA) for SO2 only (ECA1) and SO2 and NOx (ECA2) that have been proposed by the International Maritime Organization for 2015. The analysis focused on the air quality along the international shipping lanes (ISL), in the ECA and over Alaska (AK). Our goal is to examine how the decreases in ship emissions in the ISL and ECA affect to air quality in Alaska. Our model results show that reducing SO2 and NOx ship-emissions reduces the concentration of sulfur and nitrogen compounds over Alaska despite of no changes in Alaska emissions. The reductions of pollutants over the ISL, ECA and AK stemming from concurrent SO2-NOx ship emission reductions are an order of magnitude of those stemming from SO2 reduction in ship emissions only. Reductions in sulfur compounds reach up to 14km while reductions of nitrogen compounds reach to only about 7km. Reductions of sulfate and nitrate in clouds are highest at the top of the boundary layer. Among the three regions of interest, strongest reductions occur over the ECA and ISL for sulfur and nitrogen compounds, respectively, since the ECA (ISL) has highest reductions of SO2 (NOx). The PM2.5 speciation partitioning over all three regions marginally changes when the ship emissions change. Sulfate is the major component of PM2.5 in all regions. Closer to the land, organic carbon (OC) partitioning is higher indicating the enhancing impacts of inland anthropogenic emissions to total PM2.5 concentrations over land.

Tran, T. T.; Mlders, N.

2011-12-01

166

New technologies reduce greenhouse gas emissions from nitrogenous fertilizer in China.  

PubMed

Synthetic nitrogen (N) fertilizer has played a key role in enhancing food production and keeping half of the world's population adequately fed. However, decades of N fertilizer overuse in many parts of the world have contributed to soil, water, and air pollution; reducing excessive N losses and emissions is a central environmental challenge in the 21st century. China's participation is essential to global efforts in reducing N-related greenhouse gas (GHG) emissions because China is the largest producer and consumer of fertilizer N. To evaluate the impact of China's use of N fertilizer, we quantify the carbon footprint of China's N fertilizer production and consumption chain using life cycle analysis. For every ton of N fertilizer manufactured and used, 13.5 tons of CO2-equivalent (eq) (t CO2-eq) is emitted, compared with 9.7 t CO2-eq in Europe. Emissions in China tripled from 1980 [131 terrogram (Tg) of CO2-eq (Tg CO2-eq)] to 2010 (452 Tg CO2-eq). N fertilizer-related emissions constitute about 7% of GHG emissions from the entire Chinese economy and exceed soil carbon gain resulting from N fertilizer use by several-fold. We identified potential emission reductions by comparing prevailing technologies and management practices in China with more advanced options worldwide. Mitigation opportunities include improving methane recovery during coal mining, enhancing energy efficiency in fertilizer manufacture, and minimizing N overuse in field-level crop production. We find that use of advanced technologies could cut N fertilizer-related emissions by 20-63%, amounting to 102-357 Tg CO2-eq annually. Such reduction would decrease China's total GHG emissions by 2-6%, which is significant on a global scale. PMID:23671096

Zhang, Wei-Feng; Dou, Zheng-Xia; He, Pan; Ju, Xiao-Tang; Powlson, David; Chadwick, Dave; Norse, David; Lu, Yue-Lai; Zhang, Ying; Wu, Liang; Chen, Xin-Ping; Cassman, Kenneth G; Zhang, Fu-Suo

2013-05-21

167

Market-driven emissions from recovery of carbon dioxide gas.  

PubMed

This article uses a market-based allocation method in a consequential life cycle assessment (LCA) framework to estimate the environmental emissions created by recovering carbon dioxide (CO2). We find that 1 ton of CO2 recovered as a coproduct of chemicals manufacturing leads to additional greenhouse gas emissions of 147-210 kg CO2 eq , while consuming 160-248 kWh of electricity, 254-480 MJ of heat, and 1836-4027 kg of water. The ranges depend on the initial and final purity of the CO2, particularly because higher purity grades require additional processing steps such as distillation, as well as higher temperature and flow rate of regeneration as needed for activated carbon treatment and desiccant beds. Higher purity also reduces process efficiency due to increased yield losses from regeneration gas and distillation reflux. Mass- and revenue-based allocation methods used in attributional LCA estimate that recovering CO2 leads to 19 and 11 times the global warming impact estimated from a market-based allocation used in consequential LCA. PMID:25412142

Supekar, Sarang D; Skerlos, Steven J

2014-12-16

168

China's Energy and Carbon Emissions Outlook to 2050  

SciTech Connect

As a result of soaring energy demand from a staggering pace of economic expansion and the related growth of energy-intensive industry, China overtook the United States to become the world's largest contributor to CO{sub 2} emissions in 2007. At the same time, China has taken serious actions to reduce its energy and carbon intensity by setting both a short-term energy intensity reduction goal for 2006 to 2010 as well as a long-term carbon intensity reduction goal for 2020. This study presents a China Energy Outlook through 2050 that assesses the role of energy efficiency policies in transitioning China to a lower emission trajectory and meeting its intensity reduction goals. Over the past few years, LBNL has established and significantly enhanced its China End-Use Energy Model which is based on the diffusion of end-use technologies and other physical drivers of energy demand. This model presents an important new approach for helping understand China's complex and dynamic drivers of energy consumption and implications of energy efficiency policies through scenario analysis. A baseline ('Continued Improvement Scenario') and an alternative energy efficiency scenario ('Accelerated Improvement Scenario') have been developed to assess the impact of actions already taken by the Chinese government as well as planned and potential actions, and to evaluate the potential for China to control energy demand growth and mitigate emissions. In addition, this analysis also evaluated China's long-term domestic energy supply in order to gauge the potential challenge China may face in meeting long-term demand for energy. It is a common belief that China's CO{sub 2} emissions will continue to grow throughout this century and will dominate global emissions. The findings from this research suggest that this will not necessarily be the case because saturation in ownership of appliances, construction of residential and commercial floor area, roadways, railways, fertilizer use, and urbanization will peak around 2030 with slowing population growth. The baseline and alternative scenarios also demonstrate that China's 2020 goals can be met and underscore the significant role that policy-driven energy efficiency improvements will play in carbon mitigation along with a decarbonized power supply through greater renewable and non-fossil fuel generation.

Zhou, Nan; Fridley, David; McNeil, Michael; Zheng, Nina; Ke, Jing; Levine, Mark

2011-02-15

169

Cumulative emission budgets and their implications: the case for SAFE carbon  

NASA Astrophysics Data System (ADS)

The risk of dangerous long-term climate change due to anthropogenic carbon dioxide emissions is predominantly determined by cumulative emissions over all time, not the rate of emission in any given year or commitment period. This has profound implications for climate mitigation policy: emission targets for specific years such as 2020 or 2050 provide no guarantee of meeting any overall cumulative emission budget. By focusing attention on short-term measures to reduce the flow of emissions, they may even exacerbate the overall long-term stock. Here we consider how climate policies might be designed explicitly to limit cumulative emissions to, for example, one trillion tonnes of carbon, a figure that has been estimated to give a most likely warming of two degrees above pre-industrial, with a likely range of 1.6-2.6 degrees. Three approaches are considered: tradable emission permits with the possibility of indefinite emission banking, carbon taxes explicitly linked to cumulative emissions and mandatory carbon sequestration. Framing mitigation policy around cumulative targets alleviates the apparent tension between climate protection and short-term consumption that bedevils any attempt to forge global agreement. We argue that the simplest and hence potentially the most effective approach might be a mandatory requirement on the fossil fuel industry to ensure that a steadily increasing fraction of fossil carbon extracted from the ground is artificially removed from the active carbon cycle through some form of sequestration. We define Sequestered Adequate Fraction of Extracted (SAFE) carbon as a source in which this sequestered fraction is anchored to cumulative emissions, increasing smoothly to reach 100% before we release the trillionth tonne. While adopting the use of SAFE carbon would increase the cost of fossil energy much as a system of emission permits or carbon taxes would, it could do so with much less explicit government intervention. We contrast this proposal with, for example, the WBGU budget approach which also recognises the importance of cumulative emissions, noting their different implications for global equity and development considerations. The implications of cumulative emissions for the issue of historical responsibility for adaptation costs will also be discussed.

Allen, Myles; Bowerman, Niel; Frame, David; Mason, Charles

2010-05-01

170

[Research on contribution decomposition by industry to China's carbon intensity reduction and carbon emission growth].  

PubMed

The binding carbon intensity index and the pilot "cap-and-trade" emission trading scheme are two important approaches currently applied by China to mitigate its greenhouse gases emissions. It is of great significance to research the influence mechanism of related factors by industry on the dynamics of national carbon intensity and emission, not only for setting industry-specified intensity reduction target but also for setting industry coverage of the ETS. Two LMDI models were applied in this paper to decompose industry contributions to the changes of China's carbon intensity and carbon emission during the period of 1996-2010. Empirical results showed that: The decline of national carbon intensity was jointly determined by the changes of carbon intensities and the added value proportions of all industries, and the impact of industry carbon intensities was larger. The increase of national carbon emission was jointly determined by the changes of carbon intensities and the added value of all industries. The former had inhibitory effect whist the latter had decisive promoting effect. The five industries making the largest contribution to the changes of national carbon emission and carbon intensity included industries of electricity, nonmetal mineral, ferrous metal, transportation service, chemical materials, which were followed by the industries of agriculture, coal mining and processing, petroleum and natural gas extraction. Petroleum refining and coking industry and construction industry made small contribution to the decline of national carbon intensity, but made large contribution to the growth of national carbon emission. The contributions of service industries to national carbon emission growth showed a rising trend, especially those of transportation service industry, wholesaling, retailing and catering service industry. PMID:25639120

Jiang, Jing-Jing; Ye, Bin; Ji, Jun-Ping; Ma, Xiao-Ming

2014-11-01

171

Short and Long Term Impacts of Forest Bioenergy Production on Atmospheric Carbon Dioxide Emissions  

NASA Astrophysics Data System (ADS)

Temperate forest annual net uptake of CO2 from the atmosphere is equivalent to ~16% of the annual fossil fuel emissions in the United States. Mitigation strategies to reduce emissions of carbon dioxide have lead to investigation of alternative sources of energy including forest biomass. The prospect of forest derived bioenergy has led to implementation of new forest management strategies based on the assumption that they will reduce total CO2 emissions to the atmosphere by simultaneously reducing the risk of wildfire and substituting for fossil fuels. The benefit of managing forests for bioenergy substitution of fossil fuels versus potential carbon sequestration by reducing harvest needs to be evaluated. This study uses a combination of Federal Forest Inventory data (FIA), remote sensing, and a coupled carbon-nitrogen ecosystem process model (CLM4-CN) to predict net atmospheric CO2 emissions from forest thinning for bioenergy production in Oregon under varying future management and climate scenarios. We use life-cycle assessment (LCA) incorporating both the forest and forest product sinks and sources of carbon dioxide. Future modeled results are compared with a reduced harvest scenario to determine the potential for increased carbon sequestration in forest biomass. We find that Oregon forests are a current strong sink of 7.5 1.7 Tg C yr-1 or 61 g C m-2 yr-1. (NBP; NEP minus removals from fire and harvest). In the short term, we find that carbon dynamics following harvests for fire prevention and large-scale bioenergy production lead to 2-15% higher emissions over the next 20 years compared to current management, assuming 100% effectiveness of fire prevention. Given the current sink strength, analysis of the forest sector in Oregon demonstrates that increasing harvest levels by all practices above current business-as-usual levels increases CO2 emissions to the atmosphere as long as the region's sink persists. In the long-term, we find that projected changes in climate and fire regimes reduce the baseline sink in drier portions of the state making thinning for bioenergy production an effective means to reduce atmospheric emissions. However, in the more productive wetter areas, management for carbon sequestration removes more CO2 from the atmosphere than substitution of fossil fuels with forest bioenergy. Management strategies should consider the emission reduction potential of reducing harvest in some areas before implementing bioenergy production.

Hudiburg, T.; Law, B. E.; Luyssaert, S.; Thornton, P. E.

2011-12-01

172

Estimated Carbon Dioxide Emissions in 2008: United States  

SciTech Connect

Flow charts depicting carbon dioxide emissions in the United States have been constructed from publicly available data and estimates of state-level energy use patterns. Approximately 5,800 million metric tons of carbon dioxide were emitted throughout the United States for use in power production, residential, commercial, industrial, and transportation applications in 2008. Carbon dioxide is emitted from the use of three major energy resources: natural gas, coal, and petroleum. The flow patterns are represented in a compact 'visual atlas' of 52 state-level (all 50 states, the District of Columbia, and one national) carbon dioxide flow charts representing a comprehensive systems view of national CO{sub 2} emissions. Lawrence Livermore National Lab (LLNL) has published flow charts (also referred to as 'Sankey Diagrams') of important national commodities since the early 1970s. The most widely recognized of these charts is the U.S. energy flow chart (http://flowcharts.llnl.gov). LLNL has also published charts depicting carbon (or carbon dioxide potential) flow and water flow at the national level as well as energy, carbon, and water flows at the international, state, municipal, and organizational (i.e. United States Air Force) level. Flow charts are valuable as single-page references that contain quantitative data about resource, commodity, and byproduct flows in a graphical form that also convey structural information about the system that manages those flows. Data on carbon dioxide emissions from the energy sector are reported on a national level. Because carbon dioxide emissions are not reported for individual states, the carbon dioxide emissions are estimated using published energy use information. Data on energy use is compiled by the U.S. Department of Energy's Energy Information Administration (U.S. EIA) in the State Energy Data System (SEDS). SEDS is updated annually and reports data from 2 years prior to the year of the update. SEDS contains data on primary resource consumption, electricity generation, and energy consumption within each economic sector. Flow charts of state-level energy usage and explanations of the calculations and assumptions utilized can be found at: http://flowcharts.llnl.gov. This information is translated into carbon dioxide emissions using ratios of carbon dioxide emissions to energy use calculated from national carbon dioxide emissions and national energy use quantities for each particular sector. These statistics are reported annually in the U.S. EIA's Annual Energy Review. Data for 2008 (US. EIA, 2010) was updated in August of 2010. This is the first presentation of a comprehensive state-level package of flow charts depicting carbon dioxide emissions for the United States.

Smith, C A; Simon, A J; Belles, R D

2011-04-01

173

The proportionality of global warming to cumulative carbon emissions.  

PubMed

The global temperature response to increasing atmospheric CO(2) is often quantified by metrics such as equilibrium climate sensitivity and transient climate response. These approaches, however, do not account for carbon cycle feedbacks and therefore do not fully represent the net response of the Earth system to anthropogenic CO(2) emissions. Climate-carbon modelling experiments have shown that: (1) the warming per unit CO(2) emitted does not depend on the background CO(2) concentration; (2) the total allowable emissions for climate stabilization do not depend on the timing of those emissions; and (3) the temperature response to a pulse of CO(2) is approximately constant on timescales of decades to centuries. Here we generalize these results and show that the carbon-climate response (CCR), defined as the ratio of temperature change to cumulative carbon emissions, is approximately independent of both the atmospheric CO(2) concentration and its rate of change on these timescales. From observational constraints, we estimate CCR to be in the range 1.0-2.1 degrees C per trillion tonnes of carbon (Tt C) emitted (5th to 95th percentiles), consistent with twenty-first-century CCR values simulated by climate-carbon models. Uncertainty in land-use CO(2) emissions and aerosol forcing, however, means that higher observationally constrained values cannot be excluded. The CCR, when evaluated from climate-carbon models under idealized conditions, represents a simple yet robust metric for comparing models, which aggregates both climate feedbacks and carbon cycle feedbacks. CCR is also likely to be a useful concept for climate change mitigation and policy; by combining the uncertainties associated with climate sensitivity, carbon sinks and climate-carbon feedbacks into a single quantity, the CCR allows CO(2)-induced global mean temperature change to be inferred directly from cumulative carbon emissions. PMID:19516338

Matthews, H Damon; Gillett, Nathan P; Stott, Peter A; Zickfeld, Kirsten

2009-06-11

174

Effect of Purity and Substrate on Field Emission Properties of Multi-walled Carbon Nanotubes.  

PubMed

Multi-walled carbon nanotubes (MWNT) have been synthesized by chemical vapour decomposition (CVD) of acetylene over Rare Earth (RE) based AB2(DyNi2) alloy hydride catalyst. The as-grown carbon nanotubes were purified by acid and heat treatments and characterized using powder X-ray diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, Thermo Gravimetric Analysis and Raman Spectroscopy. Fully carbon based field emitters have been fabricated by spin coating a solutions of both as-grown and purified MWNT and dichloro ethane (DCE) over carbon paper with and without graphitized layer. The use of graphitized carbon paper as substrate opens several new possibilities for carbon nanotube (CNT) field emitters, as the presence of the graphitic layer provides strong adhesion between the nanotubes and carbon paper and reduces contact resistance. The field emission characteristics have been studied using an indigenously fabricated set up and the results are discussed. CNT field emitter prepared by spin coating of the purified MWNT-DCE solution over graphitized carbon paper shows excellent emission properties with a fairly stable emission current over a period of 4 h. Analysis of the field emission characteristics based on the Fowler-Nordheim (FN) theory reveals current saturation effects at high applied fields for all the samples. PMID:21798103

Rakhi, Rb; Sethupathi, K; Ramaprabhu, S

2007-01-01

175

Effect of Purity and Substrate on Field Emission Properties of Multi-walled Carbon Nanotubes  

PubMed Central

Multi-walled carbon nanotubes (MWNT) have been synthesized by chemical vapour decomposition (CVD) of acetylene over Rare Earth (RE) based AB2(DyNi2) alloy hydride catalyst. The as-grown carbon nanotubes were purified by acid and heat treatments and characterized using powder X-ray diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, Thermo Gravimetric Analysis and Raman Spectroscopy. Fully carbon based field emitters have been fabricated by spin coating a solutions of both as-grown and purified MWNT and dichloro ethane (DCE) over carbon paper with and without graphitized layer. The use of graphitized carbon paper as substrate opens several new possibilities for carbon nanotube (CNT) field emitters, as the presence of the graphitic layer provides strong adhesion between the nanotubes and carbon paper and reduces contact resistance. The field emission characteristics have been studied using an indigenously fabricated set up and the results are discussed. CNT field emitter prepared by spin coating of the purified MWNTDCE solution over graphitized carbon paper shows excellent emission properties with a fairly stable emission current over a period of 4 h. Analysis of the field emission characteristics based on the FowlerNordheim (FN) theory reveals current saturation effects at high applied fields for all the samples. PMID:21798103

2007-01-01

176

Reducing GHG emissions by co-utilization of coal with natural gas or biomass  

SciTech Connect

Energy reserves price and security of supply issues are discussed in the context of the prospects for coal and policies to reduce greenhouse gas (GHG) emissions. Coal is projected to remain a major source of energy, with most of the demand growth in developing countries. Currently available power-generating technologies, deploying coal with natural gas or biomass, are examined. Examples of successful, partial substitution of coal by other fuels in power stations are highlighted, including the GHG emissions reductions achieved as well as the costs where available. Among various options, hybrid gasification and parallel cofiring of coal with biomass and natural gas appear to have the greatest potential to reduce GHG emissions. Much may also be achieved by cofiring, reburning, and repowering with gas turbines. The best method differs between different power systems. Co-utilization of biomass with coal is a least-cost option to reduce GHG emissions where the fuel prices are comparable, usually due to subsidies or taxes. The role of biomass is likely to increase due to greater use of subsidies, carbon taxes, and emissions trading within the context of the Kyoto Protocol. This should provide opportunities for clean coal technology transfer and diffusion, including biomass co-utilization. 32 refs., 1 fig., 3 tabs.

Smith, I.M. [IEA Clean Coal Centre, London (United Kingdom)

2004-07-01

177

Modification of carbon-fiber-composite surface emissivity/reflectance by high-index interference films  

NASA Astrophysics Data System (ADS)

High strength/weight carbon fiber-reinforced composites (CFRCs) are finding applications where control of surface infrared emission or reflection is desirable. A quarter wave sputtered Ge film has been shown to reduce the normal emittance of a bismaleimide CFRC in the 8 - 14 micrometers band by 39%, with angle dependence theoretically constant out to 80% off-axis. A three-layer HLH stack is predicted to reduce emittance of less than 0.1. For thermal IR polymer curing, a single-layer coating optimizing emissivity in the polymer's absorption band while suppressing emission at longer wavelengths may yield electric power savings in the 10 - 20% range.

Pike, John N.; Matthews, Linn H.

1997-10-01

178

Rotary Cement Kiln Control for Reducing NOx Emissions to Atmosphere  

Microsoft Academic Search

A logic procedure, including 12 alternatives within 32 activities and 13 decision nodes has been designed\\/developed\\/implemented for the rotary cement kiln control aiming at reducing NOx emissions to atmosphere. The hierarchy of alternatives was evaluated through simple and top-down Kendall's coefficients of concordance, proved to be of statistical significance. An implementation is presented in the case of fuel substitution including

Fragiskos A. Batzias

2006-01-01

179

Carbon emissions and sequestration in forests: Case studies from seven developing countries  

SciTech Connect

Forests are a major source of carbon dioxide emissions in developing countries, in most cases far exceeding the emissions from the energy sector. To date, however, efforts at quantifying forestry emissions have produced a wide range of results. In order to assist policymakers in developing measures to reduce emissions' levels and to increase carbon sequestration, the Tropical Forest Research Network (F-7) has undertaken this effort to improve the precision of emissions estimates and to identify possible response options in the forestry sector. This paper summarizes the results of one component of this work. The Tropical Forest Research Network (F-7) was established in 1990 as part of the Intergovernmental Panel on Climate Change's (IPCC) activities in examining growing emissions of greenhouse gases and their potential impact on the global climate. Unlike past methods, this study relied on a network of participants from developing countries to prepare estimates of carbon emissions. The participating countries -- Brazil, China, India, Indonesia, Malaysia, Mexico and Thailand -- currently represent an estimated two-thirds of the annual deforestation of closed moist forests. This study gives an estimate of 837 million tonnes of carbon emissions from deforestation and logging in the F-7 countries in 1990. A proportional projection of these estimates to the tropical biome shows that the total carbon emissions are between 1.1 and 1.7 billion tonnes of carbon, with a working average of 1.4 billion tonnes per year. This work also provides estimates of emissions and uptake from China, which past studies rarely have included. This summary will be followed by individual reports by each of the participating countries, which will include detailed evaluations of possible response options. Estimates for Nigeria are also under preparation.

Makundi, W.; Sathaye, J. (eds.); Cerutti, O.M.

1992-08-01

180

Derivation of burn scar depths and estimation of carbon emissions with LIDAR in Indonesian peatlands  

PubMed Central

During the 1997/98 El Nio-induced drought peatland fires in Indonesia may have released 1340% of the mean annual global carbon emissions from fossil fuels. One major unknown in current peatland emission estimations is how much peat is combusted by fire. Using a light detection and ranging data set acquired in Central Kalimantan, Borneo, in 2007, one year after the severe peatland fires of 2006, we determined an average burn scar depth of 0.33 0.18 m. Based on this result and the burned area determined from satellite imagery, we estimate that within the 2.79 million hectare study area 49.15 26.81 megatons of carbon were released during the 2006 El Nio episode. This represents 1033% of all carbon emissions from transport for the European Community in the year 2006. These emissions, originating from a comparatively small area (approximately 13% of the Indonesian peatland area), underline the importance of peat fires in the context of green house gas emissions and global warming. In the past decade severe peat fires occurred during El Nio-induced droughts in 1997, 2002, 2004, 2006, and 2009. Currently, this important source of carbon emissions is not included in IPCC carbon accounting or in regional and global carbon emission models. Precise spatial measurements of peat combusted and potential avoided emissions in tropical peat swamp forests will also be required for future emission trading schemes in the framework of Reduced Emissions from Deforestation and Degradation in developing countries. PMID:19940252

Ballhorn, Uwe; Siegert, Florian; Mason, Mike; Limin, Suwido

2009-01-01

181

Carbon emissions and sequestration in forests: Case studies from seven developing countries. Volume 1, Summary: Draft  

SciTech Connect

Forests are a major source of carbon dioxide emissions in developing countries, in most cases far exceeding the emissions from the energy sector. To date, however, efforts at quantifying forestry emissions have produced a wide range of results. In order to assist policymakers in developing measures to reduce emissions` levels and to increase carbon sequestration, the Tropical Forest Research Network (F-7) has undertaken this effort to improve the precision of emissions estimates and to identify possible response options in the forestry sector. This paper summarizes the results of one component of this work. The Tropical Forest Research Network (F-7) was established in 1990 as part of the Intergovernmental Panel on Climate Change`s (IPCC) activities in examining growing emissions of greenhouse gases and their potential impact on the global climate. Unlike past methods, this study relied on a network of participants from developing countries to prepare estimates of carbon emissions. The participating countries -- Brazil, China, India, Indonesia, Malaysia, Mexico and Thailand -- currently represent an estimated two-thirds of the annual deforestation of closed moist forests. This study gives an estimate of 837 million tonnes of carbon emissions from deforestation and logging in the F-7 countries in 1990. A proportional projection of these estimates to the tropical biome shows that the total carbon emissions are between 1.1 and 1.7 billion tonnes of carbon, with a working average of 1.4 billion tonnes per year. This work also provides estimates of emissions and uptake from China, which past studies rarely have included. This summary will be followed by individual reports by each of the participating countries, which will include detailed evaluations of possible response options. Estimates for Nigeria are also under preparation.

Makundi, W.; Sathaye, J. [eds.; Cerutti, O.M.

1992-08-01

182

METHOD FOR MEASURING CARBON FIBER EMISSIONS FROM STATIONARY SOURCES  

EPA Science Inventory

Carbon fibers are highly conductive, lightweight and of small dimensions. When released as emissions from production, manufacturing, processing and disposal sources they may become airborne and disperse over wide areas. If they settle onto electronic or electrical components they...

183

Uncertainty in future carbon emissions : a preliminary exploration  

E-print Network

In order to analyze competing policy approaches for addressing global climate change, a wide variety of economic-energy models are used to project future carbon emissions under various policy scenarios. Due to uncertainties ...

Webster, Mort David.

184

A model of plant isoprene emission based on available reducing power captures responses to atmospheric CO?.  

PubMed

We present a unifying model for isoprene emission by photosynthesizing leaves based on the hypothesis that isoprene biosynthesis depends on a balance between the supply of photosynthetic reducing power and the demands of carbon fixation. We compared the predictions from our model, as well as from two other widely used models, with measurements of isoprene emission from leaves of Populus nigra and hybrid aspen (Populus tremula P. tremuloides) in response to changes in leaf internal CO2 concentration (C(i)) and photosynthetic photon flux density (PPFD) under diverse ambient CO2 concentrations (C(a)). Our model reproduces the observed changes in isoprene emissions with C(i) and PPFD, and also reproduces the tendency for the fraction of fixed carbon allocated to isoprene to increase with increasing PPFD. It also provides a simple mechanism for the previously unexplained decrease in the quantum efficiency of isoprene emission with increasing C(a). Experimental and modelled results support our hypothesis. Our model can reproduce the key features of the observations and has the potential to improve process-based modelling of isoprene emissions by land vegetation at the ecosystem and global scales. PMID:24661143

Morfopoulos, Catherine; Sperlich, Dominik; Peuelas, Josep; Filella, Iolanda; Llusi, Joan; Medlyn, Belinda E; Niinemets, lo; Possell, Malcolm; Sun, Zhihong; Prentice, Iain Colin

2014-07-01

185

Improving farming practices reduces the carbon footprint of spring wheat production  

NASA Astrophysics Data System (ADS)

Wheat is one of the worlds most favoured food sources, reaching millions of people on a daily basis. However, its production has climatic consequences. Fuel, inorganic fertilizers and pesticides used in wheat production emit greenhouse gases that can contribute negatively to climate change. It is unknown whether adopting alternative farming practices will increase crop yield while reducing carbon emissions. Here we quantify the carbon footprint of alternative wheat production systems suited to semiarid environments. We find that integrating improved farming practices (that is, fertilizing crops based on soil tests, reducing summerfallow frequencies and rotating cereals with grain legumes) lowers wheat carbon footprint effectively, averaging ?256?kg CO2 eq?ha?1 per year. For each kg of wheat grain produced, a net 0.0270.377?kg CO2 eq is sequestered into the soil. With the suite of improved farming practices, wheat takes up more CO2 from the atmosphere than is actually emitted during its production.

Gan, Yantai; Liang, Chang; Chai, Qiang; Lemke, Reynald L.; Campbell, Con A.; Zentner, Robert P.

2014-11-01

186

Improving farming practices reduces the carbon footprint of spring wheat production.  

PubMed

Wheat is one of the world's most favoured food sources, reaching millions of people on a daily basis. However, its production has climatic consequences. Fuel, inorganic fertilizers and pesticides used in wheat production emit greenhouse gases that can contribute negatively to climate change. It is unknown whether adopting alternative farming practices will increase crop yield while reducing carbon emissions. Here we quantify the carbon footprint of alternative wheat production systems suited to semiarid environments. We find that integrating improved farming practices (that is, fertilizing crops based on soil tests, reducing summerfallow frequencies and rotating cereals with grain legumes) lowers wheat carbon footprint effectively, averaging -256 kg CO2 eq ha(-1) per year. For each kg of wheat grain produced, a net 0.027-0.377 kg CO2 eq is sequestered into the soil. With the suite of improved farming practices, wheat takes up more CO2 from the atmosphere than is actually emitted during its production. PMID:25405548

Gan, Yantai; Liang, Chang; Chai, Qiang; Lemke, Reynald L; Campbell, Con A; Zentner, Robert P

2014-01-01

187

Multi-layer carbon-based coatings for field emission  

DOEpatents

A multi-layer resistive carbon film field emitter device for cold cathode field emission applications is disclosed. The multi-layered film of the present invention consists of at least two layers of a conductive carbon material, preferably amorphous-tetrahedrally coordinated carbon, where the resistivities of adjacent layers differ. For electron emission from the surface, the preferred structure can be a top layer having a lower resistivity than the bottom layer. For edge emitting structures, the preferred structure of the film can be a plurality of carbon layers, where adjacent layers have different resistivities. Through selection of deposition conditions, including the energy of the depositing carbon species, the presence or absence of certain elements such as H, N, inert gases or boron, carbon layers having desired resistivities can be produced. 8 figs.

Sullivan, J.P.; Friedmann, T.A.

1998-10-13

188

Multi-layer carbon-based coatings for field emission  

DOEpatents

A multi-layer resistive carbon film field emitter device for cold cathode field emission applications. The multi-layered film of the present invention consists of at least two layers of a conductive carbon material, preferably amorphous-tetrahedrally coordinated carbon, where the resistivities of adjacent layers differ. For electron emission from the surface, the preferred structure can be a top layer having a lower resistivity than the bottom layer. For edge emitting structures, the preferred structure of the film can be a plurality of carbon layers, where adjacent layers have different resistivities. Through selection of deposition conditions, including the energy of the depositing carbon species, the presence or absence of certain elements such as H, N, inert gases or boron, carbon layers having desired resistivities can be produced.

Sullivan, John P. (Albuquerque, NM); Friedmann, Thomas A. (Albuquerque, NM)

1998-01-01

189

Carbon dioxide emission during forest fires ignited by lightning  

E-print Network

In this paper we developed the model for the carbon dioxide emission from forest fire. The master equation for the spreading of the carbon dioxide to atmosphere is the hyperbolic diffusion equation. In the paper we study forest fire ignited by lightning. In that case the fores fire has the well defined front which propagates with finite velocity.

Pelc, Magdalena

2009-01-01

190

Optimizing Technology to Reduce Mercury and Acid Gas Emissions from Electric Power Plants  

SciTech Connect

Revised maps and associated data show potential mercury, sulfur, and chlorine emissions for U.S. coal by county of origin. Existing coal mining and coal washing practices result in a 25% reduction of mercury in U.S. coal before it is delivered to the power plant. Selection of low-mercury coal is a good mercury control option for plants having hot-side ESP, cold-side ESP, or hot-side ESP/FGD emission controls. Chlorine content is more important for plants having cold-side ESP/FGD or SDA/FF controls; optimum net mercury capture is indicated where chlorine is between 500 and 1000 ppm. Selection of low-sulfur coal should improve mercury capture where carbon in fly ash is used to reduce mercury emissions.

