Can savannas help balance the South African greenhouse gas budget?

CSIR Research Space (South Africa)

Scholes, RJ

1996-02-01

Full Text Available This article discusses the South African Greenhouse Experiment on Savannas (SAGES) study conducted by the CSIR' Division of Forest Science and Technology (Foretek) on the role of savannas in the balance of the greenhouse gas budget of South Africa...

Reconstruction of specific mass balance for glaciers in Western ...

Indian Academy of Sciences (India)

Vinay Kumar Gaddam

2017-06-12

Jun 12, 2017 ... temperatures and precipitation estimates of ERA 20CM ensemble climate reanalysis datasets to reconstruct the specific mass balance for a period of 110 years, between 1900 and 2010. Mass balance estimates suggest that the Shaune Garang, Gor-Garang and Gara glaciers have experienced both ...

Towards a standard methodology for greenhouse gas balances of bioenergy systems in comparison with fossil energy systems

International Nuclear Information System (INIS)

Schlamadinger, B.; Jungmeier, G.; Apps, M.; Bohlin, F.; Gustavsson, L.; Marland, G.; Pingoud, K.; Savolainen, I.

1997-01-01

In this paper, which was prepared as part of IEA Bioenergy Task XV (''Greenhouse Gas Balances of Bioenergy Systems''), we outline a standard methodology for comparing the greenhouse gas balances of bioenergy systems with those of fossil energy systems. Emphasis is on a careful definition of system boundaries. The following issues are dealt with in detail: time interval analysed and changes of carbon stocks; reference energy systems; energy inputs required to produce, process and transport fuels; mass and energy losses along the entire fuel chain; energy embodied in facility infrastructure; distribution systems; cogeneration systems; by-products; waste wood and other biomass waste for energy; reference land use; and other environmental issues. For each of these areas recommendations are given on how analyses of greenhouse gas balances should be performed. In some cases we also point out alternative ways of doing the greenhouse gas accounting. Finally, the paper gives some recommendations on how bioenergy systems should be optimized from a greenhouse-gas emissions point of view. (author)

An energy balance and greenhouse gas profile for county Wexford, Ireland in 2006

International Nuclear Information System (INIS)

Curtin, Richard

2011-01-01

Highlights: → Residential sector emits 38% of total CO 2 emissions. → Transport and industry/commerce sectors emit 28% each. → Oil composes 91% of total primary energy requirement (TPER). → Methane accounts for 25% of total greenhouse gas emissions. → Agriculture accounts for 36% of total greenhouse gas emissions. -- Abstract: In this paper an energy balance and a greenhouse gas profile has been formulated for the county of Wexford, situated in the south east of Ireland. The energy balance aims to aggregate all energy consumption in the county for the year 2006 across the following sectors; residential, agriculture, commerce and industry, and transport. The results of the energy balance are compared with the previous energy balance of 2001 where it is found that the residential sector is the biggest emitter of CO 2 with 38% of total emissions with the transport and industry/commerce sectors sharing second place on 28%. Consumption of oil is seen to have increased significantly in nearly all sectors, accounting for over 70% of the total final energy consumed (TFC) while the total primary energy requirement (TPER) sees oil consumption accounting for 91% of all fuels consumed. To take into account the contribution of agriculture in total GHG emissions the gases CH 4 and N 2 O will be estimated from the agricultural and waste sectors. The results show that methane contributes 25% of total GHG emissions with agriculture being the primary contributor accounting for 36% of total emissions.

The role of peat in finnish greenhouse gas balances

International Nuclear Information System (INIS)

Crill, P.; Hargreaves, K.; Korhola, A.

2000-06-01

Over the past, total annual greenhouse gas (GHG) emissions from Finland, not considering land use change, forestry or peatlands, have remained between 70 000 and 80 000 Gg of CO 2 equivalents. A large portion of which (84% in 1998) is from energy and energy related sources. Signatory members to the 1997 Kyoto protocol of the United Nation's Framework Convention on Climate Change convention, which includes Finland, are compelled to assess their emissions at the national level. This study was undertaken to examine the issues of the role of Finnish peatlands in the national greenhouse gas inventory specifically within the context of the utilization of peatlands for energy production. Our analysis is essentially a literature review and assessment of what has been measured from Finnish peatlands. We are particularly fortunate that there have been a series of recent Ph.D. theses published at the Universities of Helsinki and Joensuu and graduate work at the University of Kuopio on carbon dynamics and greenhouse gas exchange in Finnish peatlands that have both expanded our database and our understanding of peatland processes. Chapter 1 provides a background of the role of peatlands in carbon cycling within the context of changing climate and land use. In Finland about 56 x 103 ha of peatland area were being harvested in 1997, 94% for energy. Even though this is a relatively small area, the implications, on a national scale, for GHG fluxes and carbon balance can be significant The magnitude of GHG fluxes and a qualitative assessment of extant data quality and quantity under different Finnish land use forms and activities is considered in chapter 2. CO 2 fluxes derived from long term C accumulation rates indicate that 3 010 Gg CON and 9 400 Gg CO 2 are sequestered annually from the atmosphere into undrained and peatlands drained for forestry, respectively. Peatlands drained for agriculture emit CO 2 at a rate of 3 200-7 800 Gg annually. Peat harvesting activities and

Ownership, allocating and balancing issues for natural gas in the common stream

International Nuclear Information System (INIS)

Onn, W.D.

1997-01-01

The contentious issues of ownership, allocation and balancing of natural gas in the common stream were discussed. The potential influence of recent developments such as the construction of new pipelines, the NCL/Solex dispute at Taylor, B.C., and the political and regulatory responses to these developments were cited as examples of how the issues could be resolved. Currently some 80 per cent of Canada's natural gas production is transported by the Nova Pipeline System, a system comprising 21,700 km of pipeline, 938 receipt and 166 delivery points in Alberta. Gas in the system is co-mingled and receipts and deliveries are balanced on an energy basis. Agreements currently in place do not provide for recognizing the added value of natural gas liquid (NGL) components. It is believed that increased NGL value can only be provided by modification of the current system. Key elements in modifying the system were discussed at some length. These include component tracking, ownership and control of NGL by producer or shippers on the Nova System, and the role of straddle plants in a modified system. Various scenarios, some including participation of straddle plants, others that do not include them, have been proposed. The position of stake holders and other implications of the suggested changes to the current system were also reviewed

Particular cases of materials balance equation generalized for gas deposits associated to the coal

International Nuclear Information System (INIS)

Penuela, G; Ordonez, A; Bejarano, A

1997-01-01

One of the fundamental principles used in the work, developed in engineering is the law of the matter conservation. The application of this principle to the hydrocarbons fields, with the purpose of to quantify and to be predicted expresses by means of materials balance method. While the equation construction of conventional materials balance and the calculations that come with their application are not a difficult task, the approach of selection of the solution that better it represents the deposit it is one of the problems that the petroleum engineer should face. The materials balance is a useful analysis method of the deposit operation, reserves estimate of raw and gas, and prediction of the future behavior of the deposit. The coal, beds, devonian shales and geo pressurized-aquifer are some examples of natural gas sources and to possess production mechanisms and behaviors significantly different to the traditional than have been considered as non conventional deposits

Energy balance of a laser ablation plume expanding in a background gas

DEFF Research Database (Denmark)

Amoruso, Salvatore; Schou, Jørgen; Lunney, James G.

2010-01-01

The energy balance of a laser ablation plume in an ambient gas for nanosecond pulses has been investigated on the basis of the model of Predtechensky and Mayorov (PM), which provides a relatively simple and clear description of the essential hydrodynamics. This approach also leads to an insightfu...

Diurnal Variation in Gas Exchange: The Balance between Carbon Fixation and Water Loss.

Science.gov (United States)

Matthews, Jack S A; Vialet-Chabrand, Silvere R M; Lawson, Tracy

2017-06-01

Stomatal control of transpiration is critical for maintaining important processes, such as plant water status, leaf temperature, as well as permitting sufficient CO 2 diffusion into the leaf to maintain photosynthetic rates ( A ). Stomatal conductance often closely correlates with A and is thought to control the balance between water loss and carbon gain. It has been suggested that a mesophyll-driven signal coordinates A and stomatal conductance responses to maintain this relationship; however, the signal has yet to be fully elucidated. Despite this correlation under stable environmental conditions, the responses of both parameters vary spatially and temporally and are dependent on species, environment, and plant water status. Most current models neglect these aspects of gas exchange, although it is clear that they play a vital role in the balance of carbon fixation and water loss. Future efforts should consider the dynamic nature of whole-plant gas exchange and how it represents much more than the sum of its individual leaf-level components, and they should take into consideration the long-term effect on gas exchange over time. © 2017 American Society of Plant Biologists. All Rights Reserved.

Reconstruction of specific mass balance for glaciers in Western ...

Indian Academy of Sciences (India)

Seasonal sensitivity characteristics (SSCs) were developed for Naradu, Shaune Garang, Gor Garang and Gara glaciers, Western Himalaya to quantify the changes in mean specific mass balance using monthly temperature and precipitation perturbations. The temperature sensitivities were observed high during summer ...

Layer-specific excitation/inhibition balances during neuronal synchronization in the visual cortex.

Science.gov (United States)

Adesnik, Hillel

2018-05-01

Understanding the balance between synaptic excitation and inhibition in cortical circuits in the brain, and how this contributes to cortical rhythms, is fundamental to explaining information processing in the cortex. This study used cortical layer-specific optogenetic activation in mouse cortex to show that excitatory neurons in any cortical layer can drive powerful gamma rhythms, while inhibition balances excitation. The net impact of this is to keep activity within each layer in check, but simultaneously to promote the propagation of activity to downstream layers. The data show that rhythm-generating circuits exist in all principle layers of the cortex, and provide layer-specific balances of excitation and inhibition that affect the flow of information across the layers. Rhythmic activity can synchronize neural ensembles within and across cortical layers. While gamma band rhythmicity has been observed in all layers, the laminar sources and functional impacts of neuronal synchronization in the cortex remain incompletely understood. Here, layer-specific optogenetic stimulation demonstrates that populations of excitatory neurons in any cortical layer of the mouse's primary visual cortex are sufficient to powerfully entrain neuronal oscillations in the gamma band. Within each layer, inhibition balances excitation and keeps activity in check. Across layers, translaminar output overcomes inhibition and drives downstream firing. These data establish that rhythm-generating circuits exist in all principle layers of the cortex, but provide layer-specific balances of excitation and inhibition that may dynamically shape the flow of information through cortical circuits. These data might help explain how excitation/inhibition (E/I) balances across cortical layers shape information processing, and shed light on the diverse nature and functional impacts of cortical gamma rhythms. © 2018 The Authors. The Journal of Physiology © 2018 The Physiological Society.

A Greenhouse Gas Balance of Electricity Production from Co-firing Palm Oil Products from Malaysia

International Nuclear Information System (INIS)

Wicke, B.; Dornburg, V.; Faaij, A.; Junginger, M.

2007-05-01

The Netherlands imports significant quantities of biomass for energy production, among which palm oil has been used increasingly for co-firing in existing gas-fired power plants for renewable electricity production. Imported biomass, however, can not simply be considered a sustainable energy source. The production and removal of biomass in other places in the world result in ecological, land-use and socio-economic impacts and in GHG emissions (e.g. for transportation). As a result of the sustainability discussions, the Cramer Commission in the Netherlands has formulated (draft) criteria and indicators for sustainable biomass production. This study develops a detailed methodology for determining the GHG balance of co-firing palm oil products in the Netherlands based on the Cramer Commission methodology. The methodology is applied to a specific bio-electricity chain: the production of palm oil and a palm oil derivative, palm fatty acid distillate (PFAD), in Northeast Borneo in Malaysia, their transport to the Netherlands and co-firing with natural gas for electricity production at the Essent Claus power plant

Greenhouse gas emissions and energy balance of palm oil biofuel

Energy Technology Data Exchange (ETDEWEB)

de Souza, Simone Pereira; Pacca, Sergio [Graduate Program on Environmental Engineering Science, School of Engineering of Sao Carlos, University of Sao Paulo, Rua Arlindo Bettio, 1000 Sao Paulo (Brazil); de Avila, Marcio Turra; Borges, Jose Luiz B. [Brazilian Agricultural Research Corporation (Embrapa - Soja) (Brazil)

2010-11-15

The search for alternatives to fossil fuels is boosting interest in biodiesel production. Among the crops used to produce biodiesel, palm trees stand out due to their high productivity and positive energy balance. This work assesses life cycle emissions and the energy balance of biodiesel production from palm oil in Brazil. The results are compared through a meta-analysis to previous published studies: Wood and Corley (1991) [Wood BJ, Corley RH. The energy balance of oil palm cultivation. In: PORIM intl. palm oil conference - agriculture; 1991.], Malaysia; Yusoff and Hansen (2005) [Yusoff S, Hansen SB. Feasibility study of performing an life cycle assessment on crude palm oil production in Malaysia. International Journal of Life Cycle Assessment 2007;12:50-8], Malaysia; Angarita et al. (2009) [Angarita EE, Lora EE, Costa RE, Torres EA. The energy balance in the palm oil-derived methyl ester (PME) life cycle for the cases in Brazil and Colombia. Renewable Energy 2009;34:2905-13], Colombia; Pleanjai and Gheewala (2009) [Pleanjai S, Gheewala SH. Full chain energy analysis of biodiesel production from palm oil in Thailand. Applied Energy 2009;86:S209-14], Thailand; and Yee et al. (2009) [Yee KF, Tan KT, Abdullah AZ, Lee KT. Life cycle assessment of palm biodiesel: revealing facts and benefits for sustainability. Applied Energy 2009;86:S189-96], Malaysia. In our study, data for the agricultural phase, transport, and energy content of the products and co-products were obtained from previous assessments done in Brazil. The energy intensities and greenhouse gas emission factors were obtained from the Simapro 7.1.8. software and other authors. These factors were applied to the inputs and outputs listed in the selected studies to render them comparable. The energy balance for our study was 1:5.37. In comparison the range for the other studies is between 1:3.40 and 1:7.78. Life cycle emissions determined in our assessment resulted in 1437 kg CO{sub 2}e/ha, while our analysis

Estimation of air-water gas exchange coefficient in a shallow lagoon based on 222Rn mass balance.

Science.gov (United States)

Cockenpot, S; Claude, C; Radakovitch, O

2015-05-01

The radon-222 mass balance is now commonly used to quantify water fluxes due to Submarine Groundwater Discharge (SGD) in coastal areas. One of the main loss terms of this mass balance, the radon evasion to the atmosphere, is based on empirical equations. This term is generally estimated using one among the many empirical equations describing the gas transfer velocity as a function of wind speed that have been proposed in the literature. These equations were, however, mainly obtained from areas of deep water and may be less appropriate for shallow areas. Here, we calculate the radon mass balance for a windy shallow coastal lagoon (mean depth of 6m and surface area of 1.55*10(8) m(2)) and use these data to estimate the radon loss to the atmosphere and the corresponding gas transfer velocity. We present new equations, adapted to our shallow water body, to express the gas transfer velocity as a function of wind speed at 10 m height (wind range from 2 to 12.5 m/s). When compared with those from the literature, these equations fit particularly well with the one of Kremer et al. (2003). Finally, we emphasize that some gas transfer exchange may always occur, even for conditions without wind. Copyright © 2015 Elsevier Ltd. All rights reserved.

Natural gas energy efficiency potential: assessment of useful energy balance and opportunities for ESCOs in Brazil; Potencial de eficiencia energetica para gas natural: analise do balanco de energia util e oportunidades para ESCOs (Empresas de Servico de Conservacao de Energia) no Brasil

Energy Technology Data Exchange (ETDEWEB)

Aragao Neto, Raymundo Moniz de [Empresa de Pesquisa Energetica (EPE), Rio de Janeiro, RJ (Brazil)

2008-07-01

The market for ESCOs in Brazil has a great opportunity, by offering energy efficiency services related to natural gas use. The article presents a revision of ESCO concept and analyses the market potential for this specific segment, based upon data from the Useful Energy Balance. (author)

Growth arrest specific protein (GAS) 6

DEFF Research Database (Denmark)

Haase, T N; Rasmussen, Morten; Jaksch, C A M

2013-01-01

using RNA microarray and quantitative PCR. The role of a differentially expressed gene, growth arrest specific protein 6 (GAS6), was evaluated in vitro using neonatal rat islets. Results The mRNA level of Gas6, known to be mitogenic in other tissues, was reduced in LP offspring. The mRNA content of Mafa...... was increased in LP offspring suggesting an early maturation of beta cells. When applied in vitro, GAS6 increased proliferation of neonatal pancreatic beta cells, while reducing glucose-stimulated insulin secretion without changing the total insulin content of the islets. In addition, GAS6 decreased the m......RNA content of Mafa. Conclusions/interpretation We propose a role for GAS6 in the regulation of pancreatic beta cells in the critical period around the time of birth. Our results support the hypothesis that the reduced beta cell mass seen in LP offspring is caused by a change in the intra-uterine environment...

A multi-level simulation platform of natural gas internal reforming solid oxide fuel cell-gas turbine hybrid generation system - Part II. Balancing units model library and system simulation

Science.gov (United States)

Bao, Cheng; Cai, Ningsheng; Croiset, Eric

2011-10-01

Following our integrated hierarchical modeling framework of natural gas internal reforming solid oxide fuel cell (IRSOFC), this paper firstly introduces the model libraries of main balancing units, including some state-of-the-art achievements and our specific work. Based on gPROMS programming code, flexible configuration and modular design are fully realized by specifying graphically all unit models in each level. Via comparison with the steady-state experimental data of Siemens-Westinghouse demonstration system, the in-house multi-level SOFC-gas turbine (GT) simulation platform is validated to be more accurate than the advanced power system analysis tool (APSAT). Moreover, some units of the demonstration system are designed reversely for analysis of a typically part-load transient process. The framework of distributed and dynamic modeling in most of units is significant for the development of control strategies in the future.

Savings on natural gas consumption by doubling thermal efficiencies of balanced-flue space heaters

Energy Technology Data Exchange (ETDEWEB)

Juanico, Luis E. [Conicet, and Centro Atomico Bariloche e Instituto Balseiro, Av. Bustillo 9500, 8400 Bariloche, Rio Negro (Argentina); Gonzalez, Alejandro D. [Grupo de Estudios Ambientales, Instituto de Investigaciones en Biodiversidad y Medio Ambiente (Inibioma-Conicet), 8400 Bariloche, Rio Negro (Argentina)

2008-07-01

Natural gas is a relatively clean fossil fuel for space heating. However, when it is not used efficiently high consumption can become an environmental problem. In Argentina, individual balanced-flue space heaters are the most extensively used in temperate and cold regions. This furnace is a simple device with a burner set into a metal chamber, separated from the indoor ambient by an enclosing cabinet, and both inlet and outgas chimneys are connected to the outdoor ambient. In previous studies, we measured the performance of these commercial devices, and found very low thermal efficiency (in the range of 39-63% depending on the chimney configuration). The extensive use of these devices is possible due to the availability of unlimited amount of subsidised natural gas to households and businesses. In the present work, we developed a prototype with simple and low cost modifications made on commercial models, and measured the improvements on the thermal efficiency. Findings showed better infrared radiation, enhanced indoor air convection, and passive chimney flow regulation leading to thermal efficiency in the range of 75-85%. These values represent an improvement of 100% when compared to marketed models, and hence, the specific cost of the heater per unit of useful heating power delivered was actually reduced. Considering the large market presence of these furnaces in both residential and business sectors in Argentina, the potential benefits related to gas consumption and environmental emissions are very significant. (author)

Balance of plan gas

International Nuclear Information System (INIS)

1997-01-01

An increment of 10% is observed, in the supply of the gas propane in 1996 being generated big expectations in the initiation of the Natural Gas program, these achievements in those that comes participating the private sector actively, have given to the plan gas a dynamics peculiar to the investments fundamentally in the exploration areas, production, transport and distribution, being configured in the country a transition phase for the use of this resource, characterized by the change from a state manager to a state regulator that even reflective holes and serious focus problems to allow a competitive handling of this industry. With the entrance in operation of the new platform in the Guajira at the end of 1998 and the production expectations in the opon Area, the possibilities are increased of gas supply for the short term, however in the medium and long term they think about queries before the uncertainty and opportune exploitation of the gas in the piedemonte llanero areas, for the recruiting problems that it is trusted, they will be overcome for benefit of the parts, with all the volume of proven and probable reserves of gas it shows a readiness for 35 years if they stay the production levels and it demands

Future arrangements for Great Britain's gas quality specifications. Government Response (including Summary of Responses) to consultation on future arrangements for Great Britain's gas quality specifications

International Nuclear Information System (INIS)

2007-01-01

Last year the Government consulted on GB's future gas quality specifications. The background is that some streams of imported gases have an energy content that exceeds the upper limit specified in GB's current gas quality regulations. The policy issue was whether to stick with the current regulated specifications, but at the cost of having to process imported gas to bring it within those specifications; or, at some time after 2020, to adjust those specifications, but at the cost of having to check (and potentially change) approximately 45m domestic gas appliances in 22m households, to ensure that they are capable of burning the high energy gas safely (and with a residual safety risk that some appliances are missed). The Consultation Document sought views on the proposal (backed up by the Partial Regulatory Impact Assessment) to adopt the 'no change' option. In the light of the responses, this is what the Government now proposes. The associated Impact Assessment estimates the total net benefit of the 'no change' option at UK Pounds 1.5bn - 14bn, with a best estimate of UK Pounds 8bn (NPV, 2005). The risks for gas prices and security of supply (included in the Impact Assessment) are judged to be small. The Government proposes a 'forward plan', consisting of support for Ofgem's work on maximising the commercial flexibilities for the GB gas market to handle gases of different specifications, whilst continuing to engage in EU discussions on the gas quality issue. (Author)

Sensory-specific balance training in older adults: effect on proprioceptive reintegration and cognitive demands.

Science.gov (United States)

Westlake, Kelly P; Culham, Elsie G

2007-10-01

Age-related changes in the ability to adjust to alterations in sensory information contribute to impaired postural stability. The purpose of this randomized controlled trial was to investigate the effect of sensory-specific balance training on proprioceptive reintegration. The subjects of this study were 36 older participants who were healthy. Participants were randomly assigned to a balance exercise group (n=17) or a falls prevention education group (n=19). The primary outcome measure was the center-of-pressure (COP) velocity change score. This score represented the difference between COP velocity over 45 seconds of quiet standing and each of six 5-second intervals following proprioceptive perturbation through vibration with or without a secondary cognitive task. Clinical outcome measures included the Fullerton Advanced Balance (FAB) Scale and the Activities-specific Balance Confidence (ABC) Scale. Assessments were conducted at baseline, postintervention, and at an 8-week follow-up. Following the exercise intervention, there was less destabilization within the first 5 seconds following vibration with or without a secondary task than there was at baseline or in the falls prevention education group. These training effects were not maintained at the 8-week follow-up. Postintervention improvements also were seen on the FAB Scale and were maintained at follow-up. No changes in ABC Scale scores were identified in the balance exercise group, but ABC Scale scores indicated reduced balance confidence in the falls prevention education group postintervention. The results of this study support short-term enhanced postural responses to proprioceptive reintegration following a sensory-specific balance exercise program.

THE EFFECTIVENESS OF SPORTS SPECIFIC BALANCE TRAINING PROGRAM IN REDUCING RISK OF ANKLE SPRAIN IN BASKETBALL

Directory of Open Access Journals (Sweden)

Ai Choo LEE

2016-12-01

Full Text Available Background: To investigate the effectiveness of four weeks sports specific balance training program to improve balance, thus reducing the risk of ankle sprain among Sultan Idris Education University basketball players. Method: There were 20 males basketball players (aged 19-24 years volunteered in this study. After screening process, there were14 male players met the inclusion criteria. They were randomized into two groups i.e experimental group (EG: n=7 and control group (CG: n=7. The EG undergone the four weeks sports specific balance training program three times per week while the CG followed their normal standard basketball training program. Balance Error Scoring System (BESS was used to assess static balance while Star Excursion Balance Test (SEBT is utilized to examine the dynamic balance. Pretest and posttest of balance measures were recorded using BESS and SEBT for both EG and CG. The data were analyzed using independent sample t-test (p=0.05. Results: The study findings indicated that there were significant differences between EG and CG for the static balance on firm surface (t=-4.642, p=0.001 and on foam surface (t=-8.590, P=0.000 as well as dynamic balance on left leg stance (t=2.350, P=0.037 and on right leg stance (t=3.145, P=0.008. Conclusion: The study findings indicated that the four weeks sports specific balance training program could improve balance ability in male basketball players, thus may reducing the risk of ankle sprain.

Carbon stocks and greenhouse gas balance of an old-growth forest and an anthropogenic peatland in southern Chile

Science.gov (United States)

Perez-Quezada, J. F.; Brito, C. E.; Valdés, A.; Urrutia, P.

2016-12-01

Few studies have reported the effects of deforestation on carbon stocks and greenhouse gas balance in the temperate forests of the southern hemisphere. In some areas of southern Chile, after clear-cut or forest fires occurs a proliferation of Sphagnum moss, generating an anthropogenic type of peatland. We measured the effects of this change on the carbon stocks and the greenhouse gas balance, starting in 2013. Carbon stocks were measured in >30 plots on each site; ecosystem CO2 fluxes were measured continuously using eddy covariance stations; CH4 and N2O fluxes were measured monthly using closed chambers and cavity ring-down spectroscopy technology. Total ecosystem carbon stock was 1,523 Mg ha-1 in the forest and 130 Mg ha-1 in the peatland, representing a 91% difference. Both land use types were found to act as sinks of CO2 (NEE=-1094.2 and -31.9 g CO2 m-2 year-¹ for the forest and peatland, respectively); CH4 was mainly captured in the forest and peatland soils, generating balances of -0.70 and -0.12 g CH₄ m-2 year-¹. N2O fluxes were extremely low, so were considered as null. These results indicate that the greenhouse gas balance moved from -1134.6 to -38.8 g CO2-eq m-2 year-1 when land use changed from forest to anthropogenic peatland. These results provide evidence of the importance of preserving old-growth forests in southern Chile.

Balancing natural gas policy : Fueling the demands of a growing economy

International Nuclear Information System (INIS)

Howard, R.

2003-01-01

In March 2002 a request was made to the National Petroleum Council by the United States Secretary of Energy to examine the potential implications of new supplies, technologies, perceptions of risk on natural gas demand, supplies, and delivery through 2025. In addition, the Secretary was looking for insight on energy market dynamics and an outlook on the longer-term sustainability of natural gas supplies. Ideas on ways to improve the productivity and efficiency of North American natural gas markets while ensuring adequate and reliable supplies of energy for consumers were also requested. Two options were examined by the National Petroleum Council (NPC). The reactive path involves public policies which remain in conflict, while the balanced future involves aligned public policies. It was discovered that 75 per cent of long-term American gas needs will be met by traditional North American producing areas which will be unable to meet projected demand. Production growth is desirable in the Rockies and deepwater Gulf of Mexico, as well as non conventional production. After careful examination, it was determined that demand flexibility and efficiency must be improved, along with an increase in supply diversity. Infrastructure must be enhanced and sustained, and efficient markets must be promoted. All these measures would result in higher economic growth, higher employment, and stronger industrial activity. figs

Carbon source/sink function of a subtropical, eutrophic lake determined from an overall mass balance and a gas exchange and carbon burial balance

International Nuclear Information System (INIS)

Yang Hong; Xing Yangping; Xie Ping; Ni Leyi; Rong Kewen

2008-01-01

Although studies on carbon burial in lake sediments have shown that lakes are disproportionately important carbon sinks, many studies on gaseous carbon exchange across the water-air interface have demonstrated that lakes are supersaturated with CO 2 and CH 4 causing a net release of CO 2 and CH 4 to the atmosphere. In order to more accurately estimate the net carbon source/sink function of lake ecosystems, a more comprehensive carbon budget is needed, especially for gaseous carbon exchange across the water-air interface. Using two methods, overall mass balance and gas exchange and carbon burial balance, we assessed the carbon source/sink function of Lake Donghu, a subtropical, eutrophic lake, from April 2003 to March 2004. With the overall mass balance calculations, total carbon input was 14 905 t, total carbon output was 4950 t, and net carbon budget was +9955 t, suggesting that Lake Donghu was a great carbon sink. For the gas exchange and carbon burial balance, gaseous carbon (CO 2 and CH 4 ) emission across the water-air interface totaled 752 t while carbon burial in the lake sediment was 9477 t. The ratio of carbon emission into the atmosphere to carbon burial into the sediment was only 0.08. This low ratio indicates that Lake Donghu is a great carbon sink. Results showed good agreement between the two methods with both showing Lake Donghu to be a great carbon sink. This results from the high primary production of Lake Donghu, substantive allochthonous carbon inputs and intensive anthropogenic activity. Gaseous carbon emission accounted for about 15% of the total carbon output, indicating that the total output would be underestimated without including gaseous carbon exchange. - Due to high primary production, substantive allochthonous carbon inputs and intensive anthropogenic acitivity, subtropical, eutrophic Lake Donghu is a great carbon sink

Balancing Accuracy and Computational Efficiency for Ternary Gas Hydrate Systems

Science.gov (United States)

White, M. D.

2011-12-01

phase transitions. This paper describes and demonstrates a numerical solution scheme for ternary hydrate systems that seeks a balance between accuracy and computational efficiency. This scheme uses a generalize cubic equation of state, functional forms for the hydrate equilibria and cage occupancies, variable switching scheme for phase transitions, and kinetic exchange of hydrate formers (i.e., CH4, CO2, and N2) between the mobile phases (i.e., aqueous, liquid CO2, and gas) and hydrate phase. Accuracy of the scheme will be evaluated by comparing property values and phase equilibria against experimental data. Computational efficiency of the scheme will be evaluated by comparing the base scheme against variants. The application of interest will the production of a natural gas hydrate deposit from a geologic formation, using the guest molecule exchange process; where, a mixture of CO2 and N2 are injected into the formation. During the guest-molecule exchange, CO2 and N2 will predominately replace CH4 in the large and small cages of the sI structure, respectively.

Positive feedback of greenhouse gas balances to warming is determined by non-growing season emissions in an alpine meadow

Science.gov (United States)

Niu, S.; Wang, J.; Quan, Q.; Chen, W.; Wen, X.; Yu, G.

2017-12-01

Large uncertainties exist in the sources and sinks of greenhouse gases (CO2, CH4, N2O) in response to climate warming and human activity. So far, numerous previous studies have evaluated the CO2 budget, but little attention has paid to CH4 and N2O budgets and the concurrent balance of these three gases in combination, especially in the non-growing season. Here, we synthesized eddy covariance measurement with the automatic chamber measurements of CO2, CH4, and N2O exposed to three levels of temperature treatments (ambient, +1.5 °C, +2.5 °C) and two disturbance treatments (ummowing, mowing) in an alpine meadow on the Tibetan Plateau. We have found that warming caused increase in CH4 uptake and decrease in N2O emission offset little of the enhancement in CO2 emission, triggering a positive feedback to climate warming. Warming switches the ecosystem from a net sink (-17 ± 14 g CO2-eq m-2 yr-1) in the control to a net source of greenhouse gases of 94 ± 36 gCO2-eq m-2 yr-1 in the plots with +1.5 °C warming treatment, and 177 ± 6 gCO2-eq m-2 yr-1 in the plots with +2.5 °C warming treatment. The changes in the non-growing season balance, rather than those in the growing season, dominate the warming responses of annual greehouse gas balance. And this is not changed by mowing. The dominant role of responses of winter greenhouse gas balance in the positive feedback of ecosystem to climate warming highlights that greenhouse gas balance in cold season has to be considered when assessing climate-carbon cycle feedback.