Jeffrey C. Quick; David E. Tabet; Sharon Wakefield; Roger L. Bon

2005-01-31

191

Solid Fuel - Oxygen Fired Combustion for Production of Nodular Reduced Iron to Reduce CO2 Emissions and Improve Energy Efficiencies  

SciTech Connect

The current trend in the steel industry is an increase in iron and steel produced in electric arc furnaces (EAF) and a gradual decline in conventional steelmaking from taconite pellets in blast furnaces. In order to expand the opportunities for the existing iron ore mines beyond their blast furnace customer base, a new material is needed to satisfy the market demands of the emerging steel industry while utilizing the existing infrastructure and materials handling capabilities. This demand creates opportunity to convert iron ore or other iron bearing materials to Nodular Reduced Iron (NRI) in a recently designed Linear Hearth Furnace (LHF). NRI is a metallized iron product containing 98.5 to 96.0% iron and 2.5 to 4% C. It is essentially a scrap substitute with little impurity that can be utilized in a variety of steelmaking processes, especially the electric arc furnace. The objective of this project was to focus on reducing the greenhouse gas emissions (GHG) through reducing the energy intensity using specialized combustion systems, increasing production and the use of biomass derived carbon sources in this process. This research examined the use of a solid fuel-oxygen fired combustion system and compared the results from this system with both oxygen-fuel and air-fuel combustion systems. The solid pulverized fuels tested included various coals and a bio-coal produced from woody biomass in a specially constructed pilot scale torrefaction reactor at the Coleraine Minerals Research Laboratory (CMRL). In addition to combustion, the application of bio-coal was also tested as a means to produce a reducing atmosphere during key points in the fusion process, and as a reducing agent for ore conversion to metallic iron to capture the advantage of its inherent reduced carbon footprint. The results from this study indicate that the approaches taken can reduce both greenhouse gas emissions and the associated energy intensity with the Linear Hearth Furnace process for converting iron ore to metallic iron nodules. Various types of coals including a bio-coal produced though torrefaction can result in production of NRI at reduced GHG levels. The process results coupled with earlier already reported developments indicate that this process technique should be evaluated at the next level in order to develop parameter information for full scale process design. Implementation of the process to full commercialization will require a full cost production analysis and comparison to other reduction technologies and iron production alternatives. The technical results verify that high quality NRI can be produced under various operating conditions at the pilot level.

Donald R. Fosnacht; Richard F. Kiesel; David W. Hendrickson; David J. Englund; Iwao Iwasaki; Rodney L. Bleifuss; Mathew A. Mlinar

2011-12-22

192

Electronic Structure and Field Emission Properties of Carbon Nanobells  

Microsoft Academic Search

We successfully performed ab-initio density functional calculations for the electronic structure of a carbon nanobell. Carbon nanobells, which can also be viewed as short nanotubes (their lengths are of the same order of their diameters) or carbon quantum dots, have exhibited superior field-emission properties.[1] We present the calculated electronic properties that include the electron energy levels and the local density

G. L. Zhao; D. Bagayoko; E. G. Wang

2002-01-01

193

The impact of financial development on carbon emissions: An empirical analysis in China  

Microsoft Academic Search

Given the complexity between China's financial development and carbon emissions, this paper uses some econometric techniques, including cointegration theory, Granger causality test, variance decomposition, etc., to explore the influence of financial development on carbon emissions. Results indicate that, first, China's financial development acts as an important driver for carbon emissions increase, which should be taken into account when carbon emissions

Yue-Jun Zhang

2011-01-01

194

Final Technical Report HFC Concrete: A Low-???????­???¢???????Energy, Carbon-???????­Dioxide-???????­Negative Solution for reducing Industrial Greenhouse Gas Emissions  

SciTech Connect

Solidia/CCSM received funding for further research and development of its Low Temperature Solidification Process (LTS), which is used to create hydrate-free concrete (HFC). LTS/HFC is a technology/materials platform that offers wide applicability in the built infrastructure. Most importantly, it provides a means of making concrete without Portland cement. Cement and concrete production is a major consumer of energy and source of industrial greenhouse gas (GHG) emissions. The primary goal of this project was to develop and commercialize a novel material, HFC, which by replacing traditional concrete and cement, reduces both energy use and GHG emissions in the built infrastructure. Traditional concrete uses Portland Cement (PC) as a binder. PC production involves calcination of limestone at {approx}1450 C, which releases significant amounts of CO{sub 2} gas to the atmosphere and consumes a large amount of energy due to the high temperature required. In contrast, HFC is a carbonate-based hydrate-free concrete (HFC) that consumes CO{sub 2} gas in its production. HFC is made by reaction of silicate minerals with CO{sub 2} at temperatures below 100 C, more than an order-of-magnitude below the temperature required to make PC. Because of this significant difference in temperature, it is estimated that we will be able to reduce energy use in the cement and concrete industry by up to 30 trillion Btu by 2020. Because of the insulating properties of HFC, we believe we will also be able to significantly reduce energy use in the Building sector, though the extent of this saving is not yet quantified. It is estimated that production of a tonne of PC-based concrete requires about 6.2 million Btu of energy and produces over 1 tonne of CO{sub 2} emissions (Choate, 2003). These can be reduced to 1.9 million Btu and 0.025 tonnes of CO{sub 2} emissions per tonne of HFC (with overall CO{sub 2}-negativity possible by increasing carbonation yield). In this way, by replacing PC-based concrete with HFC in infrastructure we can reduce energy use in concrete production by 70%, and reduce CO{sub 2} emissions by 98%; thus the potential to reduce the impact of building materials on global warming and climate change is highly significant. Low Temperature Solidification (LTS) is a breakthrough technology that enables the densification of inorganic materials via a hydrothermal process. The resulting product exhibits excellent control of chemistry and microstructure, to provide durability and mechanical performance that exceeds that of concrete or natural stone. The technology can be used in a wide range of applications including facade panels, interior tiles, roof tiles, countertops, and pre-cast concrete. Replacing traditional building materials and concrete in these applications will result in significant reduction in both energy consumption and CO{sub 2} emissions.

Dr. Larry McCandlish, Principal Investigator; Dr. Richard Riman, Co-Principal Investigator

2012-05-14

195

A technology-based global inventory of black and organic carbon emissions from combustion  

NASA Astrophysics Data System (ADS)

We present a global tabulation of black carbon (BC) and primary organic carbon (OC) particles emitted from combustion. We include emissions from fossil fuels, biofuels, open biomass burning, and burning of urban waste. Previous "bottom-up" inventories of black and organic carbon have assigned emission factors on the basis of fuel type and economic sector alone. Because emission rates are highly dependent on combustion practice, we consider combinations of fuel, combustion type, and emission controls and their prevalence on a regional basis. Central estimates of global annual emissions are 8.0 Tg for black carbon and 33.9 Tg for organic carbon. These estimates are lower than previously published estimates by 25-35%. The present inventory is based on 1996 fuel-use data, updating previous estimates that have relied on consumption data from 1984. An offset between decreased emission factors and increased energy use since the base year of the previous inventory prevents the difference between this work and previous inventories from being greater. The contributions of fossil fuel, biofuel, and open burning are estimated as 38%, 20%, and 42%, respectively, for BC, and 7%, 19%, and 74%, respectively, for OC. We present a bottom-up estimate of uncertainties in source strength by combining uncertainties in particulate matter emission factors, emission characterization, and fuel use. The total uncertainties are about a factor of 2, with uncertainty ranges of 4.3-22 Tg/yr for BC and 17-77 Tg/yr for OC. Low-technology combustion contributes greatly to both the emissions and the uncertainties. Advances in emission characterization for small residential, industrial, and mobile sources and top-down analysis combining field measurements and transport modeling with iterative inventory development will be required to reduce the uncertainties further.

Bond, Tami C.; Streets, David G.; Yarber, Kristen F.; Nelson, Sibyl M.; Woo, Jung-Hun; Klimont, Zbigniew

2004-07-01

196

Impact of European Emissions Trading System (EU-ETS) on carbon emissions and investment decisions in the power sector  

E-print Network

This masters thesis assesses the impact of a emissions trading on short-term carbon abatement and investment decisions in the power sector. Environmental benefits from carbon abatement due to emissions trading are quantified ...

Feilhauer, Stephan M. (Stephan Marvin)

2009-01-01

197

Can Voluntary Environmental Program Reduce Greenhouse Gas Emissions? An Analysis of the US DOE's Climate Challenge Program  

Microsoft Academic Search

This paper assesses the impact of the Climate Challenge Program (CCP), a voluntary environmental agreement (VEA) negotiated between the Department of Energy and the U.S. utility industry. The aim of the agreement was to reduce carbon emissions between 1994 and 2000. Our analysis involved a statistical study based on a panel data set composed of investor- owned power plants (n=358)

Kyoungsun HEO; Kerry KRUTILLA; David H. GOOD

2009-01-01

198

Reducing cold-start emissions by catalytic converter thermal management  

SciTech Connect

Vacuum insulation and phase-change thermal storage have been used to enhance the heat retention of a prototype catalytic converter. Storing heat in the converter between trips allows exhaust gases to be converted more quickly, significantly reducing cold-start emissions. Using a small metal hydride, the thermal conductance of the vacuum insulation can be varied continuously between 0.49 and 27 W/m{sup 2}K (R-12 to R-0.2 insulation) to prevent overheating of the catalyst. A prototype was installed in a Dodge Neon with a 2.0-liter engine. Following a standard preconditioning and a 23-hour cold soak, an FTP (Federal Test Procedure) emissions test was performed. Although exhaust temperatures during the preconditioning were not hot enough to melt the phase-change material, the vacuum insulation performed well, resulting in a converter temperature of 146{degrees}C after the 23-hour cold soak at 27{degrees}C. Compared to the same converter at ambient conditions, overall emissions of CO and HC were reduced by 52 % and 29 %, to 0.27 and 0.037 g/mile, respectively. The maximum converter temperature during the FTP cycle was 720{degrees}C. This limited testing was performed with a nearly-fresh palladium-only catalyst, but demonstrates the potential of this vacuum insulation approach for emissions reduction and thermal control. Further testing is ongoing. An initial assessment of several production issues is made, including high-volume fabrication challenges, durability, and cost.

Burch, S D; Potter, T F; Keyser, M A [National Renewable Energy Lab., Golden, CO (United States); Brady, M J; Michaels, K F [Chrysler Corp. (United States)

1995-01-01

199

Waste management activities and carbon emissions in Africa  

SciTech Connect

This paper summarizes research into waste management activities and carbon emissions from territories in sub-Saharan Africa with the main objective of quantifying emission reductions (ERs) that can be gained through viable improvements to waste management in Africa. It demonstrates that data on waste and carbon emissions is poor and generally inadequate for prediction models. The paper shows that the amount of waste produced and its composition are linked to national Gross Domestic Product (GDP). Waste production per person is around half that in developed countries with a mean around 230 kg/hd/yr. Sub-Saharan territories produce waste with a biogenic carbon content of around 56% (+/-25%), which is approximately 40% greater than developed countries. This waste is disposed in uncontrolled dumps that produce large amounts of methane gas. Greenhouse gas (GHG) emissions from waste will rise with increasing urbanization and can only be controlled through funding mechanisms from developed countries.

Couth, R. [University of KwaZulu-Natal, CRECHE, School of Civil Engineering, Survey and Construction, Durban 4041 (South Africa); Trois, C., E-mail: troisc@ukzn.ac.za [University of KwaZulu-Natal, CRECHE, School of Civil Engineering, Survey and Construction, Durban 4041 (South Africa)

2011-01-15

200

Carbon dioxide emissions from international air freight  

NASA Astrophysics Data System (ADS)

Greenhouse gas emissions from international air transport were excluded from reduction targets under the Kyoto Protocol, partly because of difficulties with quantifying and apportioning such emissions. Although there has been a great deal of recent research into calculating emissions from aeroplane operations globally, publicly available emissions factors for air freight emissions are scarce. This paper presents a methodology to calculate the amount of fuel burnt and the resulting CO 2 emissions from New Zealand's internationally air freighted imports and exports in 2007. This methodology could be applied to other nations and/or regions. Using data on fuel uplift, air freight and air craft movements, and assumptions on mean passenger loadings and the mass of passengers and air freight, CO 2 emissions factors of 0.82 kg CO 2 per t-km and 0.69 kg CO 2 per t-km for short-haul and long-haul journeys, respectively, were calculated. The total amount of fuel consumed for the international air transport of New Zealand's imports and exports was calculated to be 0.21 Mt and 0.17 Mt respectively, with corresponding CO 2 emissions of 0.67 Mt and 0.53 Mt.

Howitt, Oliver J. A.; Carruthers, Michael A.; Smith, Inga J.; Rodger, Craig J.

2011-12-01

201

[Carbon capture and storage (CCS) and its potential role to mitigate carbon emission in China].  

PubMed

Carbon capture and storage (CCS) has been widely recognized as one of the options to mitigate carbon emission to eventually stabilize carbon dioxide concentration in the atmosphere. Three parts of CCS, which are carbon capture, transport, and storage are assessed in this paper, covering comparisons of techno-economic parameters for different carbon capture technologies, comparisons of storage mechanism, capacity and cost for various storage formations, and etc. In addition, the role of CCS to mitigate global carbon emission is introduced. Finally, China MARKAL model is updated to include various CCS technologies, especially indirect coal liquefaction and poly-generation technologies with CCS, in order to consider carbon emission reduction as well as energy security issue. The model is used to generate different scenarios to study potential role of CCS to mitigate carbon emissions by 2050 in China. It is concluded that application of CCS can decrease marginal abatement cost and the decrease rate can reach 45% for the emission reduction rate of 50%, and it can lessen the dependence on nuclear power development for stringent carbon constrains. Moreover, coal resources can be cleanly used for longer time with CCS, e.g., for the scenario C70, coal share in the primary energy consumption by 2050 will increase from 10% when without CCS to 30% when with CCS. Therefore, China should pay attention to CCS R&D activities and to developing demonstration projects. PMID:17674718

Chen, Wen-Ying; Wu, Zong-Xin; Wang, Wei-Zhong

2007-06-01

202

Propagation of uncertainty in carbon emission scenarios through the global carbon cycle  

SciTech Connect

The authors used the GLOCO model, which is a carbon cycling model that considers seven terrestrial biomes, two oceans and one atmosphere, to evaluate the rise in atmospheric CO[sub 2] concentration, (pCO[sub 2]) and the partitioning of carbon to the global compartments (ocean, atmosphere and terrestrial) as a function of time for a number of possible anthropogenic carbon emission scenarios, based on different energy policies as developed by the Energy Modeling Forum (EMF-12). The authors then evaluated the possible uncertainty in carbon emission scenarios and the propagation of this uncertainty in carbon emission scenarios and the propagation of this uncertainty throughout the model to obtain an envelope for the rise in pCO[sub 2]. Large fluctuations in the input signal are smoothed by the carbon cycle, resulting in more than a four-fold reduction in uncertainty in the output signal (pCO[sub 2]). In addition, they looked at the effect that other model variables have on the pCO[sub 2] envelope, specifically the ratio of carbon to nitrogen in the emissions. The carbon to nitrogen ratio (C:N) will vary throughout the next century depending on the mix on energy sources chosen. More nitrogen in the emissions can produce a cofertilization effect in the terrestrial biomes, which would lead to sequestration of additional carbon. The uncertainty in C:N will enlarge the pCO[sub 2] uncertainty envelope by up to 20 ppm.

Keller, A.A.; Goldstein, R.A. (Electric Power Research Inst., Palo Alto, CA (United States))

1994-09-01

203

Constructing Ag nanoparticles-single wall carbon hybrid nanostructure to improve field emission properties  

NASA Astrophysics Data System (ADS)

The overall process of field emission can be dominated by the contact resistance between the single wall carbon nanotubes (SWCNTs) and the substrate. In order to reduce the contact resistance, we present a wet chemical process of constructing Ag-SWCNTs hybrid nanostructure. Constructing Ag-SWCNTs emitters could improve the electrical contact by increasing the contact area between SWCNTs and substrate. Contact resistance is greatly reduced compared to that of pristine SWCNTs. Field emission properties of Ag-SWCNTs hybrid emitters including current density and emitting image are remarkably improved. Field emission properties based on the modified Fowler-Nordheim (F-N) equation are discussed. Our studies show that this method can enhance the field emission properties of the SWCNTs by improving the contact resistance and is a promising way for mass production of SWCNTs for field emission display.

Chen, Leifeng; Wang, Lei; Yu, Xuegong; Zhang, Shijun; Li, Dan; Xu, Chen; Zeng, Lingsheng; Zhou, Shu; Zhao, Jianjing; Guo, Fan; Hu, Liqin; Yang, Deren

2013-01-01

204

RESULTS FROM THE U.S. DOE 2006 SAVE ENERGY NOW ASSESSMENT INITIATIVE: DOE's Partnership with U.S. Industry to Reduce Energy Consumption, Energy Costs, and Carbon Dioxide Emissions  

SciTech Connect

In the wake of Hurricane Katrina and other severe storms in 2005, natural gas supplies were restricted, prices rose, and industry sought ways to reduce its natural gas use and costs. In October 2005, U.S. Department of Energy (DOE) Energy Secretary Bodman launched his Easy Ways to Save Energy campaign with a promise to provide energy assessments to 200 of the largest U.S. manufacturing plants. A major thrust of the campaign was to ensure that the nation's natural gas supplies would be adequate for all Americans, especially during home heating seasons. In a presentation to the National Press Club on October 3, 2005, Secretary Bodman said: 'America's businesses, factories, and manufacturing facilities use massive amounts of energy. To help them during this period of tightening supply and rising costs, our Department is sending teams of qualified efficiency experts to 200 of the nation's most energy-intensive factories. Our Energy Saving Teams will work with on-site managers on ways to conserve energy and use it more efficiently.' DOE's Industrial Technologies Program (ITP) responded to the Secretary's campaign with its Save Energy Now initiative, featuring a new and highly cost-effective form of energy assessments. The approach for these assessments drew heavily on the existing resources of ITP's Technology Delivery component. Over the years, ITP-Technology Delivery had worked with industry partners to assemble a suite of respected software decision tools, proven assessment protocols, training curricula, certified experts, and strong partnerships for deployment. Because of the program's earlier activities and the resources that had been developed, ITP was prepared to respond swiftly and effectively to the sudden need to promote improved industrial energy efficiency. Because of anticipated supply issues in the natural gas sector, the Save Energy Now initiative strategically focused on natural gas savings and targeted the nation's largest manufacturing plants--those that consume a total of 1 trillion British thermal units (Btu) or more annually. The approximately 6800 U.S. facilities that fall into this category collectively account for about 53% of all energy consumed by industry in the United States. The 2006 Save Energy Now energy assessments departed from earlier DOE plant assessments by concentrating solely on steam and process heating systems, which are estimated to account for approximately 74% of all natural gas use for manufacturing. The assessments also integrated a strong training component designed to teach industrial plant personnel how to use DOE's steam or process heating opportunity assessment software tools. This approach had the advantages of promoting strong buy-in of plant personnel for the assessment and its outcomes and preparing them better to independently replicate the assessment process at the company's other facilities. The Save Energy Now initiative also included provisions to help plants that applied for but did not qualify for assessments (based on the 1 trillion Btu criterion). Services offered to these plants included (1) an assessment by one of DOE's 26 university-based Industrial Assessment Centers (IACs), (2) a telephone consultation with a systems expert at the DOE's Energy Efficiency and Renewable Energy Information Center, or (3) other technical materials and services available through ITP (e.g., the Save Energy Now CD). By the end of 2006, DOE had completed all 200 of the promised assessments, identifying potential natural gas savings of more than 50 trillion Btu and energy cost savings of about $500 million. These savings, if fully implemented, could reduce CO2 emissions by 4.04 million metric tons annually. These results, along with the fact that a large percentage of U.S. energy is used by a relatively small number of very large plants, clearly suggest that assessments are an expedient and cost-effective way to significantly affect large amounts of energy use. Building on the success of the 2006 initiative, ITP has expanded the effort in 2007 with the goal of conducting 250 more asse

Wright, Anthony L [ORNL; Martin, Michaela A [ORNL; Gemmer, Bob [U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy; Scheihing, Paul [U.S. Department of Energy, Industrial Technologies Program; Quinn, James [U.S. Department of Energy

2007-09-01

205

Phosphorus-Assisted Biomass Thermal Conversion: Reducing Carbon Loss and Improving Biochar Stability  

PubMed Central

There is often over 50% carbon loss during the thermal conversion of biomass into biochar, leading to it controversy for the biochar formation as a carbon sequestration strategy. Sometimes the biochar also seems not to be stable enough due to physical, chemical, and biological reactions in soils. In this study, three phosphorus-bearing materials, H3PO4, phosphate rock tailing (PRT), and triple superphosphate (TSP), were used as additives to wheat straw with a ratio of 1: 0.40.8 for biochar production at 500C, aiming to alleviate carbon loss during pyrolysis and to increase biochar-C stabilization. All these additives remarkably increased the biochar yield from 31.7% (unmodified biochar) to 46.9%56.9% (modified biochars). Carbon loss during pyrolysis was reduced from 51.7% to 35.5%47.7%. Thermogravimetric analysis curves showed that the additives had no effect on thermal stability of biochar but did enhance its oxidative stability. Microbial mineralization was obviously reduced in the modified biochar, especially in the TSP-BC, in which the total CO2 emission during 60-d incubation was reduced by 67.8%, compared to the unmodified biochar. Enhancement of carbon retention and biochar stability was probably due to the formation of meta-phosphate or C-O-PO3, which could either form a physical layer to hinder the contact of C with O2 and bacteria, or occupy the active sites of the C band. Our results indicate that pre-treating biomass with phosphors-bearing materials is effective for reducing carbon loss during pyrolysis and for increasing biochar stabilization, which provides a novel method by which biochar can be designed to improve the carbon sequestration capacity. PMID:25531111

Zhao, Ling; Cao, Xinde; Zheng, Wei; Kan, Yue

2014-01-01

206

Carbon Dioxide Emission Factors for Coal  

EIA Publications

The Energy Information Administration (EIA) has developed factors for estimating the amount of carbon dioxide emitted, accounting for differences among coals, to reflect the changing "mix" of coal in U.S. coal consumption.

1994-01-01

207

A carbon budget of Arizona: Comparing Natural Ecosystems with Emissions from Human Activities  

NASA Astrophysics Data System (ADS)

A carbon budget of Arizona was constructed to examine the potential for carbon uptake by the state's ecosystems to mitigate human-caused emissions of greenhouse gases. The NASA-CASA (Carnegie Ames Stanford Approach) carbon flux model was used to estimate annual ecosystem CO2 exchange and the State's 2006 greenhouse gas inventory provided data on emissions from transportation, industry, waste, agriculture, electricity, industrial, and residential fuel use. The net carbon flux from primary production in the eight major land resource areas in the state averaged -1.56 million metric tons of carbon (MMTC) per year between 2001 and 2004. This net uptake from the atmosphere amounts to only 1.5% of statewide anthropogenic emissions of 99 MMTCE per year. Given this large imbalance and that projected climate trends for the region are likely to reduce C stocks in the state's forest and woodland ecosystems, land management to promote ecosystem carbon uptake is not a realistic solution to mitigate Arizona's anthropogenic greenhouse gas emissions.

Ford, A. C.; Finley, B. K.; Koch, G. W.; Hungate, B. A.

2011-12-01

208

Systems accounting for energy consumption and carbon emission by building  

NASA Astrophysics Data System (ADS)

The method of systems accounting for overall energy consumption and carbon emission induced by a building is illustrated in terms of a combination of process and input-output analyses with a concrete procedure to cover various material, equipment, energy and manpower inputs. A detailed case study based on raw project data in the Bill of Quantities (BOQ) is performed for the structure engineering of the landmark buildings in E-town, Beijing (Beijing Economic-Technological Development Area). Based on the embodied energy and carbon emission intensity database for the Chinese economy in 2007, the energy consumption and the carbon emission of the structure engineering of the case buildings are quantified as 4.15E+14 J and 4.83E+04 t CO2 Eq., corresponding to intensities of 6.91E+09 J/m2 and 0.81 t CO2 Eq./m2 floor area. Steel and concrete contribute respectively about 50% and 30% of the energy consumption and the carbon emission, as a result of the reinforced-concrete structure of the case buildings. Materials contribute up to about 90% of the total energy consumption and carbon emission, in contrast to manpower, energy and equipment around 8%, 1% and 0.1%, respectively.

Shao, Ling; Chen, G. Q.; Chen, Z. M.; Guo, Shan; Han, M. Y.; Zhang, Bo; Hayat, T.; Alsaedi, A.; Ahmad, B.

2014-06-01

209

Temperature dependent field emission behavior of carbon nanotube emitters  

NASA Astrophysics Data System (ADS)

Vertically aligned multi-walled carbon nanotubes (MWCNTs) were synthesized on Ni-coated Si substrates by thermal chemical vapor deposition, and then, the field emission behavior of the MWCNTs were investigated with increasing temperature. Before the field emission measurements, a high voltage annealing was carried out for the emitters, which resulted in the formation of defective layer at the emitting tips. We have observed largely increased emission currents and non-linear Fowler-Nordheim (F-N) plots at high temperatures. We propose that these unusual field emission behaviors are attributed to the defective layers formed on MWCNT tips by high voltage annealing.

Lim, Seong Chu; Choi, Young Chul

2013-12-01

210

Evaluation of carbon dioxide emission control strategies in New York State  

SciTech Connect

A MARKAL model was developed for the State of New York. It represents the state's energy system as a set of typical technologies for generating, converting, and using energy as it evolves over a 45-year period. NYMARKAL was applied here in demonstration analyses to explore strategies to reduce CO{sub 2} emissions. NYMARKAL was installed at the State Energy Office and in the Offices of the New York Power Pool. Staff members from both organizations and other state agencies were trained in its use. Example scenarios showed that it is more difficult and more expensive to reduce carbon emissions in New York State than in the United States as a whole. Were a common carbon tax instituted, it would have less effect in New York and most carbon emissions reduction would take place elsewhere in the country where it is more cost-effective. Alternatively, were all states required to reduce CO{sub 2} emission an equal percentage (say by 20%), the cost per unit emissions reduction to New York would be much greater than in the rest of the country.

Morris, S.C.; Lee, J.; Goldstein, G.; Hill, D.

1992-01-01

211

Evaluation of carbon dioxide emission control strategies in New York State. Final report, 1990--1991  

SciTech Connect

A MARKAL model was developed for the State of New York. It represents the state`s energy system as a set of typical technologies for generating, converting, and using energy as it evolves over a 45-year period. NYMARKAL was applied here in demonstration analyses to explore strategies to reduce CO{sub 2} emissions. NYMARKAL was installed at the State Energy Office and in the Offices of the New York Power Pool. Staff members from both organizations and other state agencies were trained in its use. Example scenarios showed that it is more difficult and more expensive to reduce carbon emissions in New York State than in the United States as a whole. Were a common carbon tax instituted, it would have less effect in New York and most carbon emissions reduction would take place elsewhere in the country where it is more cost-effective. Alternatively, were all states required to reduce CO{sub 2} emission an equal percentage (say by 20%), the cost per unit emissions reduction to New York would be much greater than in the rest of the country.

Morris, S.C.; Lee, J.; Goldstein, G.; Hill, D.

1992-01-01

212

Maximum warming occurs about one decade after a carbon dioxide emission  

NASA Astrophysics Data System (ADS)

It is known that carbon dioxide emissions cause the Earth to warm, but no previous study has focused on examining how long it takes to reach maximum warming following a particular CO2 emission. Using conjoined results of carbon-cycle and physical-climate model intercomparison projects (Taylor et al 2012, Joos et al 2013), we find the median time between an emission and maximum warming is 10.1 years, with a 90% probability range of 6.630.7 years. We evaluate uncertainties in timing and amount of warming, partitioning them into three contributing factors: carbon cycle, climate sensitivity and ocean thermal inertia. If uncertainty in any one factor is reduced to zero without reducing uncertainty in the other factors, the majority of overall uncertainty remains. Thus, narrowing uncertainty in century-scale warming depends on narrowing uncertainty in all contributing factors. Our results indicate that benefit from avoided climate damage from avoided CO2 emissions will be manifested within the lifetimes of people who acted to avoid that emission. While such avoidance could be expected to benefit future generations, there is potential for emissions avoidance to provide substantial benefit to current generations.

Ricke, Katharine L.; Caldeira, Ken

2014-12-01

213

Hestia Software Measures Urban Carbon Dioxide Emissions  

NSDL National Science Digital Library

This short video describes the Hestia project - a software tool and data model that provide visualizations of localized CO2 emissions from residential, commercial, and vehicle levels, as well as day versus night comparisons, in the city of Indianapolis.

Kevin Gurney

214

Dielectric barrier discharge carbon atomic emission spectrometer: universal GC detector for volatile carbon-containing compounds.  

PubMed

It was found that carbon atomic emission can be excited in low temperature dielectric barrier discharge (DBD), and an atmospheric pressure, low power consumption, and compact microplasma carbon atomic emission spectrometer (AES) was constructed and used as a universal and sensitive gas chromatographic (GC) detector for detection of volatile carbon-containing compounds. A concentric DBD device was housed in a heating box to increase the plasma operation temperature to 300 C to intensify carbon atomic emission at 193.0 nm. Carbon-containing compounds directly injected or eluted from GC can be decomposed, atomized, and excited in this heated DBD for carbon atomic emission. The performance of this new optical detector was first evaluated by determination of a series of volatile carbon-containing compounds including formaldehyde, ethyl acetate, methanol, ethanol, 1-propanol, 1-butanol, and 1-pentanol, and absolute limits of detection (LODs) were found at a range of 0.12-0.28 ng under the optimized conditions. Preliminary experimental results showed that it provided slightly higher LODs than those obtained by GC with a flame ionization detector (FID). Furthermore, it is a new universal GC detector for volatile carbon-containing compounds that even includes those compounds which are difficult to detect by FID, such as HCHO, CO, and CO2. Meanwhile, hydrogen gas used in conventional techniques was eliminated; and molecular optical emission detection can also be performed with this GC detector for multichannel analysis to improve resolution of overlapped chromatographic peaks of complex mixtures. PMID:24328147

Han, Bingjun; Jiang, Xiaoming; Hou, Xiandeng; Zheng, Chengbin

2014-01-01

215

The cost-effectiveness of remote sensing and repair in reducing motor vehicle nitrogen oxide emissions  

SciTech Connect

Ozone and carbon monoxide remain serious air quality problems in many urban areas throughout the US, and motor vehicles are significant contributors. In response to these problems, the 1990 Clean Air Act Amendments required many areas of the country to implement motor vehicle inspection and maintenance (I/M) programs and adopt the use of reformulated gasoline. These programs have not been well received by the general public, and their effectiveness is currently a source of debate in the scientific community. On-road, remote sensing studies of vehicle emissions have shown that vehicle emissions tend to follow a gamma distribution with up to 50% of vehicle emissions coming from only 10% of the vehicle fleet. Instead of subjecting all vehicles to a control program such as I/M or reformulated gas, it has been suggested that remote sensors could be used to identify high-emitting vehicles and target them for repair. Such remote sensing and repair (RS and R) programs have been shown to be cost-effective methods for reducing carbon monoxide and hydrocarbon emissions. It is not clear, however, if such a program would be a cost-effective method for controlling emissions of nitrogen oxides. In this paper, the authors evaluate the potential for using a NO{sub x}-RS and R program as an urban ozone control strategy in a NO{sub x}-limited airshed, specifically Charlotte, NC. They estimate the cost-effectiveness of a potential NO{sub x}-RS and R program and compare it to other NO{sub X} control strategies for mobile and point sources which have been proposed for Charlotte. RS and R is shown to be relatively expensive, but within the range of the cost effectiveness estimates for the control measures proposed for Charlotte. In the future as inexpensive control measures are exhausted and remote sensing technology improves, RS and R promises to be an excellent alternative for controlling NO{sub x} emissions.

Keating, T.J. [Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Environmental Sciences and Engineering; Taylor, J.D. [Hicks and Associates, Inc., Austin, TX (United States)

1997-12-31

216

40 CFR 1036.610 - Innovative technology credits and adjustments for reducing greenhouse gas emissions.  

Code of Federal Regulations, 2014 CFR

...in-use emissions without the technology. Adjust the emission results...judgment indicates that the actual benefit will be proportional to emissions...this part. For example, the benefits from technologies that reduce engine...

2014-07-01

217

Interactive effects of environmental change and management strategies on regional forest carbon emissions.  

PubMed

Climate mitigation activities in forests need to be quantified in terms of the long-term effects on forest carbon stocks, accumulation, and emissions. The impacts of future environmental change and bioenergy harvests on regional forest carbon storage have not been quantified. We conducted a comprehensive modeling study and life-cycle assessment of the impacts of projected changes in climate, CO2 concentration, and N deposition, and region-wide forest management policies on regional forest carbon fluxes. By 2100, if current management strategies continue, then the warming and CO2 fertilization effect in the given projections result in a 32-68% increase in net carbon uptake, overshadowing increased carbon emissions from projected increases in fire activity and other forest disturbance factors. To test the response to new harvesting strategies, repeated thinnings were applied in areas susceptible to fire to reduce mortality, and two clear-cut rotations were applied in productive forests to provide biomass for wood products and bioenergy. The management strategies examined here lead to long-term increased carbon emissions over current harvesting practices, although semiarid regions contribute little to the increase. The harvest rates were unsustainable. This comprehensive approach could serve as a foundation for regional place-based assessments of management effects on future carbon sequestration by forests in other locations. PMID:24138534

Hudiburg, Tara W; Luyssaert, Sebastiaan; Thornton, Peter E; Law, Beverly E

2013-11-19

218

Very Stable Electron Field Emission From Strontium Titanate Coated Carbon Nanotube Matrices With Low Emission Thresholds  

SciTech Connect

PMMA-STO-CNT matrices were created by opened-tip vertically-aligned multiwalled carbon nanotubes (VA-MWCNTs) with conformal coating of strontium titanate and Poly(methyl methacrylate). Emission threshold of 0.8 V/?m was demonstrated, about five-fold lower than that of the as-grown VAMWCNTs. Theoretical simulation and modeling suggest that PMMA-STO-CNT matrices have suppressed screening effects and Coulombs repulsion forces between electrons in adjacent CNTs, leading to low emission threshold, high emission density, and prolong emission stability. These findings are important for practical application of VA-MWCNTs in field emission devices.

Pandey, Archana; Prasad, Abhishek; Moscatello, Jason; Engelhard, Mark H.; Wang, Chong M.; Yap, Yoke K.

2013-01-22

219

Accounting for Carbon Dioxide Emissions from Bioenergy Systems  

SciTech Connect

Researchers have recently argued that there is a 'critical climate accounting error' and that we should say 'goodbye to carbon neutral' for bioenergy. Many other analysts have published opionions on the same topic, and the US Environmental Protection Agency posted a specific call for information. The currently burning questions for carbon accounting is how to deal with bioenergy. The questions arises because, unlike for fossil fuels, burning of biomass fuels represents part of a cycle in which combustion releases back to the atmosphere carbon that was earlier removed from the atmosphere by growing plants. In a sustainable system, plants will again remove the carbon dioxide (CO{sub 2}) from the atmosphere. Conceptually, it is clear that there are no net emissions of the greenhouse gas CO{sub 2} if biomass is harvested and combusted at the same rate that biomass grows and removes CO{sub 2} from the atmosphere. The problem lies in the fact that growth and combustion do not occur at the same time or in the same place, and our accounting system boundaries - spatial and temporal - frequently do not provide full and balanced accounting. When the first comprehensive guidelines for estimating national greenhouse gas emissions and sinks were put together by the Organization for Economic Cooperation and Development, they noted that it has been argued that CO{sub 2} emissions resulting from bioenergy consumption should not be included in a country's official emission inventory because there are no net emissions if the biomass is produced sustainably, and if the biomass is not produced sustainably, the loss of carbon will be captured as part of the accounting for emissions from land-use change. In the same philosophical vein, the Kyoto Protocol provides that emissions or sinks of CO{sub 2} from land-use change and forestry activities be measured as the 'verifiable changes in carbon stocks'. From these has grown the convention that emissions from biomass fuels are generally not counted as part of emissions inventories, and biomass energy is sometimes referred to as being 'carbon neutral.' But what happens when a forest is harvested for fuel but takes 60 years to regrow or when biomass is harvested in a country that is not party to an international accord but is burned in a country that is party to an international accord? Biomass energy is only truly 'carbon neutral' if we get the system boundaries right. They need to make sure that the accounting methodology is compatible with our needs and realities in management and policy.

Marland, Gregg [ORNL

2010-12-01

220

Synthesis and thermionic emission properties of graphitic carbon nanofibres supported on Si wafers or carbon felt  

NASA Astrophysics Data System (ADS)

Preparation procedures and thermionic emission properties of graphitic carbon nanofibres (GCNFs) supported on Si wafer or commercial carbon felt supports are reported. GCNF/native-oxide Si wafer, GCNF/oxidized Si wafer, GCNF/Ni-coated Si wafer and GCNF/carbon felt nanocomposites are obtained by growing GCNFs from growth catalyst nanoparticles supported on these supports. Narrow herringbone GCNF/SiO2/carbon felt mats are prepared from growth catalyst nanoparticles supported on fumed silica flakes. Due to weak GCNF-to-support binding in GCNF/Si wafer mats, GCNF/carbon felt mats and GCNF/SiO2/carbon felt mats, mechanical loss of the GCNF component is facile. However, carbothermal reduction of GCNF/SiO2/carbon felt nanocomposites affords mechanically robust GCNF/SiC/carbon felt mats. Thermionic electron energy distribution profiles recorded for these new nanofibre compositions indicate classic free-electron emission with estimated work functions (4.25-4.91 eV) slightly lower than those observed for un-doped graphite or carbon nanotubes. Electron energy distributions along the low energy leading region of the profiles display a cascade of emission peaks equally spaced by ca 0.014 eV, tentatively attributed to electron emission from localized GCNF edge sites.

Li, Jiang; Robinson, Vance S.; Liu, Yang; Lu, Weijie; Fisher, Timothy S.; Lukehart, Charles M.

2007-08-01

221

Carbon stars with alpha-C:H emission  

NASA Technical Reports Server (NTRS)

Many carbon stars in the IRS low resolution spectra (LRS) catalog were found which display emission spectra that compare favorable with the absorption spectrum of alpha-C:H. These stars have largely been classified as 4X in the LRS which has led to their interpretation by others in terms of displaying a mixture of the UIRF's 8.6 micron band and SiC at 11.5 microns. It was also found that many of these stars have a spectral upturn at 20+ microns which resembles the MgS band seen in carbon stars and planetary nebulae. It was concluded that this group of carbon stars will evolve into planetary nebulae like NGC 7027 and IC 418. In the presence of hard ultraviolet radiation the UIRF's will light up and be displayed as narrow emission bands on top of the broad alpha-C:H emission bands.

Gerbault, Florence; Goebel, John H.

1989-01-01

222

Carbon emissions from spring 1998 fires in tropical Mexico  

SciTech Connect

The authors used NOAA-AVHRR satellite imagery, biomass density maps, fuel consumption estimates, and a carbon emission factor to estimate the total carbon (C) emissions from the Spring 1998 fires in tropical Mexico. All eight states in southeast Mexico were affected by the wildfires, although the activity was concentrated near the common border of Oaxaca, Chiapas, and Veracruz. The fires burned approximately 482,000 ha and the land use/land cover classes most extensively impacted were the tall/medium selvas (tropical evergreen forests), open/fragmented forests, and perturbed areas. The total prompt emissions were 4.6 TgC during the two-month period of the authors` study, contributing an additional 24% to the region`s average annual net C emissions from forestry and land-use change. Mexico in 1998 experienced its driest Spring since 1941, setting the stage for the widespread burning.

Cairns, M.A.; Hao, W.M.; Alvarado, E.; Haggerty, P.K.

1999-04-01

223

Estimating Global Blue Carbon Emissions from Conversion and Degradation of Vegetated Coastal Ecosystems  

PubMed Central

Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystemsmarshes, mangroves, and seagrassesthat may be lost with habitat destruction (conversion). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this blue carbon can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.151.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 319% of those from deforestation globally, and result in economic damages of $US 642 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats. PMID:22962585

Murray, Brian C.; Crooks, Stephen; Jenkins, W. Aaron; Sifleet, Samantha; Craft, Christopher; Fourqurean, James W.; Kauffman, J. Boone; Marb, Nria; Megonigal, Patrick; Pidgeon, Emily; Herr, Dorothee; Gordon, David; Baldera, Alexis

2012-01-01

224

Estimating global "blue carbon" emissions from conversion and degradation of vegetated coastal ecosystems.  

PubMed

Recent attention has focused on the high rates of annual carbon sequestration in vegetated coastal ecosystems--marshes, mangroves, and seagrasses--that may be lost with habitat destruction ('conversion'). Relatively unappreciated, however, is that conversion of these coastal ecosystems also impacts very large pools of previously-sequestered carbon. Residing mostly in sediments, this 'blue carbon' can be released to the atmosphere when these ecosystems are converted or degraded. Here we provide the first global estimates of this impact and evaluate its economic implications. Combining the best available data on global area, land-use conversion rates, and near-surface carbon stocks in each of the three ecosystems, using an uncertainty-propagation approach, we estimate that 0.15-1.02 Pg (billion tons) of carbon dioxide are being released annually, several times higher than previous estimates that account only for lost sequestration. These emissions are equivalent to 3-19% of those from deforestation globally, and result in economic damages of $US 6-42 billion annually. The largest sources of uncertainty in these estimates stems from limited certitude in global area and rates of land-use conversion, but research is also needed on the fates of ecosystem carbon upon conversion. Currently, carbon emissions from the conversion of vegetated coastal ecosystems are not included in emissions accounting or carbon market protocols, but this analysis suggests they may be disproportionally important to both. Although the relevant science supporting these initial estimates will need to be refined in coming years, it is clear that policies encouraging the sustainable management of coastal ecosystems could significantly reduce carbon emissions from the land-use sector, in addition to sustaining the well-recognized ecosystem services of coastal habitats. PMID:22962585

Pendleton, Linwood; Donato, Daniel C; Murray, Brian C; Crooks, Stephen; Jenkins, W Aaron; Sifleet, Samantha; Craft, Christopher; Fourqurean, James W; Kauffman, J Boone; Marb, Nria; Megonigal, Patrick; Pidgeon, Emily; Herr, Dorothee; Gordon, David; Baldera, Alexis

2012-01-01

225

Options to reduce greenhouse gas emissions during wastewater treatment for agricultural use.  

PubMed

Treatment of primarily-domestic sewage wastewater involves on-site greenhouse gas (GHG) emissions due to energy inputs, organic matter degradation and biological nutrient removal (BNR). BNR causes both direct emissions and loss of fertilizer value, thus eliminating possible reduction of emissions caused by fertilizer manufacture. In this study, we estimated on-site GHG emissions under different treatment scenarios, and present options for emission reduction by changing treatment methods, avoiding BNR and by recovering energy from biogas. Given a typical Israeli wastewater strength (1050mg CODl(-1)), the direct on-site GHG emissions due to energy use were estimated at 1618 and 2102g CO(2)-eq m(-3), respectively, at intermediate and tertiary treatment levels. A potential reduction of approximately 23-55% in GHG emissions could be achieved by fertilizer preservation and VS conversion to biogas. Wastewater fertilizers constituted a GHG abatement potential of 342g CO(2)-eq m(-3). The residual component that remained in the wastewater effluent following intermediate (oxidation ponds) and enhanced (mechanical-biological) treatments was 304-254g CO(2)-eq m(-3) and 65-34g CO(2)-eq m(-3), respectively. Raw sludge constituted approximately 47% of the overall wastewater fertilizers load with an abatement potential of 150g CO(2)-eq m(-3) (385kg CO(2)-eq dry tonne(-1)). Inasmuch as anaerobic digestion reduced it to 63g CO(2)-eq m(-3) (261kg CO(2)-eq dry tonne(-1)), the GHG abatement gained through renewable biogas energy (approx. 428g CO(2)-eq m(-3)) favored digestion. However, sludge composting reduced the fertilizer value to 17g CO(2)-eq m(-3) (121kg CO(2)-eq dry tonne(-1)) or less (if emissions, off-site inputs and actual phytoavailability were considered). Taking Israel as an example, fully exploiting the wastewater derived GHG abatement potential could reduce the State overall GHG emissions by almost 1%. This demonstrates the possibility of optional carbon credits which might be exploited in the construction of new wastewater treatment facilities, especially in developing countries. PMID:22209373

Fine, Pinchas; Hadas, Efrat

2012-02-01

226

Will Monetized Carbon Emission Reductions Buy Enhanced Building Operations?  

E-print Network

- Policies and Measures International and United State Programs - Kyoto Protocol - European Union Emission Trading Scheme - California Global Warming Solutions Act - Regional Greenhouse Gas Initiative #0;z Strategies for Expanding Buildings Role Buildings... to the Country/State Priorities -- Varied, Uncertain Results in Different Jurisdictions State and Trends of the Carbon Market 2007 Source: State Trends of the Carbon Market 2007, The World Bank, pg. 3. Location of CDM Projects Source: State Trends...

Millhone, J.

2007-01-01

227

Insensitivity of global warming potentials to carbon dioxide emission scenarios  

Microsoft Academic Search

GLOBAL warming potentials for radiatively active trace gases (such as methane and chlorofluorocarbons) have generally been expressed1-2 relative to the time-integrated climate forcing per unit emission of carbon dioxide. Previous attempts to estimate the integrated climate forcing per unit CO2 emitted have focused on perturbations to steady-state conditions in carbon-cycle models. But for non-steady-state conditions, the integrated climate forcing from

Ken Caldeira; James F. Kasting

1993-01-01

228

Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials  

PubMed Central

Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102 PMID:21291517

2011-01-01

229

Electricity generation: options for reduction in carbon emissions.  

PubMed

Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO(2) each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO(2) emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO(2) emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of improved combustion technology, the removal of harmful gases from power-station flues and the use of waste heat to improve overall power-station efficiency. These all have a part to play, but many consider our best hope for emissions reduction to be the use of renewable energy. The main renewable energy contenders are assessed in this paper and realistic estimates of the contribution that each could provide are indicated. It appears that, in the time-scale envisaged by planners for reduction in CO(2) emission, in many countries renewable energy will be unlikely to deliver. At the same time, it is worth commenting that, again in many countries, the level of penetration of renewable energy will fall short of the present somewhat optimistic targets. Of renewable options, wind energy could be used in the short to medium term to cover for thermal plant closures, but for wind energy to be successful, the network will have to be modified to cope with wind's intermittent nature. Globally, hydroelectricity is currently the largest developed source of renewable electricity, but future large-scale projects will probably be limited to the less-developed world: the best schemes in the developed countries have already been exploited. Wave and tidal can be looked on as medium- to long-term generators of electricity, as their respective industries are not as mature as competing renewable resources. Municipal solid-waste combustion and landfill gas technologies can also be seen as short term, as can their rural equivalents, agriculture and forestry waste. Any widespread exploitation of renewable energy will depend on being able to transmit the energy from source to point of use, so the implications for the electrical network from the penetration of substantial levels of renewable energy are presented. Effective management of renewable energy installations will require technical assessment of the range of exploitation strategies, to compare local production of, say, hydrogen and the more traditional transmission of electricity. Such resources will have to compete with others in any national, or grid, system and detailed economic analysis will be necessary to determine the deployment that best fits the trading regime under which the energy will be sold. Consideration will also be necessary to determine how best to control the introduction of this radically new resource such that it does not attract punitive cost overheads until it is mature enough to cope. Finally, it is inescapable that nuclear power is a proven technology that could take its place in any future generation portfolio. Unfortunately, suspicion and mistrust surround waste management and radioactivity release. Unless this is overcome, the lack of confidence engendered by this public mistrust may result in few, if any, new nuclear power stations being built. In the event of that decision, it is difficult to see how CO(2) levels can be significantly reduced: the irony is that nuclear energy may emerge as environmentally essential. PMID:12460490

Whittington, H W

2002-08-15

230

Field emission from non-uniform carbon nanotube arrays  

PubMed Central

Regular arrays of carbon nanotubes (CNTs) are frequently used in studies on field emission. However, non-uniformities are always present like dispersions in height, radius, and position. In this report, we describe the effect of these non-uniformities in the overall emission current by simulation. We show that non-uniform arrays can be modeled as a perfect array multiplied by a factor that is a function of the CNTs spacing. PMID:23841961

2013-01-01

231

Using infrastructure optimization to reduce greenhouse gas emissions from oil sands extraction and processing.  

PubMed

The Alberta oil sands are a significant source of oil production and greenhouse gas emissions, and their importance will grow as the region is poised for decades of growth. We present an integrated framework that simultaneously considers economic and engineering decisions for the capture, transport, and storage of oil sands CO(2) emissions. The model optimizes CO(2) management infrastructure at a variety of carbon prices for the oil sands industry. Our study reveals several key findings. We find that the oil sands industry lends itself well to development of CO(2) trunk lines due to geographic coincidence of sources and sinks. This reduces the relative importance of transport costs compared to nonintegrated transport systems. Also, the amount of managed oil sands CO(2) emissions, and therefore the CCS infrastructure, is very sensitive to the carbon price; significant capture and storage occurs only above 110$/tonne CO(2) in our simulations. Deployment of infrastructure is also sensitive to CO(2) capture decisions and technology, particularly the fraction of capturable CO(2) from oil sands upgrading and steam generation facilities. The framework will help stakeholders and policy makers understand how CCS infrastructure, including an extensive pipeline system, can be safely and cost-effectively deployed. PMID:23276202

Middleton, Richard S; Brandt, Adam R

2013-02-01

232

Method for reducing emissions utilizing pre-atomized fuels  

SciTech Connect

A method is described for reducing particulate emissions during combustion of a hydrocarbon with API gravity of about 20/sup 0/ API or less, viscosity of about 40,000 centipoise at 122/sup 0/F, paraffin content of about 50% by weight or less, aromatic content of about 15% by weight or greater, and asphaltene content of about 50% by weight or greater. The method comprises: emulsifying such hydrocarbon to form a hydrocarbon-in-water emulsion having a hydrocarbon water ratio from about 60:40 to about 90:10 by volume and in which emulsion the hydrocarbon has a particle size predominantly of about 50 microns in diameter or less; preheating such hydrocarbon-in-water emulsion prior to combustion; and burning such hydrocarbon-in-water emulsion.

Hayes, M.E.; Hrebenar, K.R.; Deal, J.F. III; Bolden, P.L. Jr.

1987-05-19

233

Carbon emissions risk map from deforestation in the tropical Amazon  

NASA Astrophysics Data System (ADS)

Assis, Pedro Valle This work aims to estimate the carbon emissions from tropical deforestation in the Brazilian Amazon associated to the risk assessment of future land use change. The emissions are estimated by incorporating temporal deforestation dynamics, accounting for the biophysical and socioeconomic heterogeneity in the region, as well secondary forest growth dynamic in abandoned areas. The land cover change model that supported the risk assessment of deforestation, was run based on linear regressions. This method takes into account spatial heterogeneity of deforestation as the spatial variables adopted to fit the final regression model comprise: environmental aspects, economic attractiveness, accessibility and land tenure structure. After fitting a suitable regression models for each land cover category, the potential of each cell to be deforested (25x25km and 5x5 km of resolution) in the near future was used to calculate the risk assessment of land cover change. The carbon emissions model combines high-resolution new forest clear-cut mapping and four alternative sources of spatial information on biomass distribution for different vegetation types. The risk assessment map of CO2 emissions, was obtained by crossing the simulation results of the historical land cover changes to a map of aboveground biomass contained in the remaining forest. This final map represents the risk of CO2 emissions at 25x25km and 5x5 km until 2020, under a scenario of carbon emission reduction target.

Ometto, J.; Soler, L. S.; Assis, T. D.; Oliveira, P. V.; Aguiar, A. P.

2011-12-01

234

Carbon Input and Soil Carbon Dioxide Emission Affected by Land Use and Management Practices  

Technology Transfer Automated Retrieval System (TEKTRAN)

Land use and management practices may influence C inputs and soil CO2 emission, a greenhouse gas responsible for global warming. Carbon inputs and soil CO2 emission were monitored from crop- and grassland with various irrigation and cropping systems from 2006 to 2008 in western North Dakota, USA. Tr...

235

The synthesis and field emission property of carbon nanotubes on carbon fibers substrate  

Microsoft Academic Search

Using ferrocene as catalyst precursor, C2H2 as carbon source, carbon nanotubes (CNTs) with uniform density were synthesized on carbon fibers substrate by floating catalyst method. The morphology and microstructure were characterized by field emission scanning electron microscope (FESEM) and high-resolution transmission electron microscopy (HRTEM). The observation showed that the length of CNTs is about 2 m, the average space between

Leyong Zeng; Weibiao Wang; Jingqiu Liang; Yuxue Xia; Da Lei; Song Chen; Haifeng Zhao

2007-01-01

236

Global carbon dioxide emissions from inland waters.  

PubMed

Carbon dioxide (CO2) transfer from inland waters to the atmosphere, known as CO2 evasion, is a component of the global carbon cycle. Global estimates of CO2 evasion have been hampered, however, by the lack of a framework for estimating the inland water surface area and gas transfer velocity and by the absence of a global CO2 database. Here we report regional variations in global inland water surface area, dissolved CO2 and gas transfer velocity. We obtain global CO2 evasion rates of 1.8(+0.25)(-0.25)? petagrams of carbon (Pg?C) per year from streams and rivers and 0.32(+0.52)(-0.26)? Pg?C?yr(-1) from lakes and reservoirs, where the upper and lower limits are respectively the 5th and 95th confidence interval percentiles. The resulting global evasion rate of 2.1?Pg?C?yr(-1) is higher than previous estimates owing to a larger stream and river evasion rate. Our analysis predicts global hotspots in stream and river evasion, with about 70 per cent of the flux occurring over just 20 per cent of the land surface. The source of inland water CO2 is still not known with certainty and new studies are needed to research the mechanisms controlling CO2 evasion globally. PMID:24256802

Raymond, Peter A; Hartmann, Jens; Lauerwald, Ronny; Sobek, Sebastian; McDonald, Cory; Hoover, Mark; Butman, David; Striegl, Robert; Mayorga, Emilio; Humborg, Christoph; Kortelainen, Pirkko; Drr, Hans; Meybeck, Michel; Ciais, Philippe; Guth, Peter

2013-11-21

237

Field Emission Characteristics of Carbon Nanotubes and Their Applications in Sensors and Devices  

NASA Astrophysics Data System (ADS)

FIELD EMISSION CHARACTERISTICS OF CARBON NANOTUBES AND THEIR APPLICATIONS IN SENSORS AND DEVICES A. Vaseashta, C. Shaffer, M. Collins, A. Mwuara Dept of Physics, Marshall University, Huntington, WV V. Pokropivny Institute for Materials Sciences of NASU, Kiev, Ukraine. D. Dimova-Malinovska Bulgarian Academy of Sciences, Sofia, Bulgaria. The dimensionality of a system has profound influence on its physical behavior. With advances in technology over the past few decades, it has become possible to fabricate and study reduced-dimensional systems, such as carbon nanotubes (CNTs). Carbon nanotubes are especially promising candidate for cold cathode field emitter because of their electrical properties, high aspect ratio, and small radius of curvature at the tips. Electron emission from the carbon nanotubes was investigated. Based upon the field emission investigation of carbon nanotubes, several prototype devices have been suggested that operate with low swing voltages with sufficient high current densities. Characteristics that allow improved current stability and long lifetime operation for electrical and opto-electronics devices are presented. The aim of this brief overview is to illustrate the useful characteristics of carbon nanotubes and its possible application.

Vaseashta, Ashok

2003-03-01

238

Stable carbon isotope fractionation by sulfate-reducing bacteria  

NASA Technical Reports Server (NTRS)

Biogeochemical transformations occurring in the anoxic zones of stratified sedimentary microbial communities can profoundly influence the isotopic and organic signatures preserved in the fossil record. Accordingly, we have determined carbon isotope discrimination that is associated with both heterotrophic and lithotrophic growth of pure cultures of sulfate-reducing bacteria (SRB). For heterotrophic-growth experiments, substrate consumption was monitored to completion. Sealed vessels containing SRB cultures were harvested at different time intervals, and delta(13)C values were determined for gaseous CO(2), organic substrates, and products such as biomass. For three of the four SRB, carbon isotope effects between the substrates, acetate or lactate and CO(2), and the cell biomass were small, ranging from 0 to 2 per thousand. However, for Desulfotomaculum acetoxidans, the carbon incorporated into biomass was isotopically heavier than the available substrates by 8 to 9 per thousand. SRB grown lithoautotrophically consumed less than 3% of the available CO(2) and exhibited substantial discrimination (calculated as isotope fractionation factors [alpha]), as follows: for Desulfobacterium autotrophicum, alpha values ranged from 1.0100 to 1.0123; for Desulfobacter hydrogenophilus, the alpha value was 0.0138, and for Desulfotomaculum acetoxidans, the alpha value was 1.0310. Mixotrophic growth of Desulfovibrio desulfuricans on acetate and CO(2) resulted in biomass with a delta(13)C composition intermediate to that of the substrates. The extent of fractionation depended on which enzymatic pathways were used, the direction in which the pathways operated, and the growth rate, but fractionation was not dependent on the growth phase. To the extent that environmental conditions affect the availability of organic substrates (e.g., acetate) and reducing power (e.g., H(2)), ecological forces can also influence carbon isotope discrimination by SRB.

Londry, Kathleen L.; Des Marais, David J.

2003-01-01

239

China's Energy and Carbon Emissions Outlook to 2050  

E-print Network

LBNL-4472E China's Energy and Carbon Emissions Outlook to 2050 Nan Zhou, David Fridley, Michael McNeil, Nina Zheng, Jing Ke, and Mark Levine China Energy Group Energy Analysis Department Environmental Energy Technologies Division Lawrence Berkeley National Laboratory April 2011 This work was supported by the China

240

Modeling Seasonality in Carbon Dioxide Emissions From Fossil Fuel Consumption  

Microsoft Academic Search

Using United States data, a method is developed to estimate the monthly consumption of solid, liquid and gaseous fossil fuels using monthly sales data to estimate the relative monthly proportions of the total annual national fossil fuel use. These proportions are then used to estimate the total monthly carbon dioxide emissions for each state. From these data, the goal is

P. Kishore; K. Igarashi; H. Oikawa; M. Uotome; J. S. Gregg; R. J. Andres

2004-01-01

241

Field emission characteristics of regular arrays of carbon nanotubes.  

PubMed

The developments of electronic devices based on micron-sized vacuum electron sources during the last decades have triggered intense research on highly efficient carbon based thin film electron emitters. The synthesis of massive arrays of carbon nanotubes that are oriented on patterned Fe catalyst deposited on quartz substrates is reported. The well-ordered nanotubes can be used as electron field emission arrays. Scaling up of the synthesis process should be entirely compatible with the existing semiconductor processes, and should allow the development of nanotubes devices integrated into future technology. The emission from carbon nanotubes array is explained by Fowler-Nordheim tunneling of electrons from tip-like structures in the nanometer range, which locally amplify the applied field by the field enhancement factor beta. We found that the low pressure chemical vapour deposition (LPCVD) system can produce nanotubes capable of excellent emission currents at lower voltages. The carbon nanotubes array shows good field emission with turn on field E(alpha) = 1.30 V/microm at the current density of 3.50 mA/cm2 with enhancement factor beta = 1.22 x 10(2). PMID:24738452

Al-Ghamdi, A A; Al-Heniti, S; Al-Hazmi, F S; Faidah, Adel S; Shalaan, E; Husain, M

2014-06-01

242

SWAMP Project Trip report Quantification of Carbon Stocks and Emissions  

E-print Network

1 SWAMP Project Trip report Quantification of Carbon Stocks and Emissions from the Mangrove Forests (SWAMP). Coastal wetlands in Honduras, particularly mangrove forests provide a broad array of ecosystem strategies. In many areas, mangrove areas converted and utilized for aquaculture (shrimp ponds) and other

Tullos, Desiree

243

Incidence of unilateral consumption taxes on world carbon emissions  

Microsoft Academic Search

This note investigates the suitability of unilateral consumption taxes for alleviating climate change in a two-period two-country general equilibrium model with a finite stock of fossil fuel. We analyze the incidence of a unilateral consumption tax in the first period on world carbon emissions. If countries are identical or if the taxing country imports both fossil fuel and consumption goods

Thomas Eichner; Rdiger Pethig

2011-01-01

244

High-resolution mapping of motor vehicle carbon dioxide emissions  

NASA Astrophysics Data System (ADS)

fuel-based inventory for vehicle emissions is presented for carbon dioxide (CO2) and mapped at various spatial resolutions (10 km, 4 km, 1 km, and 500 m) using fuel sales and traffic count data. The mapping is done separately for gasoline-powered vehicles and heavy-duty diesel trucks. Emission estimates from this study are compared with the Emissions Database for Global Atmospheric Research (EDGAR) and VULCAN. All three inventories agree at the national level within 5%. EDGAR uses road density as a surrogate to apportion vehicle emissions, which leads to 20-80% overestimates of on-road CO2 emissions in the largest U.S. cities. High-resolution emission maps are presented for Los Angeles, New York City, San Francisco-San Jose, Houston, and Dallas-Fort Worth. Sharp emission gradients that exist near major highways are not apparent when emissions are mapped at 10 km resolution. High CO2 emission fluxes over highways become apparent at grid resolutions of 1 km and finer. Temporal variations in vehicle emissions are characterized using extensive day- and time-specific traffic count data and are described over diurnal, day of week, and seasonal time scales. Clear differences are observed when comparing light- and heavy-duty vehicle traffic patterns and comparing urban and rural areas. Decadal emission trends were analyzed from 2000 to 2007 when traffic volumes were increasing and a more recent period (2007-2010) when traffic volumes declined due to recession. We found large nonuniform changes in on-road CO2 emissions over a period of ~5 years, highlighting the importance of timely updates to motor vehicle emission inventories.

McDonald, Brian C.; McBride, Zoe C.; Martin, Elliot W.; Harley, Robert A.

2014-05-01

245

Climate warming feedback from mountain birch forest expansion: reduced albedo dominates carbon uptake.  

PubMed

Expanding high-elevation and high-latitude forest has contrasting climate feedbacks through carbon sequestration (cooling) and reduced surface reflectance (warming), which are yet poorly quantified. Here, we present an empirically based projection of mountain birch forest expansion in south-central Norway under climate change and absence of land use. Climate effects of carbon sequestration and albedo change are compared using four emission metrics. Forest expansion was modeled for a projected 2.6 C increase in summer temperature in 2100, with associated reduced snow cover. We find that the current (year 2000) forest line of the region is circa 100 m lower than its climatic potential due to land-use history. In the future scenarios, forest cover increased from 12% to 27% between 2000 and 2100, resulting in a 59% increase in biomass carbon storage and an albedo change from 0.46 to 0.30. Forest expansion in 2100 was behind its climatic potential, forest migration rates being the primary limiting factor. In 2100, the warming caused by lower albedo from expanding forest was 10 to 17 times stronger than the cooling effect from carbon sequestration for all emission metrics considered. Reduced snow cover further exacerbated the net warming feedback. The warming effect is considerably stronger than previously reported for boreal forest cover, because of the typically low biomass density in mountain forests and the large changes in albedo of snow-covered tundra areas. The positive climate feedback of high-latitude and high-elevation expanding forests with seasonal snow cover exceeds those of afforestation at lower elevation, and calls for further attention of both modelers and empiricists. The inclusion and upscaling of these climate feedbacks from mountain forests into global models is warranted to assess the potential global impacts. PMID:24343906

de Wit, Heleen A; Bryn, Anders; Hofgaard, Annika; Karstensen, Jonas; Kvalevg, Maria M; Peters, Glen P

2014-07-01

246

Carbon emissions from forest conversion by Kalimantan oil palm plantations  

NASA Astrophysics Data System (ADS)

Oil palm supplies >30% of world vegetable oil production. Plantation expansion is occurring throughout the tropics, predominantly in Indonesia, where forests with heterogeneous carbon stocks undergo high conversion rates. Quantifying oil palm's contribution to global carbon budgets therefore requires refined spatio-temporal assessments of land cover converted to plantations. Here, we report oil palm development across Kalimantan (538,346km2) from 1990 to 2010, and project expansion to 2020 within government-allocated leases. Using Landsat satellite analyses to discern multiple land covers, coupled with above- and below-ground carbon accounting, we develop the first high-resolution carbon flux estimates from Kalimantan plantations. From 1990 to 2010, 90% of lands converted to oil palm were forested (47% intact, 22% logged, 21% agroforests). By 2010, 87% of total oil palm area (31,640km2) occurred on mineral soils, and these plantations contributed 61-73% of 1990-2010 net oil palm emissions (0.020-0.024GtCyr-1). Although oil palm expanded 278% from 2000 to 2010, 79% of allocated leases remained undeveloped. By 2020, full lease development would convert 93,844km2 (~ 90% forested lands, including 41% intact forests). Oil palm would then occupy 34% of lowlands outside protected areas. Plantation expansion in Kalimantan alone is projected to contribute 18-22% (0.12-0.15GtCyr-1) of Indonesia's 2020 CO2-equivalent emissions. Allocated oil palm leases represent a critical yet undocumented source of deforestation and carbon emissions.

Carlson, Kimberly M.; Curran, Lisa M.; Asner, Gregory P.; Pittman, Alice Mcdonald; Trigg, Simon N.; Marion Adeney, J.

2013-03-01

247

Analysis of carbon dioxide emission of gas fuelled cogeneration plant  

NASA Astrophysics Data System (ADS)

Gas turbines are widely used for power generation. In cogeneration system, the gas turbine generates electricity and the exhaust heat from the gas turbine is used to generate steam or chilled water. Besides enhancing the efficiency of the system, the process assists in reducing the emission of CO2 to the environment. This study analyzes the amount of CO2 emission by Universiti Teknologi Petronas gas fuelled cogeneration system using energy balance equations. The results indicate that the cogeneration system reduces the CO2 emission to the environment by 60%. This finding could encourage the power plant owners to install heat recovery systems to their respective plants.

Nordin, Adzuieen; Amin, M.; Majid, A.

2013-12-01

248

Black carbon emissions in gasoline exhaust and a reduction alternative with a gasoline particulate filter.  