Balance Performance Is Task Specific in Older Adults

Directory of Open Access Journals (Sweden)

Ayelet Dunsky

2017-01-01

Full Text Available Balance ability among the elderly is a key component in the activities of daily living and is divided into two types: static and dynamic. For clinicians who wish to assess the risk of falling among their elderly patients, it is unclear if more than one type of balance test can be used to measure their balance impairment. In this study, we examined the association between static balance measures and two dynamic balance field tests. One hundred and twelve community-dwelling older adults (mean age 74.6 participated in the study. They underwent the Tetrax static postural assessment and then performed the Timed Up and Go (TUG and the Functional Reach (FR Test as dynamic balance tests. In general, low-moderate correlations were found between the two types of balance tests. For women, age and static balance parameters explained 28.1–40.4% of the variance of TUG scores and 14.6–24% of the variance of FR scores. For men, age and static balance parameters explained 9.5–31.2% of the variance of TUG scores and 23.9–41.7% of the variance of FR scores. Based on our findings, it is suggested that a combination of both static and dynamic tests be used for assessing postural balance ability.

The future role of peat. The Finnish Ministry of Trade and Industry's investigation on the role of peat in the greenhouse gas balance in Finland

International Nuclear Information System (INIS)

Knuutinen, O.

2000-01-01

Due to contradictory opinions on the role of peat as a renewable energy source and carbon sink as well as the fact that no comprehensive research are made in this area, the Finnish Ministry of Trade and Industry (KTM) assigned an impartial working group to investigate the role of peat in climatic change. The working group consists of Patrick Crill from USA, Ken Hargreaves from Great Britain, and Atte Korhola from Finland. The objective of the working group is to study the greenhouse gas balances of virgin peatland, ditched peatlands, and cultivated peatlands. The carbon cycles will be investigated, as well as the effects of utilisation of peat on greenhouse gas balance, and the possibilities of effecting the balance with active measures. The alternatives for utilisation peatlands after the peat has been harvested, and the effects of these alternatives on greenhouse gas balance will also be studied. The effects of the peatlands left in passive natural state, the regeneration of peatlands, forestation and other usage on greenhouse gas balance will be investigated, and the need for regulations and instructions for recycling have to be estimated. The greenhouse gas emissions and the carbon sinks have to be defined, the alternative means for definition of them have to be inspected. The mutual dependence of peat and wood fuels has also to be taken into consideration. The report will to include the effects of peat on watercourses, versatility of the nature, the effect of the peat production on the amount of peat production areas, and suggestions for possible need of further investigations

Methane mass balance at three landfill sites: What is the efficiency of capture by gas collection systems?

International Nuclear Information System (INIS)

Spokas, K.; Bogner, J.; Chanton, J.P.; Morcet, M.; Aran, C.; Graff, C.; Golvan, Y. Moreau-Le; Hebe, I.

2006-01-01

Many developed countries have targeted landfill methane recovery among greenhouse gas mitigation strategies, since methane is the second most important greenhouse gas after carbon dioxide. Major questions remain with respect to actual methane production rates in field settings and the relative mass of methane that is recovered, emitted, oxidized by methanotrophic bacteria, laterally migrated, or temporarily stored within the landfill volume. This paper presents the results of extensive field campaigns at three landfill sites to elucidate the total methane balance and provide field measurements to quantify these pathways. We assessed the overall methane mass balance in field cells with a variety of designs, cover materials, and gas management strategies. Sites included different cell configurations, including temporary clay cover, final clay cover, geosynthetic clay liners, and geomembrane composite covers, and cells with and without gas collection systems. Methane emission rates ranged from -2.2 to >10,000 mg CH 4 m -2 d -1 . Total methane oxidation rates ranged from 4% to 50% of the methane flux through the cover at sites with positive emissions. Oxidation of atmospheric methane was occurring in vegetated soils above a geomembrane. The results of these studies were used as the basis for guidelines by the French environment agency (ADEME) for default values for percent recovery: 35% for an operating cell with an active landfill gas (LFG) recovery system, 65% for a temporary covered cell with an active LFG recovery system, 85% for a cell with clay final cover and active LFG recovery, and 90% for a cell with a geomembrane final cover and active LFG recovery

Effect of circuit class versus individual task specific training on balance in post-stroke patients

International Nuclear Information System (INIS)

Basri, R.; Ali, A.; Ullah, S.; Naseem, M.; Haq, Z.U.

2017-01-01

Objective: To compare the efficacy of circuit class versus individual, task specific training on balance, in post stroke patients. Methods: From a total of 64 participants, 32 participants were treated in circuit based workstations, while 32 participants were treated individually for 4 weeks. Importantly, both groups were treated with standard balance physiotherapy protocols. The treatment was delivered for 5 days per week with 1.5 hours daily. The patients were evaluated for three outcome measures i.e. berg balance scale, time up and go test and for motor assessment scale at baseline and after treatment. Results: Patients in both groups reported significant improvement after 4 weeks of training program compared to baseline on all outcome measures, except time up and go test that did not significantly improve in individual group. Compared to individual group, circuit group reported more improvement on berg balance scale scores (31.33 versus 37.80), time up and go test (23.13sec versus 16.67sec) and on motor assessment scale scores (18.77 versus 20.63) respectively. Conclusion: Circuit class training is more efficacious in improving balance in stroke patients as compared to individual task specific training. (author)

Multiyear greenhouse gas balances at a rewetted temperate peatland.

Science.gov (United States)

Wilson, David; Farrell, Catherine A; Fallon, David; Moser, Gerald; Müller, Christoph; Renou-Wilson, Florence

2016-12-01

Drained peat soils are a significant source of greenhouse gas (GHG) emissions to the atmosphere. Rewetting these soils is considered an important climate change mitigation tool to reduce emissions and create suitable conditions for carbon sequestration. Long-term monitoring is essential to capture interannual variations in GHG emissions and associated environmental variables and to reduce the uncertainty linked with GHG emission factor calculations. In this study, we present GHG balances: carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) calculated for a 5-year period at a rewetted industrial cutaway peatland in Ireland (rewetted 7 years prior to the start of the study); and compare the results with an adjacent drained area (2-year data set), and with ten long-term data sets from intact (i.e. undrained) peatlands in temperate and boreal regions. In the rewetted site, CO 2 exchange (or net ecosystem exchange (NEE)) was strongly influenced by ecosystem respiration (R eco ) rather than gross primary production (GPP). CH 4 emissions were related to soil temperature and either water table level or plant biomass. N 2 O emissions were not detected in either drained or rewetted sites. Rewetting reduced CO 2 emissions in unvegetated areas by approximately 50%. When upscaled to the ecosystem level, the emission factors (calculated as 5-year mean of annual balances) for the rewetted site were (±SD) -104 ± 80 g CO 2 -C m -2  yr -1 (i.e. CO 2 sink) and 9 ± 2 g CH 4 -C m -2  yr -1 (i.e. CH 4 source). Nearly a decade after rewetting, the GHG balance (100-year global warming potential) had reduced noticeably (i.e. less warming) in comparison with the drained site but was still higher than comparative intact sites. Our results indicate that rewetted sites may be more sensitive to interannual changes in weather conditions than their more resilient intact counterparts and may switch from an annual CO 2 sink to a source if triggered by slightly drier

The real gas dynamics of the fluids of high specific heat

International Nuclear Information System (INIS)

Meier, G.E.A.

1987-01-01

The gas dynamics of real fluids show several new effects beyond the gas dynamics of ideal substances. Many of these effects rely on phase changes in the flow fields and can be explained with the help of more complicated thermal and caloric state equations of the real fluids. Complete adiabatic liquefaction and evaporation are possible for those substances whose specific heat exceeds a limit of about twenty gas constants. These fluids consisting of great molecules have so much internal energy storage capacity in their numerous vibrational degrees of freedom that the heat of evaporation can be supplied or also stored in the case of condensation. So liquefaction shock waves, which transform a gas completely or partly into a liquid, are possible. The shock front becomes thereby the surface of a liquid. Partial liquefaction with droplet condensation occurs in weaker shock waves. On the other hand a superheated liquid with high specific heat can be changed into a gas or mixture state in expansion waves or flows. (orig.)

Gender-specific influences of balance, speed, and power on agility performance.

Science.gov (United States)

Sekulic, Damir; Spasic, Miodrag; Mirkov, Dragan; Cavar, Mile; Sattler, Tine

2013-03-01

The quick change of direction (i.e., agility) is an important athletic ability in numerous sports. Because of the diverse and therefore hardly predictable manifestations of agility in sports, studies noted that the improvement in speed, power, and balance should result in an improvement of agility. However, there is evident lack of data regarding the influence of potential predictors on different agility manifestations. The aim of this study was to determine the gender-specific influence of speed, power, and balance on different agility tests. A total of 32 college-aged male athletes and 31 college-aged female athletes (age 20.02 ± 1.89 years) participated in this study. The subjects were mostly involved in team sports (soccer, team handball, basketball, and volleyball; 80% of men, and 75% of women), martial arts, gymnastics, and dance. Anthropometric variables consisted of body height, body weight, and the body mass index. Five agility tests were used: a t-test (T-TEST), zig-zag test, 20-yard shuttle test, agility test with a 180-degree turn, and forward-backward running agility test (FWDBWD). Other tests included 1 jumping ability power test (squat jump, SQJ), 2 balance tests to determine the overall stability index and an overall limit of stability score (both measured by Biodex Balance System), and 2 running speed tests using a straight sprint for 10 and 20 m (S10 and S20, respectively). A reliability analysis showed that all the agility tests were reliable. Multiple regression and correlation analysis found speed and power (among women), and balance (among men), as most significant predictors of agility. The highest Pearson's correlation in both genders is found between the results of the FWDBWD and S10M tests (0.77 and 0.81 for men and women, respectively; p Power, measured using the SQJ, is significantly (p balance measures were significantly related to the agility performance for men but not for women. In addition to demonstrating a known relationship

Validating a dance-specific screening test for balance: preliminary results from multisite testing.

Science.gov (United States)

Batson, Glenna

2010-09-01

Few dance-specific screening tools adequately capture balance. The aim of this study was to administer and modify the Star Excursion Balance Test (oSEBT) to examine its utility as a balance screen for dancers. The oSEBT involves standing on one leg while lightly targeting with the opposite foot to the farthest distance along eight spokes of a star-shaped grid. This task simulates dance in the spatial pattern and movement quality of the gesturing limb. The oSEBT was validated for distance on athletes with history of ankle sprain. Thirty-three dancers (age 20.1 +/- 1.4 yrs) participated from two contemporary dance conservatories (UK and US), with or without a history of lower extremity injury. Dancers were verbally instructed (without physical demonstration) to execute the oSEBT and four modifications (mSEBT): timed (speed), timed with cognitive interference (answering questions aloud), and sensory disadvantaging (foam mat). Stepping strategies were tracked and performance strategies video-recorded. Unlike the oSEBT results, distances reached were not significant statistically (p = 0.05) or descriptively (i.e., shorter) for either group. Performance styles varied widely, despite sample homogeneity and instructions to control for strategy. Descriptive analysis of mSEBT showed an increased number of near-falls and decreased timing on the injured limb. Dancers appeared to employ variable strategies to keep balance during this test. Quantitative analysis is warranted to define balance strategies for further validation of SEBT modifications to determine its utility as a balance screening tool.

Parkinsonian Balance Deficits Quantified Using a Game Industry Board and a Specific Battery of Four Paradigms.

Science.gov (United States)

Darbin, Olivier; Gubler, Coral; Naritoku, Dean; Dees, Daniel; Martino, Anthony; Adams, Elizabeth

2016-01-01

This study describes a cost-effective screening protocol for parkinsonism based on combined objective and subjective monitoring of balance function. Objective evaluation of balance function was performed using a game industry balance board and an automated analyses of the dynamic of the center of pressure in time, frequency, and non-linear domains collected during short series of stand up tests with different modalities and severity of sensorial deprivation. The subjective measurement of balance function was performed using the Dizziness Handicap Inventory questionnaire. Principal component analyses on both objective and subjective measurements of balance function allowed to obtained a specificity and selectivity for parkinsonian patients (vs. healthy subjects) of 0.67 and 0.71 respectively. The findings are discussed regarding the relevance of cost-effective balance-based screening system as strategy to meet the needs of broader and earlier screening for parkinsonism in communities with limited access to healthcare.

Greenhouse gas balance of an establishing Sphagnum culture on a former bog grassland in Germany

OpenAIRE

A. Günther; G. Jurasinski; K. Albrecht; G. Gaudig; M. Krebs; S. Glatzel

2017-01-01

The cultivation of Sphagnum mosses on re-wetted peat bogs for use in horticulture is a new land use strategy. We provide the first greenhouse gas balances for a field-scale Sphagnum farming experiment on former bog grassland, in its establishment phase. Over two years we used closed chambers to make measurements of GHG exchange on production strips of Sphagnum palustre L. and Sphagnum papillosum Lindb. and on irrigation ditches. Methane fluxes of both Sphagnum species showed a significant dec...

Parkinsonian balance deficits quantified using a game industry board and a specific battery of four paradigms.

Directory of Open Access Journals (Sweden)

Olivier Darbin

2016-08-01

Full Text Available This study describes a cost-effective screening protocol for parkinsonism based on combined objective and subjective monitoring of balance function. Objective evaluation of balance function was performed using a game industry balance board and an automated analyses of the dynamic of the center of pressure in time, frequency and non-linear domains collected during short series of stand up tests with different modalities and severity of sensorial deprivation. The subjective measurement of balance function was performed using the Dizziness Handicap Inventory questionnaire. Principal component analyses on both objective and subjective measurements of balance function allowed to obtained a specificity and selectivity for parkinsonian patients (v.s. healthy subjects of 0.67 and 0.71 respectively. The findings are discussed regarding the relevance of cost-effective balance-based screening system as strategy to meet the needs of broader and earlier screening for parkinsonism in communities with limited access to healthcare.

Implications of possible interpretations of "greenhouse gas balance" in the Paris Agreement

Science.gov (United States)

Millar, R.; Fuglestvedt, J. S.; Rogelj, J.; Allen, M. R.; Boucher, O.; Forster, P.; Kriegler, E.; Shindell, D. T.

2017-12-01

The main goal of the Paris Agreement as stated in its Article 2 is "Holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C above pre-industrial levels…". Article 4 points to this long-term goal and the need to "… achieve balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases …". The statement on "greenhouse gas balance" is subject to interpretation, and several clarifications are needed in order to make it operational for implementation in climate policies. Here we study possible interpretations from a scientific perspective and analyze their climatic implications. We clarify how the balance referred to in Article 4 of the Paris Agreement applies to anthropogenic sources and anthropogenic sinks and how the implications for individual gases depends strongly on the emission metrics used to relate them. We also show that the way in which balance is interpreted, achieved and maintained influences the anticipated temperature outcome over time. For example, achieving and maintaining net zero CO2-equivalent emissions calculated with the widely used metric Global Warming Potential with a horizon of 100 years (GWP100) - adopted for the implementation of the Kyoto Protocol and in UNFCCC reporting - would result in a peak and decline in global mean temperature. Adopting a different metric, like GWP* (Allen et al., 2016), would result in global mean temperatures remaining approximately constant once net zero CO2-equivalent emissions are achieved and maintained. Policymakers should be aware of these issues and choices and determine which approach is most appropriate in the context of the goals of the Paris Agreement.Reference:Allen, Fuglestvedt, Shine, Reisinger, Pierrehumbert, Forster: New use of global warming potentials to compare cumulative and short-lived climate pollutants. Nature Climate Change (2016). doi:10

Implications of possible interpretations of 'greenhouse gas balance' in the Paris Agreement.

Science.gov (United States)

Fuglestvedt, J; Rogelj, J; Millar, R J; Allen, M; Boucher, O; Cain, M; Forster, P M; Kriegler, E; Shindell, D

2018-05-13

The main goal of the Paris Agreement as stated in Article 2 is 'holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C'. Article 4 points to this long-term goal and the need to achieve 'balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases'. This statement on 'greenhouse gas balance' is subject to interpretation, and clarifications are needed to make it operational for national and international climate policies. We study possible interpretations from a scientific perspective and analyse their climatic implications. We clarify how the implications for individual gases depend on the metrics used to relate them. We show that the way in which balance is interpreted, achieved and maintained influences temperature outcomes. Achieving and maintaining net-zero CO 2 -equivalent emissions conventionally calculated using GWP 100 (100-year global warming potential) and including substantial positive contributions from short-lived climate-forcing agents such as methane would result in a sustained decline in global temperature. A modified approach to the use of GWP 100 (that equates constant emissions of short-lived climate forcers with zero sustained emission of CO 2 ) results in global temperatures remaining approximately constant once net-zero CO 2 -equivalent emissions are achieved and maintained. Our paper provides policymakers with an overview of issues and choices that are important to determine which approach is most appropriate in the context of the Paris Agreement.This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. © 2018 The Authors.

Implications of possible interpretations of `greenhouse gas balance' in the Paris Agreement

Science.gov (United States)

Fuglestvedt, J.; Rogelj, J.; Millar, R. J.; Allen, M.; Boucher, O.; Cain, M.; Forster, P. M.; Kriegler, E.; Shindell, D.

2018-05-01

The main goal of the Paris Agreement as stated in Article 2 is `holding the increase in the global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5°C'. Article 4 points to this long-term goal and the need to achieve `balance between anthropogenic emissions by sources and removals by sinks of greenhouse gases'. This statement on `greenhouse gas balance' is subject to interpretation, and clarifications are needed to make it operational for national and international climate policies. We study possible interpretations from a scientific perspective and analyse their climatic implications. We clarify how the implications for individual gases depend on the metrics used to relate them. We show that the way in which balance is interpreted, achieved and maintained influences temperature outcomes. Achieving and maintaining net-zero CO2-equivalent emissions conventionally calculated using GWP100 (100-year global warming potential) and including substantial positive contributions from short-lived climate-forcing agents such as methane would result in a sustained decline in global temperature. A modified approach to the use of GWP100 (that equates constant emissions of short-lived climate forcers with zero sustained emission of CO2) results in global temperatures remaining approximately constant once net-zero CO2-equivalent emissions are achieved and maintained. Our paper provides policymakers with an overview of issues and choices that are important to determine which approach is most appropriate in the context of the Paris Agreement. This article is part of the theme issue `The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

The Precise Mechanisms of a High-Speed Ultrasound Gas Sensor and Detecting Human-Specific Lung Gas Exchange

Directory of Open Access Journals (Sweden)

Hideki Toda

2012-12-01

Full Text Available In this paper, we propose and develop a new real-time human respiration process analysis method using a high-time-sampling gas concentration sensor based on ultrasound. A unique point about our proposed gas concentration sensor is its 1 kHz gas concentration sampling speed. This figure could not have been attained by previously proposed gas concentration measurement methods such as InfraRed, semiconductor gas sensors, or GC-MS, because the gas analysis speeds were a maximum of a few hundred milliseconds. First, we describe the proposed new ultrasound sound speed measurement method and the signal processing, and present the measurement circuit diagram. Next, we analyse the human respiration gas variation patterns of five healthy subjects using a newly developed gas-mask-type respiration sensor. This reveals that the rapid gas exchange from H2O to CO2 contains air specific to the human being. In addition, we also measured medical symptoms in subjects suffering from asthma, hyperventilation and bronchial asthma. The millisecond level high-speed analysis of the human respiration process will be useful for the next generation of healthcare, rehabilitation and sports science technology.

TECHNOLOGIES TO ENHANCE THE OPERATION OF EXISTING NATURAL GAS COMPRESSION INFRASTRUCTURE - MANIFOLD DESIGN FOR CONTROLLING ENGINE AIR BALANCE

Energy Technology Data Exchange (ETDEWEB)

Gary D. Bourn; Ford A. Phillips; Ralph E. Harris

2005-12-01

This document provides results and conclusions for Task 15.0--Detailed Analysis of Air Balance & Conceptual Design of Improved Air Manifolds in the ''Technologies to Enhance the Operation of Existing Natural Gas Compression Infrastructure'' project. SwRI{reg_sign} is conducting this project for DOE in conjunction with Pipeline Research Council International, Gas Machinery Research Council, El Paso Pipeline, Cooper Compression, and Southern Star, under DOE contract number DE-FC26-02NT41646. The objective of Task 15.0 was to investigate the perceived imbalance in airflow between power cylinders in two-stroke integral compressor engines and develop solutions via manifold redesign. The overall project objective is to develop and substantiate methods for operating integral engine/compressors in gas pipeline service, which reduce fuel consumption, increase capacity, and enhance mechanical integrity.

Material and energy balances of an integrated biological hydrogen production and purification system and their implications for its potential to reduce greenhouse gas emissions.

Science.gov (United States)

Fukushima, Yasuhiro; Huang, Yu-Jung; Chen, Jhen-Wei; Lin, Hung-Chun; Whang, Liang-Ming; Chu, Hsin; Lo, Young-Chong; Chang, Jo-Shu

2011-09-01

The materials and energy in an integrated biological hydrogen production and purification system involving hydrolysis, dark fermentation, photo fermentation, CO2 fixation and anaerobic digestion are balanced by integrating the results from multiple experiments, simulations and the literature. The findings are two fold. First, using 1000 kg rice straw as a substrate, 19.8 kg H2 and 138.0 kg CH4 are obtained. The net energy balance (NEB) and net energy ratio (NER) are -738.4 kWh and 77.8%, respectively, both of which imply an unfavorable energy production system. Opportunities to improve the performance particularly lie in the photo fermentation process. Second, greenhouse gas emissions are evaluated for various options. The results were comparable with the emission inventory of electricity generated from fossil fuels. NEB and NER under a zero-carbon-emission constraint were discussed in detail to clarify completely the implications of the energy and material balances on greenhouse gas emissions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of specific muscle imbalance improvement training on the balance ability in elite fencers.

Science.gov (United States)

Kim, Taewhan; Kil, Sekee; Chung, Jinwook; Moon, Jeheon; Oh, Eunyoung

2015-05-01

[Purpose] The lunge Motion that occurs frequently in fencing training and matches results in imbalance of the upper and lower limbs muscles. This research focuses on the improvement of the imbalance that occurs in the national team fencers of the Republic of Korea through specific muscle imbalance improvement training. [Subjects] The subjects of this research were limited to right-handed male fencers. Nine male, right-handed national fencing athletes were selected for this study (4 epee, 5 sabre; age 28.2 ± 2.2 years; height 182.3 ± 4.0 cm; weight 76.5 ± 8.2 kg; experience 12.4 ± 3.0 years). [Methods] The specific muscle imbalance improvement training program was performed for 12 weeks and Pre-Post tests were to evaluate its effect on the experimental group. Measurements comprised anthropometry, test of balance, and movement analysis. [Results] After the training program, mediolateral sway of the nondominant lower limb and the balance scale showed statistically significant improvement. [Conclusion] The specific muscle imbalance improvement training program used in this research was proven to be effective for improving the muscle imbalance of elite fencers.

Energy budget and greenhouse gas balance evaluation of sustainable coppice systems for electricity production

International Nuclear Information System (INIS)

Lettens, Suzanna; Muys, Bart; Ceulemans, Reinhart; Moons, Ellen; Garcia, Juan; Coppin, Pol

2003-01-01

The use of bio-energy crops for electricity production is considered an effective means to mitigate the greenhouse effect, mainly due to its ability to substitute fossil fuels. A whole range of crops qualify for bio-energy production and a rational choice is not readily made. This paper evaluates the energy and greenhouse gas balance of a mixed indigenous hardwood coppice as an extensive, low-input bio-energy crop. The impact on fossil energy use and greenhouse gas emission is calculated and discussed by comparing its life cycle (cultivation, processing and conversion into energy) with two conventional bio-energy crops (short rotation systems of willow and Miscanthus). For each life cycle process, the flows of fossil energy and greenhouse gas that are created for the production of one functional unit are calculated. The results show that low-input bio-energy crops use comparatively less fossil fuel and avoid more greenhouse gas emission per unit of produced energy than conventional bio-energy crops during the first 100 yr. Where the mixed coppice system avoids up till 0.13 t CO 2 eq./GJ, Miscanthus does not exceed 0.07 t CO 2 eq./GJ. After 100 yr their performances become comparable, amounting to 0.05 t CO 2 eq./ha/GJ. However, if the land surface itself is chosen as a functional unit, conventional crops perform better with respect to mitigating the greenhouse effect. Miscanthus avoids a maximum of 12.9 t CO 2 eq./ha/yr, while mixed coppice attains 9.5 t CO 2 eq./ha/yr at the most

Equation of material balance for systems of double porosity with layer of initial gas

International Nuclear Information System (INIS)

Niz, Eider; Hidrobo, Eduardo A; Penuela, Gherson; Ordonez, Anibal; Calderon, Zuly H

2004-01-01

The physical complexity associated to naturally fractured reservoirs calls for the use of more robust formulations of the Material-Balance Equation (MBE) for determining the initial hydrocarbon in place and predicting reservoir performance. In this paper, we present an improved version of the dual-porosity MBE for naturally fractured reservoirs, published by Penuela et al. (2001), including the existence of an initial gas phase in the reservoir. Considering that a fractured reservoir may be modeled either using different properties for each porous medium or with average values for the total system, two solution techniques based on each of these assumptions are proposed. Convenient arrangements of the equation allow us to estimate not only the original oil and gas volumes but also the relative storage capacity of the porous media (fractures and matrix) and the compressibility for the fractured and total systems. The new equation can be applied to a broader range of reservoirs due to its more general character. The consistency of the expression proposed has been tested with a set of synthetic models exhibiting different storage capacity in the fractures

Gas chromatographic isolation technique for compound-specific radiocarbon analysis

International Nuclear Information System (INIS)

Uchida, M.; Kumamoto, Y.; Shibata, Y.; Yoneda, M.; Morita, M.; Kawamura, K.

2002-01-01

Full text: We present here a gas chromatographic isolation technique for the compound-specific radiocarbon analysis of biomarkers from the marine sediments. The biomarkers of fatty acids, hydrocarbon and sterols were isolated with enough amount for radiocarbon analysis using a preparative capillary gas chromatograph (PCGC) system. The PCGC systems used here is composed of an HP 6890 GC with FID, a cooled injection system (CIS, Gerstel, Germany), a zero-dead-volume effluent splitter, and a cryogenic preparative collection device (PFC, Gerstel). For AMS analysis, we need to separate and recover sufficient quantity of target individual compounds (>50 μgC). Yields of target compounds from C 14 n-alkanes to C 40 to C 30 n-alkanes and approximately that of 80% for higher molecular weights compounds more than C 30 n-alkanes. Compound specific radiocarbon analysis of organic compounds, as well as compound-specific stable isotope analysis, provide valuable information on the origins and carbon cycling in marine system. Above PCGC conditions, we applied compound-specific radiocarbon analysis to the marine sediments from western north Pacific, which showed the possibility of a useful chronology tool for estimating the age of sediment using organic matter in paleoceanographic study, in the area where enough amounts of planktonic foraminifera for radiocarbon analysis by accelerator mass spectrometry (AMS) are difficult to obtain due to dissolution of calcium carbonate. (author)

Effects of a 12-month task-specific balance training on the balance status of stroke survivors with and without cognitive impairments in Selected Hospitals in Nnewi, Anambra State, Nigeria.

Science.gov (United States)

Okonkwo, Uchenna Prosper; Ibeneme, Sam Chidi; Ihegihu, Ebere Yvonne; Egwuonwu, Afamefuna Victor; Ezema, Charles Ikechukwu; Maruf, Fatai Adesina

2018-05-02

Stroke results in varying levels of physical disabilities that may adversely impact balance with increased tendency to falls. This may intensify with cognitive impairments (CI), and impede functional recovery. Therefore, task-specific balance training (TSBT), which presents versatile task-specific training options that matches varied individual needs, was explored as a beneficial rehabilitation regime for stroke survivors with and without CI. It was hypothesized that there will be no significant difference in the balance control measures in stroke survivors with and without CI after a 12-month TSBT. To determine if TSBT will have comparable beneficial effects on the balance control status of sub-acute ischemic stroke survivors with CI and without CI. One hundred of 143 available sub-acute first ever ischemic stroke survivors were recruited using convenience sampling technique in a quasi-experimental study. They were later assigned into the cognitive impaired group (CIG) and non-cognitive impaired group (NCIG), respectively, based on the baseline presence or absence of CI, after screening with the mini-mental examination (MMSE) tool. With the help of four trained research assistants, TSBT was applied to each group, thrice times a week, 60 mins per session, for 12 months. Their balance was measured as Bergs Balance scores (BBS) at baseline, 4th, 8th, and 12th month intervals. Data were analyzed statistically using Kruskal Wallis test, and repeated measure ANOVA, at p balance control of CIG with large effect size of 0.69 after 12 months of TSBT. There was also significant improvement across time points in the balance control of NCIG with large effect size of 0.544 after 12 months of TSBT. There was no significant difference between the improvement in CIG and NCIG after 8th and 12th months of TSBT.  Within the groups, a 12-month TSBT intervention significantly improved balance control, respectively, but with broader effects in the

Natural gas: redistributing the economic surplus

International Nuclear Information System (INIS)

Oliveira, A. de; Pinto Junior, H.Q.

1990-01-01

The natural gas has a limited role in the Brazilian energy balance. This role in industrial countries and some developing countries is much more important. Historically this contrasting situation can be explained by the limited natural gas reserves Brazil used to have. Since the oil crisis however the Brazilian natural gas reserves increased substantially without a similar increase in the role of natural gas in the energy balance. The existing institutional arrangement generates a struggle for the economic rent generated by natural gas production and consumption that seems to be at the core of this question. Our paper estimates the economic rent generated by natural gas in Brazil and its distribution among producers and consumers: it points toward a new institutional arrangement that could arguably, generate a new role for the natural gas in the Brazilian energy balance. (author)

Anaerobic Digestion: Mass Balances and Products

DEFF Research Database (Denmark)

Møller, Jacob; Christensen, Thomas Højlund; Jansen, Jes la Cour

2011-01-01

While the basic processes involved in anaerobic digestion of waste are described in Chapter 9.4 and the main digestion technologies are presented in Chapter 9.5, this chapter focuses on mass balances, gas production and energy aspects, environmental emissions and unit process inventories. Underst......While the basic processes involved in anaerobic digestion of waste are described in Chapter 9.4 and the main digestion technologies are presented in Chapter 9.5, this chapter focuses on mass balances, gas production and energy aspects, environmental emissions and unit process inventories...

Effects of xylazine on acid-base balance and arterial blood-gas tensions in goats under different environmental temperature and humidity conditions

Directory of Open Access Journals (Sweden)

E.G.M. Mogoa

2000-07-01

Full Text Available The effects of acute exposure to 3 different temperature and humidity conditions on arterial blood-gas and acid-base balance in goats were investigated after intravenous bolus administration of xylazine at a dose of 0.1 mg/kg. Significant (P < 0.05 changes in the variables occurred under all 3 environmental conditions. Decreases in pH, partial pressure of oxygen and oxyhaemoglobin saturation were observed, and the minimum values for oxygen tension and oxyhaemoglobin saturation were observed within 5 min of xylazine administration. The pH decreased to its minimum values between 5 and 15 min. Thereafter, the variables started to return towards baseline, but did not reach baseline values at the end of the 60 min observation period. Increases in the partial pressure of carbon dioxide, total carbon dioxide content, bicarbonate ion concentration, and the actual base excess were observed. The maximum increase in the carbon dioxide tension occurred within 5 min of xylazine administration. The increase in the actual base excess only became significant after 30 min in all 3 environments, and maximal increases were observed at 60 min. There were no significant differences between the variables in the 3 different environments. It was concluded that intravenous xylazine administration in goats resulted in significant changes in arterial blood-gas and acid-base balance that were associated with hypoxaemia and respiratory acidosis, followed by metabolic alkalosis that continued for the duration of the observation period. Acute exposure to different environmental temperature and humidity conditions after xylazine administration did not influence the changes in arterial blood-gas and acid-base balance.