PubMed

Black carbon (BC) mass and solid particle number emissions were obtained from two pairs of gasoline direct injection (GDI) vehicles and port fuel injection (PFI) vehicles over the U.S. Federal Test Procedure 75 (FTP-75) and US06 Supplemental Federal Test Procedure (US06) drive cycles on gasoline and 10% by volume blended ethanol (E10). BC solid particles were emitted mostly during cold-start from all GDI and PFI vehicles. The reduction in ambient temperature had significant impacts on BC mass and solid particle number emissions, but larger impacts were observed on the PFI vehicles than the GDI vehicles. Over the FTP-75 phase 1 (cold-start) drive cycle, the BC mass emissions from the two GDI vehicles at 0 F (-18 C) varied from 57 to 143 mg/mi, which was higher than the emissions at 72 F (22 C; 12-29 mg/mi) by a factor of 5. For the two PFI vehicles, the BC mass emissions over the FTP-75 phase 1 drive cycle at 0 F varied from 111 to 162 mg/mi, higher by a factor of 44-72 when compared to the BC emissions of 2-4 mg/mi at 72 F. The use of a gasoline particulate filter (GPF) reduced BC emissions from the selected GDI vehicle by 73-88% at various ambient temperatures over the FTP-75 phase 1 drive cycle. The ambient temperature had less of an impact on particle emissions for a warmed-up engine. Over the US06 drive cycle, the GPF reduced BC mass emissions from the GDI vehicle by 59-80% at various temperatures. E10 had limited impact on BC emissions from the selected GDI and PFI vehicles during hot-starts. E10 was found to reduce BC emissions from the GDI vehicle by 15% at standard temperature and by 75% at 19 F (-7 C). PMID:24758145

Chan, Tak W; Meloche, Eric; Kubsh, Joseph; Brezny, Rasto

2014-05-20

249

Shade trees reduce building energy use and CO2 emissions from power plants  

SciTech Connect

Urban shade trees offer significant benefits in reducing building air-conditioning demand and improving urban air quality by reducing smog. The savings associated with these benefits vary by climate region and can be up to $200 per tree. The cost of planting trees and maintaining them can vary from $10 to $500 per tree. Tree-planting programs can be designed to have lower costs so that they offer potential savings to communities that plant trees. Our calculations suggest that urban trees play a major role in sequestering C02 and thereby delay global warming. We estimate that a tree planted in Los Angeles avoids the combustion of 18 kg of carbon annually, even though it sequesters only 4.5-11 kg (as it would if growing in a forest). In this sense, one shade tree in Los Angeles is equivalent to three to five forest trees. In a recent analysis for Baton Rouge, Sacramento, and Salt Lake City, we estimated that planting an average of four shade trees per house (each with a top view cross section of 50 m2) would lead to an annual reduction in carbon emissions from power plants of 16,000, 41,000, and 9000 t, respectively (the per-tree reduction in carbon emissions is about 10-11 kg per year). These reductions only account for the direct reduction in the net cooling- and heating-energy use of buildings. Once the impact of the community cooling is included, these savings are increased by at least 25 percent.

Akbari, H.

2001-11-01

250

Diesel engine development in view of reduced emission standards  

Microsoft Academic Search

Diesel engine development for use in light-, medium- and heavy-duty road vehicles is mainly driven by more and more stringent emission standards. Apart from air quality related emissions such as nitrogen oxides and particulates, also greenhouse gas (GHG) emissions are likely to become of more and more importance. Furthermore, oil-based fuel availability might become a problem due to limited reserves

Walter Knecht

2008-01-01

251

Associations of individual, household and environmental characteristics with carbon dioxide emissions from motorised passenger travel  

PubMed Central

Carbon dioxide (CO2) emissions from motorised travel are hypothesised to be associated with individual, household, spatial and other environmental factors. Little robust evidence exists on who contributes most (and least) to travel CO2 and, in particular, the factors influencing commuting, business, shopping and social travel CO2. This paper examines whether and how demographic, socio-economic and other personal and environmental characteristics are associated with land-based passenger transport and associated CO2 emissions. Primary data were collected from 3474 adults using a newly developed survey instrument in the iConnect study in the UK. The participants reported their past-week travel activity and vehicle characteristics from which CO2 emissions were derived using an adapted travel emissions profiling method. Multivariable linear and logistic regression analyses were used to examine what characteristics predicted higher CO2 emissions. CO2 emissions from motorised travel were distributed highly unequally, with the top fifth of participants producing more than two fifth of emissions. Car travel dominated overall CO2 emissions, making up 90% of the total. The strongest independent predictors of CO2 emissions were owning at least one car, being in full-time employment and having a home-work distance of more than 10km. Income, education and tenure were also strong univariable predictors of CO2 emissions, but seemed to be further back on the causal pathway than having a car. Male gender, late-middle age, living in a rural area and having access to a bicycle also showed significant but weaker associations with emissions production. The findings may help inform the development of climate change mitigation policies for the transport sector. Targeting individuals and households with high car ownership, focussing on providing viable alternatives to commuting by car, and supporting planning and other policies that reduce commuting distances may provide an equitable and efficient approach to meeting carbon mitigation targets. PMID:24882922

Brand, Christian; Goodman, Anna; Rutter, Harry; Song, Yena; Ogilvie, David

2013-01-01

252

Associations of individual, household and environmental characteristics with carbon dioxide emissions from motorised passenger travel.  

PubMed

Carbon dioxide (CO2) emissions from motorised travel are hypothesised to be associated with individual, household, spatial and other environmental factors. Little robust evidence exists on who contributes most (and least) to travel CO2 and, in particular, the factors influencing commuting, business, shopping and social travel CO2. This paper examines whether and how demographic, socio-economic and other personal and environmental characteristics are associated with land-based passenger transport and associated CO2 emissions. Primary data were collected from 3474 adults using a newly developed survey instrument in the iConnect study in the UK. The participants reported their past-week travel activity and vehicle characteristics from which CO2 emissions were derived using an adapted travel emissions profiling method. Multivariable linear and logistic regression analyses were used to examine what characteristics predicted higher CO2 emissions. CO2 emissions from motorised travel were distributed highly unequally, with the top fifth of participants producing more than two fifth of emissions. Car travel dominated overall CO2 emissions, making up 90% of the total. The strongest independent predictors of CO2 emissions were owning at least one car, being in full-time employment and having a home-work distance of more than 10km. Income, education and tenure were also strong univariable predictors of CO2 emissions, but seemed to be further back on the causal pathway than having a car. Male gender, late-middle age, living in a rural area and having access to a bicycle also showed significant but weaker associations with emissions production. The findings may help inform the development of climate change mitigation policies for the transport sector. Targeting individuals and households with high car ownership, focussing on providing viable alternatives to commuting by car, and supporting planning and other policies that reduce commuting distances may provide an equitable and efficient approach to meeting carbon mitigation targets. PMID:24882922

Brand, Christian; Goodman, Anna; Rutter, Harry; Song, Yena; Ogilvie, David

2013-04-01

253

Carbon dioxide and methane emission dynamics in central London (UK)  

NASA Astrophysics Data System (ADS)

London, with a population of 8.2 million, is the largest city in Europe. It is heavily built-up (typically 8% vegetation cover within the central boroughs) and boasts some of the busiest arteries in Europe despite efforts to reduce traffic in the city centre with the introduction of a congestion charging scheme in 2007. We report on two substantial pollution monitoring efforts in the heart of London between October 2006 and present. Fluxes of carbon dioxide (CO2) and water (H2O) were measured continuously by eddy-covariance in central London from October 2006 until May 2008 from a 190 m telecommunication tower (BT tower; 51 31' 17.4'' N 0 8' 20.04'' W). The eddy-covariance system consisted of a Gill R3-50 ultrasonic anemometer operated at 20 Hz and a LI-COR 6262 infrared gas analyser. Air was sampled 0.3 m below the sensor head of the ultrasonic anemometer - which was itself mounted on a 3 m mast to the top of a 15 m lattice tower situated on the roof of the tower (instrument head at 190 m above street level) - and pulled down 45 m of 12.7 mm OD Teflon tubing. In addition, meteorological variables (temperature, relative humidity, pressure, precipitation, wind speed and direction) were also measured with a multi-sensor (Weather Transmitter WXT510, Vaisala). Eddy-covariance measurements at the BT tower location were reinstated in July 2011 and include methane (CH4), CO2 and H2O concentrations measured by a Picarro fast methane analyser (G2301-f). CO2 emissions were found to be mainly controlled by fossil fuel combustion (e.g. traffic, commercial and domestic heating). Diurnal averages of CO2 fluxes were found to be highly correlated to traffic. However changes in heating-related natural gas consumption and, to a lesser extent, photosynthetic activity in two large city centre green spaces (Hyde Park and Regent's Park) explained the seasonal variability. Annual estimates of net exchange of CO2 obtained by eddy-covariance agreed well with up-scaled data from the UK National Atmospheric Emissions Inventory (NAEI) for the flux footprint estimated using a simple Kormann-Meixner model. Methane emissions from central London exhibit diurnal trends both for concentrations and fluxes. The former is consistent with cycles of growth and shrinkage of the urban boundary layer. Methane fluxes are strongly correlated with those of carbon dioxide. Work is ongoing to establish to what extent the diurnal cycles reflect dynamic changes in ground sources (emissions from road traffic, commercial/ domestic heating, variations in flux footprint) and to what extent they are affected by transport efficiency between street level and the top of the tower and storage in between, given the high measurement height.

Helfter, Carole; Nemitz, Eiko; Barlow, Janet F.; Wood, Curtis R.

2013-04-01

254

Thermionic Emission of Single-Wall Carbon Nanotubes Measured  

NASA Technical Reports Server (NTRS)

Researchers at the NASA Glenn Research Center, in collaboration with the Rochester Institute of Technology, have investigated the thermionic properties of high-purity, single-wall carbon nanotubes (SWNTs) for use as electron-emitting electrodes. Carbon nanotubes are a recently discovered material made from carbon atoms bonded into nanometer-scale hollow tubes. Such nanotubes have remarkable properties. An extremely high aspect ratio, as well as unique mechanical and electronic properties, make single-wall nanotubes ideal for use in a vast array of applications. Carbon nanotubes typically have diameters on the order of 1 to 2 nm. As a result, the ends have a small radius of curvature. It is these characteristics, therefore, that indicate they might be excellent potential candidates for both thermionic and field emission.

Landis, Geoffrey A.; Krainsky, Isay L.; Bailey, Sheila G.; Elich, Jeffrey M.; Landi, Brian J.; Gennett, Thomas; Raffaelle, Ryne P.

2004-01-01

255

Grape marc reduces methane emissions when fed to dairy cows.  

PubMed

Grape marc (the skins, seeds, stalk, and stems remaining after grapes have been pressed to make wine) is currently a by-product used as a feed supplement by the dairy and beef industries. Grape marc contains condensed tannins and has high concentrations of crude fat; both these substances can reduce enteric methane (CH4) production when fed to ruminants. This experiment examined the effects of dietary supplementation with either dried, pelleted grape marc or ensiled grape marc on yield and composition of milk, enteric CH4 emissions, and ruminal microbiota in dairy cows. Thirty-two Holstein dairy cows in late lactation were offered 1 of 3 diets: a control (CON) diet; a diet containing dried, pelleted grape marc (DGM); and a diet containing ensiled grape marc (EGM). The diet offered to cows in the CON group contained 14.0kg of alfalfa hay dry matter (DM)/d and 4.3kg of concentrate mix DM/d. Diets offered to cows in the DGM and EGM groups contained 9.0kg of alfalfa hay DM/d, 4.3kg of concentrate mix DM/d, and 5.0kg of dried or ensiled grape marc DM/d, respectively. These diets were offered individually to cows for 18d. Individual cow feed intake and milk yield were measured daily and milk composition measured on 4d/wk. Individual cow CH4 emissions were measured by the SF6 tracer technique on 2d at the end of the experiment. Ruminal bacterial, archaeal, fungal, and protozoan communities were quantified on the last day of the experiment. Cows offered the CON, DGM, and EGM diets, ate 95, 98, and 96%, respectively, of the DM offered. The mean milk yield of cows fed the EGM diet was 12.8kg/cow per day and was less than that of cows fed either the CON diet (14.6kg/cow per day) or the DGM diet (15.4kg/cow per day). Feeding DGM and EGM diets was associated with decreased milk fat yields, lower concentrations of saturated fatty acids, and enhanced concentrations of mono- and polyunsaturated fatty acids, in particular cis-9,trans-11 linoleic acid. The mean CH4 emissions were 470, 375, and 389g of CH4/cow per day for cows fed the CON, DGM, and EGM diets, respectively. Methane yields were 26.1, 20.2, and 21.5g of CH4/kg of DMI for cows fed the CON, DGM, and EGM diets, respectively. The ruminal bacterial and archaeal communities were altered by dietary supplementation with grape marc, but ruminal fungal and protozoan communities were not. Decreases of approximately 20% in CH4 emissions and CH4 yield indicate that feeding DGM and EGM could play a role in CH4 abatement. PMID:24952778

Moate, P J; Williams, S R O; Torok, V A; Hannah, M C; Ribaux, B E; Tavendale, M H; Eckard, R J; Jacobs, J L; Auldist, M J; Wales, W J

2014-08-01

256

Field emission from carbon nanotubes in DC and pulsed mode  

NASA Astrophysics Data System (ADS)

Multi-wall Carbon Nanotube (CNT) emitters were tested in a combined diode-RF electron gun. Field emission of the nanotubes was observed at 5-30 MV/m, using a 250 ns FWHM long pulse with a peak voltage of 80-470 kV. The field emission threshold is compatible with that found from previous DC testing. We have extracted from a continuous field emitter up to a nanoCoulomb of charge and measured an emittance of 4 mm mrad with a 2 pC electron beam. The total charge emission during RF operation, using the 1.5 GHz, 2 cell RF structure, was found dependent on its period. RF operation showed that back bombarding electrons with up to 5 MeV did not impair the emission stability of the CNTs.

Le Pimpec, F.; Gough, C.; Chouhan, V.; Kato, S.

2011-12-01

257

A technology-based global inventory of black and organic carbon emissions from combustion  

Microsoft Academic Search

We present a global tabulation of black carbon (BC) and primary organic carbon (OC) particles emitted from combustion. We include emissions from fossil fuels, biofuels, open biomass burning, and burning of urban waste. Previous bottom-up inventories of black and organic carbon have assigned emission factors on the basis of fuel type and economic sector alone. Because emission rates are highly

Tami C. Bond; David G. Streets; Kristen F. Yarber; Sibyl M. Nelson; Jung-Hun Woo; Zbigniew Klimont

2004-01-01

258

A technology-based global inventory of black and organic carbon emissions from combustion  

Microsoft Academic Search

We present a global tabulation of black carbon (BC) and primary organic carbon (OC) particles emitted from combustion. We include emissions from fossil fuels, biofuels, open biomass burning, and burning of urban waste. Previous ``bottom-up'' inventories of black and organic carbon have assigned emission factors on the basis of fuel type and economic sector alone. Because emission rates are highly

Tami C. Bond; David G. Streets; Kristen F. Yarber; Sibyl M. Nelson; Jung-Hun Woo; Zbigniew Klimont

2004-01-01

259

40 CFR Table U-1 to Subpart U of... - CO2 Emission Factors for Common Carbonates  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false CO2 Emission Factors for Common Carbonates... Table U-1 to Subpart U of Part 98CO2 Emission Factors for Common Carbonates Mineral namecarbonate CO2 emission factor(tons CO2 /ton...

2011-07-01

260

Just Say No to Carbon Emissions (LBNL Science at the Theater)  

SciTech Connect

Learn about three efforts our grandchildren may thank us for: cheap solar energy, bringing energy efficiency to China, and learning how to store carbon deep underground. Can solar energy be dirt cheap? We're all potentially billionaires when it comes to solar energy. The trick is learning how to convert sunlight to electricity using cheap and plentiful materials. Ramamoorthy Ramesh, an innovative materials scientist at Berkeley Lab, will discuss how he and other researchers are working to make photovoltaic cells using the most abundant elements in the Earth's crust -- materials that are literally as common as dirt. Energy efficiency in China: Nan Zhou is a researcher with Berkeley Labs China Energy Group. She will speak about Chinas energy use and the policies that have been implemented to increase energy efficiency and reduce CO2 emission growth. Her work focuses on building China's capacity to evaluate, adopt and implement low-carbon development strategies. Zhou has an architecture degree from China, and a Master and Ph.D. in Engineering from Japan. Understanding geologic carbon sequestration: Even with continued growth of renewable energy sources such as wind and solar, fossil fuels will likely remain cheap and plentiful for decades to come. Geologist Curt Oldenburg, who heads Berkeley Lab's Geologic Carbon Sequestration Program, will discuss a strategy to reduce carbon emissions from coal and natural gas. It involves pumping compressed CO2 captured from large stationary sources into underground rock formations that can store it for geological time scales.

Ramesh, Ramamoorthy; Zhou, Nan; Oldenburg, Curt

2010-04-26

261

Just Say No to Carbon Emissions (LBNL Science at the Theater)  

ScienceCinema

Learn about three efforts our grandchildren may thank us for: cheap solar energy, bringing energy efficiency to China, and learning how to store carbon deep underground. Can solar energy be dirt cheap? We're all potentially billionaires when it comes to solar energy. The trick is learning how to convert sunlight to electricity using cheap and plentiful materials. Ramamoorthy Ramesh, an innovative materials scientist at Berkeley Lab, will discuss how he and other researchers are working to make photovoltaic cells using the most abundant elements in the Earth's crust -- materials that are literally as common as dirt. Energy efficiency in China: Nan Zhou is a researcher with Berkeley Labs China Energy Group. She will speak about Chinas energy use and the policies that have been implemented to increase energy efficiency and reduce CO2 emission growth. Her work focuses on building China's capacity to evaluate, adopt and implement low-carbon development strategies. Zhou has an architecture degree from China, and a Master and Ph.D. in Engineering from Japan. Understanding geologic carbon sequestration: Even with continued growth of renewable energy sources such as wind and solar, fossil fuels will likely remain cheap and plentiful for decades to come. Geologist Curt Oldenburg, who heads Berkeley Lab's Geologic Carbon Sequestration Program, will discuss a strategy to reduce carbon emissions from coal and natural gas. It involves pumping compressed CO2 captured from large stationary sources into underground rock formations that can store it for geological time scales.

Ramesh, Ramamoorthy; Zhou, Nan; Oldenburg, Curt

2011-04-28

262

Sunlight-induced carbon dioxide emissions from inland waters  

NASA Astrophysics Data System (ADS)

emissions of carbon dioxide (CO2) from inland waters are substantial on a global scale. Yet the fundamental question remains open which proportion of these CO2 emissions is induced by sunlight via photochemical mineralization of dissolved organic carbon (DOC), rather than by microbial respiration during DOC decomposition. Also, it is unknown on larger spatial and temporal scales how photochemical mineralization compares to other C fluxes in the inland water C cycle. We combined field and laboratory data with atmospheric radiative transfer modeling to parameterize a photochemical rate model for each day of the year 2009, for 1086 lakes situated between latitudes from 55N to 69N in Sweden. The sunlight-induced production of dissolved inorganic carbon (DIC) averaged 3.8 0.04 g C m-2 yr-1, which is a flux comparable in size to the organic carbon burial in the lake sediments. Countrywide, 151 1 kt C yr-1 was produced by photochemical mineralization, corresponding to about 12% of total annual mean CO2 emissions from Swedish lakes. With a median depth of 3.2 m, the lakes were generally deep enough that incoming, photochemically active photons were absorbed in the water column. This resulted in a linear positive relationship between DIC photoproduction and the incoming photon flux, which corresponds to the absorbed photons. Therefore, the slope of the regression line represents the wavelength- and depth-integrated apparent quantum yield of DIC photoproduction. We used this relationship to obtain a first estimate of DIC photoproduction in lakes and reservoirs worldwide. Global DIC photoproduction amounted to 13 and 35 Mt C yr-1 under overcast and clear sky, respectively. Consequently, these directly sunlight-induced CO2 emissions contribute up to about one tenth to the global CO2 emissions from lakes and reservoirs, corroborating that microbial respiration contributes a substantially larger share than formerly thought, and generate annual C fluxes similar in magnitude to the C burial in natural lake sediments worldwide.

Koehler, Birgit; Landelius, Tomas; Weyhenmeyer, Gesa A.; Machida, Nanako; Tranvik, Lars J.

2014-07-01

263

Energy, Carbon-emission and Financial Savings from Thermostat Control  

SciTech Connect

Among the easiest approaches to energy, and cost, savings for most people is the adjustment of thermostats to save energy. Here we estimate savings of energy, carbon, and money in the United States of America (USA) that would result from adjusting thermostats in residential and commercial buildings by about half a degree Celsius downward during the heating season and upward during the cooling season. To obtain as small a unit as possible, and therefore the least likely to be noticeable by most people, we selected an adjustment of one degree Fahrenheit (0.56 degree Celsius) which is the gradation used almost exclusively on thermostats in the USA and is the smallest unit of temperature that has been used historically. Heating and/or cooling of interior building space for personal comfort is sometimes referred to as space conditioning, a term we will use for convenience throughout this work without consideration of humidity. Thermostat adjustment, as we use the term here, applies to thermostats that control the indoor temperature, and not to other thermostats such as those on water heaters. We track emissions of carbon only, rather than of carbon dioxide, because carbon atoms change atomic partners as they move through the carbon cycle, from atmosphere to biosphere or ocean and, on longer time scales, through the rock cycle. To convert a mass of carbon to an equivalent mass of carbon dioxide (thereby including the mass of the 2 oxygen atoms in each molecule) simply multiply by 3.67.

Blasing, T J [ORNL; Schroeder, Dana [University of Georgia, Athens, GA

2013-08-01

264

Light Emission from Carbon Nanotube Field Effect Transistors  

NASA Astrophysics Data System (ADS)

Since their discovery in 1991, research in carbon nanotubes has grown rapidly. Part of this interest is driven by the remarkable electrical and mechanical properties demonstrated by carbon nanotubes which could have significant technological impact (1,2). Recent progress has included demonstrations of interesting opto-electronic properties of carbon nanotubes. In one experiment we have shown that single carbon nanotubes can be a source of infrared optical emission (3). We have also shown how a single carbon nanotube can be used as a photoconductive detector (4). In this talk, we will examine the opto-electronic properties of individual single wall carbon nanotubes. (1) M.S. Dresselhaus, G. Dresselhaus, and Ph. Avouris (eds.), "Carbon Nanotubes", Topics Appl. Phys. 80, (2001). (2) Ph. Avouris, Acct. Chem. Res. 35, 1026 (2002). (3) J.A. Misewich, R. Martel, Ph. Avouris, J. Tsang, S. Heinze, and J. Tersoff, Science 300, 783 (2003). (4) M. Freitag, Y. Martin, J.A. Misewich, R. Martel, and Ph. Avouris, Nanoletters 3, 1067 (2003).

Misewich, James

2004-03-01

265

Attributing land-use change carbon emissions to exported biomass  

SciTech Connect

In this study, a simple, transparent and robust method is developed in which land-use change (LUC) emissions are retrospectively attributed to exported biomass products based on the agricultural area occupied for the production. LUC emissions account for approximately one-fifth of current greenhouse gas emissions. Increasing agricultural exports are becoming an important driver of deforestation. Brazil and Indonesia are used as case studies due to their significant deforestation in recent years. According to our study, in 2007, approximately 32% and 15% of the total agricultural land harvested and LUC emissions in Brazil and Indonesia respectively were due to exports. The most important exported single items with regard to deforestation were palm oil for Indonesia and bovine meat for Brazil. To reduce greenhouse gas (GHG) emissions effectively worldwide, leakage of emissions should be avoided. This can be done, for example, by attributing embodied LUC emissions to exported biomass products. With the approach developed in this study, controversial attribution between direct and indirect LUC and amortization of emissions over the product life cycle can be overcome, as the method operates on an average basis and annual level. The approach could be considered in the context of the UNFCCC climate policy instead of, or alongside with, other instruments aimed at reducing deforestation. However, the quality of the data should be improved and some methodological issues, such as the allocation procedure in multiproduct systems and the possible dilution effect through third parties not committed to emission reduction targets, should be considered. - Highlights: Black-Right-Pointing-Pointer CO{sub 2} emissions from land use changes are highly important. Black-Right-Pointing-Pointer Attribution of land use changes for products is difficult. Black-Right-Pointing-Pointer Simple and robust method is developed to attribute land use change emissions.

Saikku, Laura, E-mail: laura.saikku@helsinki.fi [University of Helsinki, P.O Box 65, 00014 University of Helsinki (Finland); Soimakallio, Sampo, E-mail: sampo.soimakallio@vtt.fi [VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 VTT (Finland); Pingoud, Kim, E-mail: kim.pingoud@vtt.fi [VTT Technical Research Centre of Finland, P.O. Box 1000, 02044 VTT (Finland)

2012-11-15

266

Electron Field Emission of Silicon-Doped Diamond-Like Carbon Thin Films  

NASA Astrophysics Data System (ADS)

In this work we demonstrate that the field emission characteristics of disordered Si-doped diamond-like carbon (DLC) thin films depend not only on properties of the conductive clustered sp2 phase and the insulating sp3 matrix (or sp2/sp3 ratio) but also on the presence of Si-Hn and C-Hn species in the film. The presence of such species reduces the hardness of the film and simultaneously enhances the field emission performance. A turn on electric field (ETOF) of 6.76 V/m produced a field emission current density of 0.2 mA/cm2, when an electric field of 20 V/m was applied. The Fowler-Nordheim (FN) tunneling model is appropriate to explain the field emission mechanism only within limited range of the current density. However, it is found that there is an apparent crossover between space charge limited current (SCLC) and the Frenkel effect due to impurities incorporated during the fabrication of Si-DLC films. This combined effect (SCLC + Frenkel) allows for the emission of electrons from the top of the reduced barriers due to the formation of comparatively soft DLC:Si films. The emission also occurs through tunneling from one conductive cluster (sp2 C=C) to another separated by an insulating matrix (sp3 C-C) after reducing the effective depth of a trap on application of high electric field.

Ray, Sekhar Chandra; Ghosh, Sarit Kumar; Chiguvare, Zivayi; Palnitkar, Umesh; Pong, Way-Faung; Lin, I.-Nan; Papakonstantinou, Pagona; Strydom, Andr Michael

2010-11-01

267

Carbon dioxide and methane emissions from the Yukon River system  

NASA Astrophysics Data System (ADS)

Carbon dioxide (CO2) and methane (CH4) emissions are important, but poorly quantified, components of riverine carbon (C) budgets. This is largely because the data needed for gas flux calculations are sparse and are spatially and temporally variable. Additionally, the importance of C gas emissions relative to lateral C exports is not well known because gaseous and aqueous fluxes are not commonly measured on the same rivers. We couple measurements of aqueous CO2 and CH4 partial pressures (pCO2, pCH4) and flux across the water-air interface with gas transfer models to calculate subbasin distributions of gas flux density. We then combine those flux densities with remote and direct observations of stream and river water surface area and ice duration, to calculate C gas emissions from flowing waters throughout the Yukon River basin. CO2 emissions were 7.68 Tg C yr-1 (95% CI: 5.84 -10.46), averaging 750 g C m-2 yr-1 normalized to water surface area, and 9.0 g C m-2 yr-1 normalized to river basin area. River CH4 emissions totaled 55 Gg C yr-1 or 0.7% of the total mass of C emitted as CO2 plus CH4 and 6.4% of their combined radiative forcing. When combined with lateral inorganic plus organic C exports to below head of tide, C gas emissions comprised 50% of total C exported by the Yukon River and its tributaries. River CO2 and CH4 derive from multiple sources, including groundwater, surface water runoff, carbonate equilibrium reactions, and benthic and water column microbial processing of organic C. The exact role of each of these processes is not yet quantified in the overall river C budget.

Striegl, Robert G.; Dornblaser, M. M.; McDonald, C. P.; Rover, J. R.; Stets, E. G.

2012-12-01

268

Trend in global black carbon emissions from 1960 to 2007.  

PubMed

Black carbon (BC) plays an important role in both climate change and health impact. Still, BC emissions as well as the historical trends are associated with high uncertainties in existing inventories. In the present study, global BC emissions from 1960 to 2007 were estimated for 64 sources, by using recompiled fuel consumption and emission factor data sets. Annual BC emissions had increased from 5.3 (3.4-8.5 as an interquartile range) to 9.1 (5.6-14.4) teragrams during this period. Our estimations are 11-16% higher than those in previous inventories. Over the period, we found that the BC emission intensity, defined as the amount of BC emitted per unit of energy production, had decreased for all the regions, especially China and India. Improvements in combustion technology and changes in fuel composition had led to an increase in energy use efficiency, and subsequently a decline of BC emission intensities in power plants, the residential sector, and transportation. On the other hand, the BC emission intensities had increased in the industrial and agricultural sectors, mainly due to an expansion of low-efficiency industry (coke and brick production) in developing countries and to an increasing usage of diesel in agriculture in developed countries. PMID:24825392

Wang, Rong; Tao, Shu; Shen, Huizhong; Huang, Ye; Chen, Han; Balkanski, Yves; Boucher, Olivier; Ciais, Philippe; Shen, Guofeng; Li, Wei; Zhang, Yanyan; Chen, Yuanchen; Lin, Nan; Su, Shu; Li, Bengang; Liu, Junfeng; Liu, Wenxin

2014-06-17

269

Global carbon dioxide emission to the atmosphere by volcanoes  

SciTech Connect

Global emission of carbon dioxide by subaerial volcanoes is calculated, using CO{sub 2}/SO{sub 2} from volcanic gas analyses and SO{sub 2} flux, to be 34 {plus minus} 24 {times} 10{sup 12} g CO{sub 2}/yr from passive degassing and 31 {plus minus} 22 {times} 10{sup 12} g CO{sub 2}/yr from eruptions. Volcanic CO{sub 2} presently represents only 0.22% of anthropogenic emissions but may have contributed to significant greenhouse' effects at times in Earth history. Models of climate response to CO{sub 2} increases may be tested against geological data.

Williams, S.N.; Schaefer, S.J. (Arizona State Univ., Tempe (United States)); Calvache V., M.L. (Arizona State Univ., Tempe (United States) Observatorio Vulcanologico de Colombia, Pasto (Colombia)); Lopez, D. (Univ. of British Columbia, Vancouver (Canada))

1992-04-01

270

Carbon emissions performance of commercial logging in East Kalimantan, Indonesia.  

PubMed

Adoption of reduced-impact logging (RIL) methods could reduce CO2 emissions by 30-50% across at least 20% of remaining tropical forests. We developed two cost effective and robust indices for comparing the climate benefits (reduced CO2 emissions) due to RIL. The indices correct for variability in the volume of commercial timber among concessions. We determined that a correction for variability in terrain slope was not needed. We found that concessions certified by the Forest Stewardship Council (FSC, N=3), when compared with noncertified concessions (N=6), did not have lower overall CO2 emissions from logging activity (felling, skidding, and hauling). On the other hand, FSC certified concessions did have lower emissions from one type of logging impact (skidding), and we found evidence of a range of improved practices using other field metrics. One explanation of these results may be that FSC criteria and indicators, and associated RIL practices, were not designed to achieve overall emissions reductions. Also, commonly used field metrics are not reliable proxies for overall logging emissions performance. Furthermore, the simple distinction between certified and noncertified concessions does not fully represent the complex history of investments in improved logging practices. To clarify the relationship between RIL and emissions reductions, we propose the more explicit term 'RIL-C' to refer to the subset of RIL practices that can be defined by quantified thresholds and that result in measurable emissions reductions. If tropical forest certification is to be linked with CO2 emissions reductions, certification standards need to explicitly require RIL-C practices. PMID:24022913

Griscom, Bronson; Ellis, Peter; Putz, Francis E

2014-03-01

271

Reducing health care's carbon footprint--the power of nursing.  

PubMed

Global warming and environmentalism continue to be national and international issues as their complexities and implications become better understood. One ironic contributor to the degradation of the environment is the health care system. Serving as clinical laboratories, hotels, restaurants, and offices that never close, U.S. hospitals produce more than 2 million tons of waste annually. Although the consequences and significance of health care's carbon footprint are undeniable, strategies to reduce this impact are challenging. This article discusses how the role, traits, and knowledge of nurses combined with their positions in the health care system make them key players in creating an environmentally sustainable health care industry. With an analysis of environmental action versus inaction, this article explores how nurses at the forefront of health care are equipped to change practice that will reach far beyond the bedside. PMID:23413481

Muoz, Aliria

2012-11-01

272

European community can reduce CO{sub 2} emissions by sixty percent: A feasibility study  

SciTech Connect

Carbon dioxide (CO{sub 2}) emissions in the European Community (EC) can be reduced by roughly 60 percent. A great many measures need to be taken to reach this reduction, with a total annual cost of ECU 55 milliard. Fossil fuel use is the main cause of CO{sub 2} emissions into the atmosphere; CO{sub 2} emissions are to a large extent responsible for the greenhouse effect. Energy saving (conservation) and nuclear energy appear to be the least expensive methods of CO{sub 2} abatement, directly followed by renewables. More expensive alternatives include the separation of CO{sub 2} at the source (e.g., power plants), followed by storage in depleted gas fields, aquifers, or in the ocean. Biological options, such as reforestation and energy farming, are the most expensive abatement methods; however, they do have secondary advantages, such as avoided fallow premiums and avoided export premiums on cereals. Application of all measures together can lead to the 60 percent reduction goal. 11 refs., 5 figs., 1 tab.