Psychometric Properties of Persian Translated Version of Activities-specific Balance Confidence Scale (ABC in Arak Community-dwelling Older Adults

Directory of Open Access Journals (Sweden)

Daryoush Khajavi

2017-11-01

Full Text Available Abstract Background: Balance deficiency, falls and fear of fall are important problems that can resulted in reversed health outcomes including decreased quality of life. The purpose of this study was surveying factor structure, validation, and reliability determination of Persian translated version of Activities-specific Balance Confidence scale in community-dwelling older adults of Arak city. Materials and Methods: Research method was descriptive in form of psychometry. The statistic population was older adults of Arak in year 2012 and 308 subjects with mean age 69.38 years were selected availably. Data were collected by Persian translated version of Activities-specific Balance Confidence that is a 16-item scale and evaluates balance confidence in activities of daily living. Data were analyzed by Exploratory Factor Analysis. Test-retest and internal reliability were calculated by Pearson correlation coefficient and Chronbach’s Alpha. Data were analyzed with SPSS-16. Results: The findings resulted in extraction of one factor with eigenvalue over one that explained 82.89% of total variance. Test-retest reliability between 1 to 4 weeks and internal reliability (Chronbach’s alpha were 0.82 and 0.98, respectively. Gutmann split-half correlation coefficient and intra-class correlation coefficient were calculated 95% and 85%, respectively. Conclusion: Persian translated version of Activities-specific Balance Confidence (ABC-F is a valid and reliable tool for Iranian community-dwelling older adults that can be used in clinical and research purpose.

Balance sheet for the gas system in 2014

International Nuclear Information System (INIS)

2015-01-01

GRTgaz is a European leader in natural gas transmission, a world expert in gas transmission networks and systems, and an operator firmly committed to the energy transition. It owns and operates the gas transmission network throughout most of France and it manages the transmission network in Germany, thereby helping to ensure correct operation of the French and European gas market. It contributes to the energy security of regional supply systems and performs a public service mission to ensure the continuity of consumer supply. This document presents some key figures about GRTgaz activity in 2014: 2014, France's warmest year ever observed (2014, warm / 2013, cold). Total Consumption 2014 vs 2013: -16.5% gross consumption, -5.4% climate adjusted. Public Distribution Consumption 2014 vs 2013: -19.2% gross consumption, -2.2% climate adjusted. Power Generation: -60% since 2011, 2014 vs 2013: -34%. Industrial Consumption has remained stable over the past 10 years. Stable industrial capacity subscriptions (excluding power generation). Transported Quantities by GRTgaz 2014 vs 2013 (-8.4%). Increasing flows from North to South. Imports fall connected to consumption fall, but soften by gas transit flows. Very low LNG imports but LNG was back at the end of 2014. Largely increasing gas transit 2014 vs 2013: +41%. Good level in the UGS at the beginning of the winter 2014/2015. Congestion on North-South link, Congested European North-South corridor. Price spread between North and South disappeared in November and December 2014. In 2014, Gas gross consumption fell by 16.5% in comparison with 2013, essentially because of exceptionally warm climatic conditions. Industrial consumption excluding power generation resists and has remained relatively stable over the past ten years. However gas consumption for power generation continued to fall since 2011. In 2014, GRTgaz's gas transmission network ran under unusual gas flow conditions, especially with a continuing decrease of

Herbaceous biomass supply chains : assessing the greenhouse gas balance, economics and ILUC effects of Ukrainian biomass for domestic and Dutch energy markets

NARCIS (Netherlands)

Poppens, R.P.; Lesschen, J.P.; Galytska, M.; Jamblinne, de P.; Kraisvitnii, P.; Elbersen, H.W.

2013-01-01

This report describes the supply chain performance for three types of biomass feedstock (reed, straw and switchgrass) and for three sustainability aspects, i.e. the greenhouse gas balance, economics and Indirect Land Use change effects (ILUC). Calculations are based on a fictional supply chain

Greenhouse gas balance over thaw-freeze cycles in discontinuous zone permafrost

Science.gov (United States)

Wilson, R. M.; Fitzhugh, L.; Whiting, G. J.; Frolking, S.; Harrison, M. D.; Dimova, N.; Burnett, W. C.; Chanton, J. P.

2017-02-01

Peat in the discontinuous permafrost zone contains a globally significant reservoir of carbon that has undergone multiple permafrost-thaw cycles since the end of the mid-Holocene ( 3700 years before present). Periods of thaw increase C decomposition rates which leads to the release of CO2 and CH4 to the atmosphere creating potential climate feedback. To determine the magnitude and direction of such feedback, we measured CO2 and CH4 emissions and modeled C accumulation rates and radiative fluxes from measurements of two radioactive tracers with differing lifetimes to describe the C balance of the peatland over multiple permafrost-thaw cycles since the initiation of permafrost at the site. At thaw features, the balance between increased primary production and higher CH4 emission stimulated by warmer temperatures and wetter conditions favors C sequestration and enhanced peat accumulation. Flux measurements suggest that frozen plateaus may intermittently (order of years to decades) act as CO2 sources depending on temperature and net ecosystem respiration rates, but modeling results suggest that—despite brief periods of net C loss to the atmosphere at the initiation of thaw—integrated over millennia, these sites have acted as net C sinks via peat accumulation. In greenhouse gas terms, the transition from frozen permafrost to thawed wetland is accompanied by increasing CO2 uptake that is partially offset by increasing CH4 emissions. In the short-term (decadal time scale) the net effect of this transition is likely enhanced warming via increased radiative C emissions, while in the long-term (centuries) net C deposition provides a negative feedback to climate warming.

Approach to IAEA material-balance verification at the Portsmouth Gas Centrifuge Enrichment Plant

International Nuclear Information System (INIS)

Gordon, D.M.; Sanborn, J.B.; Younkin, J.M.; DeVito, V.J.

1983-01-01

This paper describes a potential approach by which the International Atomic Energy Agency (IAEA) might verify the nuclear-material balance at the Portsmouth Gas Centrifuge Enrichment Plant (GCEP). The strategy makes use of the attributes and variables measurement verification approach, whereby the IAEA would perform independent measurements on a randomly selected subset of the items comprising the U-235 flows and inventories at the plant. In addition, the MUF-D statistic is used as the test statistic for the detection of diversion. The paper includes descriptions of the potential verification activities, as well as calculations of: (1) attributes and variables sample sizes for the various strata, (2) standard deviations of the relevant test statistics, and (3) the detection sensitivity which the IAEA might achieve by this verification strategy at GCEP

Growth Arrest-Specific 6 (Gas6) and TAM Receptors in Mouse Platelets.

Science.gov (United States)

Uras, Fikriye; Küçük, Burhanettin; Bingöl Özakpınar, Özlem; Demir, Ahmet Muzaffer

2015-03-05

Growth arrest-specific 6 (Gas6) is a newly discovered vitamin K-dependent protein, which is a ligand for TAM receptors [Tyro3 (Sky), Axl, and Mer] from the tyrosine kinase family. Gas6 knockout mice were resistant to venous and arterial thrombosis. There are contradictory reports on the presence of Gas6 and its receptors in mouse platelets. The objective of this study was to investigate whether Gas6 and its receptors were present in mouse platelets or not. Specific pathogen-free BALB/c male and female mice of 8-10 weeks old and 25-30 g in weight were anesthetized under light ether anesthesia and blood samples were taken from their hearts. RNAs were isolated from isolated platelets, and then mRNAs encoding Gas6 and TAM receptors were detected by reverse transcription-polymerase chain reaction (RT-PCR). Protein concentrations of Gas6 and TAM receptors in platelets were measured by ELISA, but not those of Mer, because of the absence of any commercial ELISA kit for mouse specimens. RT-PCR results indicated the presence of mRNAs encoding Gas6 and Mer in mouse platelets. However, although RT-PCR reactions were performed at various temperatures and cycles, we could not detect the presence of mRNAs encoding Axl and Tyro3 (Sky). Receptor protein levels of Axl and Tyro3 were below the detection limits of the ELISA method. We found the presence of mRNAs encoding Gas6 and the receptor Mer in mouse platelets, but not Axl and Tyro3. Gas6, Axl, and Tyro3 protein levels were below the detection limits of the ELISA. The presence of mRNA is not obvious evidence of protein expression in platelets that have no nucleus or DNA. Further studies are required to clarify the presence of Gas6/TAM receptors in platelets using real-time PCR and more sensitive immunological methods, and future studies on mechanisms will indicate whether the Gas6/TAM pathway is a strategy for treatment of disorders.

Application of precise MPD & pressure balance cementing technology

Directory of Open Access Journals (Sweden)

Yong Ma

2018-03-01

Full Text Available The precise managed pressure drilling (MPD technology is mainly used to deal with the difficulties encountered when oil and gas open hole sections with multiple pressure systems and the strata with narrow safety density window are drilled through. If its liner cementing is carried out according to the conventional method, lost circulation is inevitable in the process of cementing while the displacement efficiency of small-clearance liner cementing is satisfied. If the positive and inverse injection technology is adopted, the cementing quality cannot meet the requirements of later well test engineering of ultradeep wells. In this paper, the cementing operation of Ø114.3 mm liner in Well Longgang 70 which was drilled in the Jiange structure of the Sichuan Basin was taken as an example to explore the application of the cementing technology based on the precise MPD and pressure balancing method to the cementing of long open-hole sections (as long as 859 m with both high and low pressures running through multiple reservoirs. On the one hand, the technical measures were taken specifically to ensure the annulus filling efficiency of slurry and the pressure balance in the whole process of cementing. And on the other hand, the annulus pressure balance was precisely controlled by virtue of precise MPD devices and by injecting heavy weight drilling fluids through central pipes, and thus the wellbore pressure was kept steady in the whole process of cementing in the strata with narrow safety density window. It is indicated that Ø114.3 mm liner cementing in this well is good with qualified pressure tests and no channeling emerges at a funnel during the staged density reduction. It is concluded that this method can enhance the liner cementing quality of complex ultradeep gas wells and improve the wellbore conditions for the later safe well tests of high-pressure gas wells. Keywords: Ultradeep well, Liner cementing, Narrow safety density window, Precise

Energy and greenhouse gas balances of cassava-based ethanol

International Nuclear Information System (INIS)

Le, Loan T.; Ierland, Ekko C. van; Zhu, Xueqin; Wesseler, Justus

2013-01-01

Biofuel production has been promoted to save fossil fuels and reduce greenhouse gas (GHG) emissions. However, there have been concerns about the potential of biofuel to improve energy efficiency and mitigate climate change. This paper investigates energy efficiency and GHG emission saving of cassava-based ethanol as energy for transportation. Energy and GHG balances are calculated for a functional unit of 1 km of road transportation using life-cycle assessment and considering effects of land use change (LUC). Based on a case study in Vietnam, the results show that the energy input for and GHG emissions from ethanol production are 0.93 MJ and 34.95 g carbon dioxide equivalent per megajoule of ethanol respectively. The use of E5 and E10 as a substitute for gasoline results in energy savings, provided that their fuel consumption in terms of liter per kilometer of transportation is not exceeding the consumption of gasoline per kilometer by more than 2.4% and 4.5% respectively. It will reduce GHG emissions, provided that the fuel consumption of E5 and E10 is not exceeding the consumption of gasoline per kilometer by more than 3.8% and 7.8% respectively. The quantitative effects depend on the efficiency in production and on the fuel efficiency of E5 and E10. The variations in results of energy input and GHG emissions in the ethanol production among studies are due to differences in coverage of effects of LUC, CO 2 photosynthesis of cassava, yields of cassava, energy efficiency in farming, and by-product analyses. -- Highlights: ► Cassava-based ethanol substitution for gasoline in form of E5 could save 1.4 MJ km −1 ► Ethanol substitution for gasoline in form of E5 reduces a CO 2 e emission of 156 g km −1 ► We examined changes in fuel efficiency of blends affecting energy and GHG balances. ► LUC and change in soil management lead to a CO 2 e emission of 942 g L −1 of ethanol. ► LUC effects, energy inputs, yields, and by-products explain results among

Do budget balance rules anchor budget balance expectations? -- Some international evidence

OpenAIRE

Rülke, Jan-Christoph; Frenkel, Michael; Lis, Eliza

2013-01-01

This is the first study that analyzes whether budget balance expectations are anchored and whether budget balance rules effectively anchor expectations. To this end, we use a unique data set which covers budget balance expectations in 17 countries that implemented a budget balance rules. While our results are mixed concerning the general impact of budget balance rules on anchoring expectations, we do find that specific features of budget balance rules are important to successfully anchor budg...

Greenhouse gas balances of biomass energy systems

International Nuclear Information System (INIS)

Marland, G.; Schlamadinger, B.

1996-01-01

A full energy-cycle analysis of greenhouse gas emissions of biomass energy systems requires analysis well beyond the energy sector. For example, production of biomass fuels impacts on the global carbon cycle by altering the amount of carbon stored in the biosphere and often by producing a stream of by-products or co-products which substitute for other energy-intensive products like cement, steel, concrete or, in case of ethanol form corn, animal feed. It is necessary to distinguish between greenhouse gas emissions associated with the energy product as opposed to those associated with other products. Production of biomass fuels also has an opportunity cost because it uses large land areas which could have been used otherwise. Accounting for the greenhouse gas emissions from biomass fuels in an environment of credits and debits creates additional challenges because there are large non-linearities in carbon flows over time. This paper presents some of the technical challenges of comprehensive greenhouse gas accounting and distinguishes between technical and public policy issues. (author). 5 refs, 5 figs

Greenhouse gas balances of biomass energy systems

International Nuclear Information System (INIS)

Marland, G.; Schlamadinger, B.

1994-01-01

A full energy-cycle analysis of greenhouse gas emissions of biomass energy systems requires analysis well beyond the energy sector. For example, production of biomass fuels impacts on the global carbon cycle by altering the amount of carbon stored in the biosphere and often by producing a stream of by-products or co-products which substitute for other energy-intensive products like cement, steel, concrete or, in case of ethanol from corn, animal feed. It is necessary to distinguish between greenhouse gas emissions associated with the energy product as opposed to those associated with other products. Production of biomass fuels also has an opportunity cost because it uses large land areas which could have been used otherwise. Accounting for the greenhouse gas emissions from biomass fuels in an environment of credits and debits creates additional challenges because there are large nonlinearities in the carbon flows over time. This paper presents some of the technical challenges of comprehensive greenhouse gas accounting and distinguishes between technical and public policy issues

Turbine interstage seal with self-balancing capability

Science.gov (United States)

Mills, Jacob A; Jones, Russell B; Sexton, Thomas D

2017-09-26

An interstage seal for a turbine of a gas turbine engine, the interstage seal having a seal carrier with an axial extending seal tooth movable with a stator of the engine, and a rotor with a seal surface that forms the interstage seal with the seal tooth, where a magnetic force produced by two magnets and a gas force produced by a gas pressure acting on the seal carrier forms a balancing force to maintain a close clearance of the seal without the seal tooth contacting the rotor seal surfaces during engine operation. In other embodiments, two pairs of magnets produce first and second magnetic forces that balance the seal in the engine.

World`s gas field and establishment of gas-specific database

Energy Technology Data Exchange (ETDEWEB)

Seong, W M [Hanyang Unversity, Seoul (Korea, Republic of)

1998-05-01

As the natural gas demand of each country of the world including Korea continuously increases, it will be very important to diversify the characteristics of import areas and import gas as well as the import method for the stable and long-term supply. This study collects information such as reserves, the possibility of production, gas composition, etc. of gas fields that are spread all over the world with areas that can be developed or simply imported under the current conditions of Korea, and analyzed the projects that can be supplied through pipelines and information on non-conventional gas field that can be estimated in the future. 35 refs., 3 figs., 28 tabs.

Emergence of Functional Specificity in Balanced Networks with Synaptic Plasticity.

Directory of Open Access Journals (Sweden)

Sadra Sadeh

2015-06-01

Full Text Available In rodent visual cortex, synaptic connections between orientation-selective neurons are unspecific at the time of eye opening, and become to some degree functionally specific only later during development. An explanation for this two-stage process was proposed in terms of Hebbian plasticity based on visual experience that would eventually enhance connections between neurons with similar response features. For this to work, however, two conditions must be satisfied: First, orientation selective neuronal responses must exist before specific recurrent synaptic connections can be established. Second, Hebbian learning must be compatible with the recurrent network dynamics contributing to orientation selectivity, and the resulting specific connectivity must remain stable for unspecific background activity. Previous studies have mainly focused on very simple models, where the receptive fields of neurons were essentially determined by feedforward mechanisms, and where the recurrent network was small, lacking the complex recurrent dynamics of large-scale networks of excitatory and inhibitory neurons. Here we studied the emergence of functionally specific connectivity in large-scale recurrent networks with synaptic plasticity. Our results show that balanced random networks, which already exhibit highly selective responses at eye opening, can develop feature-specific connectivity if appropriate rules of synaptic plasticity are invoked within and between excitatory and inhibitory populations. If these conditions are met, the initial orientation selectivity guides the process of Hebbian learning and, as a result, functionally specific and a surplus of bidirectional connections emerge. Our results thus demonstrate the cooperation of synaptic plasticity and recurrent dynamics in large-scale functional networks with realistic receptive fields, highlight the role of inhibition as a critical element in this process, and paves the road for further computational

Carbon and greenhouse gas balance of the FR-GRI crop site from 2005 to 2014

Science.gov (United States)

Loubet, Benjamin; Chammakhi, Manel; Mascher, Nicolas; Durand, Brigitte; Gueudet, Jean-Christophe; Decuq, Céline; Lecuyer, Vanessa; Laville, Patricia; Buysse, Pauline; Cellier, Pierre

2017-04-01

The carbon and greenhouse gas balance of the ICOS FR-GRI site from 2005 to 2014 is presented. The site is a wheat-barley-maize rotation with the introduction of oil-seed rape in 2012. The site receives large amounts of organic fertilization, but is shown to be a strong source of carbon to the atmosphere, especially due to the increase in the exportations of residues during the period. The exportations have increased from around 4 to around 8 t C ha-1 year-1 over the period on average except for maize for which it remained constant. In the meantime the carbon importations have increased from around 1 to around 2 t C ha-1 year-1 during the same period. Overall the field was losing around 2 t C ha-1 year-1 over the whole period but largely driven by last years (2012-2014). This would represent 17% loss of the soil carbon content in the 0-60 cm in the 2005-2014 period. The discussion focuses on explanations of these losses and possible drawbacks in the methodology. The effect of the winter intermediate crops on the carbon balance is also discussed.

Power generation from bio methane. Requirements of the EEG 2012 and balancing in gas infrastructure; Verstromung von Biomethan. Anforderungen des EEG 2012 und gaswirtschaftliche Bilanzierung

Energy Technology Data Exchange (ETDEWEB)

Herz, Steffen; Bredow, Hartwig von [von Bredow Valentin Rechtsanwaelte, Berlin (Germany)

2012-12-15

Six years ago, the first biogas infeed plant was connected to the natural gas distribution system. The infeed of biogas progressed beyond the nursery stage. The infeed of bio methane significantly is promoted by the renewable energy law. One fundamental requirement for the promotion with respect to the Renewable Energy Law is the generation of the power to be remunerated by means of the exclusive use of biomass. The Renewable Energy Law EEG 2012 contains the new requirement, that furthermore the transport of biogas from its production until removal has to be documented by means of a mass balance. Under this aspect, the authors of the contribution under consideration report on the requirements of the EEG 2012 and the balancing in gas infrastructure with respect to the power generation from biomass.

Natural gas and condensate occurrence in salt, specifically in the salt stock Gorleben-Rambow. Literature study

International Nuclear Information System (INIS)

Schneider, Ulrich

2011-01-01

The study on the natural gas and condensate occurrence in salt, specifically in the salt stock Gorleben-Rambow covers the topics development of salt deposits, salt stocks, crude oil and natural gas, gas and condensate inclusions in evaporite. Experimental data on crude oil borehole studies in Gorleben, natural gas drill holes in the salt stock Rambow, Luechow Z1 - saltstock Wustrow, gas indications, gas occurrences and gas detection are summarized.

Liquefied natural gas projects in Altamira: impacts on the prices of the natural gas; Proyectos de gas natural licuado en Altamira: impactos sobre los precios del gas natural

Energy Technology Data Exchange (ETDEWEB)

Perez Cordova, Hugo; Elizalde Baltierra, Alberto [Petroleos Mexicanos (PEMEX), (Mexico)

2004-06-15

The possible incorporation of new points of supply of natural gas to the Sistema National de Gasoductos (SNG) through the import of Liquified Natural Gas or (GNL) could cause an important modification in the national balance of supply-demand of the fuel and in its price, if large volumes are received. An analysis is presented of the possible impact that would have in the natural gas national market and in its prices the import of GNL made by the region of Altamira, Tamaulipas. [Spanish] La posible incorporacion de nuevos puntos de oferta de gas natural al Sistema Nacional de Gasoductos (SNG) a traves de la importacion de Gas Natural Licuado (GNL), podria provocar una modificacion importante en el balance oferta-demanda nacional del combustible y en su precio, si se reciben fuertes volumenes. Se presenta un analisis del posible impacto que tendria en el mercado nacional del gas natural y en sus precios la importacion de GNL realizada por la region de Altamira, Tamaulipas.

Greenhouse gas emissions and energy balance of biodiesel production from microalgae cultivated in photobioreactors in Denmark: a life-cycle modeling

DEFF Research Database (Denmark)

Monari, Chiara; Righi, Serena; Olsen, Stig Irving

2016-01-01

difficulties with both microalgae cultivation in wastewater as well as transportation and injection of waste CO2. In any way, a positive energy balance is still far from being achieved. Considerable improvements must be made to develop an environmentally beneficial microalgae biodiesel production...... of algal biodiesel from Nannochloropsis cultivated at industrial scale in photobioreactors in Denmark. Both consolidated and pioneering technologies are analyzed focusing on strengths and weaknesses which influence the performance. Based on literature data, energy balance and greenhouse gas emissions...... are determined in a comparative 'well-to-tank' Life Cycle Assessment against fossil diesel. Use of by-products from biodiesel production such as glycerol obtained from transesterification and anaerobic digestion of residual biomass are included. Different technologies and methods are considered in cultivation...

Production of inert gas for substitution of a part of the cushion gas trapped in an aquifer underground storage reservoir

International Nuclear Information System (INIS)

Berger, L.; Arnoult, J.P.

1990-01-01

In a natural gas storage reservoir operating over the different seasons, a varying fraction of the injected gas, the cushion gas, remains permanently trapped. This cushion gas may represent more than half the total gas volume, and more than 50% of the initial investment costs for the storage facility. Studies conducted by Gaz de France, backed up by experience acquired over the years, have shown that at least 20% of the cushion gas could be replaced by a less expensive inert gas. Nitrogen, carbon dioxide, or a mixture of the two, satisfy the specifications required for this inert gas. Two main production methods exist: recovery of natural gas combustion products (mixture of 88% N 2 and 12% Co 2 ) and physical separation of air components (more or less pure N 2 , depending on industrial conditions). For the specific needs of Gaz de France, the means of production must be suited to its programme of partial cushion gas substitution. The equipment must satisfy requirements of autonomy, operating flexibility and mobility. Gaz de France has tested two units for recovery of natural gas combustion products. In the first unit, the inert gas is produced in a combustion chamber, treated in a catalytic reactor to reduce nitrogen oxide content and then compressed by gas engine driven compressors. In the second unit, the exhaust gases of the compressor gas engines are collected, treated to eliminate nitrogen oxides and then compressed. The energy balance is improved. A PSA method nitrogen production unit by selective absorption of nitrogen in the air, will be put into service in 1989. The specific features of these two methods and the reasons for choosing them will be reviewed. (author). 1 fig

Fire and drought affect plant communities and the greenhouse gas balance in a Mediterranean shrubland

Science.gov (United States)

Moreno, José M.; Parra, Antonio; Dannenmann, Michael; Ramírez, David A.; Diaz-Pines, Eugenio; Tejedor, Javier; Kitzler, Barbara; Karhu, Kristina; Resco, Victor; Povoas, Luciano

2010-05-01

Predicted changes in the seasonality and amount of rainfall under a changing climate have the potential to dramatically alter ecosystem function and species composition. Moreover, in fire-prone ecosystems, the joint effects of fire and increasing aridity may create irreversible changes to the services these ecosystems provide. To understand the effects of increasing drought and fire in a Mediterranean shrubland, we implemented an automated rainfall manipulation system, with rain-out shelters which automatically fold and unfold when conditions are rainy and dry, respectively. In January 2009, we implemented five different treatments, where annual precipitation was reduced by diminishing summer rainfall from the long-term historical average, up to a 40% reduction, following IPCC scenarios. In September 2009, we uninstalled all the shelters to burn the different plots, and reinstalled the shelters immediately afterwards. In this talk, we will present the preliminary results of an integrated experiment which aims at understanding the concomitant effects of fire and different drought intensities on the species composition and greenhouse gas balance (CO2, N2O and CH4) of a Mediterranean shrubland. We observed that plant growth was more severely affected by drought in the more shallow-rooted, malacophyllous shrub (from 116 to -7.2 mg/g/d in Cistus ladanifer), than in a deeper-rooted heather (from 5.5 to 66.9 mg/g/day in Erica arborea). This growth response was mediated by species-specific differences in hydraulics, leaf morphology and photosynthetic gas exchange of each species. Analyses of changes in species composition after fire are currently undergoing. The precipitation reduction treatments exerted drought stress on CH4 oxidizing microorganisms and thus reduced the CH4 sink strength of the ecosystem during the pre-fire period. Furthermore, the net CH4 uptake at the soil-atmosphere interface was reduced by the fire for a period of at least one month. Pedosphere

Estimation of net greenhouse gas balance using crop- and soil-based approaches: Two case studies

International Nuclear Information System (INIS)

Huang, Jianxiong; Chen, Yuanquan; Sui, Peng; Gao, Wansheng

2013-01-01

The net greenhouse gas balance (NGHGB), estimated by combining direct and indirect greenhouse gas (GHG) emissions, can reveal whether an agricultural system is a sink or source of GHGs. Currently, two types of methods, referred to here as crop-based and soil-based approaches, are widely used to estimate the NGHGB of agricultural systems on annual and seasonal crop timescales. However, the two approaches may produce contradictory results, and few studies have tested which approach is more reliable. In this study, we examined the two approaches using experimental data from an intercropping trial with straw removal and a tillage trial with straw return. The results of the two approaches provided different views of the two trials. In the intercropping trial, NGHGB estimated by the crop-based approach indicated that monocultured maize (M) was a source of GHGs (− 1315 kg CO 2 −eq ha −1 ), whereas maize–soybean intercropping (MS) was a sink (107 kg CO 2 −eq ha −1 ). When estimated by the soil-based approach, both cropping systems were sources (− 3410 for M and − 2638 kg CO 2 −eq ha −1 for MS). In the tillage trial, mouldboard ploughing (MP) and rotary tillage (RT) mitigated GHG emissions by 22,451 and 21,500 kg CO 2 −eq ha −1 , respectively, as estimated by the crop-based approach. However, by the soil-based approach, both tillage methods were sources of GHGs: − 3533 for MP and − 2241 kg CO 2 −eq ha −1 for RT. The crop-based approach calculates a GHG sink on the basis of the returned crop biomass (and other organic matter input) and estimates considerably more GHG mitigation potential than that calculated from the variations in soil organic carbon storage by the soil-based approach. These results indicate that the crop-based approach estimates higher GHG mitigation benefits compared to the soil-based approach and may overestimate the potential of GHG mitigation in agricultural systems. - Highlights: • Net greenhouse gas balance (NGHGB) of

Optimal scenario balance of reduction in costs and greenhouse gas emissions for municipal solid waste management

Institute of Scientific and Technical Information of China (English)

邓娜; 张强; 陈广武; 齐长青; 崔文谦; 张于峰; 马洪亭

2015-01-01

To reduce carbon intensity, an improved management method balancing the reduction in costs and greenhouse gas (GHG) emissions is required for Tianjin’s waste management system. Firstly, six objective functions, namely, cost minimization, GHG minimization, eco-efficiency minimization, cost maximization, GHG maximization and eco-efficiency maximization, are built and subjected to the same constraints with each objective function corresponding to one scenario. Secondly, GHG emissions and costs are derived from the waste flow of each scenario. Thirdly, the range of GHG emissions and costs of other potential scenarios are obtained and plotted through adjusting waste flow with infinitely possible step sizes according to the correlation among the above six scenarios. And the optimal scenario is determined based on this range. The results suggest the following conclusions. 1) The scenarios located on the border between scenario cost minimization and GHG minimization create an optimum curve, and scenario GHG minimization has the smallest eco-efficiency on the curve;2) Simple pursuit of eco-efficiency minimization using fractional programming may be unreasonable; 3) Balancing GHG emissions from incineration and landfills benefits Tianjin’s waste management system as it reduces GHG emissions and costs.

Well-balanced Arbitrary-Lagrangian-Eulerian finite volume schemes on moving nonconforming meshes for the Euler equations of gas dynamics with gravity

Science.gov (United States)

Gaburro, Elena; Castro, Manuel J.; Dumbser, Michael

2018-06-01

In this work, we present a novel second-order accurate well-balanced arbitrary Lagrangian-Eulerian (ALE) finite volume scheme on moving nonconforming meshes for the Euler equations of compressible gas dynamics with gravity in cylindrical coordinates. The main feature of the proposed algorithm is the capability of preserving many of the physical properties of the system exactly also on the discrete level: besides being conservative for mass, momentum and total energy, also any known steady equilibrium between pressure gradient, centrifugal force, and gravity force can be exactly maintained up to machine precision. Perturbations around such equilibrium solutions are resolved with high accuracy and with minimal dissipation on moving contact discontinuities even for very long computational times. This is achieved by the novel combination of well-balanced path-conservative finite volume schemes, which are expressly designed to deal with source terms written via non-conservative products, with ALE schemes on moving grids, which exhibit only very little numerical dissipation on moving contact waves. In particular, we have formulated a new HLL-type and a novel Osher-type flux that are both able to guarantee the well balancing in a gas cloud rotating around a central object. Moreover, to maintain a high level of quality of the moving mesh, we have adopted a nonconforming treatment of the sliding interfaces that appear due to the differential rotation. A large set of numerical tests has been carried out in order to check the accuracy of the method close and far away from the equilibrium, both, in one- and two-space dimensions.

Specific radiological monitoring (SRM) in oil and gas production platforms

International Nuclear Information System (INIS)

Hairul Nizam Idris, Syed Asraf Fahlawi Wafa S.M Ghazi and Fadzley Izwan Abd Manaf

2007-01-01

Technologically enhanced naturally occurring radioactive materials (TENORM) are present in components of both oil and natural gas production facilities. TENORM can be associated with the presence of crude oil, produced water and natural gas. The radiation exposure pathways to the workers in oil and gas production are similar to those in the uranium and heavy mineral sand mining and processing industry. This paper work provides a short review on the Specific Radiological Monitoring (SRM) program were carried out at oil and gas platforms in the east cost of Peninsular Malaysia. The objective of this paper work is to observe the monitoring parameters levels and to evaluate whether these levels are exceeding the limits set by Atomic Energy Licensing Board (AELB). The monitoring results showed that the surface contamination, airborne contamination and concentration of radon and thoron are well below the set limit stipulated in LEM/TEK/30 SEM.2, except for external radiation and radioactivity concentration of sludge and scales. About 2 (2.35%) from the 85 external radiation measurements performed were found above the permissible limit. While about 11 (36.6%) and 7 (23.3%) of the 30 collected sludge and scales samples were found containing higher Ra-226 and Ra-228, respectively, than the mean concentrations in normal soils of Peninsular Malaysia. In general, it can be concluded that a few of oil and gas production platform are producing TENORM. (Author)

Energy balance of Georgia

Directory of Open Access Journals (Sweden)

Demur Chomakhidze

2016-09-01

It is shown that, traditionally, the energy balance of Georgia is in deep deficit. The suggestions for its improvement are provided in the Article. The country imports almost all amount of oil and natural gas. Electricity balance is relatively stable. In the recent years, some amount of electricity is exported to the neighboring countries. Generally, the country satisfies only 30–35% of own energy consumption by local generation, and the rest amount of resources are imported from abroad. The reason of deficit to some extent is irrational and wasteful consumption of energy resources. The article examines the organizational difficulties in drawing up energy balance of Georgia and statistical problems of recording of energy production and consumption at the initial stage of market economy.