Mot, E.; Baar, H.J.W. de [Netherlands Institute for Oceanic Sciences, Apeldoorn (Netherlands)

1993-06-01

273

Chemical and stable carbon isotopic composition of PM2.5 from on-road vehicle emissions in the PRD region and implication for vehicle emission control policy  

NASA Astrophysics Data System (ADS)

Vehicle emission is a major source of urban air pollution. In recent decade, the Chinese government has introduced a range of policies to reduce the vehicle emission. In order to understand the chemical characteristics of PM2.5 from on-road vehicle emission in the Pearl River Delta (PRD) region and to evaluate the effectiveness of control policies on vehicles emission, the emission factors of PM2.5 mass, elemental carbon (EC), organic carbon (OC), water-soluble organic carbon (WSOC), water-soluble inorganic ions (WSII), metal elements, organic compounds and stable carbon isotopic composition were measured in the Zhujiang Tunnel of Guangzhou, the PRD region of China in 2013. Emission factors of PM2.5 mass, OC, EC, and WSOC were 92.4, 16.7, 16.4, and 1.31 mg vehicle-1 km-1 respectively. Emission factors of WSII were 0.016 (F-) ~4.17 (Cl-) mg vehicle-1 km-1, totally contributing about 9.8% to the PM2.5 emissions. The sum of 27 measured metal elements accounted for 15.2% of the PM2.5 emissions. Fe was the most abundant metal element, with an emission factor of 3.91 mg vehicle-1 km-1. Emission factors of organic compounds including n-alkanes, PAHs, hopanes, and steranes were 91.9, 5.02, 32.0 and 7.59 ?g vehicle-1 km-1, respectively. Stable carbon isotopic composition ?13C value was measured and it was -25.0 on average. An isotopic fractionation of 3.2 was found during fuel combustion. Compared with a previous study in Zhujiang Tunnel in year 2004, emission factors of PM2.5 mass, EC, OC, WSII except Cl-, and organic compounds decreased by 16.0-93.4%, which could be attributed to emission control policy from 2004 to 2013. However, emission factors of most of the metal elements increased significantly, which could be partially attributed to the changes in motor oil additives and vehicle condition. There are no mandatory national standards to limit metal content from vehicle emission, which should be a concern of the government. A snapshot of the 2013 characteristic emission of PM2.5 and its constituents from on-road vehicular fleet in the PRD region retrieved from our study was found to be useful for the assessment of past and future implementation of vehicle emission control policy.

Dai, S.; Bi, X.; Chan, L. Y.; He, J.; Wang, B.; Wang, X.; Sheng, G.; Fu, J.

2014-11-01

274

MANAGEMENT OPTIONS FOR REDUCING AMMONIA EMISSIONS FROM POULTRY LITTER  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ammonia emissions from poultry litter not only result in air pollution; high levels of ammonia in poultry houses cause poor bird performance, increase the susceptibility of birds to viral diseases, and negatively impact human health. Although ammonia emissions are a concern, few cost-effective best ...

275

Management Options for Reducing Ammonia Emissions from Poultry Litter  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ammonia emissions from poultry litter not only result in air pollution; high levels of ammonia in poultry houses cause poor bird performance, increase the susceptibility of birds to viral diseases, and negatively impact human health. Although ammonia emissions are a concern, few cost-effective best ...

276

Control of variable geometry turbocharged diesel engines for reduced emissions  

Microsoft Academic Search

The emission control problem for an automotive direct injected compression ignition (diesel) engine equipped with exhaust gas recirculation (EGR) and a variable geometry turbocharger (VGT) is considered. The objective is to operate the engine to meet driver's torque demand and minimize NOx emissions while at the same time avoiding visible smoke generation. It is demonstrated that the steady-state optimization of

Anna G. Stefanopoulou; Ilya Kolmanovsky; James S. Freudenberg

2000-01-01

277

Renewable energy for low carbon emission IP over WDM networks  

Microsoft Academic Search

In this paper we propose a low-carbon emission IP over WDM network where renewable energy is used to replace some of the non-renewable energy sources. We develop a Linear Programming (LP) model with the objective of minimizing the non-renewable energy consumption and propose a novel heuristic for improving renewable energy utilization. Compared with routing in the electronic layer, the results

Xiaowen Dong; Taisir El-Gorashi; Jaafar M. H. Elmirghani

2011-01-01

278

Warming Reduces Carbon Losses from Grassland Exposed to Elevated Atmospheric Carbon Dioxide  

PubMed Central

The flux of carbon dioxide (CO2) between terrestrial ecosystems and the atmosphere may ameliorate or exacerbate climate change, depending on the relative responses of ecosystem photosynthesis and respiration to warming temperatures, rising atmospheric CO2, and altered precipitation. The combined effect of these global change factors is especially uncertain because of their potential for interactions and indirectly mediated conditions such as soil moisture. Here, we present observations of CO2 fluxes from a multi-factor experiment in semi-arid grassland that suggests a potentially strong climate carbon cycle feedback under combined elevated [CO2] and warming. Elevated [CO2] alone, and in combination with warming, enhanced ecosystem respiration to a greater extent than photosynthesis, resulting in net C loss over four years. The effect of warming was to reduce respiration especially during years of below-average precipitation, by partially offsetting the effect of elevated [CO2] on soil moisture and C cycling. Carbon losses were explained partly by stimulated decomposition of soil organic matter with elevated [CO2]. The climate carbon cycle feedback observed in this semiarid grassland was mediated by soil water content, which was reduced by warming and increased by elevated [CO2]. Ecosystem models should incorporate direct and indirect effects of climate change on soil water content in order to accurately predict terrestrial feedbacks and long-term storage of C in soil. PMID:23977180

Pendall, Elise; Heisler-White, Jana L.; Williams, David G.; Dijkstra, Feike A.; Carrillo, Yolima; Morgan, Jack A.; LeCain, Daniel R.

2013-01-01

279

Net Productivity and Reduced Carbon Flux at Different Timescales at a Subarctic Mire  

NASA Astrophysics Data System (ADS)

While several environmental changes that appear linked to increased temperature and permafrost degradation have been noted in the panarctic, the concern is to what extent positive feedback mechanisms that may accelerate climate change are associated with these environmental and physical changes. Labile organic carbon, currently protected in frozen soils, may mobilize if soils are warmed and thawed and then transferred to the atmosphere as greenhouse gases. Detailed information about carbon cycling in perennially frozen carbon rich soils needs to be incorporated into coupled climate models. In this study, we account for the productivity and reduced carbon flux at the subarctic Stordalen Mire in northern Sweden. Methane (CH4) and total hydrocarbon (THC; CH4 and nonmethane hydrocarbons) fluxes were measured at three vegetation communities with different moisture and permafrost regimes; i) a dry palsa site underlain with permafrost, ii) a Sphagnum site with highly variable water table and iii) a wet Eriophorum site. The two latter sites are CH4 emitting environments. A long-term data record of five sequential growing seasons (2003-2007) acquired with an automatic chamber system allows for analyses at least three levels of temporal variability (diurnal, seasonal and annual). There was a clear relation between seasonal accumulated THC emissions and productivity (measured as NEE of CO2), when all vegetation communities were compared in the same analysis. At the Sphagnum site, ~2 gC m-2 was emitted as THC at the same time as ~40 gC m-2 was taken up as CO2, (days 173- 235, year 2003-2006). In comparison, a highly productive Eriophorum sp. community emitted ~9 gC m-2 (THC) while productivity was estimated to ~90 gC m-2 (CO2). Productivity differences between sites can be a measure of the THC emission potential, but the seasonal accumulated THC emissions within a site appeared to be largely independent of seasonal productivity at the same site. Short-term (hourly) NEE was related to hydrocarbon emission at the two CH4 emitting sites. A greater part of the carbon emitted as THC is likely to recently have been sequestered by the plants through photosynthesis and plant mediated CH4 transport during high CO2 metabolism will strengthen the short-term correlation between THC and CO2.

Bckstrand, K.; Crill, P. M.; Christensen, T. R.; Mastepanov, M.; Bastviken, D.

2007-12-01

280

Carbon bed mercury emissions control for mixed waste treatment.  

PubMed

Mercury has various uses in nuclear fuel reprocessing and other nuclear processes, and so it is often present in radioactive and mixed (radioactive and hazardous) wastes. Compliance with air emission regulations such as the Hazardous Waste Combustor (HWC) Maximum Achievable Control Technology (MACT) standards can require off-gas mercury removal efficiencies up to 99.999% for thermally treating some mixed waste streams. Test programs have demonstrated this level of off-gas mercury control using fixed beds of granular sulfur-impregnated activated carbon. Other results of these tests include (1) the depth of the mercury control mass transfer zone was less than 15-30 cm for the operating conditions of these tests; (2) MERSORB carbon can sorb mercury up to 19 wt % of the carbon mass; and (3) the spent carbon retained almost all (98.3-99.99%) of the mercury during Toxicity Characteristic Leachability Procedure (TCLP) tests, but when even a small fraction of the total mercury dissolves, the spent carbon can fail the TCLP test when the spent carbon contains high mercury concentrations. PMID:21141428

Soelberg, Nick; Enneking, Joe

2010-11-01

281

Carbon offset accounting and monitoring of emission reductions in energy efficiency projects  

SciTech Connect

The UN Framework Convention on Climate Change (FCCC) allows for the joint implementation (JI) of measures to mitigate the emissions of greenhouse gases. The concept of JI refers to the implementation of such measures in one country with partial or full financial and/or technical support from another country, potentially fulfilling some of the supporting country's emission-reduction commitment under the FCCC. JI projects in developing countries without reduction obligations require a carbon-offset mechanism, under which emitters can receive credit toward their country's reduction commitment for investments to reduce CO{sub 2} emissions in other countries. Energy efficiency projects offer some of the most attractive opportunities for JI projects. Because energy efficiency measures are generally close to commercial viability, they offer the prospect of relatively low-cost carbon offsets. The technical efficiency potential in developing countries is large and offers benefits in terms of technology transfer and pollution prevention. Carbon offsets under a JI regime could become a major source of funding for energy efficiency in developing countries. This paper addresses key issues related to JI under the FCCC as they relate to the development of energy efficiency projects for carbon offsets in developing countries. Issues include the reference case or baselines, carbon accounting and net carbon savings, monitoring and verification, local agreements and host-country approval. Although the technical issues regarding carbon accounting and monitoring/verification are often treated as barriers to establishing a JI process, the authors demonstrate that these problems are soluble at reasonable cost using available technologies and methods.

Swisher, J.N.

1998-07-01

282

Spontaneous emission from the C3 radical in carbon plasma.  

PubMed

Spontaneous emission measurements are discussed for the Swings transitions of the C(3) radical in laser-generated graphite plasma, and the spectroscopy of the C(3) radical in carbon vapor and plasma is summarized. A review is given of some theoretical calculations and emission spectroscopic investigations are presented. Time-averaged, laser-induced optical breakdown spectra are reported from Nd:YAG laser generated graphite microplasma. In 200-300 Torr of argon and helium, and depending on the specific experimental configuration, a weak emission continuum is observed centered at 400 nm when using a laser fluence of typically 1 J/cm(2). Such continua were not detected in our previous experiments using focused laser radiation. The possibilities for the origin of this continuum are considered. PMID:17571143

Nemes, Lszl; Keszler, Anna M; Parigger, Christian G; Hornkohl, James O; Michelsen, Hope A; Stakhursky, Vadim

2007-07-01

283

GreenColo: Incentivizing Tenants for Reducing Carbon Footprint in Colocation Data Centers  

E-print Network

1 GreenColo: Incentivizing Tenants for Reducing Carbon Footprint in Colocation Data Centers energy consumption of data centers worldwide has resulted in a large carbon footprint, raising serious their servers for carbon efficiency. In this paper, we aim at minimizing the carbon footprint of geo

Ren, Shaolei

284

Emission reduction of NOx, PM, PM-carbon, and PAHs from a generator fuelled by biodieselhols.  

PubMed

This investigation examines the particulate matter (PM), particulate carbon, polycyclic aromatic hydrocarbons (PAHs), and nitrogen oxides (NOx) emitted from a generator fueled by petroleum diesel blended with waste-edible-oil-biodiesel and water-containing acetone. Experimental results show that using biodieselhols with water-containing (or pure) acetone as the fuel of generator, in comparison to using petroleum diesel, significantly reduces PM emission; roughly, this reduction increased as percentage of water-containing acetone increased. When the percentages of waste-edible-oil-biodiesel were ? 5 vol%, adding pure or water-containing acetone (1-3 vol%) to biodieselhols generated emission reductions of NOx, PM, particle-bound organic carbon (OC), total-PAHs, and total-BaPeq. Consequently, using water-containing acetone biodieselhols as an alternative generator fuel is feasible and helps recycle and reuse waste solvents containing water-containing acetone. PMID:24797907

Tsai, Jen-Hsiung; Chen, Shui-Jen; Huang, Kuo-Lin; Lin, Wen-Yinn; Lee, Wen-Jhy; Chao, How-Ran; Lin, Chih-Chung; Hsieh, Lien-Te

2014-06-15

285

Potential climate engineering effectiveness and side effects during a high carbon dioxide-emission scenario.  

PubMed

The realization that mitigation efforts to reduce carbon dioxide emissions have, until now, been relatively ineffective has led to an increasing interest in climate engineering as a possible means of preventing the potentially catastrophic consequences of climate change. While many studies have addressed the potential effectiveness of individual methods there have been few attempts to compare them. Here we use an Earth system model to compare the effectiveness and side effects of afforestation, artificial ocean upwelling, ocean iron fertilization, ocean alkalinization and solar radiation management during a high carbon dioxide-emission scenario. We find that even when applied continuously and at scales as large as currently deemed possible, all methods are, individually, either relatively ineffective with limited (<8%) warming reductions, or they have potentially severe side effects and cannot be stopped without causing rapid climate change. Our simulations suggest that the potential for these types of climate engineering to make up for failed mitigation may be very limited. PMID:24569320

Keller, David P; Feng, Ellias Y; Oschlies, Andreas

2014-01-01

286

Potential climate engineering effectiveness and side effects during a high carbon dioxide-emission scenario  

NASA Astrophysics Data System (ADS)

The realization that mitigation efforts to reduce carbon dioxide emissions have, until now, been relatively ineffective has led to an increasing interest in climate engineering as a possible means of preventing the potentially catastrophic consequences of climate change. While many studies have addressed the potential effectiveness of individual methods there have been few attempts to compare them. Here we use an Earth system model to compare the effectiveness and side effects of afforestation, artificial ocean upwelling, ocean iron fertilization, ocean alkalinization and solar radiation management during a high carbon dioxide-emission scenario. We find that even when applied continuously and at scales as large as currently deemed possible, all methods are, individually, either relatively ineffective with limited (<8%) warming reductions, or they have potentially severe side effects and cannot be stopped without causing rapid climate change. Our simulations suggest that the potential for these types of climate engineering to make up for failed mitigation may be very limited.

Keller, David P.; Feng, Ellias Y.; Oschlies, Andreas

2014-02-01

287

Multi-impact optimization to reduce aviation noise and emissions  

Microsoft Academic Search

This paper describes a multi-indicator assessment and minimization problem focused on aviation Community noise. The model explores a combined noise and emission objective for airfreight movements at Luxembourgs Findel Airport. Community noise is evaluated via four population impact indicators emissions are tabulated from in-flight segments in the proximity of the airport and from the contribution of taxiing. A set of

Daniel S. Zachary; Jessica Gervais; Ulrich Leopold

2010-01-01

288

Truck Stop Electrification as a Strategy To Reduce Greenhouse Gases, Fuel Consumption and Pollutant Emissions  

E-print Network

, and carbon dioxide (CO2) emissions by 2.1 tons. The paper provides both observed and modeled results periods of time that drivers spend resting and sleeping in the cabs of their trucks. As a consequence on a daily basis nationwide due to extended idling (1). In addition, about 140,000 tons of carbon dioxide (CO

289

Radiative Forcing associated with Particulate Carbon Emissions resulting from the Use of Mercury Control Technology  

NASA Astrophysics Data System (ADS)

Mercury is a persistent, toxic metal that bio-accumulates within the food web and causes neurological damage and fetal defects in humans. The U.S. was the first country to regulate the leading anthropogenic source of mercury into the atmosphere: coal combustion for electric power generation. The U.S. EPA's 2005 Clean Air Mercury Rule (CAMR) was replaced and further tightened in 2012 by the Mercury and Air Toxics Standard (MATS), which required existing coal-fired utilities to reduce their mercury emissions by approximately 90% by 2015. Outside the U.S., the Governing Council of the United Nations Environment Programme (UNEP) has passed the legally binding Minamata global mercury treaty that compels its signatory countries to prevent and reduce the emission and release of mercury. The most mature technology for controlling mercury emissions from coal combustion is the injection into the flue gas of powdered activated carbon (PAC) adsorbents having chemically treated surfaces designed to rapidly oxidize and adsorb mercury. However, such PAC is known to have electrical properties that make it difficult to remove from flue gas via electrostatic precipitation, by far the most common particulate control technology used in countries such as the U.S., India, and China which rely heavily on coal for power generation. As a result, PAC used to control mercury emissions can be emitted into the atmosphere, the sub-micron fraction of which may result in unintended radiative forcing similar to black carbon (BC). Here, we estimate the potential increases in secondary BC emissions, those not produced from combustion but arising instead from the use of injected PAC for mercury emission reduction. We also calculate the radiative forcing associated with these secondary BC emissions by using a global atmospheric chemical transport model coupled with a radiative transfer model.

Clack, H.; Penner, J. E.; Lin, G.

2013-12-01

290

A "carbonizing dragon": China's fast growing CO2 emissions revisited.  

PubMed

China's annual CO(2) emissions grew by around 4 billion tonnes between 1992 and 2007. More than 70% of this increase occurred between 2002 and 2007. While growing export demand contributed more than 50% to the CO(2) emission growth between 2002 and 2005, capital investments have been responsible for 61% of emission growth in China between 2005 and 2007. We use structural decomposition analysis to identify the drivers for China's emission growth between 1992 and 2007, with special focus on the period 2002 to 2007 when growth was most rapid. In contrast to previous analysis, we find that efficiency improvements have largely offset additional CO(2) emissions from increased final consumption between 2002 and 2007. The strong increases in emissions growth between 2002 and 2007 are instead explained by structural change in China's economy, which has newly emerged as the third major emission driver. This structural change is mainly the result of capital investments, in particular, the growing prominence of construction services and their carbon intensive supply chain. By closing the model for capital investment, we can now show that the majority of emissions embodied in capital investment are utilized for domestic household and government consumption (35-49% and 19-36%, respectively) with smaller amounts for the production of exports (21-31%). Urbanization and the associated changes in lifestyle are shown to be more important than other socio-demographic drivers like the decreasing household size or growing population. We argue that mitigation efforts will depend on the future development of these key drivers, particularly capital investments which dictate future mitigation costs. PMID:21888374

Minx, Jan C; Baiocchi, Giovanni; Peters, Glen P; Weber, Christopher L; Guan, Dabo; Hubacek, Klaus

2011-11-01

291

Reducing emissions from deforestation--The ``combined incentives'' mechanism and empirical simulations  

E-print Network

Reducing emissions from deforestation--The ``combined incentives'' mechanism and empirical throughout a century of climate-change (Gullison et al., 2007). The financial rationale for deforestation be sufficient to greatly reduce deforestation (Stern, 2007). For political and methodological reasons

Vermont, University of

292

Field emission from Mo2C coated carbon nanosheets  

NASA Astrophysics Data System (ADS)

Carbon nanosheets have recently evolved into useful edge emitters with high emission current densities, low threshold electric fields, and long lifetimes. In addition to further improvement in these characteristics, good stability and repeatability are also essential for these materials to be suitable for high vacuum applications such as microwave tubes and flat panel displays. Since the work function of graphite, carbon nanotubes, and amorphous carbon is relatively high, 4.6-4.8eV, selective thin film coatings may offer significant advantages. Carbides are a good film choice for their corrosive resistance, chemical stability, and substantially lower work function. Approximately 3 ML (monolayer) (1nm) of molybdenum were deposited on carbon nanosheets by physical vapor deposition and the carbide (Mo2C) formed by heating to >200C at 110-8Torr. The carbide stoichiometry was confirmed in situ by the characteristic Auger triple peak at 272eV. A stoichiometric Mo2C calibration sample was used to acquire the Auger electron spectroscopy asymmetric ratio of 0.7 and this was used to determine the carbide growth as a function of temperature (from room temperature to 1000C). Field emission currents of up to 400?A were compared with uncoated CNS at a given electric field. The Mo2C/CNS cathodes were shown to have greater than a factor of 100 increase in current and greater than 2V/?m decrease in threshold. The Fowler-Nordheim plots were exceptionally linear and quite repeatable (correlation coefficient R2=0.999+). Using the slope and vertical intercept, an emission area for the 0.07cm2 Mo2C/CNS dot sample was determined to be 310-9cm2 and the field enhancement factor was found to be ? 530.

Bagge-Hansen, M.; Outlaw, R. A.; Miraldo, P.; Zhu, M. Y.; Hou, K.; Theodore, N. D.; Zhao, X.; Manos, D. M.

2008-01-01

293

Historical carbon emissions and uptake from the agricultural frontier of the Brazilian Amazon.  

PubMed

Tropical ecosystems play a large and complex role in the global carbon cycle. Clearing of natural ecosystems for agriculture leads to large pulses of CO2 to the atmosphere from terrestrial biomass. Concurrently, the remaining intact ecosystems, especially tropical forests, may be sequestering a large amount of carbon from the atmosphere in response to global environmental changes including climate changes and an increase in atmospheric CO2. Here we use an approach that integrates census-based historical land use reconstructions, remote-sensing-based contemporary land use change analyses, and simulation modeling of terrestrial biogeochemistry to estimate the net carbon balance over the period 1901-2006 for the state of Mato Grosso, Brazil, which is one of the most rapidly changing agricultural frontiers in the world. By the end of this period, we estimate that of the state's 925 225 km2, 221 092 km2 have been converted to pastures and 89 533 km2 have been converted to croplands, with forest-to-pasture conversions being the dominant land use trajectory but with recent transitions to croplands increasing rapidly in the last decade. These conversions have led to a cumulative release of 4.8 Pg C to the atmosphere, with 80% from forest clearing and 20% from the clearing of cerrado. Over the same period, we estimate that the residual undisturbed ecosystems accumulated 0.3 Pg C in response to CO2 fertilization. Therefore, the net emissions of carbon from Mato Grosso over this period were 4.5 Pg C. Net carbon emissions from Mato Grosso since 2000 averaged 146 Tg C/yr, on the order of Brazil's fossil fuel emissions during this period. These emissions were associated with the expansion of croplands to grow soybeans. While alternative management regimes in croplands, including tillage, fertilization, and cropping patterns promote carbon storage in ecosystems, they remain a small portion of the net carbon balance for the region. This detailed accounting of a region's carbon balance is the type of foundation analysis needed by the new United Nations Collaborative Programmme for Reducing Emissions from Deforestation and Forest Degradation (REDD). PMID:21639042

Galford, Gillian L; Melillo, Jerry M; Kicklighter, David W; Mustard, John F; Cronin, Timothy W; Cerri, Carlos E P; Cerri, Carlos C

2011-04-01

294

Impact of inland shipping emissions on elemental carbon concentrations near waterways in The Netherlands  

NASA Astrophysics Data System (ADS)

This study aims to quantify the impact of black carbon from inland shipping on air quality, expressed as elemental carbon (EC) near inland waterways in The Netherlands. Downwind measurements of particle numbers and EC were used to establish emission factors for EC from inland shipping using inverse modelling. These emission factors were combined with data on energy consumption to derive annual average emissions rates for all Dutch waterways. A line source model was applied to compute the contribution of inland shipping to annual average EC concentrations for around 140,000 people living within 200 m of busy waterways in The Netherlands. The results showed that they are exposed to additional EC concentrations of up to 0.5 ?g EC per m3 depending on the shipping volume and distance from the waterway. In view of the envisaged growth in water transport, this underlines the need to reduce combustion emissions from inland shipping. Targeting gross polluters may be the most effective approach since 30% of ships cause more than 80% of the total emissions.

Keuken, M. P.; Moerman, M.; Jonkers, J.; Hulskotte, J.; Denier van der Gon, H. A. C.; Hoek, G.; Sokhi, R. S.

2014-10-01

295

Removal of floral microbiota reduces floral terpene emissions  

NASA Astrophysics Data System (ADS)

The emission of floral terpenes plays a key role in pollination in many plant species. We hypothesized that the floral phyllospheric microbiota could significantly influence these floral terpene emissions because microorganisms also produce and emit terpenes. We tested this hypothesis by analyzing the effect of removing the microbiota from flowers. We fumigated Sambucus nigra L. plants, including their flowers, with a combination of three broad-spectrum antibiotics and measured the floral emissions and tissular concentrations in both antibiotic-fumigated and non-fumigated plants. Floral terpene emissions decreased by ca. two thirds after fumigation. The concentration of terpenes in floral tissues did not decrease, and floral respiration rates did not change, indicating an absence of damage to the floral tissues. The suppression of the phyllospheric microbial communities also changed the composition and proportion of terpenes in the volatile blend. One week after fumigation, the flowers were not emitting ?-ocimene, linalool, epoxylinalool, and linalool oxide. These results show a key role of the floral phyllospheric microbiota in the quantity and quality of floral terpene emissions and therefore a possible key role in pollination.

Peuelas, Josep; Farr-Armengol, Gerard; Llusia, Joan; Gargallo-Garriga, Albert; Rico, Laura; Sardans, Jordi; Terradas, Jaume; Filella, Iolanda

2014-10-01

296

Reduced Carbon Solubility in Fe Nanoclusters and Implications for the Growth of Single-Walled Carbon Nanotubes  

E-print Network

Reduced Carbon Solubility in Fe Nanoclusters and Implications for the Growth of Single of the minimum temperature necessary for the growth. We address this phenomenon in terms of solubility of C in Fe of single-walled carbon nanotubes, corresponding to unaffected, reduced, and no solubility of C

Curtarolo, Stefano

297

Carbon nanotube based field emission X-ray sources  

NASA Astrophysics Data System (ADS)

This dissertation describes the development of field emission (FE) x-ray sources with a carbon-nanotube (CNT) cathode. Field emission x-rays have advantages over conventional x-rays by replacing the thermionic cathode with a cold cathode so that electrons are emitted at room temperature and emission is voltage controllable. CNTs are found to be excellent electron emitters with low threshold fields and high current density which makes them ideal for generate field emission x-rays. Macroscopic CNT cold cathodes are prepared and the parameters to tune their field emission properties are studied: structure and morphology of CNT cathodes, temperature as well as electronic work function of CNT. Macroscopic CNT cathodes with optimized performance are chosen to build a high-resolution x-ray imaging system. The system can readily generate x-ray radiation with continuous variation of temporal resolution up to nanoseconds and spatial resolution down to 10 micron. Its potential applications for dynamic x-ray imaging and micro-computed tomography are also demonstrated. The performance characteristics of this compact and versatile system are promising for non-destructive testing and for non-invasive small-animal imaging for biomedical research.

Cheng, Yuan

298

Quantifying the emissions and air quality co-benefits of lower-carbon electricity production  

NASA Astrophysics Data System (ADS)

The impact of air emissions from electricity generation depends on the spatial distribution of power plants and electricity dispatch decisions. Thus, any realistic evaluation of the air quality impacts of lower-carbon electricity must account for the spatially heterogeneous changes in associated emissions. Here, we present an analysis of the changes in fine particulate matter (PM2.5) associated with current, expected, and proposed energy efficiency and renewable energy policies in Wisconsin. We simulate the state's electricity system and its potential response to policies using the MyPower electricity-sector model, which calculates plant-by-plant reductions in NOx and SO2 emissions. We find that increased efficiency and renewable generation in a 2024 policy scenario substantially reduce statewide emissions of NOx and SO2 (55% and 59% compared to 2008, 32% and 33% compared to 2024 business-as-usual, BAU). PM2.5 is quantified across the Great Lakes region using the EPA Community Multiscale Air Quality (CMAQ) model for some emissions scenarios. We find that summer mean surface concentrations of sulfate and PM2.5 are less sensitive to policy changes than emissions. In the 2024 policy scenario, sulfate aerosol decreases less than 3% over most of the region relative to BAU and 3-13% relative to 2008 over most of Wisconsin. The lower response of these secondary aerosols arises from chemical and meteorological processing of electricity emissions, and mixing with other emission sources. An analysis of model performance and response to emission reduction at five sites in Wisconsin shows good model agreement with observations and a high level of spatial and temporal variability in sulfate and PM2.5 reductions. In this case study, the marginal improvements in emissions and air quality associated with carbon policies were less than the technology, renewable, and conservation assumptions under a business-as-usual scenario. However, this analysis for Wisconsin shows how integrated modeling can quantify the emission and air quality co-benefits associated with carbon reduction measures, and this approach can be applied to other regions and larger geographical scales.

Plachinski, Steven D.; Holloway, Tracey; Meier, Paul J.; Nemet, Gregory F.; Rrushaj, Arber; Oberman, Jacob T.; Duran, Phillip L.; Voigt, Caitlin L.

2014-09-01

299

Potential of aeration flow rate and bio-char addition to reduce greenhouse gas and ammonia emissions during manure composting.  

PubMed

Aeration is an important factor influencing CO2, CH4, N2O and NH3 emissions from the composting process. Both CH4 and N2O are potent greenhouse gases (GHG) of high importance. Here, we examined the effects of high and low aeration rates together with addition of barley straw with and without bio-char on GHG and NH3 emissions from composting cattle slurry and hen manure in small-scale laboratory composters. Depending on treatment, cumulative C losses via CO2 and CH4 emissions accounted for 11.4-22.5% and 0.004-0.2% of initial total carbon, while N losses as N2O and NH3 emissions comprised 0.05-0.1% and 0.8-26.5% of initial total nitrogen, respectively. Decreasing the flow rate reduced cumulative NH3 losses non-significantly (by 88%) but significantly increased CH4 losses (by 51%) from composting of cattle slurry with barley straw. Among the hen manure treatments evaluated, bio-char addition to composting hen manure and barley straw at low flow rates proved most effective in reducing cumulative NH3 and CH4 losses. Addition of bio-char in combination with barley straw to hen manure at both high and low flow rates reduced total GHG emissions (as CO2-equivalents) by 27-32% compared with barley straw addition alone. Comparisons of flow rates showed that low flow could be an alternative strategy for reducing NH3 losses without any significant change in N2O emissions, pointing to the need for well-controlled composting conditions if gaseous emissions are to be minimised. PMID:24210550

Chowdhury, Md Albarune; de Neergaard, Andreas; Jensen, Lars Stoumann

2014-02-01

300

Irreversible climate change due to carbon dioxide emissions.  

PubMed

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450-600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the "dust bowl" era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4-1.0 m if 21st century CO(2) concentrations exceed 600 ppmv and 0.6-1.9 m for peak CO(2) concentrations exceeding approximately 1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer. PMID:19179281

Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

2009-02-10

301

Field Emission from Individual Free-Standing Carbon Nanotubes  

NASA Astrophysics Data System (ADS)

The field emission (FE) characteristics of individual free-standing vertically aligned carbon nanotubes (VACNTs) grown by inductively coupled plasma chemical vapor deposition (ICP-CVD) were studied. The processes comprised electron beam lithography (EBL) with various exposure periods, the deposition of nickel metal followed by lift-off, and the growth of carbon nanotubes by ICP-CVD on a <100> p-type silicon substrate. Straight tubular and stubby conical VACNFs were formed by varying the size of the graphite electrode that supports the silicon substrate. Current-voltage (I-V) curve characteristics for the tubular shape of isolated carbon nanotubes with different diameters and lengths were studied. The lowest turn-on voltage was shown to be about 24.5 V for the highest aspect ratio of a single vertically-aligned CNT. The highest field enhancement factor ? determined from fitting the FN equation was about 110. In addition, the enhancement factor was proportional to the aspect ratio of the CNTs. The turn-on field at an emission current of 1 nA was 8-12 V/m for a single straight tubular VACNT and 4-8 V/m for a stubby conical VACNF. The stubby conical CNFs (with smaller radii of curvature of their tips) had a lower turn-on field, but a slightly lower ?, than the long tubular CNTs (with higher aspect ratio).

Tseng, Shih-chun; Yao, Bin-cheng; Tsai, Chuen-horng

2010-10-01

302

Field emission, morphological and mechanical properties of variety of diamond-like carbon thin films  

NASA Astrophysics Data System (ADS)

The effect of nitrogen incorporation and sandwich titanium and copper layers, on field emission, morphological and mechanical properties of diamond-like carbon (DLC) thin films is explored. The introduction of foreign element (N2) and sandwich Cu and Ti layers changed the amorphous morphology to nanostructured, reduced the stress, enhanced the hardness (except N2 incorporated DLC film) and improved the field emission (except Ti/DLC bilayer) of modified DLC films. The associated versatile electrical and mechanical properties of modified DLC film made it a material of great utility in the development of field emission display panels and also lead to its application as a hard and protective coating on cutting tools, automobile parts etc. It is important to mention that DLC-based electronic materials may replace currently used soft electronic materials (such as Si) due to their enhanced stability under high energy radiation.

Dwivedi, Neeraj; Kumar, Sushil; Tripathi, R. K.; Malik, H. K.; Panwar, O. S.

2011-11-01

303

Global Carbon Emissions in the Coming Decades: The Case of China  

SciTech Connect

China's annual energy-related carbon emissions surpassed those of the United States in In order to build a more robust understanding of China's energy-related carbon emissions, emissions after 2001? The divergence between actual and forecasted carbon emissions international trade, and central government policies in driving emissions growth. so greatly in error and what drove the rapid growth of China's energy-related carbon this article reviews the role of economic restructuring, urbanization, coal dependence, underscores the rapid changes that have taken place in China's energy system since 2001.

Levine, Mark; Levine, Mark D.; Aden, Nathaniel T.