Land-Use Implications to Energy Balances and Greenhouse Gas Emissions on Biodiesel from Palm Oil Production in Indonesia

Directory of Open Access Journals (Sweden)

Soni HARSONO

2013-06-01

Full Text Available The objectives of this study are to identify the energy balance of Indonesian palm oil biodiesel production, including the stages of land use change, transport and milling and biodiesel processing, and to estimate the amount of greenhouse gas emissions from different production systems, including large and small holder plantations either dependent or independent, located in Kalimantan and in Sumatra. Results show that the accompanied implications of palm oil biodiesel produced in Kalimantan and Sumatra are different: energy input in Sumatra is higher than in Kalimantan, except for transport processes; the input/output ratios are positive in both regions and all production systems. The findings demonstrate that there are considerable differences between the farming systems and the locations in net energy yields (43.6 to 49.2 GJ t-1 biodiesel yr-1 as well as greenhouse gas emissions (1969.6 to 5626.4 kg CO2eq t-1 biodiesel yr-1. The output to input ratios are positive in all cases. The largest greenhouse gas emissions result from land use change effects, followed by the transesterification, fertilizer production, agricultural production processes, milling and transportation. Ecosystem carbon payback times range from 11 to 42 years.

Net soil respiration and greenhouse gas balance along a sequence of forest disturbance to smallholder rubber and oil palm plantations in Sumatra

Science.gov (United States)

Khusyu Aini, Fitri; Hergoualc'h, Kristell; Smith, Jo; Verchot, Louis; Martius, Christopher

2017-04-01

The rapid increase in demand for land to establish oil palm and rubber plantations has led to the conversion of forests, with potential impacts on greenhouse gas emissions and on climate change. This study evaluates the net greenhouse gas balance following forest change to other land uses, i.e. one year rubber plantation, twenty-year rubber plantation and eight year oil palm plantation on Sumatran mineral soils. None of the plantations had ever been fertilized previously. During this study they were fertilized to provide nitrogen at the recommended rate used by farmers (33.3 kg N ha-1 y-1). The ecosystem stores carbon in litterfall, standing litter biomass (undergrowth vegetation, leaves, twigs, litter on the soil surface), soil organic matter, root biomass, and standing tree biomass. It releases carbon to the atmosphere through soil respiration fluxes, negative values indicating that carbon is stored by the land use change and positive values indicating emissions to the atmosphere. Net soil respiration was assessed using a mass balance approach: standing litter and tree biomass were measured once; the rate of carbon accumulation from standing litter and tree biomass was calculated by dividing the stock by the age of plantation or the time since logging started in the disturbed forest. The carbon accumulation in standing litter, tree biomass in the forest and soil organic matter for all land-uses was estimated from available in the literature. Root biomass for each land-use system was calculated using the root:shoot ratio. The net soil respiration of carbon dioxide from the forest, disturbed forest, one year rubber plantation, twenty-year rubber plantation and oil palm plantation were calculated to be -6 (± 5), 12 (± 6), 11 (± 15), 10 (± 5), 39 (± 7) Mg ha-1 y-1, respectively. Soil nitrous oxide, methane and litterfall were measured for 14 months and respiration fluxes were measured for 5 months across land uses and different seasons. The measured emissions of

Investigating onychophoran gas exchange and water balance as a means to inform current controversies in arthropod physiology.

Science.gov (United States)

Clusella-Trullas, Susana; Chown, Steven L

2008-10-01

Several controversies currently dominate the fields of arthropod metabolic rate, gas exchange and water balance, including the extent to which modulation of gas exchange reduces water loss, the origins of discontinuous gas exchange, the relationship between metabolic rate and life-history strategies, and the causes of Palaeozoic gigantism. In all of these areas, repeated calls have been made for the investigation of groups that might most inform the debates, especially of taxa in key phylogenetic positions. Here we respond to this call by investigating metabolic rate, respiratory water loss and critical oxygen partial pressure (Pc) in the onychophoran Peripatopsis capensis, a member of a group basal to the arthropods, and by synthesizing the available data on the Onychophora. The rate of carbon dioxide release (VCO2) at 20 degrees C in P. capensis is 0.043 ml CO2 h(-1), in keeping with other onychophoran species; suggesting that low metabolic rates in some arthropod groups are derived. Continuous gas exchange suggests that more complex gas exchange patterns are also derived. Total water loss in P. capensis is 57 mg H2O h(-1) at 20 degrees C, similar to modern estimates for another onychophoran species. High relative respiratory water loss rates ( approximately 34%; estimated using a regression technique) suggest that the basal condition in arthropods may be a high respiratory water loss rate. Relatively high Pc values (5-10% O2) suggest that substantial safety margins in insects are also a derived condition. Curling behaviour in P. capensis appears to be a strategy to lower energetic costs when resting, and the concomitant depression of water loss is a proximate consequence of this behaviour.

Component greenhouse gas fluxes and radiative balance from two deltaic marshes in Louisiana: Pairing chamber techniques and eddy covariance

Science.gov (United States)

Krauss, Ken W.; Holm, Guerry O.; Perez, Brian C.; McWhorter, David E.; Cormier, Nicole; Moss, Rebecca; Johnson, Darren; Neubauer, Scott C; Raynie, Richard C

2016-01-01

Coastal marshes take up atmospheric CO2 while emitting CO2, CH4, and N2O. This ability to sequester carbon (C) is much greater for wetlands on a per-area basis than from most ecosystems, facilitating scientific, political, and economic interest in their value as greenhouse gas sinks. However, the greenhouse gas balance of Gulf of Mexico wetlands is particularly understudied. We describe the net ecosystem exchange (NEEc) of CO2 and CH4 using eddy covariance (EC) in comparison with fluxes of CO2, CH4, and N2O using chambers from brackish and freshwater marshes in Louisiana, USA. From EC, we found that 182 g C m-2 y-1 was lost through NEEc from the brackish marsh. Of this, 11 g C m-2 y-1 resulted from net CH4 emissions and the remaining 171 g C m-2 y-1 resulted from net CO2 emissions. In contrast, -290 g C m2 y-1 was taken up through NEEc by the freshwater marsh, with 47 g C m-2 y-1 emitted as CH4 and -337 g C m-2 y-1 taken up as CO2. From chambers, we discovered that neither site had large fluxes of N2O. Sustained-flux greenhouse gas accounting metrics indicated that both marshes had a positive (warming) radiative balance, with the brackish marsh having a substantially greater warming effect than the freshwater marsh. That net respiratory emissions of CO2 and CH4 as estimated through chamber techniques were 2-4 times different from emissions estimated through EC requires additional understanding of the artifacts created by different spatial and temporal sampling footprints between techniques.

Predictive assessment of the Ukrainian power industry fuel balance structure progress

Directory of Open Access Journals (Sweden)

Alexander P. Voinov

2014-12-01

Full Text Available The existing structure of the fuel balance in Ukraine does largely determine high prices of such energy products as the electricity and the heat. The main reason lies in the fact that approximately 40% of the fuel balance represents the expensive imported liquid and gaseous fuels. Of course, such balance structure significantly affects the energy security of Ukraine. The article analyzes the three main directions of this situation possible normalization: replacing the imported gas with relatively inexpensive domestic coal burned at boilers and innovative coal-fired burner systems, especially in the low-temperature boilers with fluidized bed furnaces; replacement of imported fuel with respectively cheap pyrolysis gas obtained from the domestic low-grade brown coal; organization of domestic production of shale gas, which industrial production is scheduled for 2020. These promising directions of the national energetics’ fuel balance development can be considered as a priority part of the national tasks of increasing the country’s energy independence.

Management of natural gas supply reliability and modulation in France

International Nuclear Information System (INIS)

Dupas, D.

1995-01-01

France imports most of its gas, and demand for gas varies considerably between summer and winter. Faced with insufficient flexibility in its supply contracts to deal with the gas balance, Gaz de France decided to develop a policy based on combined and consistent use of a large-scale underground storage system, a suspendable clientele, and a rate policy to maintain the balance. It was the integrated character of the company that makes it possible to optimize the arrangement of these adjustment facilities. Most of the seasonal modulation is taken up by underground storage in water tables, and the peak cold complement comes from salt dome storage. Underground storage also contributes, as does the suspendable clientele, to supply reliability, with a specific quality due to their speed and versatility of use. The prime purpose of the suspendable clientele portfolio is rather to respond to supply failures, but the demand too, during periods of extreme cold, is reduced by curtailing deliveries whose contractual suspension notice time is short. (author). 3 figs

Balancing the supply mix to meet tomorrow's energy needs

International Nuclear Information System (INIS)

Wiggin, M.

2004-01-01

This presentation emphasized the need to balance the power supply mix to ensure future energy needs. A balanced supply includes generation supply options that include renewable energy sources, natural gas, oil or coal. The role of combined heat and power (CHP) and district energy in this supply mix is considered to be a potential generation solution. The challenge facing Ontario's Independent Electricity Market Operator (IMO) is to balance supply and demand, phase out coal, promote renewables, diminish demand and determine the new role for natural gas. A graph by the National Energy Board depicting Canada's energy future and scenarios for supply and demand to 2025 indicates that gas yields from the Western Canada Sedimentary Basin are declining. It is expected that with growing demands for natural gas, prices will remain high and there will be a need for new generation capacity. The viable options for energy supply include a re-examination of the district energy advantage through industrial waste heat, biomass and other renewables, and the integration of industrial and community energy systems. Other options include the continued recognition of distributed generation in the form of combined heat and power. 4 figs

API Specification Q1: The quality system specification for the oil and gas industry

International Nuclear Information System (INIS)

Peurifoy, C.K.

1994-01-01

The Oil and Gas Production Industry began using the American Petroleum Institute's Specification Q1, ''Specification for Quality Programs'' (1st Edition, January 1, 1985) in late 1984. The generic ISO 9000 Series Standards, ''Quality management and quality assurance standards,'' were developed at about the same time and were published for public use in 1987. By late 1989 and into the early nineties, the formation of the European Economic Community and the issuance of the EC Procurement Directives sparked a rush by companies worldwide to comply with all the requirements necessary to do business in Europe. The ensuing ''ISO Mania'' has created a windfall for any company providing ISO 9000 quality system certification, consulting, training and almost anything to do with ISO 9000. It is difficult to miss one of the hundreds of newspaper and trade magazine articles promoting the ISO 9000 Quality Standards for use in almost every industry. This paper discusses the latest developments of both the lesser known API Spec Q1 and the much publicized ISO 9001 as well as discusses some of the similarities and differences between them and possible future trends. It also reviews some of the strengths and weaknesses of both documents to support the sentiment that API Spec Q1, in conjunction with the API Monogram Program, is the best quality standard for use in ordering equipment, materials and services for the Oil and Gas Industry

Economic balance sheet of a natural gas vehicle fleet

International Nuclear Information System (INIS)

Anon.

1996-01-01

Natural gas fuels for vehicles bear an important and variable additional cost which corresponds to the cost for compression. This short paper gives a cost-benefit comparative estimation of the m 3 of natural gas cost when the FUELMAKER and the CIRRUS compressors are used, respectively. A comparative economic estimation between petrol and natural gas for vehicles is given for two Renault vehicles. (J.S.)

Natural gas marketing II

International Nuclear Information System (INIS)

Anon.

1988-01-01

This book covers all aspects of gas marketing, from the basic regulatory structure to the latest developments in negotiating agreements and locating markets. Topics include: Federal regulation of the gas industry; Fundamentals of gas marketing contracts; FERC actions encouraging competitive markets; Marketing conditions from the pipelines' perspective; State non-utility regulation of natural gas production, transportation, and marketing; Natural gas wellhead agreements and tariffs; Natural gas processing agreements; Effective management of producer's natural gas contracts; Producer-pipeline litigation; Natural gas purchasing from the perspective of industrial gas users; Gas marketing by co-owners: problems of disproportionate sales, gas balancing, and accounting to royalty owners; Alternatives and new directions in marketing

Regional specific mean expiratory gas flow from Slmsub(Kr) equilibrium inhalation data

International Nuclear Information System (INIS)

Hamilton, D.; Causer, D.A.; McIntosh, J.A.; Godfrey, K.R.

1985-01-01

A new method of analysing the data available from routine sup(81m) Kr equilibrium inhalation investigations has been developed. The data for analysis are acquired from a gamma camera in the form of a sequential series of images from which multiple breath activity-time curves are generated for eight regions in the lung. The method is based on a description of the behaviour of the radioactive gas in the lung using a mathematical model. Values of specific mean expiratory gas flow, that is mean expiratory gas flow per unit lung volume, are calculated from the application of the model to the expiratory phase only only of a single breath activity-time curve which is generated from the multiple breath activity-time curve using post-acquisition gating. This method overcomes the problem of non-uniform inspiratory concentration of tracer gas experienced in previously reported techniques of analysing inhalation data obtained using poorly soluble radioactive gases. The model is shown, in simulation studies, to be an adequate description of the behaviour of radioactive gas in the lung and the analysis technique is shown, in clinical studies, to be both reproducible and sensitive to disease state. (orig.)

Bifuel coal-gas combined cycles

International Nuclear Information System (INIS)

Chmielniak, Tadeusz; Kotowicz, Janusz; Lyczko, Jacek

1997-01-01

This paper describes basic ways of realization of bi fuel cool-gas combined cycles. The criterion of classification of the systems specification is a joint of the gas pail with the steam part: a) The gas turbine flue gases are introduced into the steam boiler combustion chamber (the serial, hot wind box). b) Bypass of the beat exchangers at the steam turbine unit and/or the steam boiler, by use the waste heat exchangers, or waste boiler at the gas turbine unit (the parallel-coupled). c) The mixed, it's a combination of the two upper. The analysis of the parallel system has been specially presented. In derived formulas for the total efficiency of the bi fuel parallel combined cycle balance equations have been used. This formulas can be used for planning new combined cycle power plants and for modernization existing steam power plants. It was made a discussion about influence of the ratio the gas and the steam turbine electric power on the cycle efficiency in care of the full and the part load of the bi fuel combined cycle power plant. The various systems of the joint of the gas part with the steam part have been examined. The selected results of the calculations have been attached. The models and the numerical simulations have been based on data from the existing steam power plants and real gas turbine units. (Author)

Natural gas projects, strategies and economics

International Nuclear Information System (INIS)

Hamaide, G.

2000-01-01

This article summarizes the content of some of the posters presented during the WOC 9 working committee of the CMG 2000 worldwide gas congress: natural gas in the new worldwide energy balance; eastern Russia: the last gas projects; the new underwater technologies and the availability of natural gas. (J.S.)

The gas industry in Spain

International Nuclear Information System (INIS)

Jego, H.

1999-01-01

This short presentation of the Spanish gas industry looks at the industry's different players including Gas Natural, which controls almost all of the gas distribution in Spain. Natural gas, almost all of which is imported, accounts for an ever-growing share in the country's energy balance and has undergone great developments, particularly in industry and in thermal generating plants. (author)

Wii Fit Balance Board Playing Improves Balance and Gait in Parkinson Disease

Science.gov (United States)

Mhatre, Priya V.; Vilares, Iris; Stibb, Stacy M.; Albert, Mark V.; Pickering, Laura; Marciniak, Christina M.; Kording, Konrad; Toledo, Santiago

2014-01-01

Objective To assess the effect of exercise training by using the Nintendo Wii Fit video game and balance board system on balance and gait in adults with Parkinson disease (PD). Design A prospective interventional cohort study. Setting An outpatient group exercise class. Participants Ten subjects with PD, Hoehn and Yahr stages 2.5 or 3, with a mean age of 67.1 years; 4 men, 6 women. Interventions The subjects participated in supervised group exercise sessions 3 times per week for 8 weeks by practicing 3 different Wii balance board games (marble tracking, skiing, and bubble rafting) adjusted for their individualized function level. The subjects trained for 10 minutes per game, a total of 30 minutes training per session. Main Outcome Measurements Pre-and postexercise training, a physical therapist evaluated subjects’ function by using the Berg Balance Scale, Dynamic Gait Index, and Sharpened Romberg with eyes open and closed. Postural sway was assessed at rest and with tracking tasks by using the Wii balance board. The subjects rated their confidence in balance by using the Activities-specific Balance Confidence scale and depression on the Geriatric Depression Scale. Results Balance as measured by the Berg Balance Scale improved significantly, with an increase of 3.3 points (P = .016). The Dynamic Gait Index improved as well (mean increase, 2.8; P = .004), as did postural sway measured with the balance board (decreased variance in stance with eyes open by 31%; P = .049). Although the Sharpened Romberg with eyes closed increased by 6.85 points and with eyes opened by 3.3 points, improvements neared significance only for eyes closed (P = .07 versus P = .188). There were no significant changes on patient ratings for the Activities-specific Balance Confidence (mean decrease, −1%; P = .922) or the Geriatric Depression Scale (mean increase, 2.2; P = .188). Conclusions An 8-week exercise training class by using the Wii Fit balance board improved selective measures of

Comparison of the Berg Balance Scale and Fullerton Advanced Balance Scale to predict falls in community-dwelling adults.

Science.gov (United States)

Jeon, Yong-Jin; Kim, Gyoung-Mo

2017-02-01

[Purpose] The purpose of this study was to investigate and compare the predictive properties of Berg Balance Scale and Fullerton Advanced Balance Scales, in a group of independently-functioning community dwelling older adults. [Subjects and Methods] Ninety-seven community-dwelling older adults (male=39, female=58) who were capable of walking independently on assessment were included in this study. A binary logistic regression analysis of the Berg Balance Scale and Fullerton Advanced Balance Scale scores was used to investigate a predictive model for fall risk. A receiver operating characteristic analysis was conducted for each, to determine the cut-off for optimal levels of sensitivity and specificity. [Results] The overall prediction success rate was 89.7%; the total Berg Balance Scale and Fullerton Advanced Balance Scale scores were significant in predicting fall risk. Receiver operating characteristic analysis determined that a cut-off score of 40 out of 56 on the Berg Balance Scale produced the highest sensitivity (0.82) and specificity (0.67), and a cut-off score of 22 out of 40 on the Fullerton Advanced Balance Scale produced the highest sensitivity (0.85) and specificity (0.65) in predicting faller status. [Conclusion] The Berg Balance Scale and Fullerton Advanced Balance Scales can predict fall risk, when used for independently-functioning community-dwelling older adults.

Henry Hub and national balancing point prices: what will be the international gas price reference?

International Nuclear Information System (INIS)

Mazighi, A.E.H.

2005-01-01

One of the lessons in the history of international trade in commodities is the emergence - sooner or later - of an international price reference, most commonly known as an international marker price. In the area of oil, West Texas Intermediate (WTI) plays the role of a marker for sour crudes traded in the Atlantic basin. Brent oil fulfils this function for sweet crudes traded in Europe. Another important aspect in the area of global commodities is that the emergence of a marker price is not always necessarily related to the relative share of production of exports of the commodity, but primarily to the existence of an organized market for this commodity. Today, while international gas trade is intensifying, we still lack an international price reference for this commodity. This is due to the fact that the international trade of natural gas is still highly regionalized. It is also due to the fact that most gas markets are still regulated. Nevertheless, deregulation efforts have been implemented in both developed (the United States, the United Kingdom, continental Europe, Korea) and developing countries (Brazil, Chile) and have led to new market structures based on more competition in all segments of the gas chain, except transportation. In the meantime, price structures based on supply and demand principles are supposed to have emerged in the US and UK markets in the 1990s as a result of the implementation of deregulation measures. Today, the US gas market, which represents more than 660 billion cubic metres per year of consumption and the UK gas market, which is close to 100 bcm annually, are considered mature enough to make the principles of supply and demand operate inside these markets. In fact, the Henry Hub (HH) price, which is determined at a physical location in Louisiana, US, and the national balancing point (NBP) price, which is determined somewhere inside the national transmission system (NTS), without any precise location, are considered as potential

Natural gas consumption within GRTgaz@s balancing zones - Year 2009

International Nuclear Information System (INIS)

2010-01-01

GRTgaz is a European leader in natural gas transmission, a world expert in gas transmission networks and systems, and an operator firmly committed to the energy transition. It owns and operates the gas transmission network throughout most of France and it manages the transmission network in Germany, thereby helping to ensure correct operation of the French and European gas market. It contributes to the energy security of regional supply systems and performs a public service mission to ensure the continuity of consumer supply. This document presents some key figures about GRTgaz activity in 2009: Gross and climate-adjusted consumption on GRTgaz's territory, Quantities of natural gas transported by GRTgaz in 2008 and 2009

A model-based analysis of the implications of shale gas developments for the European gas market

Energy Technology Data Exchange (ETDEWEB)

De Joode, J.; Plomp, A.J.; Ozdemir, O. [ECN Policy Studies, Petten (Netherlands)

2012-04-15

Shale gas in Europe could potentially be a big thing, especially in particular regions. Whereas test drillings need to confirm the technical recoverability of deposits and further research is needed on the environmental and safety aspects of shale gas production, this paper illustrates that shale gas developments may have substantial implications for regional gas balances, gas flows, and infrastructure requirements throughout Europe in the next decades.

Definitions and guidelines for classification of oil and gas reserves

Energy Technology Data Exchange (ETDEWEB)

DeSorcy, G.J.; Warne, G.A.; Ashton, B.R.; Campbell, G.R.; Collyer, D.R.; Drury, J.; Lang, R.V.; Robertson, W.D.; Robinson, J.G.; Tutt, D.W

1993-05-01

The unpredictability of estimating reserves of oil and gas has made it imperative to develop a universal set of definitions and guidelines for calculating and classifying reserves. A committee of representatives from the oil and gas industry, consulting firms, industry associations, regulatory agencies, government, and financial organizations in Canada has prepared definitions of oil and gas resources and reserves, as well as a recommended classification system for those reserves. The committee believes these definitions and guidelines are suitable for use with respect to all types of oil and gas and related substances, including offshore situations and oil sands. Both deterministic and probabilistic methods are presented, as well as guidelines for specific methods including the volumetric, material balance, decline curve analysis, and reservoir simulation methods. The guidelines also consider reserves from improved recovery projects and reserves of natural gas liquids and sulfur. A glossary of terms is appended. 14 figs.

Energy balance of Flanders 1995: Disparity method; Energiebalans Vlaanderen 1995: verschilmethode

Energy Technology Data Exchange (ETDEWEB)

Aernouts, K.; Moorkens, I.

1998-10-01

In this report the energy balance is presented, together with an estimation of the CO2-emissions. Apart from data about 1995, comparable data about the 1990-1994 period are presented in order to give a picture of the evolution of both the energy consumption and the CO2-emissions in Flanders. The energy balance is calculated by subtracting the energy balances of the Walloon and Brussels region from the Belgian one. Afterward, these results were corrected as far as specific Flemish data were available. For the calculation of the CO2-emissions the revised 1996 IPCC guidelines for national greenhouse gas inventories were used.In 1995, the primary energy consumption in Flanders was 1 502 PJ, the gross inland consumption was 1 294 PJ. The final energy consumption amounted 948 PJ. The total CO2-emission was 71 790 kton (excluding emissions from international aviation and marine bunkering). Compared to 1990, the gross inland consumption had increased some 12.8 per cent by 1995, the final energy consumption 17.8 per cent and the CO2-emissions 7.4 per cent.

Comparison of two balance training programs on balance in community dwelling older adults

Directory of Open Access Journals (Sweden)

Shefali Walia

2016-09-01

Full Text Available Impaired balance has been associated with an increased risk for falls and a resulting increase in the mortality rate of elder people. Thus, balance-training interventions have an important place in fall prevention. This study was designed with the purpose of identifying the appropriate balance-training program for community dwelling elderly adults with an active lifestyle. A sample of 70 elderly adults were randomly allocated into two groups: group 1 (n=35 received general balance and mobility exercise; group 2 (n=35 received specific balance strategy training. The intervention consisted of 5 sessions/week for 4 weeks. The outcome measures were Timed up and go test (TUGT and Berg balance scale (BBS. An inter-group (2-way mixed model analysis of co-variance and intra-group (repeated measures analysis was done to find the change in balance scores. After the intervention, the TUGT scores in group 1 were, mean=10.38 s, standard deviation (SD=1.59 s and in group 2 were, mean=9.27 s, SD=1.13 s. Post training, BBS scores for group 1 were, mean=54.69, SD=1.13, and for group 2 were, mean=55.57, SD =0.56. There was a significant group × time effect for TUGT and BBS score. All the subjects showed significant changes in balance scores after balance training interventions. The subjects who participated in the specific balance-strategy training significantly improved their functional mobility, as shown on the TUGT, compared to the general training group.

Wnt signaling balances specification of the cardiac and pharyngeal muscle fields

Science.gov (United States)

Mandal, Amrita; Holowiecki, Andrew; Song, Yuntao Charlie; Waxman, Joshua S.

2017-01-01

Canonical Wnt/β-catenin (Wnt) signaling plays multiple conserved roles during fate specification of cardiac progenitors in developing vertebrate embryos. Although lineage analysis in ascidians and mice has indicated there is a close relationship between the cardiac second heart field (SHF) and pharyngeal muscle (PM) progenitors, the signals underlying directional fate decisions of the cells within the cardio-pharyngeal muscle field in vertebrates are not yet understood. Here, we examined the temporal requirements of Wnt signaling in cardiac and PM development. In contrast to a previous report in chicken embryos that suggested Wnt inhibits PM development during somitogenesis, we find that in zebrafish embryos Wnt signaling is sufficient to repress PM development during anterior-posterior patterning. Importantly, the temporal sensitivity of dorso-anterior PMs to increased Wnt signaling largely overlaps with when Wnt signaling promotes specification of the adjacent cardiac progenitors. Furthermore, we find that excess early Wnt signaling can cell autonomously promote expansion of the first heart field (FHF) progenitors at the expense of PM and SHF within the anterior lateral plate mesoderm (ALPM). Our study provides insight into an antagonistic developmental mechanism that balances the sizes of the adjacent cardiac and PM progenitor fields in early vertebrate embryos. PMID:28087459

How balance task-specific training contributes to improving physical function in older subjects undergoing rehabilitation following hip fracture: a randomized controlled trial.

Science.gov (United States)

Monticone, Marco; Ambrosini, Emilia; Brunati, Roberto; Capone, Antonio; Pagliari, Giulia; Secci, Claudio; Zatti, Giovanni; Ferrante, Simona

2018-03-01

To evaluate the efficacy of a rehabilitation programme including balance task-specific training in improving physical function, pain, activities of daily living (ADL), balance and quality of life in subjects after a hip fracture. Randomized controlled trial. A total of 52 older subjects selected for internal fixation due to extra-capsular hip fracture were randomized to be included in an experimental ( n = 26) and control group ( n = 26). The experimental group underwent a rehabilitation programme based on balance task-specific training. The control group underwent general physiotherapy, including open kinetic chain exercises and walking training. Both groups individually followed programmes of 90-minute sessions five times/week for three weeks. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), a Pain Numerical Rating Scale, the Berg Balance Scale, the Functional Independence Measure and the 36-item Short-Form Health Survey. The participants were evaluated before and after training, and after 12 months. Significant effects of time, group and time × group were found for all outcome measures in favour of the experimental group. A clinically important between-group difference of 25 points was achieved after training and at follow-up in terms of the primary outcome (WOMAC function before treatment, after treatment and at follow-up was 84.8 (3.7), 39.8 (4.9) and 35.7 (6.2) for the experimental group and 80.9 (5.7), 65.2 (7.1) and 61.0 (11.1) for the control group). An inpatient rehabilitation programme based on balance task-specific training is useful in improving physical function, pain, ADL and quality of life in older patients after hip fracture.

Configuration-specific kinetic theory applied to an ideal binary gas mixture.

Science.gov (United States)

Wiseman, Floyd L

2006-10-05

This paper is the second in a two-part series dealing with the configuration-specific analyses for molecular collision events of hard, spherical molecules at thermal equilibrium. The first paper analyzed a single-component system, and the reader is referred to it for the fundamental concepts. In this paper, the expressions for the configuration-specific collision frequencies and the average line-of-centers collision angles and speeds are derived for an ideal binary gas mixture. The analyses show that the average line-of-centers quantities are all dependent upon the ratio of the masses of the two components, but not upon molecular size. Of course, the configuration-specific collision frequencies do depend on molecular size. The expression for the overall binary collision frequency is a simple sum of the configuration-specific collision frequencies and is identical to the conventional expression.

Influence of different storage times and temperatures on blood gas and acid-base balance in ovine venous blood.

Science.gov (United States)

Hussein, H A; Aamer, A A

2013-01-01

The present study was designed to investigate the effects of storage temperature and time on blood gas and acid-base balance of ovine venous blood. Ten clinically healthy sheep were used in this study. A total number of 30 blood samples, were divided into three different groups, and were stored in a refrigerator adjusted to +4 ºC (Group I, n = 10), at RT of about 22-25 ºC (Group II, n = 10) and in an incubator adjusted to 37 ºC (Group III, n = 10) for up to 48 h. Blood samples were analysed for blood gas and acid-base indices at 0, 1, 2, 3, 4, 5, 6, 12, 24 and 48 h of storage. In comparison to the baseline value (0), there were significant decreases of blood pH of samples stored at RT and in the incubator after 1 h (ppO2 values were significantly higher for Group I after 2 h and for Groups II and III after 1 h (preference range and it may be of clinical diagnostic use for up to 6 h.

EFFECT OF SPECIFIC BALANCE STRATEGY TRAINING PROGRAMME ON BALANCE IN INSTITUTIONALIZED ELDERLY POPULATION

OpenAIRE

Muzaffar Mairaj; Hamdani Nusrat; Walia Shefali

2015-01-01

Background: Balance emerges from the interaction of multiple systems that are organized to meet functional task goals and that are constrained by environmental context, but is often compromised with advancing age. At least 30% of older people experience decline in physical activity after entry into residential care. Participation in activity is more difficult for older people because of fear, lack of motivation, depression and poor understanding of the long term benefits of physical activity....

Wii Fit balance board playing improves balance and gait in Parkinson disease.

Science.gov (United States)

Mhatre, Priya V; Vilares, Iris; Stibb, Stacy M; Albert, Mark V; Pickering, Laura; Marciniak, Christina M; Kording, Konrad; Toledo, Santiago

2013-09-01

To assess the effect of exercise training by using the Nintendo Wii Fit video game and balance board system on balance and gait in adults with Parkinson disease (PD). A prospective interventional cohort study. An outpatient group exercise class. Ten subjects with PD, Hoehn and Yahr stages 2.5 or 3, with a mean age of 67.1 years; 4 men, 6 women. The subjects participated in supervised group exercise sessions 3 times per week for 8 weeks by practicing 3 different Wii balance board games (marble tracking, skiing, and bubble rafting) adjusted for their individualized function level. The subjects trained for 10 minutes per game, a total of 30 minutes training per session. Pre-and postexercise training, a physical therapist evaluated subjects' function by using the Berg Balance Scale, Dynamic Gait Index, and Sharpened Romberg with eyes open and closed. Postural sway was assessed at rest and with tracking tasks by using the Wii balance board. The subjects rated their confidence in balance by using the Activities-specific Balance Confidence scale and depression on the Geriatric Depression Scale. Balance as measured by the Berg Balance Scale improved significantly, with an increase of 3.3 points (P = .016). The Dynamic Gait Index improved as well (mean increase, 2.8; P = .004), as did postural sway measured with the balance board (decreased variance in stance with eyes open by 31%; P = .049). Although the Sharpened Romberg with eyes closed increased by 6.85 points and with eyes opened by 3.3 points, improvements neared significance only for eyes closed (P = .07 versus P = .188). There were no significant changes on patient ratings for the Activities-specific Balance Confidence (mean decrease, -1%; P = .922) or the Geriatric Depression Scale (mean increase, 2.2; P = .188). An 8-week exercise training class by using the Wii Fit balance board improved selective measures of balance and gait in adults with PD. However, no significant changes were seen in mood or

Power balance limit in collective ion acceleration

International Nuclear Information System (INIS)

Olson, C.L.

1978-01-01

The power balance limit to the IREB beam front propagation velocity, as first applied to the problem of collective ion acceleration by Olson in 1973, is investigated in view of recent data of Ecker and Putnam. The beam front velocity β/sub f/c as a function of IREB impedance Z is given, showing the dependence on the power balance limit, the ionization front velocity, and the runaway cutoff. The Olson theory predictions, with no fitted parameters, are shown to be in agreement with the data. Further comparisons of β/sub f/ with respect to the IREB electron energy, the IREB current, and the neutral gas pressure are given. Various forms for the power balance limit are discussed; it is shown that inclusion of the secondary electron power loss term results in an essentially negligible correction to β/sub f/ for typical data parameters. The power balance limit used by Ecker and Putnam is shown to be simply a 3-parameter curve fit, wherein the fitted parameters must exceed their allowed physical values to obtain a reasonable fit for β/sub f/ vs Z. Further, it is shown that this curve fitting leads to serious disagreements with other aspects of the data. It is concluded that the original Olson theory adequately accounts for the data, and that the power balance limit for IREB/gas data is typically not significant except for very small values of Z

Natural gas marketing and transportation

International Nuclear Information System (INIS)

Anon.

1991-01-01

This book covers: Overview of the natural gas industry; Federal regulation of marketing and transportation; State regulation of transportation; Fundamentals of gas marketing contracts; Gas marketing options and strategies; End user agreements; Transportation on interstate pipelines; Administration of natural gas contracts; Structuring transactions with the nonconventional source fuels credit; Take-or-pay wars- a cautionary analysis for the future; Antitrust pitfalls in the natural gas industry; Producer imbalances; Natural gas futures for the complete novice; State non-utility regulation of production, transportation and marketing; Natural gas processing agreements and Disproportionate sales, gas balancing, and accounting to royalty owners

Importance of balancing membrane and electrode water in anion exchange membrane fuel cells

Science.gov (United States)

Omasta, T. J.; Wang, L.; Peng, X.; Lewis, C. A.; Varcoe, J. R.; Mustain, W. E.

2018-01-01

Anion exchange membrane fuel cells (AEMFCs) offer several potential advantages over proton exchange membrane fuel cells (PEMFCs), most notably to overcome the cost barrier that has slowed the growth and large scale implementation of fuel cells for transportation. However, limitations in performance have held back AEMFCs, specifically in the areas of stability, carbonation, and maximum achievable current and power densities. In order for AEMFCs to contend with PEMFCs for market viability, it is necessary to realize a competitive cell performance. This work demonstrates a new benchmark for a H2/O2 AEMFC with a peak power density of 1.4 W cm-2 at 60 °C. This was accomplished by taking a more precise look at balancing necessary membrane hydration while preventing electrode flooding, which somewhat surprisingly can occur both at the anode and the cathode. Specifically, radiation-grafted ETFE-based anion exchange membranes and anion exchange ionomer powder, functionalized with benchmark benzyltrimethylammonium groups, were utilized to examine the effects of the following parameters on AEMFC performance: feed gas flow rate, the use of hydrophobic vs. hydrophilic gas diffusion layers, and gas feed dew points.

Tax balance in agribusiness as a type of special balance

Directory of Open Access Journals (Sweden)

Milojević Ivan

2015-01-01

Full Text Available The tendency of continuous compounding of business processes inevitably leads to application of increasingly complex instruments for the purposes of financial reporting in agribusiness. In this system the existential place and role of individual elements that alter the existing and acquire new functions comes into question. Balancing implies a regulated and consistent system in which every change leads to the creation of new relations and changing already established relationships. In this regard, in this paper we will focus on the place and role of tax balance in the group of special balances in agribusiness, as a very significant group of accounting instruments. Displaying information for users and situations in which they are used, balances gain their place in this classification. For the purposes of applying financial instruments, referring primarily to balances in agribusiness, it is necessary to know the way of their classification according to their functions. From this aspect, tax balance in agribusiness is a specific report, both in terms of its formal and material structure, which gives it the basis to belong to ordinary as well as special types of balances in agribusiness.

An open circuit balance respirometer for bioenergetic studies of fish growth

NARCIS (Netherlands)

Hogendoorn, H.; Korlaar, van F.; Bosch, H.

1981-01-01

A description is given of an open circuit balance respirometer for bioenergetic studies of fish growth using indirect calorimetry. The installation was designed to enable the determination of gas and matter balances of fish, including air breathing species, during prolonged experimental periods.

Short-term outlook for natural gas and natural gas liquids to 2006 : an energy market assessment

International Nuclear Information System (INIS)

2005-10-01

In recent years, natural gas markets in North America have seen a close balance between supply and demand, resulting in high and volatile natural gas prices. The National Energy Board monitors the supply of all energy commodities in Canada along with the demand for Canadian energy commodities in domestic and export markets. This is the NEB's first energy market assessment report that presents a combined short-term analysis and outlook of natural gas and natural gas liquids (NGLs), such as ethane, propane and butane. It provides comprehensive information on the complexity of natural gas and NGL industries and highlights recent developments and topical issues. As a major producer of natural gas, western Canada has a correspondingly large natural gas processing capability that was developed specifically to extract NGLs. A world-scale petrochemical industry was developed in Alberta to convert NGLs into even higher valued products such as ethylene. Since NGLs in Canada are sourced mostly from natural gas, changes to the supply and demand for natural gas would impact NGL supply. This report addressed the issue of commodity prices with reference to crude oil, natural gas and NGL prices. Natural gas supply in terms of North American production and natural gas from coal (NGC) was also reviewed along with natural gas demand for residential and commercial heating, industrial use, power generation, and enhanced recovery for oil sand operations. There are about 692 gas plants in Canada that process raw natural gas into marketable gas and NGLs. Most are small field plants that process raw natural gas production to remove impurities such as sulphur, water and other contaminants. This report also discussed this infrastructure, with reference to field plants, straddle plants, pipelines, distribution and storage, including underground NGL storage. 3 tabs., 27 figs., 5 appendices

Probabilistic modelling and uncertainty analysis of flux and water balance changes in a regional aquifer system due to coal seam gas development.

Science.gov (United States)

Sreekanth, J; Cui, Tao; Pickett, Trevor; Rassam, David; Gilfedder, Mat; Barrett, Damian

2018-09-01

Large scale development of coal seam gas (CSG) is occurring in many sedimentary basins around the world including Australia, where commercial production of CSG has started in the Surat and Bowen basins. CSG development often involves extraction of large volumes of water that results in depressurising aquifers that overlie and/or underlie the coal seams thus perturbing their flow regimes. This can potentially impact regional aquifer systems that are used for many purposes such as irrigation, and stock and domestic water. In this study, we adopt a probabilistic approach to quantify the depressurisation of the Gunnedah coal seams and how this impacts fluxes to, and from the overlying Great Artesian Basin (GAB) Pilliga Sandstone aquifer. The proposed method is suitable when effects of a new resource development activity on the regional groundwater balance needs to be assessed and account for large scale uncertainties in the groundwater flow system and proposed activity. The results indicated that the extraction of water and gas from the coal seam could potentially induce additional fluxes from the Pilliga Sandstone to the deeper formations due to lowering pressure heads in the coal seams. The median value of the rise in the maximum flux from the Pilliga Sandstone to the deeper formations is estimated to be 85ML/year, which is considered insignificant as it forms only about 0.29% of the Long Term Annual Average Extraction Limit of 30GL/year from the groundwater management area. The probabilistic simulation of the water balance components indicates only small changes being induced by CSG development that influence interactions of the Pilliga Sandstone with the overlying and underlying formations and with the surface water courses. The current analyses that quantified the potential maximum impacts of resource developments and how they influences the regional water balance, would greatly underpin future management decisions. Copyright © 2018 Elsevier B.V. All rights

Medium-term perspectives of the natural gas industry

International Nuclear Information System (INIS)

Chabrelie, M.F.

2007-01-01

During the 1990's, natural gas was the energy source with the fastest rate of growth in the world energy balance. Nevertheless, recent evolutions of the energy context, in particular in terms of prices, have had a rather strong impact on the progress of the different energy sources penalizing gas a little. Beyond this competition between energies, which may increase, the medium-term perspectives of natural gas development is in keeping with an environment full of uncertainties. This article presents: the world supply and demand prospects for 2010-2015 (impact of high gas prices on other energy sources, occurrence of production constraints, political decisions of producing countries and world gas industry balance), trends on main markets (North America, Europe, Asia-Oceania), and international trade. (J.S.)

Determinants of sport-specific postural control strategy and balance performance of amateur rugby players.

Science.gov (United States)

Chow, Gary C C; Fong, Shirley S M; Chung, Joanne W Y; Chung, Louisa M Y; Ma, Ada W W; Macfarlane, Duncan J

2016-11-01

Postural control strategy and balance performance of rugby players are important yet under-examined issues. This study aimed to examine the differences in balance strategy and balance performance between amateur rugby players and non-players, and to explore training- and injury-related factors that may affect rugby players' balance outcomes. Cross-sectional and exploratory study. Forty-five amateur rugby players and 41 healthy active individuals participated in the study. Balance performance and balance strategies were assessed using the sensory organization test (SOT) of the Smart Equitest computerized dynamic posturography machine. Rugby training history and injury history were solicited from the participants. The SOT strategy scores were 1.99-54.90% lower in the rugby group than in the control group (prugby group than in the control group (prugby training (in years) was independently associated with the SOT condition 6 strategy score, explaining 15.7% of its variance (p=0.006). There was no association between SOT condition 6 strategy/equilibrium scores and injury history among the rugby players (p>0.05). Amateur rugby players demonstrated inferior balance strategy and balance performance compared to their non-training counterparts. Their suboptimal balance strategy was associated with insufficient training experience but not with history of injury. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Evaluation and application of site-specific data to revise the first-order decay model for estimating landfill gas generation and emissions at Danish landfills

DEFF Research Database (Denmark)

Mou, Zishen; Scheutz, Charlotte; Kjeldsen, Peter

2015-01-01

Methane (CH4) generated from low-organic waste degradation at four Danish landfills was estimated by three first-order decay (FOD) landfill gas (LFG) generation models (LandGEM, IPCC, and Afvalzorg). Actual waste data from Danish landfills were applied to fit model (IPCC and Afvalzorg) required...... categories. In general, the single-phase model, LandGEM, significantly overestimated CH4 generation, because it applied too high default values for key parameters to handle low-organic waste scenarios. The key parameters were biochemical CH4 potential (BMP) and CH4 generation rate constant (k...... landfills (from the start of disposal until 2020 and until 2100). Through a CH4 mass balance approach, fugitive CH4 emissions from whole sites and a specific cell for shredder waste were aggregated based on the revised Afvalzorg model outcomes. Aggregated results were in good agreement with field...

cGAS-mediated control of blood-stage malaria promotes Plasmodium-specific germinal center responses.

Science.gov (United States)

Hahn, William O; Butler, Noah S; Lindner, Scott E; Akilesh, Holly M; Sather, D Noah; Kappe, Stefan Hi; Hamerman, Jessica A; Gale, Michael; Liles, W Conrad; Pepper, Marion

2018-01-25

Sensing of pathogens by host pattern recognition receptors is essential for activating the immune response during infection. We used a nonlethal murine model of malaria (Plasmodium yoelii 17XNL) to assess the contribution of the pattern recognition receptor cyclic GMP-AMP synthase (cGAS) to the development of humoral immunity. Despite previous reports suggesting a critical, intrinsic role for cGAS in early B cell responses, cGAS-deficient (cGAS-/-) mice had no defect in the early expansion or differentiation of Plasmodium-specific B cells. As the infection proceeded, however, cGAS-/- mice exhibited higher parasite burdens and aberrant germinal center and memory B cell formation when compared with littermate controls. Antimalarial drugs were used to further demonstrate that the disrupted humoral response was not B cell intrinsic but instead was a secondary effect of a loss of parasite control. These findings therefore demonstrate that cGAS-mediated innate-sensing contributes to parasite control but is not intrinsically required for the development of humoral immunity. Our findings highlight the need to consider the indirect effects of pathogen burden in investigations examining how the innate immune system affects the adaptive immune response.

EFFICACY OF A SPORTS SPECIFIC BALANCE TRAINING PROGRAMME ON THE INCIDENCE OF ANKLE SPRAINS IN BASKETBALL

Directory of Open Access Journals (Sweden)

Elke Cumps

2007-06-01

Full Text Available The purpose of the study was to determine the efficacy of a 22- week prescribed sports specific balance training programme on the incidence of lateral ankle sprains in basketball players. A controlled clinical trial was set up. In total 54 subjects of six teams participated and were assigned to either an intervention (IG or a control group (CG. The IG performed a prescribed balance training programme on top of their normal training routine, using balance semi-globes. The programme consisted of 4 basketball skills each session and its difficulty was progressively thought-out. The intervention lasted 22 weeks and was performed 3 times a week for 5 to 10 minutes. Efficacy of the intervention on the incidence of lateral ankle sprains was determined by calculating Relative Risks (RR, including their 95% Confidence Intervals or CI and incidence rates expressed per 1000h. RR (95% CI showed a significantly lower incidence of lateral ankle sprains in the IG compared to the CG for the total sample (RR= 0.30 [95% CI: 0.11-0.84] and in men (RR= 0.29 [95% CI: 0.09-0.93]. The difference in RR was not confirmed when examining the incidence rates and their 95%CI's, which overlapped. The risk for new or recurrent ankle sprains was slightly lower in the IG (new: RR= 0.76 [95% CI: 0.17-3.40]; re-injury: RR= 0.21 [95% CI: 0.03-1.44]. Based on these pilot results, the use of balance training is recommended as a routine during basketball activities for the prevention of ankle sprains

Natural gas power generation: interruptible gas distribution network regulation; Geracao termoeletrica a gas natural: regulacao do segmento interruptivel de distribuicao de gas canalizado

Energy Technology Data Exchange (ETDEWEB)

Paula, Claudio Paiva de; Kann, Zevi [Agencia Reguladora de Saneamento e Energia do Estado de Sao Paulo (ARSESP), SP (Brazil)

2008-07-01

The paper relates studies regarding the natural gas distribution network interruptible branch. This new service can be appropriate for thermal power generation on flexible dispatch mode, as 'take or pay' contracts surplus jobs. The paper indicates no regulatory restraints in an interruptible network implantation. The final conclusion is that interruptible contracts can be an improvement on the distribution business and certainly can accommodate a suitable demand and supply volumes in the long-term gas market balance. (author)

The effect of single-task and dual-task balance exercise programs on balance performance in adults with osteoporosis: a randomized controlled preliminary trial.

Science.gov (United States)

Konak, H E; Kibar, S; Ergin, E S

2016-11-01

Osteoporosis is a serious disease characterized by muscle weakness in the lower extremities, shortened length of trunk, and increased dorsal kyphosis leading to poor balance performance. Although balance impairment increases in adults with osteoporosis, falls and fall-related injuries have been shown to occur mainly during the dual-task performance. Several studies have shown that dual-task performance was improved with specific repetitive dual-task exercises. The aims of this study were to compare the effect of single- and dual-task balance exercise programs on static balance, dynamic balance, and activity-specific balance confidence in adults with osteoporosis and to assess the effectiveness of dual-task balance training on gait speed under dual-task conditions. Older adults (N = 42) (age range, 45-88 years) with osteoporosis were randomly assigned into two groups. Single-task balance training group was given single-task balance exercises for 4 weeks, whereas dual-task balance training group received dual-task balance exercises. Participants received 45-min individualized training session, three times a week. Static balance was evaluated by one-leg stance (OLS) and a kinesthetic ability trainer (KAT) device. Dynamic balance was measured by the Berg Balance Scale (BBS), Time Up and Go (TUG) test, and gait speed. Self-confidence was assessed with the Activities-specific Balance Confidence (ABC-6) scale. Assessments were performed at baseline and after the 4-week program. At the end of the treatment periods, KAT score, BBS score, time in OLS and TUG, gait speeds under single- and dual-task conditions, and ABC-6 scale scores improved significantly in all patients (p gait speeds under single- and dual-task conditions showed significantly greater improvement in the dual-task balance training group than in the single-task balance training group (p gait speeds showed greater improvement following the application of a specific type of dual-task exercise programs

A differential evolution algorithm for tooth profile optimization with respect to balancing specific sliding coefficients of involute cylindrical spur and helical gears

Directory of Open Access Journals (Sweden)

Hammoudi Abderazek

2015-09-01

Full Text Available Profile shift has an immense effect on the sliding, load capacity, and stability of involute cylindrical gears. Available standards such as ISO/DIS 6336 and BS 436 DIN/3990 currently give the recommendation for the selection of profile shift coefficients. It is, however, very approximate and usually given in the form of implicit graphs or charts. In this article, the optimal selection values of profile shift coefficients for cylindrical involute spur and helical gears are described, using a differential evolution algorithm. The optimization procedure is developed specifically for exact balancing specific sliding coefficients at extremes of contact path and account for gear design constraints. The obtained results are compared with those of standards and research of other authors. They demonstrate the effectiveness and robustness of the applied method. A substantial improvement in balancing specific sliding coefficients is found in this work.

Absence of a market in the Dutch balancing mechanism: European rules versus specific investments

NARCIS (Netherlands)

Niesten, E.M.M.I.; Jolink, A.

2013-01-01

The European directives for the electricity industry prescribe the creation of a market for balancing electricity supply and demand. In this paper, we demonstrate that a market for balancing has not emerged in the Dutch electricity industry, and that, instead, the balancing transactions are

40 CFR 1065.290 - PM gravimetric balance.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 32 2010-07-01 2010-07-01 false PM gravimetric balance. 1065.290... balance. (a) Application. Use a balance to weigh net PM on a sample medium for laboratory testing. (b) Component requirements. We recommend that you use a balance that meets the specifications in Table 1 of...

High methane emissions dominate annual greenhouse gas balances 30 years after bog rewetting

Science.gov (United States)

Vanselow-Algan, M.; Schmidt, S. R.; Greven, M.; Fiencke, C.; Kutzbach, L.; Pfeiffer, E.-M.

2015-02-01

Natural peatlands are important carbon sinks and sources of methane (CH4). In contrast, drained peatlands turn from a carbon sink to a carbon source and potentially emit nitrous oxide (N2O). Rewetting of peatlands thus implies climate change mitigation. However, data about the time span that is needed for the re-establishment of the carbon sink function by restoration is scarce. We therefore investigated the annual greenhouse gas (GHG) balances of three differently vegetated bog sites 30 years after rewetting. All three vegetation communities turned out to be sources of carbon dioxide (CO2) ranging between 0.6 ± 1.43 t CO2 ha-2 yr-1 (Sphagnum-dominated vegetation) and 3.09 ± 3.86 t CO2 ha-2 yr-1 (vegetation dominated by heath). While accounting for the different global warming potential (GWP) of the three greenhouse gases, the annual GHG balance was calculated. Emissions ranged between 25 and 53 t CO2-eq ha-1 yr-1 and were dominated by large emissions of CH4 (22 up to 51 t CO2-eq ha-1 yr-1), while highest rates were found at purple moor grass (Molinia caerulea) stands. These are to our knowledge the highest CH4 emissions so far reported for bog ecosystems in temperate Europe. As the restored area was subject to large fluctuations in water table, we conclude that the high CH4 emission rates were caused by a combination of both the temporal inundation of the easily decomposable plant litter of this grass species and the plant-mediated transport through its tissues. In addition, as a result of the land use history, the mixed soil material can serve as an explanation. With regards to the long time span passed since rewetting, we note that the initial increase in CH4 emissions due to rewetting as described in the literature is not limited to a short-term period.

High methane emissions dominated annual greenhouse gas balances 30 years after bog rewetting

Science.gov (United States)

Vanselow-Algan, M.; Schmidt, S. R.; Greven, M.; Fiencke, C.; Kutzbach, L.; Pfeiffer, E.-M.

2015-07-01

Natural peatlands are important carbon sinks and sources of methane (CH4). In contrast, drained peatlands turn from a carbon sink to a carbon source and potentially emit nitrous oxide (N2O). Rewetting of peatlands thus potentially implies climate change mitigation. However, data about the time span that is needed for the re-establishment of the carbon sink function by restoration are scarce. We therefore investigated the annual greenhouse gas (GHG) balances of three differently vegetated sites of a bog ecosystem 30 years after rewetting. All three vegetation communities turned out to be sources of carbon dioxide (CO2) ranging between 0.6 ± 1.43 t CO2 ha-2 yr-1 (Sphagnum-dominated vegetation) and 3.09 ± 3.86 t CO2 ha-2 yr-1 (vegetation dominated by heath). While accounting for the different global warming potential (GWP) of CO2, CH4 and N2O, the annual GHG balance was calculated. Emissions ranged between 25 and 53 t CO2-eq ha-1 yr-1 and were dominated by large emissions of CH4 (22-51 t CO2-eq ha-1 yr-1), with highest rates found at purple moor grass (Molinia caerulea) stands. These are to our knowledge the highest CH4 emissions so far reported for bog ecosystems in temperate Europe. As the restored area was subject to large fluctuations in the water table, we assume that the high CH4 emission rates were caused by a combination of both the temporal inundation of the easily decomposable plant litter of purple moor grass and the plant-mediated transport through its tissues. In addition, as a result of the land use history, mixed soil material due to peat extraction and refilling can serve as an explanation. With regards to the long time span passed since rewetting, we note that the initial increase in CH4 emissions due to rewetting as described in the literature is not inevitably limited to a short-term period.

Modelling emissions from natural gas flaring

Directory of Open Access Journals (Sweden)

G. Ezaina Umukoro

2017-04-01

Full Text Available The world today recognizes the significance of environmental sustainability to the development of nations. Hence, the role oil and gas industry plays in environmental degrading activities such as gas flaring is of global concern. This study presents material balance equations and predicts results for non-hydrocarbon emissions such as CO2, CO, NO, NO2, and SO2 etc. from flaring (combustion of 12 natural gas samples representing composition of natural gas of global origin. Gaseous emission estimates and pattern were modelled by coding material balance equations for six reaction types and combustion conditions with a computer program. On the average, anticipated gaseous emissions from flaring natural gas with an average annual global flaring rate 126 bcm per year (between 2000 and 2011 in million metric tonnes (mmt are 560 mmt, 48 mmt, 91 mmt, 93 mmt and 50 mmt for CO2, CO, NO, NO2 and SO2 respectively. This model predicted gaseous emissions based on the possible individual combustion types and conditions anticipated in gas flaring operation. It will assist in the effort by environmental agencies and all concerned to track and measure the extent of environmental pollution caused by gas flaring operations in the oil and gas industry.

The short version of the Activities-specific Balance Confidence (ABC) scale: its validity, reliability, and relationship to balance impairment and falls in older adults.

Science.gov (United States)

Schepens, Stacey; Goldberg, Allon; Wallace, Melissa

2010-01-01

A shortened version of the ABC 16-item scale (ABC-16), the ABC-6, has been proposed as an alternative balance confidence measure. We investigated whether the ABC-6 is a valid and reliable measure of balance confidence and examined its relationship to balance impairment and falls in older adults. Thirty-five community-dwelling older adults completed the ABC-16, including the 6 questions of the ABC-6. They also completed the following clinical balance tests: unipedal stance time (UST), functional reach (FR), Timed Up and Go (TUG), and maximum step length (MSL). Participants reported 12-month falls history. Balance confidence on the ABC-6 was significantly lower than on the ABC-16, however scores were highly correlated. Fallers reported lower balance confidence than non-fallers as measured by the ABC-6 scale, but confidence did not differ between the groups with the ABC-16. The ABC-6 significantly correlated with all balance tests assessed and number of falls. The ABC-16 significantly correlated with all balance tests assessed, but not with number of falls. Test-retest reliability for the ABC-16 and ABC-6 was good to excellent. The ABC-6 is a valid and reliable measure of balance confidence in community-dwelling older adults, and shows stronger relationships to falls than does the ABC-16. The ABC-6 may be a more useful balance confidence assessment tool than the ABC-16. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Nesting behaviour influences species-specific gas exchange across avian eggshells.

Science.gov (United States)

Portugal, Steven J; Maurer, Golo; Thomas, Gavin H; Hauber, Mark E; Grim, Tomáš; Cassey, Phillip

2014-09-15

Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (G(H2O)) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell G(H2O) and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in G(H2O) has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between G(H2O) and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher G(H2O) than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher G(H2O) than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the G(H2O) are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher G(H2O) to overcome this constraint and still

Double-yoke balanced compressor

International Nuclear Information System (INIS)

Durenec, P.

1981-01-01

A double-yoke balanced compressor for a cryogenic cooler that has only linear motion imparted to balanced piston and cylinder masses. A piston yoke is driven in the linear stroke direction by a piston axially offset crankshaft cam and a cylinder yoke is driven linearly by a cylinder axially offset crankshaft cam that is exactly offset 180 0 from the other cam. A large circular bushing in the compressor housing covers the entire outer cylinder head during linear operation to prevent blow by and to guide the cylinder linearly. The lower portion of the piston and cylinder connecting rods fit into linear guides that are further comprised of low molecular weight gas filled cavities to provide additional air bearing smoothness to the linear motion of the piston and cylinder

Prognostication : impact on Arctic gas

International Nuclear Information System (INIS)

Duncan, J.

2003-01-01

This PowerPoint presentation featured issues facing the current gas market with reference to the possibility of a supply shortage. The lack of credit-worthy counterparties increases volatility just as dwindling liquidity raises risks. It is expected that, for the most part, Alberta will continue to supply Canadian markets. The author indicated that the Alaska and Mackenzie pipelines need to be constructed. A series of graphs were presented to better illustrate the Mexican exports, gas balance sheet, rig count versus production, etc. Forecasting requires a balance between perception and reality. Demand will depend on weather, and gas prices must go higher. Some of the factors that will impact the market are: war with Iraq, oil prices, North American terrorism, and a sluggish economy. Both the short and long term outlooks are bullish, when it comes to oil prices. The alternative supply sources are: liquefied natural gas (LNG), coalbed methane (CBM), and frontier sources. Each alternative source was examined in detail. One section of the presentation was devoted to master limited partnerships. Risk was discussed, as was technical analysis of forecasting. tabs., figs

A steady-state stomatal model of balanced leaf gas exchange, hydraulics and maximal source-sink flux.

Science.gov (United States)

Hölttä, Teemu; Lintunen, Anna; Chan, Tommy; Mäkelä, Annikki; Nikinmaa, Eero

2017-07-01

Trees must simultaneously balance their CO2 uptake rate via stomata, photosynthesis, the transport rate of sugars and rate of sugar utilization in sinks while maintaining a favourable water and carbon balance. We demonstrate using a numerical model that it is possible to understand stomatal functioning from the viewpoint of maximizing the simultaneous photosynthetic production, phloem transport and sink sugar utilization rate under the limitation that the transpiration-driven hydrostatic pressure gradient sets for those processes. A key feature in our model is that non-stomatal limitations to photosynthesis increase with decreasing leaf water potential and/or increasing leaf sugar concentration and are thus coupled to stomatal conductance. Maximizing the photosynthetic production rate using a numerical steady-state model leads to stomatal behaviour that is able to reproduce the well-known trends of stomatal behaviour in response to, e.g., light, vapour concentration difference, ambient CO2 concentration, soil water status, sink strength and xylem and phloem hydraulic conductance. We show that our results for stomatal behaviour are very similar to the solutions given by the earlier models of stomatal conductance derived solely from gas exchange considerations. Our modelling results also demonstrate how the 'marginal cost of water' in the unified stomatal conductance model and the optimal stomatal model could be related to plant structural and physiological traits, most importantly, the soil-to-leaf hydraulic conductance and soil moisture. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Position-specific 13C distributions within propane from experiments and natural gas samples

Science.gov (United States)

Piasecki, Alison; Sessions, Alex L.; Lawson, Michael; Ferreira, A.A.; Santos Neto, E. V.; Ellis, Geoffrey S.; Lewan, Michael; Eilers, J.M.

2018-01-01

Site-specific carbon isotope measurements of organic compounds potentially recover information that is lost in a conventional, ‘bulk’ isotopic analysis. Such measurements are useful because isotopically fractionating processes may have distinct effects at different molecular sites, and thermodynamically equilibrated populations of molecules tend to concentrate heavy isotopes in one molecular site versus another. Most recent studies of site-specific 13C in organics use specialized Nuclear Magnetic Resonance (NMR) techniques or complex chemical degradations prior to mass spectrometric measurements. Herein we present the first application of a new mass spectrometric technique that reconstructs the site-specific carbon isotope composition of propane based on measurements of the 13C/12C ratios of two or more fragment ions that sample different proportions of the terminal and central carbon sites. We apply this method to propane from laboratory experiments and natural gas samples to explore the relationships between site-specific carbon isotope composition, full-molecular δ13C, thermal maturity, and variation in organic matter precursors. Our goal is to advance the understanding of the sources and histories of short-chain alkanes within geologic systems. Our findings suggest that propane varies in its site-specific carbon isotope structure, which is correlated with increasing thermal maturity, first increasing in terminal position δ13C and then increasing in both center and terminal position δ13C. This pattern is observed in both experimental and natural samples, and is plausibly explained by a combination of site-specific, temperature-dependent isotope effects associated with conversion of different precursor molecules (kerogen, bitumen, and/or oil) to propane, differences in site-specific isotopic contents of those precursors, and possibly distillation of reactive components of those precursors with increasing maturity. We hypothesize that the largest changes in

Position-specific 13C distributions within propane from experiments and natural gas samples

Science.gov (United States)

Piasecki, Alison; Sessions, Alex; Lawson, Michael; Ferreira, A. A.; Santos Neto, E. V.; Ellis, Geoffrey S.; Lewan, Michael D.; Eiler, John M.

2018-01-01

Site-specific carbon isotope measurements of organic compounds potentially recover information that is lost in a conventional, 'bulk' isotopic analysis. Such measurements are useful because isotopically fractionating processes may have distinct effects at different molecular sites, and thermodynamically equilibrated populations of molecules tend to concentrate heavy isotopes in one molecular site versus another. Most recent studies of site-specific 13C in organics use specialized Nuclear Magnetic Resonance (NMR) techniques or complex chemical degradations prior to mass spectrometric measurements. Herein we present the first application of a new mass spectrometric technique that reconstructs the site-specific carbon isotope composition of propane based on measurements of the 13C/12C ratios of two or more fragment ions that sample different proportions of the terminal and central carbon sites. We apply this method to propane from laboratory experiments and natural gas samples to explore the relationships between site-specific carbon isotope composition, full-molecular δ13C, thermal maturity, and variation in organic matter precursors. Our goal is to advance the understanding of the sources and histories of short-chain alkanes within geologic systems. Our findings suggest that propane varies in its site-specific carbon isotope structure, which is correlated with increasing thermal maturity, first increasing in terminal position δ13C and then increasing in both center and terminal position δ13C. This pattern is observed in both experimental and natural samples, and is plausibly explained by a combination of site-specific, temperature-dependent isotope effects associated with conversion of different precursor molecules (kerogen, bitumen, and/or oil) to propane, differences in site-specific isotopic contents of those precursors, and possibly distillation of reactive components of those precursors with increasing maturity. We hypothesize that the largest changes in

Paludiculture as a chance for peatland and climate: the greenhouse gas balance of biomass production on two rewetted peatlands does not differ from the natural state

Science.gov (United States)

Günther, Anke; Huth, Vytas; Jurasinski, Gerald; Albrecht, Kerstin; Glatzel, Stephan

2015-04-01

In Europe, rising prices for farm land make it increasingly difficult for government administrations to compete with external investors during the acquisition of land for wetland conservation. Thus, adding economic value to these, otherwise "lost", areas by combining extensive land use with nature conservation efforts could increase the amount of ground available for wetland restoration. Against this background, the concept of paludiculture aims to provide biomass for multiple purposes from peatlands with water tables high enough to conserve the peat body. However, as plants have been shown to contribute to greenhouse gas exchange in peatlands, manipulating the vegetation (by harvesting, sowing etc.) might alter the effect of the restored peatlands on climate. Here, we present greenhouse gas data from two experimental paludiculture systems on formerly drained intensive grasslands in northern Germany. In a fen that has been rewetted more than 15 years ago three species of reed plants were harvested to simulate biomass production for bioenergy and as construction material. And in a peat bog that has been converted from drained grassland to a field with a controlled water table around ground surface Sphagnum mosses were cultivated to provide an alternative growing substrate for horticulture. In both systems, we determined carbon dioxide, methane, and nitrous oxide exchange using closed chambers over two years. Additionally, water and peat chemistry and environmental parameters as recorded by a weather station were analyzed. Both restored peatlands show greenhouse gas balances comparable to those of natural ecosystems. Nitrous oxide was not emitted in either system. Fluctuations of the emissions reflect changes in weather conditions across the study years. In the fen, relative emission patterns between plant species were not constant over time. We did not find a negative short-term effect of biomass harvest or Sphagnum cultivation on net greenhouse gas balances

Analysis of an innovative process for landfill gas quality improvement

International Nuclear Information System (INIS)

Lombardi, L.; Carnevale, E.A.