2008-05-01

304

Emissions of black carbon and co-pollutants emitted from diesel vehicles in the Mexico City Metropolitan Area  

NASA Astrophysics Data System (ADS)

Black carbon emitted from freight, public transport, and heavy duty trucks sources is linked with adverse effects on human health. In addition, the control of emissions of black carbon, an important short-lived climate forcing agent (SLCF), has recently been considered as one of the key strategies for mitigating regional near-term climate change. Despite the availability of new emissions control technologies for reducing emissions from diesel-powered mobile sources, their introduction is still not widespread in many urban areas and there is a need to characterize real-world emission rates of black carbon from this key source. The emissions of black carbon, organic carbon, and other gaseous and particle pollutants from diesel-powered mobile sources in Mexico were characterized by deploying a mobile laboratory equipped with real-time instrumentation in Mexico City as part of the SLCFs-Mexico 2013 project. From February 25-28 of 2013 the emissions from selected diesel-powered vehicles were measured in both controlled experiments and real-world on-road driving conditions. Sampled vehicles had several emissions levels technologies, including: EPA98, EPA03, EPA04, EURO3-5, and Hybrid. All vehicles were sampled using diesel fuel and several vehicles were measured using both diesel and biodiesel fuels. Additional measurements included the use of a remote sensing unit for the co-sampling of all tested vehicles, and the installation and operation of a Portable Emissions Measurements System (PEMS) for the measurement of emissions from a test vehicle. We will present inter-comparisons of the emission factors obtained among the various vehicle technologies that were sampled during the experiment as well as the inter-comparison of results from the various sampling platforms. The results can be used to

Zavala, Miguel; Molina, Luisa T.; Fortner, Edward; Knighton, Berk; Herndon, Scott; Yacovitch, Tara; Floerchinger, Cody; Roscioli, Joseph; Kolb, Charles; Mejia, Jose Antonio; Sarmiento, Jorge; Paramo, Victor Hugo; Zirath, Sergio; Jazcilevich, Aron

2014-05-01

305

Superconducting Ducted Fan Design for Reduced Emissions Aeropropulsion  

Microsoft Academic Search

This article introduces a new conceptual design tool for an environmentally sustainable method of aeropropulsion: a ducted fan system driven by a fully superconducting electrical machine. Such a system could help mitigate aviation's contribution to global climate change by enabling the reduction of greenhouse gas emissions from aircraft. An electro-thermal motor sizing model was coupled with cycle analysis and weight

Philippe J. Masson; Taewoo Nam; Taeyun P. Choi; Pascal Tixador; Mark Waters; David Hall; Cesar A. Luongo; Dimitri N. Mavris

2009-01-01

306

Innovative Technology Reduces Power Plant Emissions - Commercialization Success  

NASA Technical Reports Server (NTRS)

Emission control system development includes: (1) Development of new oxidizer scrubber system to eliminate NOx waste and produce fertilizer (2) Technology licensed and a 1 to 3 MWatt-scale prototype installed on. power plant (3) Development of method to oxidize NO. to N02 (4) Experience gained from licensing NASA technology

Parrish, Clyde

2004-01-01

307

Innovative Technology Reduces Power Plant Emissions-Commercialization Success  

NASA Technical Reports Server (NTRS)

Overview of emission control system development: (1) Development of new oxidizer scrubber system to eliminate NOx waste and produce fertilizer (2) Technology licensed and a 1 to 3 MWatt-scale prototype installed on power plant (3) Development of method to oxidize NO to NO2 (4) Experience gained from licensing NASA technology.

Parrish, Clyde; Chung, Landy

2004-01-01

308

Using Sensor Information to Reduce the Carbon Footprint of Perishable Goods  

Microsoft Academic Search

Sensors enhance the control of perishable goods. New applications not only help to increase profits but also to reduce greenhouse gas emissions. An abatement cost analysis examines the trade-offs between profit maximization and emission minimization.

Alexander Ilic; Thorsten Staake; Elgar Fleisch

2009-01-01

309

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

PubMed

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. PMID:25607824

Yu, Yang; Rajagopal, Ram

2015-02-17

310

Reducing emissions from deforestation and forest degradation (REDD+): game changer or just another quick fix?  

PubMed

Reducing emissions from deforestation and forest degradation (REDD+) provides financial compensation to land owners who avoid converting standing forests to other land uses. In this paper, we review the main opportunities and challenges for REDD+ implementation, including expectations for REDD+ to deliver on multiple environmental and societal cobenefits. We also highlight a recent case study, the Norway-Indonesia REDD+ agreement and discuss how it might be a harbinger of outcomes in other forest-rich nations seeking REDD+ funds. Looking forward, we critically examine the fundamental assumptions of REDD+ as a solution for the atmospheric buildup of greenhouse gas emissions and tropical deforestation. We conclude that REDD+ is currently the most promising mechanism driving the conservation of tropical forests. Yet, to emerge as a true game changer, REDD+ must still demonstrate that it can access low transaction cost and high-volume carbon markets or funds, while also providing or complimenting a suite of nonmonetary incentives to encourage a developing nation's transition from forest losing to forest gaining, and align with, not undermine, a globally cohesive attempt to mitigate anthropogenic climate change. PMID:22168380

Venter, Oscar; Koh, Lian Pin

2012-02-01

311

Inductive pulsed phase thermography for reducing or enlarging the effect of surface emissivity variation  

NASA Astrophysics Data System (ADS)

Emissivity variation introduces illusory temperature inhomogeneity and results in false alarms in infrared thermography, thus, it is important to separate the influence of surface emissivity variation. This letter experimentally demonstrates the advantages of phase information to reduce or enlarge the effect of surface emissivity variation with inductive pulsed phase thermography, where inductive excitation is emissivity-independent and avoids the effect of emissivity variation in heating process. The directly heated area and the indirectly heated area are divided in the phasegrams. The emissivity variation is removed or enlarged perfectly at the specific frequency and defect detectability is improved remarkably.

Yang, Ruizhen; He, Yunze; Gao, Bin; Tian, Gui Yun

2014-11-01

312

Soil organic carbon enrichment of dust emissions: magnitude, mechanisms and its implications for  

E-print Network

emissions are required to eluci- date the significance of wind erosion for the carbon cycle and nationalSoil organic carbon enrichment of dust emissions: magnitude, mechanisms and its implications for the carbon cycle Nicholas P. Webb,1 * Craig L. Strong,2 Adrian Chappell,3 Samuel K. Marx4 and Grant H. Mc

313

Decomposing the Impact of Alternative Technology Sets on Future Carbon Emissions Growth1  

E-print Network

of a global carbon tax and alternative assumptions about the future availability of key energy supplyDecomposing the Impact of Alternative Technology Sets on Future Carbon Emissions Growth1 Karen;1 Decomposing the Impact of Alternative Technology Sets on Future Carbon Emissions Growth ABSTRACT What

Wing, Ian Sue

314

Single-Walled Carbon Nanotubes of Controlled Diameter and Bundle Size and Their Field Emission Properties  

E-print Network

Single-Walled Carbon Nanotubes of Controlled Diameter and Bundle Size and Their Field Emission: June 8, 2005 Field emission studies were conducted on as-produced CoMoCAT single-walled carbon nanotube electron emitter. By adjusting the catalytic synthesis conditions, single-walled carbon nanotubes (SWNT

Resasco, Daniel

315

SunShot solar power reduces costs and uncertainty in future low-carbon electricity systems.  

PubMed

The United States Department of Energy's SunShot Initiative has set cost-reduction targets of $1/watt for central-station solar technologies. We use SWITCH, a high-resolution electricity system planning model, to study the implications of achieving these targets for technology deployment and electricity costs in western North America, focusing on scenarios limiting carbon emissions to 80% below 1990 levels by 2050. We find that achieving the SunShot target for solar photovoltaics would allow this technology to provide more than a third of electric power in the region, displacing natural gas in the medium term and reducing the need for nuclear and carbon capture and sequestration (CCS) technologies, which face technological and cost uncertainties, by 2050. We demonstrate that a diverse portfolio of technological options can help integrate high levels of solar generation successfully and cost-effectively. The deployment of GW-scale storage plays a central role in facilitating solar deployment and the availability of flexible loads could increase the solar penetration level further. In the scenarios investigated, achieving the SunShot target can substantially mitigate the cost of implementing a carbon cap, decreasing power costs by up to 14% and saving up to $20 billion ($2010) annually by 2050 relative to scenarios with Reference solar costs. PMID:23865424

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

2013-08-20

316

Laboratory and field investigations of particulate and carbon monoxide emissions from traditional and improved cookstoves  

NASA Astrophysics Data System (ADS)

We implemented a program in which emission characterization is enabled through collaborations between academic, US and international non-governmental entities that focus on evaluation, dissemination, and in-use testing, of improved cookstoves. This effort resulted in a study of field and laboratory emissions from traditional and improved biofuel cookstoves. We found that field measured particulate emissions of actual cooking average three times those measured during simulated cooking in the laboratory. Emission factors are highly dependent on the care and skill of the operator and the resulting combustion; these do not appear to be accurately reproduced in laboratory settings. The single scattering albedo (SSA) of the emissions was very low in both lab and field measurements, averaging about 0.3 for lab tests and around 0.5 for field tests, indicating that the primary particles are climate warming. Over the course of three summers in Honduras, we measured field emissions from traditional cookstoves, relatively new improved cookstoves, and "broken-in" improved cookstoves. We found that well-designed improved cookstoves can significantly reduce PM and CO emission factors below traditional cookstoves. For improved stoves, the presence of a chimney generally resulted in lower emission factors but left the SSA unaffected. Traditional cookstoves had an average PM emission factor of 8.2 g kg -1 - significantly larger than previous studies. Particulate emission factors for improved cookstoves without and with chimneys averaged about 6.6 g kg -1 and 4.5 g kg -1, respectively. The elemental carbon (EC) fraction of PM varied significantly between individual tests, but averaged about 25% for each of the categories.

Roden, Christoph A.; Bond, Tami C.; Conway, Stuart; Osorto Pinel, Anibal Benjamin; MacCarty, Nordica; Still, Dean

317

Emission factors of PAHs, methoxyphenols, levoglucosan, elemental carbon and organic carbon from simulated wheat and Kentucky bluegrass stubble burns  

Microsoft Academic Search

Emission factors (EFs) of pollutants from post-harvest agricultural burning are required for predicting downwind impacts of smoke and inventorying emissions. EFs of polycyclic aromatic hydrocarbons (PAH), methoxyphenols (MP), levoglucosan (LG), elemental carbon (EC) and organic carbon (OC) from wheat and Kentucky bluegrass (KBG) stubble burning were quantified in a US EPA test burn facility. The PAH and MP EFs for

Ranil Dhammapala; Candis Claiborn; Jorge Jimenez; Jeffrey Corkill; Brian Gullett; Christopher Simpson; Michael Paulsen

2007-01-01

318

Historical emissions of black and organic carbon aerosol from energy-related combustion, 18502000  

Microsoft Academic Search

We present an emission inventory of primary black carbon (BC) and primary organic carbon (OC) aerosols from fossil fuel and biofuel combustion between 1850 and 2000. We reconstruct fossil fuel consumption and represent changes in technology on a national and sectoral basis. Our estimates rely on new estimates of biofuel consumption, and updated emission factors for old technologies. Emissions of

Tami C. Bond; Ekta Bhardwaj; Rong Dong; Rahil Jogani; Soonkyu Jung; Christoph Roden; David G. Streets; Nina M. Trautmann

2007-01-01

319

Woody encroachment reduces nutrient limitation and promotes soil carbon sequestration  

PubMed Central

During the past century, the biomass of woody species has increased in many grassland and savanna ecosystems. As many of these species fix nitrogen symbiotically, they may alter not only soil nitrogen (N) conditions but also those of phosphorus (P). We studied the N-fixing shrub Dichrostachys cinerea in a mesic savanna in Zambia, quantifying its effects upon pools of soil N, P, and carbon (C), and availabilities of N and P. We also evaluated whether these effects induced feedbacks upon the growth of understory vegetation and encroaching shrubs. Dichrostachys cinerea shrubs increased total N and P pools, as well as resin-adsorbed N and soil extractable P in the top 10-cm soil. Shrubs and understory grasses differed in their foliar N and P concentrations along gradients of increasing encroachment, suggesting that they obtained these nutrients in different ways. Thus, grasses probably obtained them mainly from the surface upper soil layers, whereas the shrubs may acquire N through symbiotic fixation and probably obtain some of their P from deeper soil layers. The storage of soil C increased significantly under D.cinerea and was apparently not limited by shortages of either N or P. We conclude that the shrub D.cinerea does not create a negative feedback loop by inducing P-limiting conditions, probably because it can obtain P from deeper soil layers. Furthermore, C sequestration is not limited by a shortage of N, so that mesic savanna encroached by this species could represent a C sink for several decades. We studied the effects of woody encroachment on soil N, P, and C pools, and availabilities of N and P to Dichrostachys cinerea shrubs and to the understory vegetation. Both N and P pools in the soil increased along gradients of shrub age and cover, suggesting that N fixation by D.cinerea did not reduce the P supply. This in turn suggests that continued growth and carbon sequestration in this mesic savanna ecosystems are unlikely to be constrained by nutrient limitation and could represent a C sink for several decades. PMID:24834338

Blaser, Wilma J; Shanungu, Griffin K; Edwards, Peter J; Olde Venterink, Harry

2014-01-01

320

Woody encroachment reduces nutrient limitation and promotes soil carbon sequestration.  

PubMed

During the past century, the biomass of woody species has increased in many grassland and savanna ecosystems. As many of these species fix nitrogen symbiotically, they may alter not only soil nitrogen (N) conditions but also those of phosphorus (P). We studied the N-fixing shrub Dichrostachys cinerea in a mesic savanna in Zambia, quantifying its effects upon pools of soil N, P, and carbon (C), and availabilities of N and P. We also evaluated whether these effects induced feedbacks upon the growth of understory vegetation and encroaching shrubs. Dichrostachys cinerea shrubs increased total N and P pools, as well as resin-adsorbed N and soil extractable P in the top 10-cm soil. Shrubs and understory grasses differed in their foliar N and P concentrations along gradients of increasing encroachment, suggesting that they obtained these nutrients in different ways. Thus, grasses probably obtained them mainly from the surface upper soil layers, whereas the shrubs may acquire N through symbiotic fixation and probably obtain some of their P from deeper soil layers. The storage of soil C increased significantly under D.cinerea and was apparently not limited by shortages of either N or P. We conclude that the shrub D.cinerea does not create a negative feedback loop by inducing P-limiting conditions, probably because it can obtain P from deeper soil layers. Furthermore, C sequestration is not limited by a shortage of N, so that mesic savanna encroached by this species could represent a C sink for several decades. We studied the effects of woody encroachment on soil N, P, and C pools, and availabilities of N and P to Dichrostachys cinerea shrubs and to the understory vegetation. Both N and P pools in the soil increased along gradients of shrub age and cover, suggesting that N fixation by D.cinerea did not reduce the P supply. This in turn suggests that continued growth and carbon sequestration in this mesic savanna ecosystems are unlikely to be constrained by nutrient limitation and could represent a C sink for several decades. PMID:24834338

Blaser, Wilma J; Shanungu, Griffin K; Edwards, Peter J; Olde Venterink, Harry

2014-04-01

321

Carbon Cycles  

NSDL National Science Digital Library

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

Integrated Teaching and Learning Program,

322

The European carbon balance. Part 1: fossil fuel emissions  

SciTech Connect

We analyzed the magnitude, the trends and the uncertainties of fossil-fuel CO2 emissions in the European Union 25 member states (hereafter EU-25), based on emission inventories from energy-use statistics. The stability of emissions during the past decade at EU-25 scale masks decreasing trends in some regions, offset by increasing trends elsewhere. In the recent 4 years, the new Eastern EU-25 member states have experienced an increase in emissions, reversing after a decade-long decreasing trend. Mediterranean and Nordic countries have also experienced a strong acceleration in emissions. In Germany, France and United Kingdom, the stability of emissions is due to the decrease in the industry sector, offset by an increase in the transportation sector. When four different inventories models are compared, we show that the between-models uncertainty is as large as 19% of the mean for EU-25, and even bigger for individual countries. Accurate accounting for fossil CO2 emissions depends on a clear understanding of system boundaries, i.e. emitting activities included in the accounting. We found that the largest source of errors between inventories is the use of distinct systems boundaries (e.g. counting or not bunker fuels, cement manufacturing, nonenergy products). Once these inconsistencies are corrected, the between-models uncertainty can be reduced down to 7% at EU-25 scale. The uncertainty of emissions at smaller spatial scales than the country scale was analyzed by comparing two emission maps based upon distinct economic and demographic activities. A number of spatial and temporal biases have been found among the two maps, indicating a significant increase in uncertainties when increasing the resolution at scales finer than 200 km. At 100km resolution, for example, the uncertainty of regional emissions is estimated to be 60 gCm2 yr1, up to 50% of the mean. The uncertainty on regional fossil-fuel CO2 fluxes to the atmosphere could be reduced by making accurate 14C measurements in atmospheric CO2, and by combining them with transport models.

Ciais, Philippe [Laboratoire des Sciences du Climat et de l'Environement, France; Paris, J. D. [Laboratoire des Sciences du Climat et de l'Environement, France; Peylin, Philippe [National Center for Scientific Research, Gif-sur-Yvette, France; Piao, S. L. [National Center for Scientific Research, Gif-sur-Yvette, France; River, L. [National Center for Scientific Research, Gif-sur-Yvette, France; Marland, Gregg [ORNL; Levin, I. [University of Heidelberg; Pregger, T. [Universitat Stuttgart; Scholz, Y. [Universitat Stuttgart; Friedrich, R. [Universitat Stuttgart; Schulze, E.-D. [Max Planck Institute for Biogeochemistry

2009-05-01

323

Precise measurement of prompt photon emission for carbon ion therapy  

E-print Network

Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments is still a matter of research. A possible technique exploits the information provided by single photon emission from nuclear decays induced by the irradiation. This paper reports the measurements of the spectrum and rate of such photons produced from the interaction of a 80 MeV/u fully stripped carbon ion beam at the Laboratori Nazionali del Sud of INFN, Catania, with a Poly-methyl methacrylate target. The differential production rate for photons with energy E > 2 MeV and emitted at 90 degree is found to be $dN_{\\gamma}/(dN_C d\\Omega)=(2.92\\pm 0.19)\\times 10^{-2}$sr$^{-1}$.

Agodi, C; Cirrone, G A P; Collamati, F; Cuttone, G; De Lucia, E; De Napoli, M; Di Domenico, A; Faccini, R; Ferroni, F; Fiore, S; Gauzzi, P; Iarocci, E; Marafini, M; Mattei, I; Paoloni, A; Patera, V; Piersanti, L; Romano, F; Sarti, A; Sciubba, A; Voena, C

2011-01-01

324

Battery-Powered Electric and Hybrid Electric Vehicle Projects to Reduce Greenhouse Gas Emissions: A Resource for Project Development  

SciTech Connect

The transportation sector accounts for a large and growing share of global greenhouse gas (GHG) emissions. Worldwide, motor vehicles emit well over 900 million metric tons of carbon dioxide (CO2) each year, accounting for more than 15 percent of global fossil fuel-derived CO2 emissions.1 In the industrialized world alone, 20-25 percent of GHG emissions come from the transportation sector. The share of transport-related emissions is growing rapidly due to the continued increase in transportation activity.2 In 1950, there were only 70 million cars, trucks, and buses on the worlds roads. By 1994, there were about nine times that number, or 630 million vehicles. Since the early 1970s, the global fleet has been growing at a rate of 16 million vehicles per year. This expansion has been accompanied by a similar growth in fuel consumption.3 If this kind of linear growth continues, by the year 2025 there will be well over one billion vehicles on the worlds roads.4 In a response to the significant growth in transportation-related GHG emissions, governments and policy makers worldwide are considering methods to reverse this trend. However, due to the particular make-up of the transportation sector, regulating and reducing emissions from this sector poses a significant challenge. Unlike stationary fuel combustion, transportation-related emissions come from dispersed sources. Only a few point-source emitters, such as oil/natural gas wells, refineries, or compressor stations, contribute to emissions from the transportation sector. The majority of transport-related emissions come from the millions of vehicles traveling the worlds roads. As a result, successful GHG mitigation policies must find ways to target all of these small, non-point source emitters, either through regulatory means or through various incentive programs. To increase their effectiveness, policies to control emissions from the transportation sector often utilize indirect means to reduce emissions, such as requiring specific technology improvements or an increase in fuel efficiency. Site-specific project activities can also be undertaken to help decrease GHG emissions, although the use of such measures is less common. Sample activities include switching to less GHG-intensive vehicle options, such as electric vehicles (EVs) or hybrid electric vehicles (HEVs). As emissions from transportation activities continue to rise, it will be necessary to promote both types of abatement activities in order to reverse the current emissions path. This Resource Guide focuses on site- and project-specific transportation activities. .

National Energy Technology Laboratory

2002-07-31

325

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

PubMed Central

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 19892008 deforestation (93%) and net carbon emissions (69%), by 20072008, 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 (19942001), shifting to 69% peatlands (20082011). 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

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

326

Performance of a carbon nanotube field emission electron gun  

NASA Astrophysics Data System (ADS)

A cold cathode field emission electron gun (e-gun) based on a patterned carbon nanotube (CNT) film has been fabricated for use in a miniaturized reflectron time-of-flight mass spectrometer (RTOF MS), with future applications in other charged particle spectrometers, and performance of the CNT e-gun has been evaluated. A thermionic electron gun has also been fabricated and evaluated in parallel and its performance is used as a benchmark in the evaluation of our CNT e-gun. Implications for future improvements and integration into the RTOF MS are discussed.

Getty, Stephanie A.; King, Todd T.; Bis, Rachael A.; Jones, Hollis H.; Herrero, Federico; Lynch, Bernard A.; Roman, Patrick; Mahaffy, Paul

2007-04-01

327

Management options for reducing CO2 emissions from agricultural soils  

Microsoft Academic Search

Crop-based agriculture occupies 1.7 billion hectares, globally, with a soil C stock of about 170 Pg. Of the past anthropogenic CO2 additions to the atmosphere, about 50 Pg C came from the loss of soil organic matter (SOM) in cultivated soils. Improved management practices, however, can rebuild C stocks in agricultural soils and help mitigate CO2 emissions. Increasing soil C

K. PAUSTIAN; E. T. ELLIOTT; H. W. HUNT

2000-01-01

328

Stable Electron Field Emission afrom Opened-Tip Carbon Nanotube Bundles  

NASA Astrophysics Data System (ADS)

Effective electron field emission from carbon nanotubes (CNTs) has been known for years but reliable commercial devices are still not available. Most reported works describe low emission threshold field (Eth) of CNTs and their device architectures. However, fundamental factors that determine stable emission from CNTs are still not clear. We previously reported that graphitic order of CNTs affects their emission stability [1]. Here, we found that both opened tip nanotubes and bundling, when introduced independently, can reduce Eth of CNTs and enhance the emission stability. The combined of both factors, i.e., opened tip nanotube bundles are shown to emit electron continuously > ten hours with notable stability. Theoretical simulation was conducted in supporting our explanation on these enhanced emission properties. SEM, TEM and Raman spectroscopy was conducted to characterize the as grown CNTs. Y. K. Yap acknowledges support from the Defense Advanced Research Projects Agency (DAAD17-03-C-0115, through Army Research Laboratory). [1]. Kayastha et al, Nanotechnology 18, 035206 (2007).

Pandey, Archana; Prasad, Abhishek; Moscatello, Jason; Khin Yap, Yoke

2009-03-01

329

Improved field emission performance of carbon nanotube by introducing copper metallic particles  

NASA Astrophysics Data System (ADS)

To improve the field emission performance of carbon nanotubes (CNTs), a simple and low-cost method was adopted in this article. We introduced copper particles for decorating the CNTs so as to form copper particle-CNT composites. The composites were fabricated by electrophoretic deposition technique which produced copper metallic particles localized on the outer wall of CNTs and deposited them onto indium tin oxide (ITO) electrode. The results showed that the conductivity increased from 10-5 to 4 10-5 S while the turn-on field was reduced from 3.4 to 2.2 V/?m. Moreover, the field emission current tended to be undiminished after continuous emission for 24 h. The reasons were summarized that introducing copper metallic particles to decorate CNTs could increase the surface roughness of the CNTs which was beneficial to field emission, restrain field emission current from saturating when the applied electric field was above the critical field. In addition, it could also improve the electrical contact by increasing the contact area between CNT and ITO electrode that was beneficial to the electron transport and avoided instable electron emission caused by thermal injury of CNTs.

Chen, Yiren; Jiang, Hong; Li, Dabing; Song, Hang; Li, Zhiming; Sun, Xiaojuan; Miao, Guoqing; Zhao, Haifeng

2011-10-01

330

Improved field emission performance of carbon nanotube by introducing copper metallic particles.  

PubMed

To improve the field emission performance of carbon nanotubes (CNTs), a simple and low-cost method was adopted in this article. We introduced copper particles for decorating the CNTs so as to form copper particle-CNT composites. The composites were fabricated by electrophoretic deposition technique which produced copper metallic particles localized on the outer wall of CNTs and deposited them onto indium tin oxide (ITO) electrode. The results showed that the conductivity increased from 10-5 to 4 10-5 S while the turn-on field was reduced from 3.4 to 2.2 V/?m. Moreover, the field emission current tended to be undiminished after continuous emission for 24 h. The reasons were summarized that introducing copper metallic particles to decorate CNTs could increase the surface roughness of the CNTs which was beneficial to field emission, restrain field emission current from saturating when the applied electric field was above the critical field. In addition, it could also improve the electrical contact by increasing the contact area between CNT and ITO electrode that was beneficial to the electron transport and avoided instable electron emission caused by thermal injury of CNTs. PMID:21968066

Chen, Yiren; Jiang, Hong; Li, Dabing; Song, Hang; Li, Zhiming; Sun, Xiaojuan; Miao, Guoqing; Zhao, Haifeng

2011-01-01

331

Improved field emission performance of carbon nanotube by introducing copper metallic particles  

PubMed Central

To improve the field emission performance of carbon nanotubes (CNTs), a simple and low-cost method was adopted in this article. We introduced copper particles for decorating the CNTs so as to form copper particle-CNT composites. The composites were fabricated by electrophoretic deposition technique which produced copper metallic particles localized on the outer wall of CNTs and deposited them onto indium tin oxide (ITO) electrode. The results showed that the conductivity increased from 10-5 to 4 10-5 S while the turn-on field was reduced from 3.4 to 2.2 V/?m. Moreover, the field emission current tended to be undiminished after continuous emission for 24 h. The reasons were summarized that introducing copper metallic particles to decorate CNTs could increase the surface roughness of the CNTs which was beneficial to field emission, restrain field emission current from saturating when the applied electric field was above the critical field. In addition, it could also improve the electrical contact by increasing the contact area between CNT and ITO electrode that was beneficial to the electron transport and avoided instable electron emission caused by thermal injury of CNTs. PMID:21968066

2011-01-01

332

Do volcanic emissions affect carbon gas fluxes in peatlands?  

NASA Astrophysics Data System (ADS)

Recently, a link has been suggested between volcanic deposition of SO4 and the suppression of CH4 emissions in northern peatlands (Gauci et al., 2008). This link stems from the widely accepted idea that acid rain SO4 additions to peatlands can cause a shift in microbial communities as SO4 reducing bacteria out-compete methanogens for substrates, which results in a suppression of CH4 emission. However, volcanic emissions contain besides S other chemically reactive species that are potentially harmful to the environment. In particular, gaseous and particulate F emissions from volcanoes constitute a steady or intermittent source of F emission and deposition into the environment both close to the source and within fallout range of large eruptions. The objective of this study was to investigate the effect of volcanic depositions of SO4, both alone and in combination with F, on CH4 emission in peatlands. Peat mesocosms collected from Pennine uplands in the UK were treated with weekly pulses of Na2SO4 and NaF over 20 weeks in doses of 74 kg SO4/ ha and 13.5 and 135 kg F /ha. CH4 emissions were measured at regular intervals by taking headspace samples, which were analysed by GC-FID. CO2 fluxes were also measured using a portable Infra Red Gas Analyser (IRGA). No significant differences in CH4 and CO2 emissions were observed for any of the treatments when compared to the controls, which had only received deionised water. These findings are in contrast with previous studies where SO4 reduces CH4 emission in peatlands. The reason for this is unclear but may be due to the heterogeneous nature of peat soils. An alternative explanation relates to the previous history of the soils used in the mesocosms which are known to have been previously exposed to large volumes of anthropogenic S pollution. This may have caused microbial communities to evolve and become acclimatised to high levels of S addition. In either case, the assumption that CH4 suppression in peatlands occurs upon exposure to volcanic depositions is questionable. Gauci, V., S. Blake, et al. (2008). Halving of the northern wetland methane source by a large icelandic volcanic eruption. JGR, doi:10.1029/2007JG000499

Harrison, Nicola; Delmelle, Pierre; Toet, Sylvia; Gauci, Vincent; Ineson, Phil

2010-05-01

333

Field electron emission of multiwalled carbon nanotubes and carbon nanofibers grown from Camphor  

NASA Astrophysics Data System (ADS)

Vertically aligned carbon nanofibers (CNF) and multiwalled carbon nanotubes (MWCN) were synthesized from camphor by catalytic thermal chemical vapor deposition on Co and Co/Fe thin films (for CNF) and on silicon substrates using a mixture of camphor and ferrocene (for MWCN). CNF and MWCN were studied by scanning and transmission electron microscopy, visible Raman spectroscopy, X-ray diffraction in order to get insight into the microstructure and morphology of these materials. Field electron emission study indicates turn-on field of about 1.52, 2.3 and 4.3 V/?m for MWCN, Co/CNF and Co/Fe/CNF films, respectively; and threshold field of about 2.48, 3.1 and 6 V/?m, respectively. Our study indicates a better performance for field electron emission compared with some of the earlier published reports which might be due to higher aspect ratio, good graphitization and suitable density.

Somani, Savita P.; Somani, Prakash R.; Yoshida, A.; Tanemura, M.; Lau, S. P.; Umeno, M.

2008-06-01

334

Technology Opportunities to Reduce U.S. Greenhouse Gas Emissions  

SciTech Connect

This report serves as the technology basis of a needed national climate change technology strategy, with the confidence that a strong technology R&D program will deliver a portfolio of technologies with the potential to provide very substantial greenhouse gas emission reductions along with continued economic growth. Much more is needed to define such a strategy, including identification of complementary deployment policies and analysis to support the seeping and prioritization of R&D programs. A national strategy must be based upon governmental, industrial, and academic partnerships.

Not Available

1997-10-01

335

Spatial and temporal patterns of carbon emissions from forest fires in China from 1950 to 2000  

E-print Network

.1029/2005JD006198. 1. Introduction [2] Forest ecosystems play an important role in the global carbon cycle on the carbon cycle include both the direct release of carbon-containing trace gases into atmosphere throughSpatial and temporal patterns of carbon emissions from forest fires in China from 1950 to 2000

336

A Systems Approach to Reducing Institutional GHG Emissions  

ERIC Educational Resources Information Center

Purpose: The purpose of this paper is to establish necessity and methods for considering greenhouse gas (GHG) mitigation policies at a system-level. The research emphasizes connecting narrowly focused GHG mitigation objectives (e.g. reduce single occupancy vehicle travel) with broader institutional objectives (e.g. growth in student population) to

Williamson, Sean R.

2012-01-01

337

Optimization of operational aircraft parameters Reducing Noise Emission  

E-print Network

The objective of this paper is to develop a model and a minimization method to provide flight path optimums reducing aircraft noise in the vicinity of airports. Optimization algorithm has solved a complex optimal control problem, and generates flight paths minimizing aircraft noise levels. Operational and safety constraints have been considered and their limits satisfied. Results are here presented and discussed.

Abdallah, Lina; Khardi, Salah

2008-01-01

338

Fire Impact on Carbon Storage and Emissions in Ecosystems of the Altai-Sayan Ecoregion, Siberia  

NASA Astrophysics Data System (ADS)

Boreal forests contribute considerably to global carbon budget, since they take up vast areas, accumulate much carbon and are sensible to climatic changes. Fires cover annually millions ha of boreal forests, of which the biggest part is in Siberia. Emissions released from biomass burning influence atmospheric chemistry and global carbon cycling. Changing climate and land use affect the number and intensity of wildfires, forest state and carbon emission. In the Altai-Sayan ecoregion found in the south of Siberia and more than a thousand of fires occur annually. We calculated carbon emissions from fires for this region using data on burned biomass. The data was determined by estimating pre- and post-fire fuel biomass using our experimental data obtained in the course of large-scale experiments on fire behavior modeling in various types of Siberian forest. Calculations were made taking account of fire type which determines the contribution of different fuel types to the overall carbon emission, and the fire severity. Maximum emissions from surface fires are observed in May that corresponds to the month with the largest area burned. Because fires occur mainly in spring and spread as running fires, the contribution of duff in carbon emissions is from 15 to 23%. Crown fires occurring in protected areas increase carbon emissions by 4-9%. Release of carbon into the atmosphere from the combustion of biomass constitutes 11% of the total stock of above-ground organic matter in the burned area. Keywords: wildfires, boreal forests, carbon emissions, Siberia

Ivanova, Galina; Ivanov, Valery; Kukavskaya, Elena; Ponomarev, Evgeny

2013-04-01

339

Emissions of carbon monoxide and carbon dioxide from uncompressed and pelletized biomass fuel burning in typical household stoves in China  

NASA Astrophysics Data System (ADS)

Carbon dioxide (CO2) and carbon monoxide (CO) impact climate change and human health. The uncertainties in emissions inventories of CO2 and CO are primarily due to the large variation in measured emissions factors (EFs), especially to the lack of EFs from developing countries. China's goals of reducing CO2 emissions require a maximum utilization of biomass fuels. Pelletized biomass fuels are well suited for the residential biomass market, providing possibilities of more automated and optimized systems with higher modified combustion efficiency (MCE) and less products from incomplete combustion. However, EFs of CO2 and CO from pellet biomass fuels are seldom reported, and a comparison to conventional uncompressed biomass fuels has never been conducted. Therefore, the objectives of this study were to experimentally determine the CO2 and CO EFs from uncompressed biomass (i.e., firewood and crop residues) and biomass pellets (i.e., pine wood pellet and corn straw pellet) under real residential applications and to compare the influences of fuel properties and combustion conditions on CO2 and CO emissions from the two types of biomass fuels. For the uncompressed biomass examples, the CO2 and CO EFs were 1649.4 35.2 g kg-1 and 47.8 8.9 g kg-1, respectively, for firewood and 1503.2 148.5 g kg-1 and 52.0 14.2 g kg-1, respectively, for crop residues. For the pellet biomass fuel examples, the CO2 and CO EFs were 1708.0 3.8 g kg-1 and 4.4 2.4 g kg-1, respectively, for pellet pine and 1552.1 16.3 g kg-1 and 17.9 10.2 g kg-1, respectively, for pellet corn. In rural China areas during 2007, firewood and crop residue burning produced 721.7 and 23.4 million tons of CO2 and CO, respectively.