2016-01-01

Low methane content landfill gas is not suitable for feeding engines and is generally flared. This type of landfill gas may be enriched by removing the inert carbon dioxide. An innovative process, based on the carbon dioxide captured by means of accelerated carbonation of bottom ash was proposed and studied for the above purpose. The process was investigated at a laboratory scale, simulating different landfill gas compositions. The enrichment process is able to decrease the carbon dioxide concentration from 70 to 80% in volume to 60% in volume, requiring about 36 kg of bottom ash per Nm"3 of landfill gas. Using this result it was estimated that an industrial scale plant, processing 100–1000 Nm"3/h of low methane content landfill gas requires about 28,760–2,87,600 t of bottom ash for a one year operation. The specific cost of the studied enrichment process was evaluated as well and ranges from 0.052 to 0.241 Euro per Nm"3 of entering landfill gas. The energy balance showed that about 4–6% of the energy entered with the landfill gas is required for carrying out the enrichment, while the use of the enriched landfill gas in the engine producing electricity allows for negative carbon dioxide emission. - Highlights: • The process uses a waste stream as material to capture CO_2. • The process uses a simple gas/solid fixed bed contact reactor at ambient conditions. • The process captures the CO_2 to enrich low-CH4 landfill gas. • The specific cost ranges from 0.052 to 0.241 Euro per Nm"3 of entering landfill gas. • The process consumes about 4–6% of the entering energy and acts as CO_2 sink.

Am/Cm Vitrification Process: Vitrification Material Balance Calculations

International Nuclear Information System (INIS)

Smith, F.G.

2000-01-01

This report documents material balance calculations for the Americium/Curium vitrification process and describes the basis used to make the calculations. The material balance calculations reported here start with the solution produced by the Am/Cm pretreatment process as described in ``Material Balance Calculations for Am/Cm Pretreatment Process (U)'', SRT-AMC-99-0178 [1]. Following pretreatment, small batches of the product will be further treated with an additional oxalic acid precipitation and washing. The precipitate from each batch will then be charged to the Am/Cm melter with glass cullet and vitrified to produce the final product. The material balance calculations in this report are designed to provide projected compositions of the melter glass and off-gas streams. Except for decanted supernate collected from precipitation and precipitate washing, the flowsheet neglects side streams such as acid washes of empty tanks that would go directly to waste. Complete listings of the results of the material balance calculations are provided in the Appendices to this report

BALANCER: A Computer Program for Balancing Chemical Equations.

Science.gov (United States)

Jones, R. David; Schwab, A. Paul

1989-01-01

Describes the theory and operation of a computer program which was written to balance chemical equations. Software consists of a compiled file of 46K for use under MS-DOS 2.0 or later on IBM PC or compatible computers. Additional specifications of courseware and availability information are included. (Author/RT)

Mitigation of indoor radon using balanced mechanical ventilation

International Nuclear Information System (INIS)

Wellford, B.W.

1986-01-01

Previous research has shown that, for a given source strength, the concentration of Rn 222 in the home is inversely proportional to the ventilation rate. Further reductions in the concentration of the decay products of radon can be achieved due to the decrease in residence time of the parent gas as well as increased plate-out of the progeny. Natural and mechanical ventilation can affect the distribution of pressure across the building envelope potentially increasing the flow of radon bearing soil gas into the home gas into the home and/or promoting mixing of areas of higher and lower concentration. Balanced heat recovery ventilation systems were installed in ten homes in the Boyertown, Pennsylvania area. Ventilation was restricted initially to the basement area. Five installations were later modified to introduce supply air to upstairs living spaces while continuing to exhaust from the basement. An independent contractor measured Rn 222 concentrations and decay product activity in the basement and first floor living area before and after installation or modification of the heat recovery ventilation system. Additional experiments to evaluate the effect of house tightening techniques and positive pressurization of the basement were conducted. With balanced ventilation of the basement only, the mean reduction in Working Level was 92.8% with a high of 98% and a low of 76%. Mean reduction of radon gas concentration was 79.1%. When modified to supply air upstairs, mean reduction in Working Level in the living area was 90%. House tightening measures to reduce stack effect were observed to reduce radon concentration. Results indicate that balanced ventilation is an effective strategy for radon mitigation and can be expected to achieve recommended levels in a majority of homes. 9 references, 2 figures, 2 tables

The short version of the Activities-specific Balance Confidence (ABC) scale: Its validity, reliability, and relationship to balance impairment and falls in older adults

OpenAIRE

Schepens, Stacey; Goldberg, Allon; Wallace, Melissa

2009-01-01

A shortened version of the ABC 16-item scale (ABC-16), the ABC-6, has been proposed as an alternative balance confidence measure. We investigated whether the ABC-6 is a valid and reliable measure of balance confidence and examined its relationship to balance impairment and falls in older adults. Thirty-five community-dwelling older adults completed the ABC-16, including the six questions of the ABC-6. They also completed the following clinical balance tests: unipedal stance time (UST), functi...

Greenhouse gas and energy analysis of substitute natural gas from biomass for space heat

International Nuclear Information System (INIS)

Pucker, Johanna; Zwart, Robin; Jungmeier, Gerfried

2012-01-01

In this paper, the greenhouse gas and energy balances of the production and use for space heating of substitute natural gas from biomass (bio-SNG) for space heat are analysed. These balances are compared to the use of natural gas and solid biomass as wood chips to provide the same service. The reduction of the greenhouse gas emissions (CO 2 -eq.) – carbon dioxide, methane and nitrous oxide – and of the fossil primary energy use is investigated in a life cycle assessment (LCA). This assessment was performed for nine systems for bio-SNG; three types of gasification technologies (O 2 -blown entrained flow, O 2 -blown circulating fluidised bed and air–steam indirect gasification) with three different types of feedstock (forest residues, miscanthus and short rotation forestry). The greenhouse gas analysis shows that forest residues using the air–steam indirect gasification technology result in the lowest greenhouse gas emissions (in CO 2 -eq. 32 kg MWh −1 of heat output). This combination results in 80% reduction of greenhouse gas emissions when compared to natural gas and a 29% reduction of greenhouse gases if the forest residues were converted to wood chips and combusted. The gasification technologies O 2 -blown entrained flow and O 2 -blown circulating fluidised bed gasification have higher greenhouse gas emissions that range between in CO 2 -eq. 41 to 75 kg MWh −1 of heat output depending on the feedstock. When comparing feedstocks in the bio-SNG systems, miscanthus had the highest greenhouse gas emissions bio-SNG systems producing in CO 2 -eq. 57–75 kg MWh −1 of heat output. Energy analysis shows that the total primary energy use is higher for bio-SNG systems (1.59–2.13 MWh MWh −1 of heat output) than for the reference systems (in 1.37–1.51 MWh MWh −1 of heat output). However, with bio-SNG the fossil primary energy consumption is reduced compared to natural gas. For example, fossil primary energy use is reduced by 92% when air�

High-BTU gas production from tar-bearing hot coke oven gas over iron catalyst

Energy Technology Data Exchange (ETDEWEB)

L.Y. Li; K. Morishita; T. Takarada [Gunma University, Gunma (Japan). Department of Biological and Chemical Engineering

2005-07-01

To utilize the tar-bearing hot coke oven gas (the by-product of coke making process) more effectively, a process was developed by converting the hot coke oven gas into a methane rich high-BTU gas over iron-bearing catalysts. The catalytic behaviour of Indonesian limonite ore was mainly discussed. For a reference, a conventional nickel catalyst (Ni/Al{sub 2}O{sub 3}) was employed. Laboratory scale tests were carried out in a two-stage fixed-bed reactor at ambient pressure. A bituminous coal sample was heated at first stage, the volatiles was carried by feed gas and decomposed at second stage. The limonite promoted hydropyrolysis of coal volatiles similar to Ni/Al{sub 2}O{sub 3} catalyst. High yields of total product gas and methane were obtained at 50 vol.% hydrogen atmosphere with a feed gas of 60 ml min{sup -1} hydrogen and 60 ml min{sup -1} nitrogen. After experiments, hydrocarbons heavier than ethane were not observed. Also that, carbon balance was more than 99.8% in coal char, product gases and carbon deposits. It was considered that coal volatiles converted into light gases and carbon almost completely in catalyst bed. Yields of product gas and methane depended upon catalytic temperature. At 923 K, the maximum yield of product gas was achieved at 74.3% for limonite catalyst on carbon balance with methane 83.2 vol.% of the carbonaceous gas products. Comparing with limonite, Fe/Al{sub 2}O{sub 3} and BOF dust samples showed low activities on coal volatiles catalytic decomposition. 21 refs., 5 figs., 3 tabs.

Non-isothermal compositional gas flow during carbon dioxide storage and enhanced gas recovery

DEFF Research Database (Denmark)

Singh, Ashok; Böettcher, N.; Wang, W.

2011-01-01

In this work we present the conceptual modeling and the numerical scheme for carbon dioxide storage into nearly depleted gas reservoirs for enhanced gas recovery reasons. For this we develop non-isothermal compositional gas flow model. We used a combined monolithic / staggered coupling scheme...... to solve mass balance equation for the gaseous mixture with heat and fractional mass transport equations. Temperature change resulting from fluid expansion and viscous heat dissipation is included in heat transport in addition to advection and conduction. We have used a modified version of the Peng...

The variation of particle gas-borne concentration with time in a gas cooled reactor

International Nuclear Information System (INIS)

Reed, J.; Hall, D.; Reeks, M.W.

1985-01-01

If volatile fission products are released from fuel during a reactor fault, a significant fraction could become attached to small particles also present in the coolant. In such circumstances the retention of those particles by the reactor circuit will limit the level of gas-borne particle concentration and hence be important in reducing the potential release of fission product activity to the atmosphere. Clearly the retention of particles will be influenced by both the deposition and resuspension of particles from surfaces exposed to the coolant flow. In this paper we consider deposition and resuspension but pay particular attention to the role of resuspension, which in the past has been given little consideration. A recently developed model for the resuspension of small particles by a turbulent flow is outlined. Traditionally, resuspension has been interpreted as a force balance between the aerodynamic removal forces and the surface adhesive forces. In contrast, this new approach embodies an energy balance criterion for particle resuspension. Furthermore, the stochastic nature of this new model has shown that resuspension can be sub-divided into two regimes: (i) initial resuspension (resuspension occurring in times less than a second) which reduces the net deposition of particles to a surface; and (ii) longer term resuspension (resuspension after 1 second) which determines the asymptotic decay of particle gas-borne concentration. It is seen that the asymptotic decay varies almost inversely as the decay time. Force balance models are unsuccessful in accounting for the experimentally observed longer term resuspension. We show that a Volterra integro-differential equation best describes the variation of particle gas-borne concentration with time in a recirculating gas flow such as a gas cooled reactor. It is seen that the longer term resuspension has a major influence in the final decay of particle concentration. (author)

The variation of particle gas-borne concentration with time in a gas cooled reactor

Energy Technology Data Exchange (ETDEWEB)

Reed, J; Hall, D; Reeks, M W [Central Electricity Generating Board, Berkeley Nuclear Laboratories (United Kingdom)

1985-07-01

If volatile fission products are released from fuel during a reactor fault, a significant fraction could become attached to small particles also present in the coolant. In such circumstances the retention of those particles by the reactor circuit will limit the level of gas-borne particle concentration and hence be important in reducing the potential release of fission product activity to the atmosphere. Clearly the retention of particles will be influenced by both the deposition and resuspension of particles from surfaces exposed to the coolant flow. In this paper we consider deposition and resuspension but pay particular attention to the role of resuspension, which in the past has been given little consideration. A recently developed model for the resuspension of small particles by a turbulent flow is outlined. Traditionally, resuspension has been interpreted as a force balance between the aerodynamic removal forces and the surface adhesive forces. In contrast, this new approach embodies an energy balance criterion for particle resuspension. Furthermore, the stochastic nature of this new model has shown that resuspension can be sub-divided into two regimes: (i) initial resuspension (resuspension occurring in times less than a second) which reduces the net deposition of particles to a surface; and (ii) longer term resuspension (resuspension after 1 second) which determines the asymptotic decay of particle gas-borne concentration. It is seen that the asymptotic decay varies almost inversely as the decay time. Force balance models are unsuccessful in accounting for the experimentally observed longer term resuspension. We show that a Volterra integro-differential equation best describes the variation of particle gas-borne concentration with time in a recirculating gas flow such as a gas cooled reactor. It is seen that the longer term resuspension has a major influence in the final decay of particle concentration. (author)

A new integrated planning model for gas compression and transmission through a complex pipeline network; Um novo modelo de planejamento integrado de compressao e escoamento de gas para uma rede complexa

Energy Technology Data Exchange (ETDEWEB)

Iamashita, Edson K. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Galaxe, Frederico; Arica, Jose [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacases, RJ (Brazil)

2005-07-01

The aim of this paper is to show a new approach to solve integrated gas balance planning problems that defines the best compression and transmission strategy for a system with a large number of platforms or compression units that are interlinked with the delivery points through a complex gas pipeline network. For solving the proposed optimization problem is used a genetic meta-heuristic technique, where the fitness function of the algorithm is the Profit function of the gas balance, being considered the incomes and costs besides the pipeline network constraints, representing the compression system and transmission network near to the real operational condition. Newton Raphson's method is used to solve the nonlinear system that represents the calculation of the pressure drop in the gas pipeline network that can contain various cycles. This model could be used for design and optimization of gas pipeline networks, as well as for the gas balance planning of an existent network looking for the profit maximization. (author)

Canadian natural gas : market review and outlook

International Nuclear Information System (INIS)

2001-01-01

This annual working paper provides summaries of trends within the North American natural gas industry and also reviews Canadian gas exports. It is designed to promote dialogue between industry and the government and to obtain feedback on natural gas issues. The main section of the report consists of graphs, with limited text comments on the side. It provides a structured look at supply and demand for the year 2000 as well as for the near term (2001) and long-term (2010). The sources of information included private consultants, industry associations and federal agencies in Canada and the United States. It was shown that gas demand had grown steadily in North America since 1997, at about 2.5 per cent annually, and then fell 3.4 per cent in 1998 and remained low in 1999, below 1997 demand. This was due mainly to mild winters. In 2000, the demand for natural gas increased again to 5 per cent as a result of a colder winter and increased gas use for power generation. The report also stated that the combination of various factors including low storage balances due to previously low drilling years and high oil prices, were responsible for natural gas price increases in 2000. The tight supply/demand balance was exacerbated by restraints in pipeline capacity. Producers and pipeline groups are now looking seriously at developing the large gas deposits in Alaska and the Mackenzie Delta which were previously considered to be uneconomic. It was noted that in the near term, storage must be rebuilt to normal levels. Storage balances will be a good indicator of the relative strengths of gas production and demand growth. It was forecasted that Canada to U.S. gas exports should continue to increase in 2001 as a large new export pipeline was completed in 2000, but there is considerable uncertainty for the medium to longer-term. refs., tabs., figs

Effects of circular gait training on balance, balance confidence in patients with stroke: a pilot study.

Science.gov (United States)

Park, Shin-Kyu; Kim, Sung-Jin; Yoon, Tak Yong; Lee, Suk-Min

2018-05-01

[Purpose] This study aimed to investigate the effects of circular gait training on balance and balance confidence in patients with stroke. [Subjects and Methods] Fifteen patients with stroke were randomly divided into either the circular gait training (CGT) group (n=8) or the straight gait training (SGT) group (n=7). Both groups had conventional therapy that adhered to the neurodevelopmental treatment (NDT) approach, for 30 min. In addition, the CGT group performed circular gait training, and the SGT group practiced straight gait training for 30 min. Each intervention was applied for 1 h, 5 days a week, for 2 weeks. Berg Balance Scale (BBS), Timed Up and Go (TUG) test, and Activities-specific Balance Confidence (ABC) scale were used to test balance and balance confidence. [Results] After the intervention, both groups showed significant increases in balance and balance confidence. Significant improvements in the balance of the CGT group compared with the SGT group were observed at post-assessment. [Conclusion] This study showed that circular gait training significantly improves balance in patients with stroke.

Alternative energy balances for Bulgaria to mitigate climate change

Science.gov (United States)

Christov, Christo

1996-01-01

Alternative energy balances aimed to mitigate greenhouse gas (GHG) emissions are developed as alternatives to the baseline energy balance. The section of mitigation options is based on the results of the GHG emission inventory for the 1987 1992 period. The energy sector is the main contributor to the total CO2 emissions of Bulgaria. Stationary combustion for heat and electricity production as well as direct end-use combustion amounts to 80% of the total emissions. The parts of the energy network that could have the biggest influence on GHG emission reduction are identified. The potential effects of the following mitigation measures are discussed: rehabilitation of the combustion facilities currently in operation; repowering to natural gas; reduction of losses in thermal and electrical transmission and distribution networks; penetration of new combustion technologies; tariff structure improvement; renewable sources for electricity and heat production; wasteheat utilization; and supply of households with natural gas to substitute for electricity in space heating and cooking. The total available and the achievable potentials are estimated and the implementation barriers are discussed.

Energy balances of OECD countries 1970/1982

International Nuclear Information System (INIS)

Anon.

1984-01-01

The present volume provides standardized energy balance sheets expressed in a common unit of tons of oil equivalent for all OECD Countries. It covers the years 1970 to 1982 year by year and includes many revisions and additions to data previously published. The balances in the present volume are based on data published in OECD Energy Statistics 1971-1981 and OECD Energy Statistics 1981-1982. Tables for each OECD Country include production, import, export, consumption by the different industries, transportation, agriculture, residential sector of the different energies: solid fuels, petroleum, gas, nuclear power and hydroelectricity [fr

Activities-specific balance confidence scale for predicting future falls in Indian older adults

Directory of Open Access Journals (Sweden)

Moiz JA

2017-04-01

Full Text Available Jamal Ali Moiz,1 Vishal Bansal,2 Majumi M Noohu,1 Shailendra Nath Gaur,3 Mohammad Ejaz Hussain,1 Shahnawaz Anwer,4,5 Ahmad Alghadir4 1Centre for Physiotherapy and Rehabilitation Sciences, Jamia Millia Islamia, New Delhi, India; 2Department of Physiology, 3Department of Respiratory Medicine, Vallabhbhai Patel Chest Institute, University of Delhi, Delhi, India; 4Rehabilitation Research Chair, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; 5Department of Musculoskeletal Science, Dr D.Y. Patil College of Physiotherapy, Dr D.Y. Patil Vidyapeeth, Pune, India Background: Activities-specific balance confidence (ABC scale is a subjective measure of confidence in performing various ambulatory activities without falling or experiencing a sense of unsteadiness. Objective: This study aimed to examine the ability of the Hindi version of the ABC scale (ABC-H scale to discriminate between fallers and non-fallers and to examine its predictive validity for prospective falls. Design: This was a prospective cohort study. Materials and methods: A total of 125 community-dwelling older adults (88 were men completed the ABC-H scale. The occurrence of falls over the follow-up period of 12 months was recorded. Discriminative validity was analyzed by comparing the total ABC-H scale scores between the faller and non-faller groups. A receiver operating characteristic curve analysis and a logistic regression analysis were used to examine the predictive accuracy of the ABC-H scale. Results: The mean ABC-H scale score of the faller group was significantly lower than that of the non-faller group (52.6±8.1 vs 73.1±12.2; P<0.001. The optimal cutoff value for distinguishing faller and non-faller adults was ≤58.13. The sensitivity, specificity, area under the curve, and positive and negative likelihood ratios of the cutoff score were 86.3%, 87.3%, 0.91 (P<0.001, 6.84, and 0.16, respectively. The percentage test accuracy and false-positive and

Balance confidence is related to features of balance and gait in individuals with chronic stroke

Science.gov (United States)

Schinkel-Ivy, Alison; Wong, Jennifer S.; Mansfield, Avril

2016-01-01

Reduced balance confidence is associated with impairments in features of balance and gait in individuals with sub-acute stroke. However, an understanding of these relationships in individuals at the chronic stage of stroke recovery is lacking. This study aimed to quantify relationships between balance confidence and specific features of balance and gait in individuals with chronic stroke. Participants completed a balance confidence questionnaire and clinical balance assessment (quiet standing, walking, and reactive stepping) at 6 months post-discharge from inpatient stroke rehabilitation. Regression analyses were performed using balance confidence as a predictor variable and quiet standing, walking, and reactive stepping outcome measures as the dependent variables. Walking velocity was positively correlated with balance confidence, while medio-lateral centre of pressure excursion (quiet standing) and double support time, step width variability, and step time variability (walking) were negatively correlated with balance confidence. This study provides insight into the relationships between balance confidence and balance and gait measures in individuals with chronic stroke, suggesting that individuals with low balance confidence exhibited impaired control of quiet standing as well as walking characteristics associated with cautious gait strategies. Future work should identify the direction of these relationships to inform community-based stroke rehabilitation programs for individuals with chronic stroke, and determine the potential utility of incorporating interventions to improve balance confidence into these programs. PMID:27955809

Isostructural and cage-specific replacement occurring in sII hydrate with external CO2/N2 gas and its implications for natural gas production and CO2 storage

International Nuclear Information System (INIS)

Seo, Young-ju; Park, Seongmin; Kang, Hyery; Ahn, Yun-Ho; Lim, Dongwook; Kim, Se-Joon; Lee, Jaehyoung; Lee, Joo Yong; Ahn, Taewoong; Seo, Yongwon; Lee, Huen

2016-01-01

Highlights: • The structural sustainability of sII hydrate is demonstrated during the replacement. • The experimental evidence of isostructural replacement is revealed. • The cage-specific replacement in sII hydrates allows long-term CO 2 storage. • The compositions and extent of replacement are cross-checked by GC and NMR analyses. - Abstract: A replacement technique has been regarded as a promising strategy for both CH 4 exploitation from gas hydrates and CO 2 sequestration into deep-ocean reservoirs. Most research has been focused on replacement reactions that occur in sI hydrates due to their prevalence in natural gas hydrates. However, sII hydrates in nature have been also discovered in some regions, and the replacement mechanism in sII hydrates significantly differs from that in sI hydrates. In this study, we have intensively investigated the replacement reaction of sII (C 3 H 8 + CH 4 ) hydrate by externally injecting CO 2 /N 2 (50:50) gas mixture with a primary focus on powder X-ray diffraction, Raman spectroscopy, NMR spectroscopy, and gas chromatography analyses. In particular, it was firstly confirmed that there was no structural transformation during the replacement of C 3 H 8 + CH 4 hydrate with CO 2 /N 2 gas injection, indicating that sII hydrate decomposition followed by sI hydrate formation did not occur. Furthermore, the cage-specific replacement pattern of the C 3 H 8 + CH 4 hydrate revealed that CH 4 replacement with N 2 in the small cages of sII was more significant than C 3 H 8 replacement with CO 2 in the large cages of sII. The total extent of the replacement for the C 3 H 8 + CH 4 hydrate was cross-checked by NMR and GC analyses and found to be approximately 54%. Compared to the replacement for CH 4 hydrate with CO 2 /N 2 gas, the lower extent of the replacement for the C 3 H 8 + CH 4 hydrate with CO 2 /N 2 gas was attributable to the persistent presence of C 3 H 8 in the large cages and the lower content of N 2 in the feed gas. The

Greenhouse gas balances of bioenergy systems: Programme and accomplishments of IEA Bioenergy Task XV, 1995-97

International Nuclear Information System (INIS)

Spitzer, J.

1998-01-01

The goal of IEA Bioenergy Task XV was to investigate all processes involved in using bioenergy systems, on a full fuel-cycle basis, with the aim of establishing overall greenhouse gas (GHG) balances. Task participants have been Austria, Canada, Finland, Sweden and the U.S.A. (Operating Agent: Austria). During its work period (1995-97), Task XV hosted five international workshops. The scientific achievements of the Task are documented in a number of published papers. Also, a bibliography on the research area was compiled. Much work was devoted to the question of carbon accounting in the context of the work of the Intergovernmental Panel on Climate Change (IPCC), and Task XV made contributions to a draft IPCC special report prepared for the IPCC Expert Group on Harvested Wood Products. The technical paper 'Forest harvests and wood products: sources and sinks of atmospheric carbon dioxide' (Forest Science, forthcoming) contrasts two carbon accounting approaches for considering wood products in the IPCC Guidelines (i.e., 'atmospheric-flow' vs. 'stock-change' method) and reports on estimated national carbon source-sink balances for selected countries, regions, and the world. Finally, progress was made in establishing a common analytical framework to compare different bioenergy options. The framework considers on-site carbon storage changes as well as GHG emissions from auxiliary fossil fuels, conversion efficiencies, and emission credits for by-products; comparisons between bioenergy systems and traditional fossil fuel and other energy systems as a reference are allowed, and reference land-uses accounted for. The continuation Task is Task 25 (1998-2000), with New Zealand joining the current partners 9 refs, 2 tabs

Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

International Nuclear Information System (INIS)

Sevigny, J.H.; Lintott, D.; Wrubleski, R.M.; Drury, C.R.

1997-01-01

The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox R toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox R toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox R toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent

Use of mass and toxicity balances in risk-based corrective action decisions at contaminated sites

Energy Technology Data Exchange (ETDEWEB)

Sevigny, J.H. [Komex Consultants Ltd., Calgary, AB (Canada); Lintott, D. [HydroQual Consultants, Inc., Calgary, AB (Canada); Wrubleski, R.M.; Drury, C.R. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre

1997-12-31

The contaminated groundwater at a sour gas plant facility was studied to identify the chemicals of environmental concern. Simple mass balance principles were used to determine the proportion of organic carbon, organic nitrogen and Microtox{sup R} toxicity that can be attributed to two process chemicals that have contaminated several sour gas plants in western Canada. The two process chemicals are sulfolane and diisopropanolamine (DIPA). The organic carbon balance was calculated by determining the molar contribution of sulfolane and DIPA relative to the mass of carboxylic acid-corrected dissolved organic carbon. Organic carbon balances ranged from 44 to 96 per cent. The organic nitrogen balance was calculated by determining the molar contribution of DIPA relative to the mass of ammonium ion-corrected dissolved Kjeldahl nitrogen. The nitrogen balances were highly variable between 8 to 48 per cent for samples with organic nitrogen concentrations between 10 and 32 mg/L. The Microtox{sup R} toxicity balance was calculated by determining the proportions of toxicity that could be accounted for by pure phase sulfolane and DIPA. The Microtox{sup R} toxicity balance for samples that showed significant toxicity ranged from 71 to 122 per cent.

Wii Fit balance training or progressive balance training in patients with chronic stroke: a randomised controlled trial

Science.gov (United States)

Yatar, Gozde Iyigun; Yildirim, Sibel Aksu

2015-01-01

[Purpose] The aim of this study was to compare the effects of Wii Fit balance training (WBT) and progressive balance training (PBT) approaches on balance functions, balance confidence, and activities of daily living in chronic stroke patients. [Subjects] A total of 30 patients were randomized into the WBT (n=15) and PBT (n=15) groups. [Methods] All of the subjects received exercise training based on a neurodevelopemental approach in addition to either Wii Fit or progressive balance training for total of 1 hour a day, 3 days per week for 4 weeks. Primary measurements were static balance function measured with a Wii Balance Board and dynamic balance function assessed with the Berg Balance Scale, Timed Up and Go test, Dynamic Gait Index, and Functional Reach Test. Secondary measures were balance confidence assessed with the Activities-specific Balance Confidence scale and activities of daily living evaluated with the Frenchay Activity Index. [Results] There was not remarkable difference between the two treatments in dynamic balance functions, balance confidence, and activities of daily living. [Conclusion] Although both of the approaches were found to be effective in improving the balance functions, balance confidence, and activities of daily living, neither of them were more preferable than the other for the treatment of balance in patients with chronic stroke. PMID:25995576

Wii Fit balance training or progressive balance training in patients with chronic stroke: a randomised controlled trial.

Science.gov (United States)

Yatar, Gozde Iyigun; Yildirim, Sibel Aksu

2015-04-01

[Purpose] The aim of this study was to compare the effects of Wii Fit balance training (WBT) and progressive balance training (PBT) approaches on balance functions, balance confidence, and activities of daily living in chronic stroke patients. [Subjects] A total of 30 patients were randomized into the WBT (n=15) and PBT (n=15) groups. [Methods] All of the subjects received exercise training based on a neurodevelopemental approach in addition to either Wii Fit or progressive balance training for total of 1 hour a day, 3 days per week for 4 weeks. Primary measurements were static balance function measured with a Wii Balance Board and dynamic balance function assessed with the Berg Balance Scale, Timed Up and Go test, Dynamic Gait Index, and Functional Reach Test. Secondary measures were balance confidence assessed with the Activities-specific Balance Confidence scale and activities of daily living evaluated with the Frenchay Activity Index. [Results] There was not remarkable difference between the two treatments in dynamic balance functions, balance confidence, and activities of daily living. [Conclusion] Although both of the approaches were found to be effective in improving the balance functions, balance confidence, and activities of daily living, neither of them were more preferable than the other for the treatment of balance in patients with chronic stroke.

The influence of diffusion and of reabsorption of radiation on the particle and energy balance of an infinitely long quasi-cylindrical discharge in hydrogen gas

International Nuclear Information System (INIS)

Goedheer, W.J.

1978-09-01

A numerical study of the pressure and temperature profiles of an infinitely long quasi-cylindrical discharge in hydrogen gas is presented. In particular the influence of the diffusion of atoms in the ground state and the reabsorption of Lyman-α and Lyman-β radiation on both the particle balance and the energy balance of the discharge is studied. Because the transport of the charged particles is corrected for toroidal effects in the regime of high collisionality which is present in the discharge, the model is quasi-cylindrical. The results obtained show an increase of the neutral density on the axis and of the ion and electron density near the wall of the discharge, as compared with earlier calculations in which both diffusion and reabsorption of radiation were neglected. The results are in agreement with measurements in the 'Ringboog' experiment. (Auth.)

Comparison of Gas Dehydration Methods based on Energy ...

African Journals Online (AJOL)

PROF HORSFALL

Natural Gas) dehydration to carry out the dehydration process and suitability of use on the basis of energy ... pipelines and distribution for burning by end users, natural gas must ... A good account of energy and material balance will create a ...

Synthesis gas production via hybrid steam reforming of natural gas and bio-liquids

OpenAIRE

Balegedde Ramachandran, P.

2013-01-01

This thesis deals with (catalytic) steam reforming of bio-liquids for the production of synthesis gas. Glycerol, both crude from the biodiesel manufacturing and refined, and pyrolysis oil are tested as bio-based feedstocks. Liquid bio-based feeds could be preferred over inhomogeneous fibrous solid biomass because of their logistic advantages, better mineral balance, and better processability. Especially the ease of pressurization, which is required for large scale synthesis gas production, is...

Balancing renewable electricity. Energy storage, demand side management, and network extension from an interdisciplinary perspective

Energy Technology Data Exchange (ETDEWEB)

Droste-Franke, Bert [Europaeische Akademie zur Erforschung von Folgen Wissenschaftlich-Technischer Entwicklungen GmbH, Bad Neuenahr-Ahrweiler (Germany); Paal, Boris P.; Rehtanz, Christian; Sauer, Dirk Uwe; Schneider, Jens-Peter; Schreurs, Miranda; Ziesemer, Thomas

2012-07-01

A significant problem of integrating renewable energies into the electricity system is the temporally fluctuating energy production by wind and solar power plants. Thus, in order to meet the ambitious long-term targets on CO{sub 2} emission reduction, long-term viable low-carbon options for balancing electricity will be needed. This interdisciplinary study analyses published future energy scenarios in order to get an impression of the required balancing capacities and shows which framework conditions should be modified to support their realisation. The authors combine their perspectives from energy engineering, technology assessment, political science, economical science and jurisprudence and address science, politics, actors in the energy sector and the interested public. Respectively, requirements for the balancing systems are analysed, considering the case of Germany as a large country with high ambitions to reduce greenhouse gas emissions. Additionally, an approach to investigate the optimal design of the technical system for balancing electricity over Europe is sketched. Looking at the challenges of a future energy system a mix of complementary technologies will prospectively become prevalent. In order to foster the needed innovation processes adequately, several funding mechanisms and legal regulations should be adapted. The authors give recommendations to handle major challenges in the development of the technical infrastructure, for the design of market conditions and for specific support of the application of balancing technologies. (orig.)

Conversion of hot coke oven gas into light fuel gas over Ni/Al{sub 2}O{sub 3} catalyst

Energy Technology Data Exchange (ETDEWEB)

Li, L.Y.; Morishita, K.; Takarada, T. [Gunma University, Gunma (Japan). Dept. of Biology & Chemical Engineering

2006-04-15

Conversion of hot coke oven gas (COG, containing tarry material) into light fuel gas over a Ni/Al{sub 2}O{sub 3} catalyst was studied. Laboratory scale tests were carried out in a two-stage fixed-bed reactor at ambient pressure. The nickel catalyst promoted the hydropyrolysis reaction of tarry materials. High yields of total product gas and methane were obtained at high hydrogen concentrations. If the hydrogen supply was adequate for hydropyrolysis of the tarry material, conversion of coal volatiles was high, at more than 95% on carbon balance, even with a gas residence time as short as 0.15 s in the catalyst bed. The product gas yield depended on catalytic temperature. At 923 K, the maximum conversion of coal volatiles into the light gas was achieved at 95.0% on carbon balance, with methane 86.7 vol% of the carbonaceous gas product. Although carbon deposits deactivated the catalyst after a long period of use, the catalyst could be regenerated by treatment with oxygen at 800 K, providing high activity in subsequent decomposition of tarry material. The influence of sulphide on the tarry material decomposition reaction was small even in a 2000 ppm H{sub 2}S atmosphere.

Effects of three methane mitigation agents on parameters of kinetics of total and hydrogen gas production, ruminal fermentation and hydrogen balance using in vitro technique.

Science.gov (United States)

Wang, Min; Wang, Rong; Yang, Shan; Deng, Jin Ping; Tang, Shao Xun; Tan, Zhi Liang

2016-02-01

Methane (CH4 ) can be mitigated through directly inhibiting methanogen activity and starving methanogens by hydrogen (H2 ) sink. Three types of mechanism (i.e. bromoethanesulphonate (BES), nitrate and emodin) and doses of CH4 mitigation agents were employed to investigate their pathways of CH4 inhibition. Results indicated that both BES and emodin inhibited CH4 production and altered H2 balance, which could be accompanied by decreased dry matter disappearance (DMD), fractional rate of gH2 formation, volatile fatty acid (VFA) production, ability to produce and use reducing equivalences and molecular H2 , and increased final asymptotic gH2 production, time to the peak of gH2 , discrete lag time of gH2 production and fermentation efficiency. However, emodin decreased gas volume produced by rapidly fermentable components of substrate and the rate of fermentation at early stage of incubation, while BES supplementation inhibited gas volume produced by both rapidly and slowly fermentable components of substrate and the rate of fermentation at middle or late stage of incubation. The nitrate supplementation inhibited CH4 production without affecting VFA profile, because of its dual role as H2 sink and being toxic to methanogens. Nitrate supplementation had more complicated pattern of fermentation, VFA production and profile and H2 balance in comparison to BES and emodin supplementation. © 2015 Japanese Society of Animal Science.

The effect of Sphagnum farming on the greenhouse gas balance of donor and propagation areas, irrigation polders and commercial cultivation sites

Science.gov (United States)

Oestmann, Jan; Tiemeyer, Bärbel

2017-04-01

Drainage of peatlands for agriculture, forestry and peat extraction turned these landscapes into hotspots of greenhouse gas emissions. Climate protection now fosters rewetting projects to restore the natural peatland function as a sink of atmospheric carbon. One possible way to combine ecological and economical goals is Sphagnum farming, i.e. the cultivation of Sphagnum mosses as high-quality substrates for horticulture. This project scientifically evaluates the attempt of commercial Sphagnum farming on former peat extraction sites in north-western Germany. The exchange of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) of the whole peatland-based production chain comprising a donor mire, a propagation area, an irrigation polder and a cultivation site will be determined in a high temporal resolution for two years using manual chambers. This will allow evaluating the greenhouse gas balance of Sphagnum farming sites in comparison to near-natural sites and the potential of Sphagnum farming for restoring drained peatlands to sinks of atmospheric carbon. The influence of different irrigation techniques will also be tested. Additionally, selected plots will be equipped with open top chambers in order to examine the greenhouse gas exchange under potential future climate change conditions. Finally, a 13C pulse labeling experiment will make it possible to trace the newly sequestered CO2 in biomass, soil, respiration and dissolved organic carbon.

Midwest gas and power markets, hubs, pipelines, and interconnects

International Nuclear Information System (INIS)

Wirick, J.

2001-01-01

The existing interstate pipelines and proposed pipeline projects for the Chicago hub area were illustrated. The presentation explained why energy suppliers in the current competitive market need to balance and manage energy and transportation services for gas-fired power generators in terms of hourly winter and summer peaking services. The new infrastructure of the energy market will include new pipelines, storage and balancing to meet the ever increasing power demand. One of the options to meet power demand is to increase natural gas supply, transportation, storage, and hourly balancing capabilities. Other options are to build nuclear or coal-fired power generating facilities, or to go with renewables such as solar and wind power. Energy conservation and the reduction of natural gas usage per capita is another option to eliminate blackouts. This presentation also addressed the role that local distribution companies (LDC) and unbundling will play in the choice of these options. tabs., figs

Blood gas analysis, anion gap, and strong ion difference in horses treated with polyethylene glycol balanced solution (PEG 3350 or enteral and parenteral electrolyte solutions

Directory of Open Access Journals (Sweden)

Cláudio Luís Nina Gomes

2014-06-01

Full Text Available Large volumes of different electrolytes solutions are commonly used for ingesta hydration in horses with large colon impaction, but little is known about their consequences to blood acid-base balance. To evaluate the effects of PEG 3350 or enteral and parenteral electrolyte solutions on the blood gas analysis, anion gap and strong ion difference, five adult female horses were used in a 5x5 latin square design. The animals were divided in five groups and distributed to each of the following treatments: NaCl (0.9% sodium chloride solution; EES (enteral electrolyte solution, EES+LR (EES plus lactated Ringer's solution; PEG (balanced solution with PEG 3350 and PEG+LR (PEG plus lactated Ringer's solution. Treatments PEG or PEG + LR did not change or promoted minimal changes, while the EES caused a slight decrease in pH, but its association with lactated Ringer's solution induced increase in AG and SID values, as well as caused hypernatremia. In turn, the treatment NaCl generated metabolic acidosis. PEG 3350 did not alter the acid-base balance. Despite it's slight acidifying effect, the enteral electrolyte solution (EES did not cause clinically relevant changes.

Energy balance, greenhouse gas emissions, and profitability of thermobarical pretreatment of cattle waste in anaerobic digestion.

Science.gov (United States)

Budde, Jörn; Prochnow, Annette; Plöchl, Matthias; Suárez Quiñones, Teresa; Heiermann, Monika

2016-03-01

In this study modeled full scale application of thermobarical hydrolysis of less degradable feedstock for biomethanation was assessed in terms of energy balance, greenhouse gas emissions, and economy. Data were provided whether the substitution of maize silage as feedstock for biogas production by pretreated cattle wastes is beneficial in full-scale application or not. A model device for thermobarical treatment has been suggested for and theoretically integrated in a biogas plant. The assessment considered the replacement of maize silage as feedstock with liquid and/or solid cattle waste (feces, litter, and feed residues from animal husbandry of high-performance dairy cattle, dry cows, and heifers). The integration of thermobarical pretreatment is beneficial for raw material with high contents of organic dry matter and ligno-cellulose: Solid cattle waste revealed very short payback times, e.g. 9 months for energy, 3 months for greenhouse gases, and 3 years 3 months for economic amortization, whereas, in contrast, liquid cattle waste did not perform positive replacement effects in this analysis. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Blood gas analysis, anion gap, and strong ion difference in horses treated with polyethylene glycol balanced solution (PEG 3350) or enteral and parenteral electrolyte solutions

OpenAIRE

Gomes, Cláudio Luís Nina; Ribeiro Filho, José Dantas; Faleiros, Rafael Resende; Dantas, Fernanda Timbó D'el Rey; Amorim, Lincoln da Silva; Dantas, Waleska de Melo Ferreira

2014-01-01

Large volumes of different electrolytes solutions are commonly used for ingesta hydration in horses with large colon impaction, but little is known about their consequences to blood acid-base balance. To evaluate the effects of PEG 3350 or enteral and parenteral electrolyte solutions on the blood gas analysis, anion gap and strong ion difference, five adult female horses were used in a 5x5 latin square design. The animals were divided in five groups and distributed to each of the following tr...

AN INITIAL EVALUATION OF THE BTRACKS BALANCE PLATE AND SPORTS BALANCE SOFTWARE FOR CONCUSSION DIAGNOSIS.

Science.gov (United States)

Goble, Daniel J; Manyak, Kristin A; Abdenour, Thomas E; Rauh, Mitchell J; Baweja, Harsimran S

2016-04-01

As recently dictated by the American Medical Society, balance testing is an important component in the clinical evaluation of concussion. Despite this, previous research on the efficacy of balance testing for concussion diagnosis suggests low sensitivity (∼30%), based primarily on the popular Balance Error Scoring System (BESS). The Balance Tracking System (BTrackS, Balance Tracking Systems Inc., San Diego, CA, USA) consists of a force plate (BTrackS Balance Plate) and software (BTrackS Sport Balance) which can quickly (balance testing with gold standard accuracy. The present study aimed to determine the sensitivity of the BTrackS Balance Plate and Sports Balance Software for concussion diagnosis. Cross-Sectional Study. Preseason baseline balance testing of 519 healthy Division I college athletes playing sports with a relatively high risk for concussions was performed with the BTrackS Balance Test. Testing was administered by certified athletic training staff using the BTrackS Balance Plate and Sport Balance software. Of the baselined athletes, 25 later experienced a concussion during the ensuing sport season. Post-injury balance testing was performed on these concussed athletes within 48 of injury and the sensitivity of the BTrackS Balance Plate and Sport Balance software was estimated based on the number of athletes showing a balance decline according to the criteria specified in the Sport Balance software. This criteria is based on the minimal detectable change statistic with a 90% confidence level (i.e. 90% specificity). Of 25 athletes who experienced concussions, 16 had balance declines relative to baseline testing results according to the BTrackS Sport Balance software criteria. This corresponds to an estimated concussion sensitivity of 64%, which is twice as great as that reported previously for the BESS. The BTrackS Balance Plate and Sport Balance software has the greatest concussion sensitivity of any balance testing instrument reported to date. Level 2

Thermal balance of a four stroke SI engine operating on hydrogen as a supplementary fuel

International Nuclear Information System (INIS)

Yueksel, F.; Ceviz, M.A.

2003-01-01

This paper investigates the effects of adding constant quantity hydrogen to gasoline-air mixture on SI engine thermal balance and performance. A four stroke, four-cylinder SI engine was used for conducting this study. Thermal balance tests were conducted for engine thermal efficiency, heat loss through the exhaust gases, heat loss to the cooling water and unaccounted losses (i.e. heat lost by lubricating oil, radiation), while performance tests were in respect to the brake power, specific fuel consumption and air ratio. Hydrogen supplementations were used with three different and fixed mass flow rates; 0.129, 0.168 and 0.208 kg h -1 at near three-fourth throttle opening position and variable engine speed ranging from 1000 to 4500 rpm. The results showed that supplementation of hydrogen to gasoline decreases the heat loss to cooling water and unaccounted losses, and the heat loss through the exhaust gas is nearly the same with pure gasoline experiments. Additionally, specific fuel consumption decreases, while the engine thermal efficiency and the air ratio increase. Engine performance parameters such as thermal efficiency and specific fuel consumption improved the level of the ratio of hydrogen mass flow rate to that of gasoline up to 5%

Global gas balance and influence of atomic hydrogen irradiation on the wall inventory in steady-state operation of QUEST tokamak

Science.gov (United States)

Kuzmin, A.; Zushi, H.; Takagi, I.; Sharma, S. K.; Rusinov, A.; Inoue, Y.; Hirooka, Y.; Zhou, H.; Kobayashi, M.; Sakamoto, M.; Hanada, K.; Yoshida, N.; Nakamura, K.; Fujisawa, A.; Matsuoka, K.; Idei, H.; Nagashima, Y.; Hasegawa, M.; Onchi, T.; Banerjee, S.; Mishra, K.

2015-08-01

Hydrogen wall pumping is studied in steady state tokamak operation (SSTO) of QUEST with all metal plasma facing materials PFMs at 100 °C. The duration of SSTO is up to 820 s in fully non-inductive plasma. Global gas balance analysis shows that wall pumping at the apparent (retention-release) rate of 1-6 × 1018 H/s is dominant and 70-80% of injected H2 can be retained in PFMs. However, immediately after plasma termination the H2 release rate enhances to ∼1019 H/s. In order to understand a true retention process the direct measurement of retention flux has been carried out by permeation probes. The comparison between the evaluated wall retention and results from global analysis is discussed.

Computational Fluid Dynamics-Population Balance Model Simulation of Effects of Cell Design and Operating Parameters on Gas-Liquid Two-Phase Flows and Bubble Distribution Characteristics in Aluminum Electrolysis Cells

Science.gov (United States)

Zhan, Shuiqing; Wang, Junfeng; Wang, Zhentao; Yang, Jianhong

2018-02-01

The effects of different cell design and operating parameters on the gas-liquid two-phase flows and bubble distribution characteristics under the anode bottom regions in aluminum electrolysis cells were analyzed using a three-dimensional computational fluid dynamics-population balance model. These parameters include inter-anode channel width, anode-cathode distance (ACD), anode width and length, current density, and electrolyte depth. The simulations results show that the inter-anode channel width has no significant effect on the gas volume fraction, electrolyte velocity, and bubble size. With increasing ACD, the above values decrease and more uniform bubbles can be obtained. Different effects of the anode width and length can be concluded in different cell regions. With increasing current density, the gas volume fraction and electrolyte velocity increase, but the bubble size keeps nearly the same. Increasing electrolyte depth decreased the gas volume fraction and bubble size in particular areas and the electrolyte velocity increased.

Emission model for landfills with mechanically-biologically pretreated waste, with the emphasis on modelling the gas balance; Emissionsprognosemodell fuer Deponien mit mechanisch-biologisch vorbehandelten Abfaellen - Schwerpunkt: Modellierung des Gashaushaltes

Energy Technology Data Exchange (ETDEWEB)

Danhamer, H.

2001-07-01

The objective of this work was to determine influence factors on processes going on in landfills with mechanically-biologically pretreated waste (MBP-landfills) in order to predict emissions. For this purpose a computer based model has been developed. The model allows to simulate the gas, water and heat balance as well as settlement processes and was called DESIM2005 (version MB). It is based on theoretical modeling approaches as well as data from lab and reactor experiments. The main focus of model application was to determine factors influencing the gas phase and the emissions of landfill gas and methane during operation and aftercare of MBP-landfills. By performing simulations the effects of changing parameters for the processes gas transport and biological degradation as well as the effects of different qualities in waste pretreatment and of varying landfill operation techniques were investigated. Possibilities for increasing the environmental sustainability of landfills containing mechanically-biologically pretreated waste were shown. (orig.)

Associations of Walking Speed, Grip Strength, and Standing Balance With Total and Cause-Specific Mortality in a General Population of Japanese Elders.

Science.gov (United States)

Nofuji, Yu; Shinkai, Shoji; Taniguchi, Yu; Amano, Hidenori; Nishi, Mariko; Murayama, Hiroshi; Fujiwara, Yoshinori; Suzuki, Takao

2016-02-01

Walking speed, grip strength, and standing balance are key components of physical performance in older people. The present study aimed to evaluate (1) associations of these physical performance measures with cause-specific mortality, (2) independent associations of individual physical performance measures with mortality, and (3) the added value of combined use of the 3 physical performance measures in predicting all-cause and cause-specific mortality. Prospective cohort study with a follow-up of 10.5 years. Tokyo Metropolitan Institute of Gerontology Longitudinal Interdisciplinary Study on Aging (TMIG-LISA), Japan. A total of 1085 initially nondisabled older Japanese aged 65 to 89 years. Usual walking speed, grip strength, and standing balance were measured at baseline survey. During follow-up, 324 deaths occurred (122 of cardiovascular disease, 75 of cancer, 115 of other causes, and 12 of unknown causes). All 3 physical performance measures were significantly associated with all-cause, cardiovascular, and other-cause mortality, but not with cancer mortality, independent of potential confounders. When all 3 physical performance measures were simultaneously entered into the model, each was significantly independently associated with all-cause and cardiovascular mortality. The C statistics for all-cause and cardiovascular mortality were significantly increased by adding grip strength and standing balance to walking speed (P balance predicted all-cause, cardiovascular, and other-cause mortality, but not cancer mortality, independent of covariates. Moreover, these 3 components of physical performance were independently associated with all-cause and cardiovascular mortality and their combined use increased prognostic power. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Emission reductions through precombustion chamber design in a natural gas, lean burn engine

International Nuclear Information System (INIS)

Crane, M.E.; King, S.R.

1992-01-01

A study was conducted to evaluate the effects of various precombustion chamber design, operating and control parameters on the exhaust emissions of a natural gas engine. Analysis of the results showed that engine-out total hydrocarbons and oxides of nitrogen (NO x ) can be reduced, relative to conventional methods, through prechamber design. More specifically, a novel staged prechamber yielded significant reductions in NO x and total hydrocarbon emissions by promoting stable prechamber and main chamber ignition under fuel-lean conditions. Precise fuel control was also critical when balancing low emissions and engine efficiency (i.e., fuel economy). The purpose of this paper is to identify and explain positive and deleterious effects of natural gas prechamber design on exhaust emissions

Method for Balancing Detector Output to a Desired Level of Balance at a Frequency

Science.gov (United States)

Sachse, Glenn W. (Inventor)

2003-01-01

A multi-gas sensor is provided which modulates a polarized light beam over a broadband of wavelengths between two alternating orthogonal polarization components. The two orthogonal polarization components of the polarization modulated beam are directed along two distinct optical paths. At least one optical path contains one or more spectral discrimination elements, with each spectral discrimination element having spectral absorption features of one or more gases of interest being measured. The two optical paths then intersect, and one orthogonal component of the intersected components is transmitted and the other orthogonal component is reflected. The combined polarization modulated beam is partitioned into one or more smaller spectral regions of interest where one or more gases of interest has an absorption band. The difference in intensity between the two orthogonal polarization components is then determined in each partitioned spectral region of interest as an indication of the spectral emission/absorption of the light beam by the gases of interest in the measurement path. The spectral emission/absorption is indicative of the concentration of the one or more gases of interest in the measurement path. More specifically, one embodiment of the present invention is a gas filter correlation radiometer which comprises a polarizer, a polarization modulator, a polarization beam splitter, a beam combiner, wavelength partitioning element, and detection element. The gases of interest are measured simultaneously and, further, can be measured independently or non-independently. Furthermore, optical or electronic element are provided to balance optical intensities between the two optical paths.

Specifically agricultural fuel: manure gas

Energy Technology Data Exchange (ETDEWEB)

Ducellier, G; Isman, M

1947-01-01

By means of an appropriate succession of thermogenic, neutralizing, and CH/sub 4/-producing fermentations, 1 ton dry straw can produce up to 300 m/sup 3/ of combustible gas containing 60 to 70% CH/sub 4/ and 30 to 40% CO/sub 2/, and having a calorific value of 6000 cal per m/sup 3/. It has the advantage of being nontoxic, as it contains no CO, and of being only slightly explosive at ordinary pressure. Its advantages on the farm are briefly discussed.

Load Balancing Scientific Applications

Energy Technology Data Exchange (ETDEWEB)

Pearce, Olga Tkachyshyn [Texas A & M Univ., College Station, TX (United States)

2014-12-01

The largest supercomputers have millions of independent processors, and concurrency levels are rapidly increasing. For ideal efficiency, developers of the simulations that run on these machines must ensure that computational work is evenly balanced among processors. Assigning work evenly is challenging because many large modern parallel codes simulate behavior of physical systems that evolve over time, and their workloads change over time. Furthermore, the cost of imbalanced load increases with scale because most large-scale scientific simulations today use a Single Program Multiple Data (SPMD) parallel programming model, and an increasing number of processors will wait for the slowest one at the synchronization points. To address load imbalance, many large-scale parallel applications use dynamic load balance algorithms to redistribute work evenly. The research objective of this dissertation is to develop methods to decide when and how to load balance the application, and to balance it effectively and affordably. We measure and evaluate the computational load of the application, and develop strategies to decide when and how to correct the imbalance. Depending on the simulation, a fast, local load balance algorithm may be suitable, or a more sophisticated and expensive algorithm may be required. We developed a model for comparison of load balance algorithms for a specific state of the simulation that enables the selection of a balancing algorithm that will minimize overall runtime.

Site-specific fragmentation of polystyrene molecule using size-selected Ar gas cluster ion beam

International Nuclear Information System (INIS)

Moritani, Kousuke; Mukai, Gen; Hashinokuchi, Michihiro; Mochiji, Kozo

2009-01-01

The secondary ion mass spectrum (SIMS) of a polystyrene thin film was investigated using a size-selected Ar gas cluster ion beam (GCIB). The fragmentation in the SIM spectrum varied by kinetic energy per atom (E atom ); the E atom dependence of the secondary ion intensity of the fragment species of polystyrene can be essentially classified into three types based on the relationship between E atom and the dissociation energy of a specific bonding site in the molecule. These results indicate that adjusting E atom of size-selected GCIB may realize site-specific bond breaking within a molecule. (author)

Demand and supply in Russian gas market

International Nuclear Information System (INIS)

Milovidov, K.N.

1997-01-01

The big volume of gas supplies for current and future energy and natural gas balances in Russia is important to understand the likely future dynamics of demand for gas. The path of future demand in Russia is uncertain and the range of possible scenarios is wide. For creating the new gas consumption structure, more deep diversification and development of the gas distribution systems, large investments and considerable periods of time are necessary. The factors usually studied in detail in the conditions of market economy can not be used here as a basis for strategic planning due to several reasons. (R.P.)

Investigation of gas flow characteristics in proton exchange membrane fuel cell

International Nuclear Information System (INIS)

Kwac, Lee Ku; Kim, Hong Gun

2008-01-01

An investigation of electrochemical behavior of PEMFC (proton exchange membrane fuel cell) is performed by using a single-phase two-dimensional finite element analysis. Equations of current balance, mass balance, and momentum balance are implemented to simulate the behavior of PEMFC. The analysis results for the co-flow and counterflow mode of gas flow direction are examined in detail in order to compare how the gas flow direction affects quantitatively. The characteristics of internal properties, such as gas velocity distribution, mass fraction of the reactants, fraction of water and current density distribution in PEMFC are illustrated in the electrode and GDL (gas diffusion layer). It is found that the dry reactant gases can be well internally humidified and maintain high performance in the case of the counter-flow mode without external humidification while it is not advantageous for highly humidified or saturated reactant gases. It is also found that the co-flow mode improves the current density distribution with humidified normal condition compared to the counter-flow mode

Radiation balances and the solar constant

Science.gov (United States)

Crommelynck, D.

1981-01-01

The radiometric concepts are defined in order to consider various types of radiation balances and relate them to the diabetic form of the energy balance. Variability in space and time of the components of the radiation field are presented. A specific concept for sweeping which is tailored to the requirements is proposed. Finally, after establishing the truncated character of the present knowledge of the radiation balance. The results of the last observations of the solar constant are given. Ground and satellite measurement techniques are discussed.

The Impact of Trade Balance in the Current Account of Kosovo’s Balance of Payments

Directory of Open Access Journals (Sweden)

Safet Merovci

2014-02-01

Full Text Available The trade deficit and specifically the current account deficit are the main challenges that Kosovo‘s economy is facing. According to the Balance of Payments Statistics (BOP, the trade balance of goods is the largest component, expressed in absolute and relative terms and consequently it determines the behavior of the current account balance. Trade deficit to GDP ratio is very high - more than 50 percent. Regarding this, financing the constant deficit of the current account is becoming a real problem, because in the long run it is impossible for a country to spend more than its income without becoming a debtor to the rest of the world. Given the unchanged structure of the current account of the Balance of Payments, we conclude that, an improvement of the trade balance is a precondition to the improvement of the current account balance. This can be done through longterm and sustainable substitution of imports with domestic production and also with effective export promotion. Increasing foreign direct investment and export promotion can be considered, in the longer term, the main way to improve Kosovo's Trade Balance.

Global gas balance and influence of atomic hydrogen irradiation on the wall inventory in steady-state operation of QUEST tokamak

Energy Technology Data Exchange (ETDEWEB)

Kuzmin, A., E-mail: kuzmin@triam.kyushu-u.ac.jp [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Zushi, H. [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Takagi, I. [Graduate School of Engineering, Kyoto University (Japan); Sharma, S.K. [Institute for Plasma Research, Ahmadabad, Gujrat (India); Rusinov, A. [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Inoue, Y. [IGSES, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Hirooka, Y. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Zhou, H. [Graduate School for Advanced Studies, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Kobayashi, M. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Sakamoto, M. [Plasma Research Center, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 (Japan); Hanada, K.; Yoshida, N.; Nakamura, K.; Fujisawa, A.; Matsuoka, K.; Idei, H.; Nagashima, Y.; Hasegawa, M.; Onchi, T. [RIAM, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); Banerjee, S. [IGSES, Kyushu University, 6-1 Kasugakoen, Kasuga, Fukuoka 816-8580 (Japan); and others

2015-08-15

Hydrogen wall pumping is studied in steady state tokamak operation (SSTO) of QUEST with all metal plasma facing materials PFMs at 100 °C. The duration of SSTO is up to 820 s in fully non-inductive plasma. Global gas balance analysis shows that wall pumping at the apparent (retention–release) rate of 1–6 × 10{sup 18} H/s is dominant and 70–80% of injected H{sub 2} can be retained in PFMs. However, immediately after plasma termination the H{sub 2} release rate enhances to ∼10{sup 19} H/s. In order to understand a true retention process the direct measurement of retention flux has been carried out by permeation probes. The comparison between the evaluated wall retention and results from global analysis is discussed.

Global gas balance and influence of atomic hydrogen irradiation on the wall inventory in steady-state operation of QUEST tokamak

International Nuclear Information System (INIS)

Kuzmin, A.; Zushi, H.; Takagi, I.; Sharma, S.K.; Rusinov, A.; Inoue, Y.; Hirooka, Y.; Zhou, H.; Kobayashi, M.; Sakamoto, M.; Hanada, K.; Yoshida, N.; Nakamura, K.; Fujisawa, A.; Matsuoka, K.; Idei, H.; Nagashima, Y.; Hasegawa, M.; Onchi, T.; Banerjee, S.

2015-01-01

Hydrogen wall pumping is studied in steady state tokamak operation (SSTO) of QUEST with all metal plasma facing materials PFMs at 100 °C. The duration of SSTO is up to 820 s in fully non-inductive plasma. Global gas balance analysis shows that wall pumping at the apparent (retention–release) rate of 1–6 × 10 18 H/s is dominant and 70–80% of injected H 2 can be retained in PFMs. However, immediately after plasma termination the H 2 release rate enhances to ∼10 19 H/s. In order to understand a true retention process the direct measurement of retention flux has been carried out by permeation probes. The comparison between the evaluated wall retention and results from global analysis is discussed

Assessing the Greenhouse Gas Emissions from Natural Gas Fired Power Plants

Science.gov (United States)

Hajny, K. D.; Shepson, P. B.; Rudek, J.; Stirm, B. H.; Kaeser, R.; Stuff, A. A.

2017-12-01

Natural gas is often discussed as a "bridge fuel" to transition to renewable energy as it only produces 51% the amount of CO2 per unit energy as coal. This, coupled with rapid increases in production fueled by technological advances, has led to a near tripling of natural gas used for electricity generation since 2005. One concern with this idea of a "bridge fuel" is that methane, the primary component of natural gas, is itself a potent greenhouse gas with 28 and 84 times the global warming potential of CO2 based on mass over a 100 and 20 year period, respectively. Studies have estimated that leaks from the point of extraction to end use of 3.2% would offset the climate benefits of natural gas. Previous work from our group saw that 3 combined cycle power plants emitted unburned CH4 from the stacks and leaked additional CH4 from equipment on site, but total loss rates were still less than 2.2%. Using Purdue's Airborne Laboratory for Atmospheric Research (ALAR) we completed additional aircraft based mass balance experiments combined with passes directly over power plant stacks to expand on the previous study. In this work, we have measured at 12 additional natural gas fired power plants including a mix of operation types (baseload, peaking, intermediate) and firing methods (combined cycle, simple thermal, combustion turbine). We have also returned to the 3 plants previously sampled to reinvestigate emissions for each of those, to assess reproducibility of the results. Here we report the comparison of reported continuous emissions monitoring systems (CEMS) data for CO2 to our emission rates calculated from mass balance experiments, as well as a comparison of calculated CH4 emission rates to estimated emission rates based on the EPA emission factor of 1 g CH4/mmbtu natural gas and CEMS reported heat input. We will also discuss emissions from a coal-fired plant which has been sampled by the group in the past and has since converted to natural gas. Lastly, we discuss the

Greenhouse gas balance of an establishing Sphagnum culture on a former bog grassland in Germany

Directory of Open Access Journals (Sweden)

A. Günther

2017-04-01

Full Text Available The cultivation of Sphagnum mosses on re-wetted peat bogs for use in horticulture is a new land use strategy. We provide the first greenhouse gas balances for a field-scale Sphagnum farming experiment on former bog grassland, in its establishment phase. Over two years we used closed chambers to make measurements of GHG exchange on production strips of Sphagnum palustre L. and Sphagnum papillosum Lindb. and on irrigation ditches. Methane fluxes of both Sphagnum species showed a significant decrease over the study period. This trend was stronger for S. papillosum. In contrast, the estimated CO2 fluxes did not show a significant temporal trend over the study period. The production strips of both Sphagnum species were net GHG sinks of 5–9 t ha 1 a 1 (in CO2-equivalents during the establishment phase of the moss carpets. In comparison, the ditches were a CO2 source instead of a CO2 sink and emitted larger amounts of CH4, resulting in net GHG release of ~11 t ha 1 a 1 CO2-equivalents. We conclude that Sphagnum farming fields should be designed to minimise the area covered by irrigation ditches. Overall, Sphagnum farming on bogs has lower on-field GHG emissions than low-intensity agriculture.

Analysis of gob gas venthole production performances for strata gas control in longwall mining.

Science.gov (United States)

Karacan, C Özgen

2015-10-01

Longwall mining of coal seams affects a large area of overburden by deforming it and creating stress-relief fractures, as well as bedding plane separations, as the mining face progresses. Stress-relief fractures and bedding plane separations are recognized as major pathways for gas migration from gas-bearing strata into sealed and active areas of the mines. In order for strata gas not to enter and inundate the ventilation system of a mine, gob gas ventholes (GGVs) can be used as a methane control measure. The aim of this paper is to analyze production performances of GGVs drilled over a longwall panel. These boreholes were drilled to control methane emissions from the Pratt group of coals due to stress-relief fracturing and bedding plane separations into a longwall mine operating in the Mary Lee/Blue Creek coal seam of the Upper Pottsville Formation in the Black Warrior Basin, Alabama. During the course of the study, Pratt coal's reservoir properties were integrated with production data of the GGVs. These data were analyzed by using material balance techniques to estimate radius of influence of GGVs, gas-in-place and coal pressures, as well as their variations during mining. The results show that the GGVs drilled to extract gas from the stress-relief zone of the Pratt coal interval is highly effective in removing gas from the Upper Pottsville Formation. The radii of influence of the GGVs were in the order of 330-380 m, exceeding the widths of the panels, due to bedding plane separations and stress relieved by fracturing. Material balance analyses indicated that the initial pressure of the Pratt coals, which was around 648 KPa when longwall mining started, decreased to approximately 150 KPa as the result of strata fracturing and production of released gas. Approximately 70% of the initial gas-in-place within the area of influence of the GGVs was captured during a period of one year.