Wei, Wen; Zhang, Wei; Hu, Dan; Ou, Langbo; Tong, Yindong; Shen, Guofeng; Shen, Huizhong; Wang, Xuejun

2012-09-01

340

Chemical Vapor Deposition of Carbon Nanotubes on Monolayer Graphene Substrates: Reduced Etching via Suppressed Catalytic  

E-print Network

and dramatically reduces the etching of the graphene layer to exhibit graphene-CNT hybrids with continuous nanostructures such as carbon nanofibers5,6 or nanotubes7,8 directly on graphene9 to yield hybrid 3DChemical Vapor Deposition of Carbon Nanotubes on Monolayer Graphene Substrates: Reduced Etching via

Fisher, Frank

341

Tropospheric ozone reduces carbon assimilation in trees: estimates from analysis of continuous flux measurements  

E-print Network

Tropospheric ozone reduces carbon assimilation in trees: estimates from analysis of continuous flux Abstract High ground-level ozone concentrations are typical of Mediterranean climates. Plant exposure to this oxidant is known to reduce carbon assimilation. Ozone damage has been traditionally measured through

Silver, Whendee

342

Synthesis and electron emission properties of aligned carbon nanotube arrays  

NASA Astrophysics Data System (ADS)

Carbon nanotubes (CNTs) have become one of the most interesting allotropes of carbon due to their intriguing mechanical, electrical, thermal and optical properties. The synthesis and electron emission properties of CNT arrays have been investigated in this work. Vertically aligned CNTs of different densities were synthesized on copper substrate with catalyst dots patterned by nanosphere lithography. The CNTs synthesized with catalyst dots patterned by spheres of 500 nm diameter exhibited the best electron emission properties with the lowest turn-on/threshold electric fields and the highest field enhancement factor. Furthermore, CNTs were treated with NH3 plasma for various durations and the optimum enhancement was obtained for a plasma treatment of 1.0 min. CNT point emitters were also synthesized on a flat-tip or a sharp-tip to understand the effect of emitter geometry on the electron emission. The experimental results show that electron emission can be enhanced by decreasing the screening effect of the electric field by neighboring CNTs. In another part of the dissertation, vertically aligned CNTs were synthesized on stainless steel (SS) substrates with and without chemical etching or catalyst deposition. The density and length of CNTs were determined by synthesis time. For a prolonged growth time, the catalyst activity terminated and the plasma started etching CNTs destructively. CNTs with uniform diameter and length were synthesized on SS substrates subjected to chemical etching for a period of 40 minutes before the growth. The direct contact of CNTs with stainless steel allowed for the better field emission performance of CNTs synthesized on pristine SS as compared to the CNTs synthesized on Ni/Cr coated SS. Finally, fabrication of large arrays of free-standing vertically aligned CNT/SnO2 core-shell structures was explored by using a simple wet-chemical route. The structure of the SnO2 nanoparticles was studied by X-ray diffraction and electron microscopy. Transmission electron microscopy reveals that a uniform layer of SnO2 is conformally coated on every tapered CNT. The strong adhesion of CNTs with SS guaranteed the formation of the core-shell structures of CNTs with SnO2 or other metal oxides, which are expected to have applications in chemical sensors and lithium ion batteries.

Neupane, Suman

343

Method and apparatus for reducing solvent luminescence background emissions  

DOEpatents

The detectability of luminescent molecules in solution is enhanced by reducing the background luminescence due to impurity species also present in the solution. A light source that illuminates the solution acts to photolyze the impurities so that the impurities do not luminesce in the fluorescence band of the molecule of interest. Molecules of interest may be carried through the photolysis region in the solution or may be introduced into the solution after the photolysis region.

Affleck, Rhett L. (Los Alamos, NM); Ambrose, W. Patrick (Los Alamos, NM); Demas, James N. (Charlottesville, VA); Goodwin, Peter M. (Jemez Springs, NM); Johnson, Mitchell E. (Pittsburgh, PA); Keller, Richard A. (Los Alamos, NM); Petty, Jeffrey T. (Los Alamos, NM); Schecker, Jay A. (Santa Fe, NM); Wu, Ming (Los Alamos, NM)

1998-01-01

344

Method and apparatus for reducing solvent luminescence background emissions  

DOEpatents

The detectability of luminescent molecules in solution is enhanced by reducing the background luminescence due to impurity species also present in the solution. A light source that illuminates the solution acts to photolyze the impurities so that the impurities do not luminesce in the fluorescence band of the molecule of interest. Molecules of interest may be carried through the photolysis region in the solution or may be introduced into the solution after the photolysis region. 6 figs.

Affleck, R.L.; Ambrose, W.P.; Demas, J.N.; Goodwin, P.M.; Johnson, M.E.; Keller, R.A.; Petty, J.T.; Schecker, J.A.; Wu, M.

1998-10-27

345

Accounting for Carbon Dioxide Emissions from Biomass Energy Combustion (released in AEO2010)  

EIA Publications

Carbon Dioxide (CO2) emissions from the combustion of biomass to produce energy are excluded from the energy-related CO2 emissions reported in Annual Energy Outlook 2010. According to current international convention, carbon released through biomass combustion is excluded from reported energy-related emissions. The release of carbon from biomass combustion is assumed to be balanced by the uptake of carbon when the feedstock is grown, resulting in zero net emissions over some period of time]. However, analysts have debated whether increased use of biomass energy may result in a decline in terrestrial carbon stocks, leading to a net positive release of carbon rather than the zero net release assumed by its exclusion from reported energy-related emissions.

2010-01-01

346

Tillage, Cropping Sequence, and Nitrogen Fertilization Effects on Dryland Soil Carbon Dioxide Emission and Carbon Content  

Technology Transfer Automated Retrieval System (TEKTRAN)

Management practices are needed to reduce dryland soil CO2 emission and increase C sequestration that can influence global warming. We evaluated the effects of tillage and cropping sequence combination and N fertilization on dryland soil surface CO2 flux, temperature and water content at the 0- to 1...

347

Using surface water application to reduce 1,3-dichloropropene emission from soil fumigation.  

PubMed

High emissions from soil fumigants increase the risk of detrimental impact on workers, bystanders, and the environment, and jeopardize future availability of fumigants. Efficient and cost-effective approaches to minimize emissions are needed. This study evaluated the potential of surface water application (or water seal) to reduce 1,3-dichloropropene (1,3-D) emissions from soil (Hanford sandy loam) columns. Treatments included dry soil (control), initial water application (8 mm of water just before fumigant application), initial plus a second water application (2.6 mm) at 12 h, initial plus two water applications (2.6 mm each time) at 12 and 24 h, standard high density polyethylene (HDPE) tarp, initial water application plus HDPE tarp, and virtually impermeable film (VIF) tarp. Emissions from the soil surface and distribution of 1,3-D in the soil-gas phase were monitored for 2 wk. Each water application abruptly reduced 1,3-D emission flux, which rebounded over a few hours. Peak emission rates were substantially reduced, but total emission reduction was small. Total fumigant emission was 51% of applied for the control, 46% for initial water application only, and 41% for the three intermittent water applications with the remaining water treatment intermediate. The HDPE tarp alone resulted in 45% emission, while initial water application plus HDPE tarp resulted in 38% emission. The most effective soil surface treatment was VIF tarp (10% emission). Surface water application can be as effective, and less expensive than, standard HDPE tarp. Frequent water application is required to substantially reduce emissions. PMID:16738389

Gao, Suduan; Trout, Thomas J

2006-01-01

348

Genetic parameters for predicted methane production and potential for reducing enteric emissions through genomic selection  

Microsoft Academic Search

Mitigation of enteric methane (CH4) emission in ruminants has become an important area of research because accumulation of CH4 is linked to global warming. Nutritional and microbial opportunities to reduce CH4 emissions have been extensively researched, but little is known about using natural variation to breed animals with lower CH4 yield. Measuring CH4 emission rates directly from animals is difficult

Haas de Y; J. J. Windig; M. P. L. Calus; J. Dijkstra; Haan de M; A. Bannink; R. F. Veerkamp

2011-01-01

349

Methane oxidation associated with submerged brown mosses reduces methane emissions from Siberian  

E-print Network

Methane oxidation associated with submerged brown mosses reduces methane emissions from Siberian (methanotrophy) associated with submerged brown moss species occurs in polygonal tundra environments of the Siberian Arctic. Methanotrophic bacteria living in close association with mosses are thus not restricted

Wehrli, Bernhard

350

APPLICATION OF POLLUTION PREVENTION TECHNIQUES TO REDUCE INDOOR AIR EMISSIONS FROM ENGINEERED WOOD PRODUCTS  

EPA Science Inventory

The report gives results of an investigation of pollution prevention options to reduce indoor emissions from a type of finished engineered wood. Emissions were screened from four types of finished engineered wood: oak-veneered particleboard coated and cured with a heat-curable, a...

351

A new method to thermally manage an electronic control unit while reducing radiated emissions  

Microsoft Academic Search

This paper provides a methodology to thermally manage an electronic control unit while reducing its radiated emissions. Measurements of the radiated emission levels for a particular electronic control unit revealed excessive levels. Electronic control units utilize pulse width modulated signals to control an external load. The rise and fall times of the pulse width modulated signal impact both the radiated

Imad Sharaa; Daniel N. Aloi

2008-01-01

352

Methods for exploring management options to reduce greenhouse gas emissions from tropical grazing systems  

Microsoft Academic Search

Increasing atmospheric concentrations of greenhouse gases are expected to result in global climatic changes over the next decades. Means of evaluating and reducing greenhouse gas emissions are being sought. In this study an existing simulation model of a tropical savanna woodland grazing system was adapted to account for greenhouse gas emissions. This approach may be able to be used in

S. Mark Howden; David H. White; Greg M. Mckeon; Joe C. Scanlan; John O. Carter

1994-01-01

353

Carbon emission and sequestration of urban turfgrass systems in Hong Kong.  

PubMed

Climate change is more than just a global issue. Locally released carbon dioxide may lead to a rise in global ambient temperature and influence the surrounding climate. Urban greenery may mitigate this as they can remove carbon dioxide by storing carbon in substrates and vegetation. On the other hand, urban greenery systems which are under intense management and maintenance may contribute to the emission of carbon dioxide or other greenhouse gases. The impact of urban greenery on carbon balance in major metropolitan areas thus remains controversial. We investigated the carbon footprints of urban turf operation and maintenance by conducting a research questionnaire on different Hong Kong turfs in 2012, and showed that turf maintenance contributed 0.17 to 0.63 kg Ce m(-2)y(-1) to carbon emissions. We also determined the carbon storage of turfs at 0.05 to 0.21 kg C m(-2) for aboveground grass biomass and 1.26 to 4.89 kg C m(-2) for soils (to 15 cm depth). We estimated that the carbon sink capacity of turfs could be offset by carbon emissions in 5-24 years under current management patterns, shifting from carbon sink to carbon source. Our study suggested that maintenance management played a key role in the carbon budget and footprint of urban greeneries. The environmental impact of turfgrass systems can be optimized by shifting away from empirically designed maintenance schedules towards rational ones based on carbon sink and emission principles. PMID:24365589

Kong, Ling; Shi, Zhengjun; Chu, L M

2014-03-01

354

Greenhouse Gas Emission Accounting and Management of Low-Carbon Community  

PubMed Central

As the major source of greenhouse gas (GHG) emission, cities have been under tremendous pressure of energy conservation and emission reduction for decades. Community is the main unit of urban housing, public facilities, transportation, and other properties of city's land use. The construction of low-carbon community is an important pathway to realize carbon emission mitigation in the context of rapid urbanization. Therefore, an efficient carbon accounting framework should be proposed for CO2 emissions mitigation at a subcity level. Based on life-cycle analysis (LCA), a three-tier accounting framework for the carbon emissions of the community is put forward, including emissions from direct fossil fuel combustion, purchased energy (electricity, heat, and water), and supply chain emissions embodied in the consumption of goods. By compiling a detailed CO2 emission inventory, the magnitude of carbon emissions and the mitigation potential in a typical high-quality community in Beijing are quantified within the accounting framework proposed. Results show that emissions from supply chain emissions embodied in the consumption of goods cannot be ignored. Specific suggestions are also provided for the urban decision makers to achieve the optimal resource allocation and further promotion of low-carbon communities. PMID:23251104

Song, Dan; Su, Meirong; Yang, Jin; Chen, Bin

2012-01-01

355

Brown carbon in fresh and aged biomass burning emissions  

NASA Astrophysics Data System (ADS)

To date, most climate forcing calculations treat black carbon (BC) and dust as the only particulate light absorbers. Numerous studies have shown that some organic aerosols (OA), referred to as brown carbon (BrC), also absorb light. BrC has been identified in biomass burning emissions; however, its light absorption properties are poorly constrained. Literature values of the imaginary part of the refractive indices of biomass burning OA (kOA) span two orders of magnitude. This variability, attributed to differences in fuel type and burning conditions, complicates the representation of biomass burning BrC in climate models. Proper accounting for BrC absorption in climate forcing calculations is of great importance. It can enhance the models' performance, bringing estimates of climate sensitivity to better agreement with observations. Here, we investigate the source of variability in absorptivity of biomass-burning OA observed in this study. We show that absorptivity is closely linked to OA volatility. Specifically, low-volatility organic compounds (LVOCs) are responsible for most of the light absorption, with effective kOA 1-2 orders of magnitude greater than the semi-volatile organic compounds (SVOCs). The effective kOA of biomass-burning emissions thus depends on the extent to which SVOCs partition to the condensed phase, which is sensitive to OA loading. kOA increases by a factor of 3-4 when the emissions are diluted from source concentrations (1-10 mg/m3) to atmospheric-like concentrations (1-10 ?g/m3), as the partitioning of SVOCs shifts towards the gas phase. More importantly, we demonstrate that the effective kOA depends largely on burn conditions, and not fuel type. Burns which produce high levels of BC emit OA that is more absorptive than burns which produce low levels of BC. The dependence of kOA on OA loading and burn conditions can be parameterized as a function of a single property of the emissions, namely the BC-to-OA ratio. Specifically, kOA at wavelength (lambda) of 550 nm increases linearly with the BC-to-OA ratio, while the spectral-dependence, w, where kOA = kOA,550nm*(550/lambda)w, is inversely proportional to the BC-to-OA ratio. These correlations were determined by examining emissions from small scale laboratory burns of six globally relevant fuels (black spruce, ponderosa pine, hay, rice straw, saw grass, and wire grass), assuming that their behavior can be extrapolated to other biomass fuels. Experiments were conducted during the Fire Laboratory at Missoula Campaign (FLAME 4). The BC-to-OA ratios in the experiments were between 0.01 and 0.2. Aging of the emissions (photo-oxidation or dark ozonolysis) was performed in a smog chamber. To determine the dependence of absorptivity on volatility, the SVOCs were stripped from the condensed phase by heating the emissions to 250 C inside a thermodenuder. This allowed for constraining the optical properties of the low-volatility residue. kOA values were retrieved by performing optical closure, which combines Mie theory calculations with measurements of light absorption, and total and BC size distributions.

Saleh, R.; Robinson, E.; Tkacik, D. S.; Ahern, A.; Liu, S.; Aiken, A. C.; Sullivan, R. C.; Presto, A. A.; Dubey, M.; Donahue, N. M.; Robinson, A. L.

2013-12-01

356

Effect of water seal on reducing 1,3-dichloropropene emissions from different soil textures.  

PubMed

Soil physical conditions can affect diffusion, environmental fate, and efficacy of fumigants in soil disinfestation treatments. Water seals (applying water using sprinklers to soil following fumigation) can effectively reduce fumigant emissions from sandy loam soils. Soil column studies compared the effectiveness of water seals in reducing cis-1,3-dichloropropene (1,3-D) emissions from three different textured soils (loamy sand, sandy loam, and loam). Treatments included an untreated control, an initial water seal (9 mm water applied immediately before fumigant injection), and intermittent water seals (initial 9 mm water seal followed by 3 mm at 12 and 24 h). For the loamy sand, instead of the initial water seal treatment, a reduced-amount intermittent water seal (initial 3 mm water followed by 1 mm at 12 and 24 h) treatment was tested. Overall emission loss of 1,3-D from the control over 2 wk was 56% for the loamy sand, 51% for the sandy loam, and 43% for the loam. The initial water seal reduced total 1,3-D emissions to 46% in the sandy loam and 31% in the loam. The intermittent water seals reduced emission loss to 26% for the loamy sand, 41% for the sandy loam, and 21% for the loam. The reduced-amount intermittent water seal for loamy sand had little effect. Low emission loss was associated with high surface soil water content. None of the water applications reduced gaseous fumigant concentrations. Results indicate that water seal techniques may be able to effectively reduce emissions for different soil textures without reducing fumigant concentration in the soil. PMID:19244492

McDonald, Jason A; Gao, Suduan; Qin, Ruijun; Hanson, Bradley D; Trout, Thomas J; Wang, Dong

2009-01-01

357

Magnetoacoustic Emission Characteristics on Cold Rolled Low Carbon Steel  

NASA Astrophysics Data System (ADS)

This paper describes the behaviours of magnetoacoustic emission (MAE) of cold rolled low carbon steel specimens. The MAE rms voltage and the moving average analysis were used for evaluating the profiles of MAE signals. The MAE rms voltage and the peak value of averaged rms voltage rise rapidly with increasing cold rolling below 10 % reduction ratio, and then they decreases at higher reduction ratio, whereas the magnetizing current when the averaged rms voltage takes a peak decreases up to 10 % reduction ratio, then becomes constant value. As a result of the observation of microstructures by transmission electron microscopy, the dislocations increases homogeneously up to 10 % reduction ratio, and then forms cell structures without a significant increase in dislocation density. The behaviours of MAE are attributed to the combined effects of cell texture and dislocation density.

Kikuchi, H.; Matsumura, K.; Fujiwara, T.; Ara, K.; Kamada, Y.; Kobayashi, S.

2011-01-01

358

Surface seals reduce 1,3-dichloropropene and chloropicrin emissions in field tests.  

PubMed

Reducing emissions is essential for minimizing the impact of soil fumigation on the environment. Water application to the soil surface (or water seal) has been demonstrated to reduce 1,3-dichloropropene (1,3-D) emissions in soil column tests. This study determined the effectiveness of water application to reduce emissions of 1,3-D and chloropicrin (CP) in comparison to other surface seals under field conditions. In a small-plot field trial on a Hanford sandy loam soil (coarse-loamy, mixed, superactive, nonacid, thermic Typic Xerorthents) in the San Joaquin Valley, CA. Telone C35 (61% 1,3-D and 35% CP) was shank-applied at a depth of 46 cm at a rate of 610 kg ha-1. Soil surface seal treatments included control (no tarp and no water application), standard high density polyethylene (HDPE) tarp over dry and pre-irrigated soil, virtually impermeable film (VIF) tarp, initial water application by sprinklers immediately following fumigation, and intermittent water applications after fumigation. The atmospheric emissions and gas-phase distribution of fumigants in soil profile were monitored for 9 d. Among the surface seals, VIF and HDPE tarp over dry soil resulted in the lowest and the highest total emission losses, respectively. Intermittent water applications reduced 1,3-D and CP emissions significantly more than HDPE tarp alone. The initial water application also reduced emission peak and delayed emission time. Pre-irrigated soil plus HDPE tarp reduced fumigant emissions similarly as the intermittent water applications and also yielded the highest surface soil temperature, which may improve overall soil pest control. PMID:17215218

Gao, Suduan; Trout, Thomas J

2007-01-01

359

EPA RESEARCH PROGRAM FOR REDUCING CO2 EMISSIONS THROUGH EFFICIENT ENERGY TECHNOLOGIES  

EPA Science Inventory

The paper discusses EPA research in a number of areas that can potentially contribute to the ultimate reduction of global carbon dioxide (CO2) and other greenhouse gas emissions. t provides a brief overview of the major research programs, describing in more detail the development...

360

Process for reducing Ramsbottom Carbon Test of long residues  

SciTech Connect

Process for the preparation of a heavy oil with a low Ramsbottom Carbon Test (RCT) from a long residue by (a) catalytic hydrotreatment for RCT reduction at such severity that the C/sub 4/- gas production per percentage RCT reduction is kept between defined limits, followed by (b) solvent deasphalting of the (vacuum or atmospheric) distillation residue of the hydrotreated product.

Eilers, J.; Stork, W.H.J.

1984-07-17

361

Process and apparatus for reducing pollutant emission in flue gases  

SciTech Connect

This patent describes a combustion process for reducing at least nitrogen oxides, sulfur oxides and hydrogen chloride in a furnace. It comprises introducing a combustible material into a drying zone within a combustion chamber; supplying air to the drying zone for preheating, drying, and partially combusting the combustible material; advancing the combustible material to a combustion zone within the combustion chamber; supplying air to the combustion zone for further combusting the combustible material; advancing the combustible material to a burnout zone within the combustion chamber; supplying air to the burnout zone for final burnout of uncombusted portions of the combustible material; injecting one of a sorbent and a calcined sorbent, and a fuel into the combustion chamber above the combustible material to create an oxygen deficient secondary combustion zone; ejecting vitiated air from the burnout zone; injecting at least one of overfire air and the vitiated air into the combustion chamber above the oxygen deficient secondary combustion zone forming an oxidizing tertiary combustion zone for thorough mixing and final burnout of combustibles in combustion products of the combustible material; and removing ash from the combustion chamber.

Khinkis, M.J.; Patel, J.G.; Rehmat, H.G.

1992-04-21

362

Urban Fluxes Monitoring and Development of Planning Strategies to Reduce Ghg Emissions in AN European City  

NASA Astrophysics Data System (ADS)

Cities and human settlements in general are a primary source of emissions that contribute to human-induced climate change. To investigate the impact of an urbanized area on urban metabolism components, an eddy covariance (EC) tower will be set up in a city (Sassari) located in the center of the Mediterranean basin (Sardinia, Italy). The EC tower, as well as a meteorological station and radiometers, will be set up to monitor energy, water, and carbon fluxes in the city center. A GHG emissions inventory will be also compiled to identify the main emission sources. In addition, a modeling framework will be used to study the impact of different urban planning strategies on carbon emission rates. The modeling framework consists of four models to analyze fluxes both at local and municipality scale: (i) a land surface model ACASA (Advanced Canopy-Atmosphere-Soil Algorithm, ACASA) to simulate the urban metabolism components at local scale; (ii) a Cellular Automata model to simulate the urban land-use dynamics in the near future (20-30 years); (iii) a transportation model to estimate the variation of the transportation network load, and (iv) the coupled model WRF-ACASA will be finally used to simulate the urban metabolism components at municipality scale. The participation of local stakeholders will allow the definition of future planning strategies with the aim to identify low carbon emissions strategies. The projects activities, methodologies applied, as well as the preliminary results will be reported here.

Marras, S.; Sirca, C.; Bellucco, V.; Falk, M.; Pyles, R. D.; Snyder, R. L.; Paw U, K.; Duce, P.; Blecic, I.; Trunfio, G. A.; Cecchini, A.; Spano, D.

2013-12-01

363

Atlas of Halpha emission lines and V light curves of 30 carbon Miras  

Microsoft Academic Search

This paper presents an atlas of V light curves and Halpha emission lines of 30 carbon Miras observed in various photometrical phases. The visualization of both photometric and spectral variations allowed us to reveal a strong correlation between the equivalent widths of the Halpha emission of carbon Miras and their V brightnesses as a function of the photometric phase.

Z. Mikulsek; T. Grf

2005-01-01

364

India's cement industry: Productivity, energy efficiency and carbon emissions  

SciTech Connect

Historical estimates of productivity growth in India's cement sector vary from indicating an improvement to a decline in the sector's productivity. The variance may be traced to the time period of study, source of data for analysis, and type of indices and econometric specifications used for reporting productivity growth. Analysis shows that in the twenty year period, 1973 to 1993, productivity in the aluminum sector increased by 0.8% per annum. An econometric analysis reveals that technical progress in India's cement sector has been biased towards the use of energy and capital, while it has been material and labor saving. The increase in productivity was mainly driven by a period of progress between 1983 and 1991 following partial decontrol of the cement sector in 1982. The authors examine the current changes in structure and energy efficiency in the sector. Their analysis shows that the Indian cement sector is moving towards world-best technology, which will result in fewer carbon emissions and more efficient energy use. However, substantial further energy savings and carbon reduction potentials still exist.

Schumacher, Katja; Sathaye, Jayant

1999-07-01

365

India's aluminum industry: Productivity, energy efficiency and carbon emissions  

SciTech Connect

Historical estimates of productivity growth in India's aluminum sector vary from indicating an improvement to a decline in the sector's productivity. The variance may be traced to the time period of study, source of data for analysis, and type of indices and econometric specifications used for reporting productivity growth. An analysis shows that in the twenty year period, 1973 to 1993, productivity in the aluminum sector declined slightly by 0.2%. An econometric analysis reveals that technical progress in India's aluminum sector has been biased towards the use of energy, while it has been labor saving. The decline in productivity was mainly driven by a decline in the 1970s when capacity utilization was low and the energy crisis hit India and the world. From the early 1980s on productivity recuperated. The authors examine the current changes in structure and energy efficiency in the sector. Their analysis shows that the Indian aluminum sector has high potential to move towards world-best technology, which will result in fewer carbon emissions and more efficient energy use. Substantial energy savings and carbon reduction options exist.

Schumacher, Katja; Sathaye, Jayant

1999-07-01

366

Agriculture, Land Use, Energy and Carbon Emission Impacts of Global Biofuel Mandates to Mid-Century  

SciTech Connect

Three potential future scenarios of expanded global biofuel production are presented here utilizing the GCAM integrated assessment model. These scenarios span a range that encompasses on the low end a continuation of existing biofuel production policies to two scenarios that would require an expansion of current targets as well as an extension of biofuels targets to other regions of the world. Conventional oil use is reduced by 4-8% in the expanded biofuel scenarios, which results in a decrease of in CO2 emissions on the order of 1-2 GtCO2/year by mid-century from the global transportation sector. The regional distribution of crop production is relatively unaffected, but the biofuels targets do result in a marked increase in the production of conventional crops used for energy. Producer prices of sugar and corn reach levels about 12% and 7% above year 2005 levels, while the increased competition for land causes the price of food crops such as wheat, although not used for bioenergy in this study, to increase by 1 to 2%. The amount of land devoted to growing all food crops and dedicated bioenergy crops is increased by about 10% by 2050 in the High biofuel case, with concurrent decreases in other uses of land such as forest and pasture. In both of the expanded biofuels cases studied, there is an increase in net cumulative carbon emissions for the first couple of decades due to these induced land use changes. However, the difference in net cumulative emissions from the biofuels expansion decline by about 2035 as the reductions in energy system emissions exceed further increases in emissions from land use change. Even in the absence of a policy that would limit emissions from land use change, the differences in net cumulative emissions from the biofuels scenarios reach zero by 2050, and are decreasing further over time in both cases.

Wise, Marshall A.; Dooley, James J.; Luckow, Patrick; Calvin, Katherine V.; Kyle, G. Page

2014-02-01

367

Light pollution and solid-state lighting: reducing the carbon dioxide footprint is not enough  

NASA Astrophysics Data System (ADS)

Public and private lighting account for a relevant share of the overall electric power consumption worldwide. The pressing need of reducing the carbon dioxide emissions as well as of lowering the lumenhour price tag has fostered the search for alternative lighting technologies to substitute for the incandescent and gas-discharge based lamps. The most successful approach to date, solid-state lighting, is already finding its way into the public lighting market, very often helped by substantial public investments and support. LED-based sources have distinct advantages: under controlled coditions their efficacy equals or surpasses that of conventional solutions, their small source size allows for an efficient collimation of the lightbeam (delivering the photons where they are actually needed and reducing lightspill on the surrounding areas), and they can be switched and/or dimmed on demand at very high rates, thus allowing for a taylored schedule of lighting. However, energy savings and carbon dioxide reduction are not the only crucial issues faced by present day lighting. A growing body of research has shown the significance of the spectral composition of light when it comes to assess the detrimental effects of artificial light-at-night (ALAN). The potential ALAN blueshift associated to the deployment of LED-based lighting systems has raised sensible concerns about its scientific, cultural, ecological and public health consequences, which can be further amplified if an increased light consumption is produced due to the rebound effect. This contribution addresses some of the challenges that these issues pose to the Optics and Photonics community.

Bar, Salvador

2013-11-01

368

Carbon monoxide signalling reduces photocarcinogenesis in the hairless mouse  

Microsoft Academic Search

Exposure of the skin of mice to UVA (320400nm) radiation has been shown to provide protection against the immunosuppressive\\u000a effects of UVB (290320nm) radiation. The UVA protection was mediated via the UVA induction of the stress protein heme oxygenase-1,\\u000a and its enzymatic product carbon monoxide (CO). Because UVB-induced immunosuppression is an accompanying and prerequisite\\u000a feature of the promotion phase of

Munif Allanson; Vivienne E. Reeve

2007-01-01

369

Process for reducing Ramsbottom Carbon Test of short residues  

SciTech Connect

In the preparation of a heavy oil with a low Ramsbottom Carbon Test (RCT) from a long residue by a two-stage process comprising catalytic hydrotreatment followed by solvent deasphalting and recycle of the asphalt to the first stage the catalytic hydrotreatment for RCT reduction in the first stage is carried out at such a severity that the C/sub 4/ - gas production per percent RCT reduction is kept between defined limits.

Eilers, J.; Stork, H.J.

1984-07-24

370

ESTABLISHING THE LINK BETWEEN AMMONIA EMISSION CONTROL AND MEASUREMENTS OF REDUCED NITROGEN  

E-print Network

ESTABLISHING THE LINK BETWEEN AMMONIA EMISSION CONTROL AND MEASUREMENTS OF REDUCED NITROGEN, Slovakia; 10 Swiss Agency for the Environment, Forest and Landscape (SAEFL), Air Pollution Control Division for some time that the atmospheric transport and deposition of reduced nitrogen (NHx), either as ammonia

Aneja, Viney P.

371

Introduction to NASA contracts. [on engine modifications to reduce exhaust emissions  

NASA Technical Reports Server (NTRS)

The NASA Lewis Research Center issued requests for proposal to Avco Lycoming and Teledyne Continental Motors for a contractual effort to establish and demonstrate engine modifications to reduce exhaust emissions safely with minimum adverse effects on cost, weight, and fuel economy. The secondary objective was reducing fuel consumption.

Kempke, E. E., Jr.

1976-01-01

372

Costs of reducing greenhouse gas emissions in the USA and Canada  

Microsoft Academic Search

A number of possible policy responses can be adopted in order to address the prospect of increasing greenhouse gases in the earth's atmosphere. These include mitigation measures, that reduce greenhouse gas emissions or enhance the processes that remove greenhouse gases from the atmosphere, adaptation measures that reduce the consequences or damages from climate change, and information measures, including scientific research

W David Montgomery

1996-01-01

373

Capture and mineralization of carbon dioxide from coal combustion flue gas emissions  

NASA Astrophysics Data System (ADS)

(Proprietary information: PCT/US/2006/49411 and WO/2007/ 081561A) Enormous amounts of carbon dioxide (CO2) released by human activity (anthropogenic), may lead to climate changes that could spread diseases, ruin crops, cause intense droughts and floods, and dramatically raise the sea levels, thereby submerging the low lying coastal regions. The objective of this study was to test whether CO2 and sulfur dioxide (SO2) from flue gases can be directly captured and converted into carbonate and sulfate minerals respectively through the mineralization process of alkaline solid wastes. A flow-through carbonation process was designed to react flue gases directly with alkaline fly ash, under coal combustion power plant conditions. For the first time, CO2 levels in the flue gas were reduced from 13.6% to 9.7% after the reaction with alkaline fly ash in a reaction time of less than 1 minute. Using a combination of Orion RTM plus multi-gas detector, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) techniques, flue gas CO2 mineralization on fly ash particles was detected. This method can simultaneously help in separate, capture, and mineralize anthropogenic CO2 and SO2. Moreover, this process may be environmentally safe and a stable storage for anthropogenic CO2. Capturing anthropogenic CO2 using this mineralization process is an initial step towards developing more efficient methods of reducing industrial point source CO2 emissions into the atmosphere.

Attili, Viswatej

374

Energy use and carbon dioxide emissions in energy-intensive industries in key developing countries  

SciTech Connect

The industrial sector is the most important end-use sector in developing countries in terms of energy use and was responsible for 50% of primary energy use and 53% of associated carbon dioxide emissions in 1995 (Price et al., 1999). The industrial sector is extremely diverse, encompassing the extraction of natural resources, conversion of these resources into raw materials, and manufacture of finished products. Five energy-intensive industrial subsectors account for the bulk of industrial energy use and related carbon dioxide emissions: iron and steel, chemicals, petroleum refining, pulp and paper, and cement. In this paper, we focus on the steel and cement sectors in Brazil, China, India, and Mexico.1 We review historical trends, noting that China became the world's largest producer of cement in 1985 and of steel in 1996. We discuss trends that influence energy consumption, such as the amount of additives in cement (illustrated through the clinker/cement ratio), the share of electric arc furnaces, and the level of adoption of continuous casting. To gauge the potential for improvement in production of steel and cement in these countries, we calculate a ''best practice'' intensity based on use of international best practice technology to produce the mix of products manufactured in each country in 1995. We show that Brazil has the lowest potential for improvement in both sectors. In contrast, there is significant potential for improvement in Mexico, India, and especially China, where adoption of best practice technologies could reduce energy use and carbon dioxide emissions from steel production by 50% and cement production by 37%. We conclude by comparing the identified potential for energy efficiency improvement and carbon dioxide emissions reduction in these key developing countries to that of the U.S. This comparison raises interesting questions related to efforts to improve energy efficiency in developing countries, such as: what is the appropriate role of industrialized countries in promoting the adoption of low carbon technologies, how do international steel and cement companies influence the situation, and how can such information be used in the context of Clean Development Mechanism in the Kyoto Protocol?

Price, Lynn; Worrell, Ernst; Phylipsen, Dian

1999-09-01

375

Effectiveness of Diesel Oxidation Catalyst in Reducing HC and CO Emissions from Reactivity Controlled Compression Ignition  

SciTech Connect

Reactivity Controlled Compression Ignition (RCCI) has been shown to allow for diesel-like or better brake thermal efficiency with significant reductions in nitrogen oxide (NOX) particulate matter (PM) emissions. Hydrocarbon (HC) and carbon monoxide (CO) emission levels, on the other hand, are similar to those of port fuel injected gasoline engines. The higher HC and CO emissions combined with the lower exhaust temperatures with RCCI operation present a challenge for current exhaust aftertreatments. The reduction of HC and CO emissions in a lean environment is typically achieved with an oxidation catalyst. In this work, several diesel oxidation catalysts (DOC) with different precious metal loadings were evaluated for effectiveness to control HC and CO emissions from RCCI combustion in a light-duty multi-cylinder engine operating on gasoline and diesel fuels. Each catalyst was evaluated in a steady-state engine operation with temperatures ranging from 160 to 260 C. A shift to a higher light-off temperature was observed during the RCCI operation. In addition to the steady-state experiments, the performances of the DOCs were evaluated during multi-mode engine operation by switching from diesel-like combustion at higher exhaust temperature and low HC/CO emissions to RCCI combustion at lower temperature and higher HC/CO emissions. High CO and HC emissions from RCCI generated an exotherm keeping the catalyst above the light-off temperature.

Prikhodko, Vitaly Y [ORNL; Curran, Scott [ORNL; Parks, II, James E [ORNL; Wagner, Robert M [ORNL

2013-01-01

376

High performance bulk metallic glass/carbon nanotube composite cathodes for electron field emission  

SciTech Connect

We report the preparation of new nanocomposites based on a combination of bulk metallic glass and carbon nanotubes for electron field emission applications. The use of bulk metallic glass as the matrix ensures high electrical and thermal conductivity, high thermal stability, and ease of processing, whilst the well dispersed carbon nanotubes act as highly efficient electron emitters. These advantages, alongside excellent electron emission properties, make these composites one of the best reported options for electron emission applications to date.

Hojati-Talemi, Pejman [Department of Materials Engineering, Monash University, Clayton, Vic 3800 (Australia); Mawson Institute, University of South Australia, Mawson Lakes, SA 5095 (Australia); Gibson, Mark A. [Process Science and Engineering, Commonwealth Scientific and Industrial Research Organisation, Clayton, Vic 3168 (Australia); East, Daniel; Simon, George P. [Department of Materials Engineering, Monash University, Clayton, Vic 3800 (Australia)

2011-11-07

377

Modeling Impacts of Management on Carbon Sequestration and Trace Gas Emissions in Forested  

E-print Network

Modeling Impacts of Management on Carbon Sequestration and Trace Gas Emissions in Forested Wetland-DNDC, was modified to enhance its capacity to predict the impacts of management practices on carbon sequestration nonnegligible roles in mitigation in comparison with carbon sequestration. Forests are recognized for having

378

Carbon emissions from cities and urban regions at multiple levels (Invited)  

NASA Astrophysics Data System (ADS)

The role of urban areas in global carbon emissions is expected to be significant and thus crucial for the global climate change mitigation. Accordingly, in this paper, consolidate and present the existing knowledge and information on the urban carbon emissions at global, regional and city levels. This is built on a consolidated knowledge from authors organized and co-edited special issue in Energy Policy Journal titled Carbon Emissions and Carbon Management in Cities published in 2010, other of authors own work in China, Thailand and North-East Asian cities, and the existing literatures on cities. In particular, we present and clarify the contribution of urban areas in the global and respective regional CO2 emissions and the CO2 emissions from the global cities including their inter-comparisons. In those discussions, we present the trends and patterns of CO2 emissions from cities and highlight the points of caution and uncertainties in CO2 estimation imposed by the definitions of urban areas and cities, the scope and approach of estimations, and the methodological limitations. We will pay a special attention to the carbon attribution challenges since urban area is essentially an open system with intense interactions outside its physical boundaries. Their responsibilities for carbon emissions and mitigation vary depending on the choice of the system boundary of urban activities and how carbon emissions are attributed. We show example of such phenomenon quantitatively thorough a case study of Tokyo.

Dhakal, S.

2010-12-01

379

Organically treated biochar increases plant production and reduces N2O emissions: mechanistic insights by 15N tracing  

NASA Astrophysics Data System (ADS)

Pyrogenic carbon (biochar) offers considerable potential for carbon capture and soil storage (CCSS) compared to other, less recalcitrant soil-C additives. Recent meta-analysis demonstrated that it can significantly reduce agricultural N2O emissions. Freshly produced biochars, however, do not always have yield-improving effects, i.e. there is no immediate economic incentive for using it. Hence, combining biochar with organic nutrient-rich amendments may be a promising agricultural strategy to accelerate CCSS, but it is unclear if biochar still reduces N2O emissions, in particular when it may act as nutrient carrier. We explored the potential of biochar to improve the GHG-cost/yield ratio and thereby its socio-economic value as soil amendment in two subsequent studies under controlled conditions: (1) A proof-of-concept study where the effects of untreated biochar were compared to those of co-composted biochar combined with stepwise improved nutritional regimes (+/- compost; +/- mineral-N application), and (2) a 15N-labeling-tracing study to unravel N exchange on biochar particles and N2O production and reduction mechanisms. Both studies were carried out in nutrient-poor sandy soils, the most likely initial target soils for biochar-CCSS strategies. While the untreated biochar reduced plant growth under N-limiting conditions, or at best did not reduce it, the co-composted biochar always significantly stimulated plant growth. The relative stimulation was largest with the lowest nutrient additions (305% versus 61% of control with untreated biochar). Electro-ultra-filtration analyses revealed that the co-composted but not the untreated biochar carried considerable amounts of easily extractable as well as more strongly sorbed plant nutrients, in particular nitrate and phosphorus. The subsequent 15N labelling-tracing study revealed that the co-composted biochar still (i) acted as a mineral-N exchange site for nitrate and ammonium despite its N-preloading, (ii) reduced N2O emissions significantly, although it carried dissolved organic carbon and nitrate as prerequisites for denitrification; and that it thus (iii) significantly improved the GHG-cost/yield ratio of plant production. Our results therefore encourage further investigations on strategies where nutrient-rich agricultural waste streams are combined with biochar post-treatment. Cascading use of biochar in agriculture may have the potential to evolve into a key CCSS technology to turn agriculture from being part of the problem into being part of the solution.

Kammann, Claudia; Messerschmidt, Nicole; Clough, Tim; Schmidt, Hans-Peter; Marhan, Sven; Koyro, Hans-Werner; Steffens, Diedrich; Mller, Christoph

2014-05-01

380

Monsanto: Taking the next environmental step; New technologies are key in reducing emissions  

SciTech Connect

In meeting a 1988 pledge to reduce its worldwide air emissions 90% by the end of 1992, Monsanto completed one of the industry`s most ambitious-and costly-voluntary pollution reduction programs. After $130 million in expenditures and the completion of 250 emission reduction projects, the company had cut its worldwide air emissions 92%, to 5 million lbs, and its U.S. emissions 85%, to 2.7 million lbs. Now Monsanto is looking to take the next step by slashing emission levels of all pollutants. Monsanto has scheduled another round of deadlines that go far beyound regulatory compliance. The company plans on making further reductions, including eliminating the release of waste to underground injection wells, which will likely involve fundamental changes in technology. The company`s goal is to reduce its worldwide toxic chemical releases and transfers to less that 100 million lbs/year by 1995, down 240 million lbs for 1990`s 337 million lbs. Many of Monsanto`s efforts since it made its 1988 pledge have focused on reducing air emissions, because those emissions were the highest. While Monsanto reports about half of its air reductions come from shutdowns of inefficient processes, the 1995 reduction efforts will require increased capital investment for new processes.

Lucas, A.

1994-08-03

381

Changes in Soil Moisture, Microbial Biomass, Mineralization and Nitrification Explain Increases in N2O Emissions from a Spring Barley Crop Under Combined Reduced Tillage and Cover Crop Management  

NASA Astrophysics Data System (ADS)

This study investigated the effect of conventional tillage (CT), combined reduced tillage-cover crop (RT-CC), and reduced N application on crop yield and N2O emissions from spring barley. Reduced tillage plots were established for seven years, the final four incorporating a mustard cover crop. Higher N2O fluxes were from fertilized, RT-CC plots due to higher WFPS, soil nitrate, and soil carbon. Fluxes during the non-growing season were variable and the main source of cumulative emissions. Emission factors were in the range of IPCC default values. Low N fertilization reduced cumulative emissions, however during the wetter growing season this reduction was smaller than the reduction in barley production particular in the conventional tillage plots. Adopting RT-CC management for cereal crops may be problematic in reducing GHG emissions due to high N2O fluxes. Reducing N fertilizer in order to reduce N2O emissions is not feasible due to high inter-annual variation in crop yield. N2O flux in all plots was positively correlated with microbial biomass carbon, net nitrification and mineralization determined in the field. Increased emissions of N2O in the RT-CC plots are accounted for by increases in organic carbon in the soil and increases in mineralization.

Rueangritsarakul, K.; Jones, M.; Roth, B.; Abdalla, M.; Williams, M.

2012-04-01

382

Particulate, Carbon Monoxide, and Acid Emission Factors for Residential Wood Burning Stoves  

Microsoft Academic Search

Emissions from residential wood burning stoves are of Increasing concern in many areas. This concern is due to the magnitude of the emissions and the toxic and chemical characteristics of the pollutants. Recent testing of standard and new technology woodstoves has provided data for developing a family of particulate and carbon monoxide emission factor curves. This testing has also provided

Paul G. Burnet; Norman G. Edmisten; Paul E. Tiegs; James E. Houck; Rachel A. Yoder

1986-01-01

383

Managing soil organic carbon in agriculture: the net effect on greenhouse gas emissions  

Microsoft Academic Search

A change in agricultural practice can increase carbon sequestration in agricultural soils. To know the net effect on greenhouse gas emissions to the atmosphere, however, we consider associated changes in CO2 emissions resulting from the consumption of fossil fuels, emissions of other greenhouse gases and effects on land productivity and crop yield. We also consider how these factors will evolve

Gregg Marland; Tristram O. West; Bernhard Schlamadinger; Lorenza Canella

2003-01-01

384

Black carbon particulate matter emission factors for buoyancy-driven associated gas flares  

Microsoft Academic Search

Flaring is a technique used extensively in the oil and gas industry to burn unwanted flammable gases. Oxidation of the gas can preclude emissions of methane (a potent greenhouse gas); however, flaring creates other pollutant emissions such as particulate matter (PM) in the form of soot or black carbon (BC). Currently available PM emission factors for flares were reviewed and

James D. N. McEwen; Matthew R. Johnson

2012-01-01

385

Exploring the Relationship Between Wetland Methane Emissions and Net Ecosystem Productivity Using Experimental Shading and Labile Carbon Additions.  

NASA Astrophysics Data System (ADS)

Methane (CH4) emissions from wetlands are positively correlated with net ecosystem productivity (NEP); however the relative importance of proposed controlling mechanisms remains poorly understood. The carbon supply hypothesis suggests that recent photosynthesis contributes labile carbon substrate to methanogenic habitats, resulting in higher CH4 emissions with increases in NEP. Plant gas transport is also hypothesized to be important for conducting gases between the soil and the atmosphere. High CH4 production rates often occur in saturated wetland soils where gas diffusion is extremely slow. The aerenchymous tissues of vascular wetland plants can serve as the primary pathway for CH4 emissions from the soil to the atmosphere, while also allowing CH4 to bypass more aerobic soil regions where CH4 oxidation could occur. Using a hypothesis-driven experimental approach, we established shading treatments in a Juncus- dominated wetland in the northern Colorado Front Range, and measured CH4 and CO2 fluxes with a static chamber technique. In the summer of 2007, the shading manipulations (45% and 65% shade) significantly reduced net ecosystem exchange (NEE; an approximation of NEP) and mean CH4 fluxes compared to control plots (p=0.02 and p=0.01, respectively). To test the carbon supply hypothesis, we injected a solution containing acetate (a primary methanogenic carbon source) to a depth of 20cm below the soil surface. Acetate additions stimulated CH4 emission rates across all plots by an average of 29.3% (p=0.01). However the strength of the CH4 emission response was not significantly related to plot treatment or NEE, indicating that reduced carbon supply could not explain the response to shading. We hypothesize that reduced plant gas transport was more important than labile carbon supply for driving the lower CH4 emission rates in shaded plots. The dry weight of above-ground biomass was lower in shaded plots (p=0.04), suggesting a possible link between plant gas transport capacity and the quantity of above-ground tissues. More work is necessary to understand the role of wetland vegetation communities and their gas transport properties as a mechanism to control patterns of CH4 emissions from wetlands.

Owens, S.; von Fischer, J. C.

2007-12-01

386

When big trees fall: Damage and carbon export by reduced impact logging in southern Amazonia  

Microsoft Academic Search

We examined carbon export in whole logs and carbon accumulation as coarse woody debris (CWD) produced from forest damage during all phases of the first and second year of a certified reduced impact logging (RIL) timber harvest in southern Amazonia. Our measurements included a 100% survey of roads and log decks, assessment of canopy damage and ground disturbance in skid

Ted R. Feldpausch; Stefan Jirka; Carlos A. M. Passos; Franklin Jasper; Susan J. Riha

2005-01-01

387

A DRAMATICALLY REDUCED SIZE IN THE GANTRY DESIGN FOR THE PROTON-CARBON THERAPY*  

E-print Network

A DRAMATICALLY REDUCED SIZE IN THE GANTRY DESIGN FOR THE PROTON-CARBON THERAPY* D. Trbojevic, R, LBNL, Berkeley CA, USA Abstract Gantries in the proton/carbon cancer therapy machines represent (FFAG) quarter and half arc beam lines. The gantry is made of combined function magnets with a very

Keil, Eberhard

388

Opportunities to improve energy efficiency and reduce greenhouse gas emissions in the U.S. pulp and paper industry  

SciTech Connect

The pulp and paper industry accounts for over 12% of total manufacturing energy use in the U.S. (U.S. EIA 1997a), contributing 9% to total manufacturing carbon dioxide emissions. In the last twenty-five years primary energy intensity in the pulp and paper industry has declined by an average of 1% per year. However, opportunities still exist to reduce energy use and greenhouse gas emissions in the manufacture of paper in the U.S. This report analyzes the pulp and paper industry (Standard Industrial Code (SIC) 26) and includes a detailed description of the processes involved in the production of paper, providing typical energy use in each process step. We identify over 45 commercially available state-of-the-art technologies and measures to reduce energy use and calculate potential energy savings and carbon dioxide emissions reductions. Given the importance of paper recycling, our analysis examines two cases. Case A identifies potential primary energy savings without accounting for an increase in recycling, while Case B includes increasing paper recycling. In Case B the production volume of pulp is reduced to account for additional pulp recovered from recycling. We use a discount rate of 30% throughout our analysis to reflect the investment decisions taken in a business context. Our Case A results indicate that a total technical potential primary energy savings of 31% (1013 PJ) exists. For case A we identified a cost-effective savings potential of 16% (533 PJ). Carbon dioxide emission reductions from the energy savings in Case A are 25% (7.6 MtC) and 14% (4.4 MtC) for technical and cost-effective potential, respectively. When recycling is included in Case B, overall technical potential energy savings increase to 37% (1215 PJ) while cost-effective energy savings potential is 16%. Increasing paper recycling to high levels (Case B) is nearly cost-effective assuming a cut-off for cost-effectiveness of a simple payback period of 3 years. If this measure is included, then the cost-effective energy savings potential in case B increases to 22%.

Martin, Nathan; Anglani, N.; Einstein, D.; Khrushch, M.; Worrell, E.; Price, L.K.

2000-07-01

389

Opportunities to improve energy efficiency and reduce greenhouse gas emissions in the US pulp and paper industry  

SciTech Connect

The pulp and paper industry accounts for over 12% of total manufacturing energy use in the US (US EIA 1997a), contributing 9% to total manufacturing carbon dioxide emissions. In the last twenty-five years primary energy intensity in the pulp and paper industry has declined by an average of 1% per year. However, opportunities still exist to reduce energy use and greenhouse gas emissions in the manufacture of paper in the US This report analyzes the pulp and paper industry (Standard Industrial Code (SIC) 26) and includes a detailed description of the processes involved in the production of paper, providing typical energy use in each process step. We identify over 45 commercially available state-of-the-art technologies and measures to reduce energy use and calculate potential energy savings and carbon dioxide emissions reductions. Given the importance of paper recycling, our analysis examines two cases. Case A identifies potential primary energy savings without accounting for an increase in recycling, while Case B includes increasing paper recycling. In Case B the production volume of pulp is reduced to account for additional pulp recovered from recycling. We use a discount rate of 30% throughout our analysis to reflect the investment decisions taken in a business context. Our Case A results indicate that a total technical potential primary energy savings of 31% (1013 PJ) exists. For case A we identified a cost-effective savings potential of 16% (533 PJ). Carbon dioxide emission reductions from the energy savings in Case A are 25% (7.6 MtC) and 14% (4.4 MtC) for technical and cost-effective potential, respectively. When recycling is included in Case B, overall technical potential energy savings increase to 37% (1215 PJ) while cost-effective energy savings potential is 16%. Increasing paper recycling to high levels (Case B) is nearly cost-effective assuming a cut-off for cost-effectiveness of a simple payback period of 3 years. If this measure is included, then the cost-effective energy savings potential in case B increases to 22%.

Martin, Nathan; Anglani, N.; Einstein, D.; Khrushch, M.; Worrell, E.; Price, L.K.

2000-07-01

390

Analyzing carbon dioxide and methane emissions in California using airborne measurements and model simulations  

NASA Astrophysics Data System (ADS)

Greenhouse gas (GHG) concentrations have increased over the past decades and are linked to global temperature increases and climate change. These changes in climate have been suggested to have varying effects, and uncertain consequences, on agriculture, water supply, weather, sea-level rise, the economy, and energy. To counteract the trend of increasing atmospheric concentrations of GHGs, the state of California has passed the California Global Warming Act of 2006 (AB-32). This requires that by the year 2020, GHG (e.g., carbon dioxide (CO2) and methane (CH4)) emissions will be reduced to 1990 levels. To quantify GHG fluxes, emission inventories are routinely compiled for the State of California (e.g., CH4 emissions from the California Greenhouse Gas Emissions Measurement (CALGEM) Project). The major sources of CO2 and CH4 in the state of California are: transportation, electricity production, oil and gas extraction, cement plants, agriculture, landfills/waste, livestock, and wetlands. However, uncertainties remain in these emission inventories because many factors contributing to these processes are poorly quantified. To alleviate these uncertainties, a synergistic approach of applying air-borne measurements and chemical transport modeling (CTM) efforts to provide a method of quantifying local and regional GHG emissions will be performed during this study. Additionally, in order to further understand the temporal and spatial distributions of GHG fluxes in California and the impact these species have on regional climate, CTM simulations of daily variations and seasonality of total column CO2 and CH4 will be analyzed. To assess the magnitude and spatial variation of GHG emissions and to identify local 'hot spots', airborne measurements of CH4 and CO2 were made by the Alpha Jet Atmospheric eXperiment (AJAX) over the San Francisco Bay Area (SFBA) and San Joaquin Valley (SJV) in January and February 2013 during the Discover-AQ-CA study. High mixing ratios of GHGs were observed in-flight with a high degree of spatial variability. To provide an additional method to quantify GHG emissions, and analyze AJAX measurement data, the GEOS-Chem CTM is used to simulate SFBA/SJV GHG measurements. A nested-grid version of GEOS-Chem will be applied and utilizes varying emission inventories and model parameterizations to simulate GHG fluxes/emissions. The model considers CO2 fluxes from fossil fuel use, biomass/biofuel burning, terrestrial and oceanic biosphere exchanges, shipping and aviation, and production from the oxidation of carbon monoxide, CH4, and non-methane volatile organic carbons. The major sources of CH4 simulated in GEOS-Chem are domesticated animals, rice fields, natural gas leakage, natural gas venting/flaring (oil production), coal mining, wetlands, and biomass burning. Preliminary results from the comparison between available observations (e.g., AJAX and CALGEM CH4 emission maps) and GEOS-Chem results will be presented, along with a discussion of CO2 and CH4 source apportionment and the use of the GEOS-Chem-adjoint to perform inverse GHG modeling.

Johnson, M. S.; Yates, E. L.; Iraci, L. T.; Jeong, S.; Fischer, M. L.

2013-12-01

391

40 CFR Table N-1 to Subpart N of... - CO2 Emission Factors for Carbonate-Based Raw Materials  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false CO2 Emission Factors for Carbonate-Based Raw... Table N-1 to Subpart N of Part 98CO2 Emission Factors for Carbonate-Based...Carbonate-basedraw materialmineral CO2 emission factor a...

2011-07-01

392

Particulate, carbon monoxide, and acid emission factors for residential wood burn stoves  

SciTech Connect

Emissions from residential wood burning stoves are of increasing concern in many areas. This concern is due to the magnitude of the emissions and the toxic and chemical characteristics of the pollutants. Recent testing of standard and new technology woodstoves has provided data for developing a family of particulate and carbon monoxide emission factor curves. This testing has also provided data illustrating the acidity of woodstove emissions. The particulate and carbon monoxide curves relate the actual stove emissions to the stove size and operating parameters of burn rate, fuel loading, and fuel moisture. Curves relating stove types to the acidity of emissions have also been constructed. Test data show actual emissions vary from 3 to 50 grams per kilogram for particles and from 50 to 300 grams per kilogram for carbon monoxide. Since woodstove emissions are the largest single category of particulate emissions in many area, it is essential that these emissions be quantified specifically for geographic regions, allowing meaningful impact analysis modeling to be accomplished. Emission factors for particles and carbon monoxide are presented from several stove sizes and burn rates. The acidic nature of woodstove emissions has been clearly demonstrated. Tests indicate woodstove flue gas condensate solutions to be predominantly in the 2.8 to 4.2 pH range. Condensate solutions from conventional woodstoves exhibited the characteristic buffering capacity of carboxylic acids when titrations were performed with a strong base. The environmental impact of buffered acidic woodstove emissions is not currently well understood; however, it is possible with the data presented here to make semi-quantitative estimates of acid emission from particulate and carbon monoxide emission factors and wood use inventories.

Burnet, P.G.; Edmisten, N.G.; Tiegs, P.E.; Houck, J.E.; Yoder, R.A.

1986-09-01

393

Increasing leaf temperature reduces the suppression of isoprene emission by elevated CO? concentration.  

PubMed

Including algorithms to account for the suppression of isoprene emission by elevated CO2 concentration affects estimates of global isoprene emission for future climate change scenarios. In this study, leaf-level measurements of isoprene emission were made to determine the short-term interactive effect of leaf temperature and CO2 concentration. For both greenhouse plants and plants grown under field conditions, the suppression of isoprene emission was reduced by increasing leaf temperature. For each of the four different tree species investigated, aspen (Populus tremuloides Michx.), cottonwood (Populus deltoides W. Bartram ex Marshall), red oak (Quercus rubra L.), and tundra dwarf willow (Salix pulchra Cham.), the suppression of isoprene by elevated CO2 was eliminated at increased temperature, and the maximum temperature where suppression was observed ranged from 25 to 35C. Hypotheses proposed to explain the short-term suppression of isoprene emission by increased CO2 concentration were tested against this observation. Hypotheses related to cofactors in the methylerythritol phosphate (MEP) pathway were consistent with reduced suppression at elevated leaf temperature. Also, reduced solubility of CO2 with increased temperature can explain the reduced suppression for the phosphoenolpyruvate (PEP) carboxylase competition hypothesis. Some global models of isoprene emission include the short-term suppression effect, and should be modified to include the observed interaction. If these results are consistent at longer timescales, there are implications for predicting future global isoprene emission budgets and the reduced suppression at increased temperature could explain some of the variable responses observed in long-term CO2 exposure experiments. PMID:24614154

Potosnak, Mark J; Lestourgeon, Lauren; Nunez, Othon

2014-05-15

394

40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.  

Code of Federal Regulations, 2013 CFR

...false Oxides of nitrogen, carbon monoxide, hydrocarbon, and...112 Oxides of nitrogen, carbon monoxide, hydrocarbon, and...emissions of oxides of nitrogen, carbon monoxide, hydrocarbon, and...Heavy-Duty Off-Road Diesel Cycle Engines. This procedure is...

2013-07-01

395

40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.  

Code of Federal Regulations, 2012 CFR

...false Oxides of nitrogen, carbon monoxide, hydrocarbon, and...112 Oxides of nitrogen, carbon monoxide, hydrocarbon, and...emissions of oxides of nitrogen, carbon monoxide, hydrocarbon, and...Heavy-Duty Off-Road Diesel Cycle Engines. This procedure is...

2012-07-01

396

40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.  

Code of Federal Regulations, 2010 CFR

...false Oxides of nitrogen, carbon monoxide, hydrocarbon, and...112 Oxides of nitrogen, carbon monoxide, hydrocarbon, and...emissions of oxides of nitrogen, carbon monoxide, hydrocarbon, and...Heavy-Duty Off-Road Diesel Cycle Engines. This procedure is...

2010-07-01

397

40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.  

Code of Federal Regulations, 2011 CFR

...false Oxides of nitrogen, carbon monoxide, hydrocarbon, and...112 Oxides of nitrogen, carbon monoxide, hydrocarbon, and...emissions of oxides of nitrogen, carbon monoxide, hydrocarbon, and...Heavy-Duty Off-Road Diesel Cycle Engines. This procedure is...

2011-07-01

398

40 CFR 89.112 - Oxides of nitrogen, carbon monoxide, hydrocarbon, and particulate matter exhaust emission standards.  

Code of Federal Regulations, 2014 CFR

... true Oxides of nitrogen, carbon monoxide, hydrocarbon, and...112 Oxides of nitrogen, carbon monoxide, hydrocarbon, and...emissions of oxides of nitrogen, carbon monoxide, hydrocarbon, and...Heavy-Duty Off-Road Diesel Cycle Engines. This procedure is...

2014-07-01

399

A Global Emission Inventory of Black Carbon and Primary Organic Carbon from Fossil-Fuel and Biofuel Combustion  

NASA Astrophysics Data System (ADS)

Regional and global climate models rely on emission inventories of black carbon and organic carbon to determine the climatic effects of primary particulate matter (PM) from combustion. The emission of primary carbonaceous particles is highly dependent on fuel type and combustion practice. Therefore, simple categories such as "domestic" or "industrial" combustion are not sufficient to quantify emissions, and the black-carbon and organic-carbon fractions of PM vary with combustion type. We present a global inventory of primary carbonaceous particles that improves on previous "bottom-up" tabulations (e.g. \\textit{Cooke et al.,} 1999) by considering approximately 100 technologies, each representing one combination of fuel, combustion type, and emission controls. For fossil-fuel combustion, we include several categories not found in previous inventories, including "superemitting" and two-stroke vehicles, steel-making. We also include emissions from waste burning and biofuels used for heating and cooking. Open biomass burning is not included. Fuel use, drawn from International Energy Agency (IEA) and United Nations (UN) data, is divided into technologies on a regional basis. We suggest that emissions in developing countries are better characterized by including high-emitting technologies than by invoking emission multipliers. Due to lack of information on emission factors and technologies in use, uncertainties are high. We estimate central values and uncertainties by combining the range of emission factors found in the literature with reasonable estimates of technology divisions. We provide regional totals of central, low and high estimates, identify the sources of greatest uncertainty to be targeted for future work, and compare our results with previous emission inventories. Both central estimates and uncertainties are given on a 1\\deg x1\\deg grid. As we have reported previously for the case of China (\\textit{Streets et al.,} 2001), low-technology combustion contributes greatly to the emissions and to the uncertainties.

Bond, T. C.; Streets, D. G.; Nelson, S. M.

2001-12-01

400

Field emission effects of nitrogenated carbon nanotubes on chlorination and oxidation  

SciTech Connect

With reference to our recent reports [Appl. Phys. Lett. 90, 192107 (2007); Appl. Phys. Lett. 91, 202102 (2007)] about the electronic structure of chlorine treated and oxygen-plasma treated nitrogenated carbon nanotubes (N-CNTs), here we studied the electron field emission effects on chlorination (N-CNT:Cl) and oxidation (N-CNT:O) of N-CNT. A high current density (J) of 15.0 mA/cm{sup 2} has been achieved on chlorination, whereas low J of 0.0052 mA/cm{sup 2} is observed on oxidation compared to J=1.3 mA/cm{sup 2} for untreated N-CNT at an applied electric field E{sub A} of {approx}1.9 V/{mu}m. The turn-on electric field (E{sub TO}) was {approx}0.875. The 1.25 V/{mu}m was achieved for N-CNT:Cl and N-CNT:O, respectively, with respect to E{sub TO}=1.0 V/{mu}m for untreated one. These findings are due to the formation of different bonds with carbon and nitrogen in the N-CNT during the process of chlorine (oxygen)-plasma treatment by the charge transfer, or else that changes the density of free charge carriers and hence enhances (reduces) the field emission properties of N-CNTs:Cl (N-CNTs:O)

Ray, S. C.; Palnitkar, U.; Pao, C. W.; Tsai, H. M.; Pong, W. F.; Lin, I-N. [Department of Physics, Tamkang University, Tamsui 251, Taiwan (China); Papakonstantinou, P. [NRI, School of Electrical and Mechanical Engineering, University of Ulster at Jordanstown, Newtownabbey, County Antrim BT37OQB, Northern Ireland (United Kingdom); Ganguly, Abhijit; Chen, L. C. [Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan (China); Chen, K. H. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China)

2008-09-15

401

Method of depositing multi-layer carbon-based coatings for field emission  

DOEpatents

A novel field emitter device for cold cathode field emission applications, comprising a multi-layer resistive carbon film. The multi-layered film of the present invention is comprised of at least two layers of a resistive carbon material, preferably amorphous-tetrahedrally coordinated carbon, such that the resistivities of adjacent layers differ. For electron emission from the surface, the preferred structure comprises a top layer having a lower resistivity than the bottom layer. For edge emitting structures, the preferred structure of the film comprises a plurality of carbon layers, wherein adjacent layers have different resistivities. Through selection of deposition conditions, including the energy of the depositing carbon species, the presence or absence of certain elements such as H, N, inert gases or boron, carbon layers having desired resistivities can be produced. Field emitters made according the present invention display improved electron emission characteristics in comparison to conventional field emitter materials.

Sullivan, John P. (Albuquerque, NM); Friedmann, Thomas A. (Albuquerque, NM)

1999-01-01

402

Method of depositing multi-layer carbon-based coatings for field emission  

DOEpatents

A novel field emitter device is disclosed for cold cathode field emission applications, comprising a multi-layer resistive carbon film. The multi-layered film of the present invention is comprised of at least two layers of a resistive carbon material, preferably amorphous-tetrahedrally coordinated carbon, such that the resistivities of adjacent layers differ. For electron emission from the surface, the preferred structure comprises a top