Successful generation of primary virus-specific and anti-tumor T-cell responses from the naive donor T-cell repertoire is determined by the balance between antigen-specific precursor T cells and regulatory T cells.

NARCIS (Netherlands)

Jedema, I.; Meent, M. van de; Pots, J.M.; Kester, M.G.; Beek, M.T. van der; Falkenburg, J.H.F.

2011-01-01

BACKGROUND: One of the major challenges in allogeneic stem cell transplantation is to find a balance between the harmful induction of graft-versus-host disease and the beneficial graft-versus-leukemia and pathogen-specific immune responses. Adoptive transfer of in-vitro generated donor T cells with

Practical Results of Forecasting for the Natural Gas Market

OpenAIRE

Potocnik, Primoz; Govekar, Edvard

2010-01-01

Natural gas consumption forecasting is required to balance the supply and consumption of natural gas. Companies and natural gas distributors are motivated to forecast their consumption by the economic incentive model that dictates the cash flow rules corresponding to the forecasting accuracy. The rules are quite challenging but enable the company to gain positive cash flow by forecasting accurately their short-term natural gas consumption. In this chapter, some practical forecasting results f...

Home-based balance training programme using Wii Fit with balance board for Parkinsons's disease: a pilot study.

Science.gov (United States)

Esculier, Jean-Francois; Vaudrin, Joanie; Bériault, Patrick; Gagnon, Karine; Tremblay, Louis E

2012-02-01

To evaluate the effects of a home-based balance training programme using visual feedback (Nintendo Wii Fit game with balance board) on balance and functional abilities in subjects with Parkinson's disease, and to compare the effects with a group of paired healthy subjects. Ten subjects with moderate Parkinson's disease and 8 healthy elderly subjects. Subjects participated in a 6-week home-based balance training programme using Nintendo Wii Fit and balance board. Baseline measures were taken before training for the Sit-to-Stand test (STST), Timed-Up-and-Go (TUG), Tinetti Performance Oriented Mobility Assessment (POMA), 10-m walk test, Community Balance and Mobility assessment (CBM), Activities-specific Balance and Confidence scale (ABC), unipodal stance duration, and a force platform. All measurements were taken again after 3 and 6 weeks of training. The Parkinson's disease group significantly improved their results in TUG, STST, unipodal stance, 10-m walk test, CBM, POMA and force platform at the end of the 6-week training programme. The healthy subjects group significantly improved in TUG, STST, unipodal stance and CBM. This pilot study suggests that a home-based balance programme using Wii Fit with balance board could improve static and dynamic balance, mobility and functional abilities of people affected by Parkinson's disease.

Offshore wind energy : balancing risk and reward

International Nuclear Information System (INIS)

Nerland, C.

2010-01-01

Offshore wind energy developments are expected to increase as the demand for renewable energy sources grows. This poster presentation described a method of balancing risk and reward in offshore wind energy projects. The method was based on risk assessment strategies used by the oil and gas industry. The dedicated framework considered schedules; budgets; performance; and operating and maintenance costs. A value chain assessment method was used to optimize the balance between risk and reward by evaluating uncertainties and risk related to each project element and its relationship to other elements within an integrated dynamic model designed to determine the net present value of a project. The decision-making criteria included the RISKEX risk expenditure strategy designed to consider the balance between risk exposure, capital expenditures, and operational expenditures in relation to the statistical cost of unplanned repairs, and lost production capacity. A case study of a large offshore wind farm was used to demonstrate the method. tabs., figs.

1997-98 statistical data of the natural gas industry in France

International Nuclear Information System (INIS)

1999-01-01

This document summarizes the main economical results of the natural gas industry sector in France for 1997 and 1998. An overview of the gas market is also given (natural gas, LPG, fire damp gas, etc..). Several statements are provided for the natural gas: sectoral analysis of consumptions, number of consumers and amount of supplies, personnel status of the natural gas industry, consumptions in the industry, share of natural gas in the French energy balance sheet.. (J.S.)

Influence of reactive gas admixture on transition metal cluster nucleation in a gas aggregation cluster source

Science.gov (United States)

Peter, Tilo; Polonskyi, Oleksandr; Gojdka, Björn; Mohammad Ahadi, Amir; Strunskus, Thomas; Zaporojtchenko, Vladimir; Biederman, Hynek; Faupel, Franz

2012-12-01

We quantitatively assessed the influence of reactive gases on the formation processes of transition metal clusters in a gas aggregation cluster source. A cluster source based on a 2 in. magnetron is used to study the production rate of titanium and cobalt clusters. Argon served as working gas for the DC magnetron discharge, and a small amount of reactive gas (oxygen and nitrogen) is added to promote reactive cluster formation. We found that the cluster production rate depends strongly on the reactive gas concentration for very small amounts of reactive gas (less than 0.1% of total working gas), and no cluster formation takes place in the absence of reactive species. The influence of discharge power, reactive gas concentration, and working gas pressure are investigated using a quartz micro balance in a time resolved manner. The strong influence of reactive gas is explained by a more efficient formation of nucleation seeds for metal-oxide or nitride than for pure metal.

Layout of an internally heated gas generator for the steam gasification of coal

International Nuclear Information System (INIS)

Feistel, P.P.; Duerrfeld, R.; Heck, K.H. van; Juentgen, H.

1975-01-01

Industrial-scale steam gasification of coal using heat from high temperature reactors requires research and development on allothermal gas generators. Bergbau-Forschung GmbH, Essen, does theoretical and experimental work in this field. The experiments deal with reaction kinetics, heat transfer and material tests. Their significance for the layout of a full-scale gas generator is shown. Including material specifications, the feasibility of a gasifier, characterized by a fluid bed volume of 318 m 3 and a heat transferring area of 4000 m 2 , results. The data, now available, are used to determine the gasification throughput from the heat balance, i.e. the equality of heat consumed and heat transferred. Throughputs of about 50 t/hr of coal are possible for a single gas generator, the helium outlet temperature of the HTR being 950 0 C/ Bergbau-Forschung has commissioned a medium-scale pilot plant (200 kg/hr). (Auth.)

NGL component tracking and balancing : a producer perspective

International Nuclear Information System (INIS)

Brown, D.

1999-01-01

The issue of whether NGL producers in Alberta will transport their NGLs in liquid form or in the more economic gaseous form was discussed. The answer will depend on whether the industry can develop a cost effective component tracking infrastructure and negotiate a fair component balancing methodology which will allow shippers to be kept whole on each of their NGL components. Component tracking would measure the energy value of each component of methane, ethane, propane, butanes and condensates at every receipt and delivery point on the gas transmission system. The cost for component tracking would involve the physical need for improved measurement equipment at most receipt and delivery points, the development of sophisticated tracking software, and the value loss of being forced to sell some NGLs as gas into the local Alberta market. It is assumed that these costs can be accurately estimated, although there is less optimism about whether a methodology for negotiating a fair and equitable allocation system could ever be reached. To highlight the difficulties, some of the obstacles and barriers to reaching agreement are reviewed. In discussing the sources of the problem, it is suggested that if the Alliance Pipeline becomes something other than originally envisioned, something that no longer pose a threat to Nova throughputs or gas richness, discussion of component tracking and balancing will likely slowly slide into oblivion

Instrumental or Physical-Exercise Rehabilitation of Balance Improves Both Balance and Gait in Parkinson’s Disease

Directory of Open Access Journals (Sweden)

Marica Giardini

2018-01-01

Full Text Available We hypothesised that rehabilitation specifically addressing balance in Parkinson’s disease patients might improve not only balance but locomotion as well. Two balance-training protocols (standing on a moving platform and traditional balance exercises were assessed by assigning patients to two groups (Platform, n=15, and Exercises, n=17. The platform moved periodically in the anteroposterior, laterolateral, and oblique direction, with and without vision in different trials. Balance exercises were based on the Otago Exercise Program. Both platform and exercise sessions were administered from easy to difficult. Outcome measures were (a balancing behaviour, assessed by both Index of Stability (IS on platform and Mini-BESTest, and (b gait, assessed by both baropodometry and Timed Up and Go (TUG test. Falls Efficacy Scale-International (FES-I and Parkinson’s Disease Questionnaire (PDQ-8 were administered. Both groups exhibited better balance control, as assessed both by IS and by Mini-BESTest. Gait speed at baropodometry also improved in both groups, while TUG was less sensitive to improvement. Scores of FES-I and PDQ-8 showed a marginal improvement. A four-week treatment featuring no gait training but focused on challenging balance tasks produces considerable gait enhancement in mildly to moderately affected patients. Walking problems in PD depend on postural instability and are successfully relieved by appropriate balance rehabilitation. This trial is registered with ClinicalTrials.gov NCT03314597.

Energy balance and greenhouse gas emissions of dryland camelina as influenced by tillage and nitrogen

International Nuclear Information System (INIS)

Keshavarz-Afshar, Reza; Mohammed, Yesuf Assen; Chen, Chengci

2015-01-01

Despite the great potential of camelina (Camelina sativa L. Crantz) as a promising biofuel feedstock, in-farm energy flow of the crop and its associated environmental impacts has not received sufficient attention from researchers. In order to assess net energy gain and to identify energy saving and environmental friendly production operations, a two year study was conducted at central Montana. We investigated the effects of tillage method (CT (conventional tillage) vs. NT (no-tillage)) and N (nitrogen) fertilizer rate (0, 45, 90 kg N ha −1 ) on energy balance and GHG (greenhouse gas emission) of dryland camelina production. Results indicated that energy input and GHG emission were 5 and 8% lower in NT than in CT. Application of 45 and 90 kg N ha −1 increased camelina energy input by 186 and 365%, while increased energy output by only 21 and 64%, respectively. There was no significant difference in net energy gain in response to N fertilization, but lower energy efficiency in response to higher N inputs. Averaged across tillage systems, the GHG emission was 32.0 kg C eq ha −1 with 0 N applied, and the GHG emission increased by 206 and 389% when 45 and 90 kg N ha −1 was applied. Overall, N fertilizer had the biggest share in total energy input. Averaged over all experimental treatments, 14,945 MJ ha −1 net energy was obtained from camelina crop in this study which shows the potential of this crop as a bioenergy feedstock. Our result showed that implementation of NT is strongly recommendable for camelina production in this region. Moreover, improvement of N use efficiency has the highest priority to improve energy performance and reduce GHG emissions in camelina production. - Highlights: • Camelina produced 14,945 MJ ha −1 of net energy in this study. • No tillage operation reduced 5% energy input and 8% greenhouse gas emission. • Nitrogen fertilizer was the most energy-intensive input in camelina production.

Natural gas and the environment

International Nuclear Information System (INIS)

DeCarufel, A.

1991-01-01

The role of various atmospheric pollutants in environmental changes and the global water cycle, carbon cycle, and energy balance is explained. The role of sulfur dioxide and nitrogen oxides in acid deposition is also outlined. The pollutants that contribute to environmental problems include nitrogen oxides and volatile organic compounds, carbon dioxide, and other greenhouse gases. The potential for natural gas utilization to mitigate some of these pollution problems is explored. Natural gas combustion emits less carbon dioxide and nitrogen oxides than combustion of other fossil fuel, and also does not produce sulfur dioxide, particulates, or volatile organics. Other pollution controlling opportunities offered by natural gas include the use of low-polluting burners, natural gas vehicles, and cogeneration systems. 18 figs., 4 tabs

The dose-response relationship of balance training in physically active older adults.

Science.gov (United States)

Maughan, Kristen K; Lowry, Kristin A; Franke, Warren D; Smiley-Oyen, Ann L

2012-10-01

A 6-wk group balance-training program was conducted with physically active older adults (based on American College of Sports Medicine requirements) to investigate the effect of dose-related static and dynamic balance-specific training. All participants, age 60-87 yr, continued their regular exercise program while adding balance training in 1 of 3 doses: three 20-min sessions/wk (n = 20), one 20-min session/wk (n = 21), or no balance training (n = 19). Static balance (single-leg-stance, tandem), dynamic balance (alternate stepping, limits of stability), and balance confidence (ABC) were assessed pre- and posttraining. Significant interactions were observed for time in single-leg stance, excursion in limits of stability, and balance confidence, with the greatest increase observed in the group that completed 3 training sessions/wk. The results demonstrate a dose-response relationship indicating that those who are already physically active can improve balance performance with the addition of balance-specific training.

Pan-viral specificity of IFN-induced genes reveals new roles for cGAS in innate immunity

Science.gov (United States)

Schoggins, John W.; MacDuff, Donna A.; Imanaka, Naoko; Gainey, Maria D.; Shrestha, Bimmi; Eitson, Jennifer L.; Mar, Katrina B.; Richardson, R. Blake; Ratushny, Alexander V.; Litvak, Vladimir; Dabelic, Rea; Manicassamy, Balaji; Aitchison, John D.; Aderem, Alan; Elliott, Richard M.; García-Sastre, Adolfo; Racaniello, Vincent; Snijder, Eric J.; Yokoyama, Wayne M.; Diamond, Michael S.; Virgin, Herbert W.; Rice, Charles M.

2014-01-01

The type I interferon (IFN) response protects cells from viral infection by inducing hundreds of interferon-stimulated genes (ISGs), some of which encode direct antiviral effectors. Recent screening studies have begun to catalogue ISGs with antiviral activity against several RNA and DNA viruses. However, antiviral ISG specificity across multiple distinct classes of viruses remains largely unexplored. Here we used an ectopic expression assay to screen a library of more than 350 human ISGs for effects on 14 viruses representing 7 families and 11 genera. We show that 47 genes inhibit one or more viruses, and 25 genes enhance virus infectivity. Comparative analysis reveals that the screened ISGs target positive-sense single-stranded RNA viruses more effectively than negative-sense single-stranded RNA viruses. Gene clustering highlights the cytosolic DNA sensor cyclic GMP-AMP synthase (cGAS, also known as MB21D1) as a gene whose expression also broadly inhibits several RNA viruses. In vitro, lentiviral delivery of enzymatically active cGAS triggers a STING-dependent, IRF3-mediated antiviral program that functions independently of canonical IFN/STAT1 signalling. In vivo, genetic ablation of murine cGAS reveals its requirement in the antiviral response to two DNA viruses, and an unappreciated contribution to the innate control of an RNA virus. These studies uncover new paradigms for the preferential specificity of IFN-mediated antiviral pathways spanning several virus families.

Mass balance of the Amitsulôq ice cap, West Greenland

DEFF Research Database (Denmark)

Ahlstrøm, Andreas P.; Bøggild, Carl Egede; Olesen, Ole B.

2007-01-01

We present detailed mass balance measurements from the Amitsulôq ice cap in West Greenland spanning from 1982 to 1990. The data includes summer and winter balances from 26 stake locations distributed over five transects covering the whole ice cap. The mass balance measurements are combined...... with a recent satellite-derived digital elevation model to calculate the specific balance, which is in turn compared to discharge data from the adjacent Tasersiaq basin. The correlation between specific summer balance and discharge is R2 = 0.93 indicating that the basin discharge is dominated by glacial...... meltwater, linking the hydropower potential of the basin closely to the fate of the adjoining Greenland ice-sheet margin....

Improvement of gas entrainment prediction method. Introduction of surface tension effect

International Nuclear Information System (INIS)

Ito, Kei; Sakai, Takaaki; Ohshima, Hiroyuki; Uchibori, Akihiro; Eguchi, Yuzuru; Monji, Hideaki; Xu, Yongze

2010-01-01

A gas entrainment (GE) prediction method has been developed to establish design criteria for the large-scale sodium-cooled fast reactor (JSFR) systems. The prototype of the GE prediction method was already confirmed to give reasonable gas core lengths by simple calculation procedures. However, for simplification, the surface tension effects were neglected. In this paper, the evaluation accuracy of gas core lengths is improved by introducing the surface tension effects into the prototype GE prediction method. First, the mechanical balance between gravitational, centrifugal, and surface tension forces is considered. Then, the shape of a gas core tip is approximated by a quadratic function. Finally, using the approximated gas core shape, the authors determine the gas core length satisfying the mechanical balance. This improved GE prediction method is validated by analyzing the gas core lengths observed in simple experiments. Results show that the analytical gas core lengths calculated by the improved GE prediction method become shorter in comparison to the prototype GE prediction method, and are in good agreement with the experimental data. In addition, the experimental data under different temperature and surfactant concentration conditions are reproduced by the improved GE prediction method. (author)

Energy efficiency and the influence of gas burners to the energy related carbon dioxide emissions of electric arc furnaces in steel industry

International Nuclear Information System (INIS)

Kirschen, Marcus; Risonarta, Victor; Pfeifer, Herbert

2009-01-01

Determining the complete energy balance of an electric arc furnace (EAF) provides an appropriate method to examine energy efficiency and identify energy saving potentials. However, the EAF energy balance is complex due to the combined input of electrical energy and chemical energy resulting from natural gas (NG) combustion and oxidation reactions in the steel melt. In addition, furnace off-gas measurements and slag analysis are necessary to reliably determine energy sinks. In this paper 70 energy balances and energy efficiencies from multiple EAFs are presented, including data calculated from plant measurements and compiled from the literature. Potential errors that can be incorporated in these calculations are also highlighted. The total energy requirement of these modern EAFs analysed ranged from 510 to 880 kWh/t, with energy efficiency values (η = ΔH Steel /E Total ) of between 40% and 75%. Furthermore, the focus was placed on the total energy related CO 2 emissions of EAF processes comprising NG combustion and electrical energy input. By assessing multiple EAF energy balances, a significant correlation between the total energy requirement and energy related specific CO 2 emissions was not evident. Whilst the specific consumption of NG in the EAF only had a minor impact on the EAF energy efficiency, it decreased the specific electrical energy requirement and increased EAF productivity where transformer power was restricted. The analysis also demonstrated that complementing and substituting electrical energy with NG was beneficial in reducing the total energy related CO 2 emissions when a certain level of substitution efficiency was achieved. Therefore, the appropriate use of NG burners in modern EAFs can result in an increased EAF energy intensity, whilst the total energy related CO 2 emissions remain constant or are even decreased.

Implications of multiplane-multispeed balancing for future turbine engine design and cost

Science.gov (United States)

Badgley, R. H.

1974-01-01

This paper describes several alternative approaches, provided by multiplane-multispeed balancing, to traditional gas turbine engine manufacture and assembly procedures. These alternatives, which range from addition of trim-balancing at the end of the traditional assembly process to modular design of the rotating system for assembly and balancing external to the engine, require attention by the engine designer as an integral part of the design process. Since multiplane-multispeed balancing may be incorporated at one or more of several points during manufacture-assembly, its deliberate use is expected to provide significant cost and performance (reduced vibration) benefits. Moreover, its availability provides the designer with a firm base from which he may advance, with reasonable assurance of success, into the flexible rotor dynamic regime.

Development and linearization of generalized material balance equation for coal bed methane reservoirs

International Nuclear Information System (INIS)

Penuela, G; Ordonez R, A; Bejarano, A

1998-01-01

A generalized material balance equation was presented at the Escuela de Petroleos de la Universidad Industrial de Santander for coal seam gas reservoirs based on Walsh's method, who worked in an analogous approach for oil and gas conventional reservoirs (Walsh, 1995). Our equation was based on twelve similar assumptions itemized by Walsh for his generalized expression for conventional reservoirs it was started from the same volume balance consideration and was finally reorganized like Walsh (1994) did. Because it is not expressed in terms of traditional (P/Z) plots, as proposed by King (1990), it allows to perform a lot of quantitative and qualitative analyses. It was also demonstrated that the existent equations are only particular cases of the generalized expression evaluated under certain restrictions. This equation is applicable to coal seam gas reservoirs in saturated, equilibrium and under saturated conditions, and to any type of coal beds without restriction on especial values of the constant diffusion

A simulation-based approach for solving assembly line balancing problem

Science.gov (United States)

Wu, Xiaoyu

2017-09-01

Assembly line balancing problem is directly related to the production efficiency, since the last century, the problem of assembly line balancing was discussed and still a lot of people are studying on this topic. In this paper, the problem of assembly line is studied by establishing the mathematical model and simulation. Firstly, the model of determing the smallest production beat under certain work station number is anysized. Based on this model, the exponential smoothing approach is applied to improve the the algorithm efficiency. After the above basic work, the gas stirling engine assembly line balancing problem is discussed as a case study. Both two algorithms are implemented using the Lingo programming environment and the simulation results demonstrate the validity of the new methods.

Does an exercise programme integrating the Nintendo Wii-Fit Balance Board improve balance in ambulatory children with cerebral palsy?

OpenAIRE

Cooper, T.; Williams, Jonathan M.

2017-01-01

Background: Cerebral palsy is a common childhood movement disorder with balance impairment a common complaint. Active video games such as the Nintendo Wii-Fit have been found to be a valuable therapeutic tool, enjoyed by a variety of populations including children with CP, but a synthesis of the research investigating its specific use for balance in children with CP has yet to be conducted.\\ud \\ud Objectives: To determine the effectiveness of a Nintendo Wii-Fit Balance board programme in impr...

Parameterization of Leaf-Level Gas Exchange for Plant Functional Groups From Amazonian Seasonal Tropical Rain Forest

Science.gov (United States)

Domingues, T. F.; Berry, J. A.; Ometto, J. P.; Martinelli, L. A.; Ehleringer, J. R.

2004-12-01

Plant communities exert strong influence over the magnitude of carbon and water cycling through ecosystems by controlling photosynthetic gas exchange and respiratory processes. Leaf-level gas exchange fluxes result from a combination of physiological properties, such as carboxylation capacity, respiration rates and hydraulic conductivity, interacting with environmental drivers such as water and light availability, leaf-to-air vapor pressure deficit, and temperature. Carbon balance models concerned with ecosystem-scale responses have as a common feature the description of eco-physiological properties of vegetation. Here we focus on the parameterization of ecophysiological gas-exchange properties of plant functional groups from a pristine Amazonian seasonally dry tropical rain forest ecosystem (FLONA-Tapajós, Santarém, PA, Brazil). The parameters were specific leaf weight, leaf nitrogen content, leaf carbon isotope ratio, maximum photosynthetic assimilation rate, photosynthetic carboxylation capacity, dark respiration rates, and stomatal conductance to water vapor. Our plant functional groupings were lianas at the top of the canopy, trees at the top of the canopy, mid-canopy trees and undestory trees. Within the functional groups, we found no evidence that leaves acclimated to seasonal changes in precipitation. However, there were life-form dependent distinctions when a combination of parameters was included. Top-canopy lianas were statistically different from top-canopy trees for leaf carbon isotope ratio, maximum photosynthetic assimilation rate, and stomatal conductance to water vapor, suggesting that lianas are more conservative in the use of water, causing a stomatal limitation on photosynthetic assimilation. Top-canopy, mid canopy and understory groupings were distinct for specific leaf weight, leaf nitrogen content, leaf carbon isotope ratio, maximum photosynthetic assimilation rate, and photosynthetic carboxylation capacity. The recognition that plant

Balance perturbation system to improve balance compensatory responses during walking in old persons

Directory of Open Access Journals (Sweden)

Melzer Itshak

2010-07-01

Full Text Available Abstract Ageing commonly disrupts the balance control and compensatory postural responses that contribute to maintaining balance and preventing falls during perturbation of posture. This can lead to increased risk of falling in old adults (65 years old and over. Therefore, improving compensatory postural responses during walking is one of the goals in fall prevention programs. Training is often used to achieve this goal. Most fall prevention programs are usually directed towards improving voluntary postural control. Since compensatory postural responses triggered by a slip or a trip are not under direct volitional control these exercises are less expected to improve compensatory postural responses due to lack of training specificity. Thus, there is a need to investigate the use balance perturbations during walking to train more effectively compensatory postural reactions during walking. This paper describes the Balance Measure & Perturbation System (BaMPer System a system that provides small, controlled and unpredictable perturbations during treadmill walking providing valuable perturbation, which allows training compensatory postural responses during walking which thus hypothesize to improve compensatory postural responses in older adults.

Trends in the development of the use of natural gas in Latvia in the EU context

International Nuclear Information System (INIS)

Davis, A.; Gedrovics, M.; Ekmanis, J.; Zeltins, N.

2004-01-01

The work reflect the growing share of natural gas among various types of fuel used in the EU, which has taken place during the recent decade as a result of technological progress, better understanding of the environmental issues in the European Union as well as lower prices in comparison with those of the liquid fuel. The Latvian fuel balance of the recent years indicates that the prevailing energy resources are natural gas, oil products and firewood. The paper gives comparison of the share of natural gas in the balance of energy consumption in the EU and the future member states as well as a comparison of the energy balance in Latvia and the EU-15. (authors)

The Integration of Gasification Systems with Gas Engine by Developing Wet Tar Scrubbers and Gas Filter to Produce Electrical Energy from Biomass

Directory of Open Access Journals (Sweden)

Siregar Kiman

2018-01-01

Full Text Available The need for energy especially biomass-based renewable energy continues to increase in Indonesia. The objective of this research was to design downdraft gasifier machine with high content of combustible gas on gas engine. Downdraft gasifier machine was adjusted with the synthetic gas produced from biomass. Besides that, the net energy ratio, net energy balance, renewable index, economic analysis and impact assessment also been conducted. Gas engine that was designed in this research had been installed with capacity of 25 kW with diameter and height of reactorwere 900 mm and 1 000 mm respectively. The method used here werethe design the Detailed Engineering Design, assembly, and performance test of gas engine. The result showed that gas engine for biomass can be operated for 8 h with performance engine of 84 % and capacity of 25 kW. Net energy balance, net energy ratio, and renewable index was 30 MJ/kW h electric; 0.89; 0.76 respectively. The value of GHG emission of Biomass Power Generation is 0.03 kg-CO2 eq per MJ. Electrical production cost for Biomass Power Generation is about IDR 1 500 per kW h which is cheaper than solar power generation which is about of IDR 3 300 per kW h.

Reliability and validity of the German short version of the Activities specific Balance Confidence (ABC-D6) scale in older adults.

Science.gov (United States)

Schott, Nadja

2014-01-01

The Activities specific Balance Confidence (ABC) is a questionnaire which was developed to assess falls-associated self-efficacy. The aim of this study was to evaluate reliability and validity of the German abbreviated 6-item version of the ABC scores in community-dwelling older people. The study sample included 384 subjects (age 71.1 ± 9.7). In order to determine the psychometric properties, reliability and validity were assessed through administration of the German adaptation of the ABC-D16 to participants twice, 10 days apart, and comparison of the ABC-D16 and the ABC-D6 with functional measures of balance and mobility (one-leg stance; 10 m walk; TUG; Fullerton Advanced Balance Scale (FAB)), physical activity (Physical Activity Scale for the Elderly (PASE)), physical fitness (30s arm curl, 30s chair stand, 6 min walk), cognition (Trail-Making-Test (TMT)), falls status, and quality of life (SF36). Factor analyses suggested a 1-factor solution for the ABC-D6 scale (explained variance 79.8%). Internal consistency (.95) and test-retest reliability (.98) for the ABC-D6 scores were excellent. Scores on the ABC-D6 were significantly lower than on the ABC-D16, but ABC-D16 and ABC-D6 scores were highly correlated (.94). There was an increasing difference in the ABC-scores between men and women with increasing age. Fallers reported lower balance confidence than non-fallers. The ABC-D6 score significantly correlated with functional measures of balance and mobility, physical activity, physical fitness, cognition, and quality of life (-.698valid instrument to asses falls-associated self-efficacy and may be used in future research projects and clinical trials. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

The oil and gas industry and the Canadian economy: a backgrounder

International Nuclear Information System (INIS)

1999-06-01

The technological and economic significance of the Canadian petroleum industry to the national economy and to Canada's standing in the world are reviewed. The six key ways in which the oil and gas industry affects Canada, namely employment, balance of trade, products, government revenues, international technology trade and community support are stressed within the context of describing present and future oil and gas resources, Canada's petroleum and natural gas trade balance, and capital spending and product sales. Attention is also drawn to the role of the Canadian petroleum and natural gas industry as a producer and exporter of world class technology, especially in the areas of high tech exploration methods, cold-climate and offshore operations, enhanced recovery techniques, heavy oil production and and processing, mining and upgrading of oil sands bitumen, oil well firefighting, and environmental protection technology. maps, figs

Natural gas measurement process development in PETROBRAS system: new concepts and challenges; Desenvolvimento do processo de medicao de gas natural no sistema PETROBRAS: novos conceitos e desafios

Energy Technology Data Exchange (ETDEWEB)

Correa, Carlos Alexandre L. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Mercon, Eduardo G. [PETROBRAS Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

2005-07-01

Considering the wide increase of natural gas participation in the Brazilian energetic source matrix, this paper describes, comments and analyzes how the natural gas flow measurement process has been structured in PETROBRAS, so that it become a potential factor of this increase. Initially, the work makes a metrological approach of measured volumes, based on volumetric balance of the gas flow in the two principals pipe segments of PETROBRAS gas line network, localized in the Brazilian southeast and northeast systems. This approach runs through the investigation of several parameters that have influence on that balance, considering field installation improvement and normative adjustments, sketching aims and suggesting best practices for its optimization. Further, it will be described PETROBRAS' systems being in use to provide natural gas flow measurement control and management, from available data in transporters' SCADA system to billing, and to integrate the processes of: shipping scheduling; transmission and delivering; real time supervision; and consolidation of these information for invoicing. (author)

Natural gas measurement process development in PETROBRAS system: new concepts and challenges; Desenvolvimento do processo de medicao de gas natural no sistema PETROBRAS: novos conceitos e desafios

Energy Technology Data Exchange (ETDEWEB)

Correa, Carlos Alexandre L [PETROBRAS, Rio de Janeiro, RJ (Brazil); Mercon, Eduardo G [PETROBRAS Transporte S.A. (TRANSPETRO), Rio de Janeiro, RJ (Brazil)

2005-07-01

Considering the wide increase of natural gas participation in the Brazilian energetic source matrix, this paper describes, comments and analyzes how the natural gas flow measurement process has been structured in PETROBRAS, so that it become a potential factor of this increase. Initially, the work makes a metrological approach of measured volumes, based on volumetric balance of the gas flow in the two principals pipe segments of PETROBRAS gas line network, localized in the Brazilian southeast and northeast systems. This approach runs through the investigation of several parameters that have influence on that balance, considering field installation improvement and normative adjustments, sketching aims and suggesting best practices for its optimization. Further, it will be described PETROBRAS' systems being in use to provide natural gas flow measurement control and management, from available data in transporters' SCADA system to billing, and to integrate the processes of: shipping scheduling; transmission and delivering; real time supervision; and consolidation of these information for invoicing. (author)

Natural gas industry in Bulgaria

International Nuclear Information System (INIS)

Mashkin, L.

1994-01-01

An overview of the Bulgarian natural gas industry is presented. The starting point was the discovery of the indigenous Chiren gas-field in 1967. The first agreement with the ex-USSR for supply of natural gas and construction of main pipelines was signed in 1968. The state gas company BULGARGAZ is responsible for transportation, storage, distribution, processing and marketing of the gas to over 150 industrial companies in the country, as well as for the transportation services to gas importers in neighboring Turkey. The GAZSTROJMONTAZH company accomplish the construction of the local and transit pipelines to Turkey and Greece, as well as of some objects in Iran, Syria, Ukraine and Germany. In the past 20 years, 87890 million m 3 natural gas from Russia are supplied and 846 million m 3 - from domestic sources. The share of natural gas in the overall energy balance is 13.6% for 1992. The restructuring and further development of gas industry require to take into account some factors as: security in supply; investments for technical assurance; pricing policy for natural gas; development of private business. Some administrative problems are also mentioned. 2 tabs., 1 fig

1970-1997 energy balance-sheets

International Nuclear Information System (INIS)

1998-01-01

The aim of this document is to bring together a consistent and harmonized set of statistical data on energy economics in the French territory. The information is based on the global and structural approach of the different energy balance-sheets published between 1970 and 1997. The first chapter gives a general idea of the energy situation of the passed year and outlines the evolution of the main aggregates (production, primary and final consumption etc..) comparatively to those of the general economy. The second chapter is devoted to the history of energy economics. Time series of indicators and diagrams allow to precise the structural modifications that occurred during the last decades. The main transformations in the national energy production and the development of the different energy sources in the industry, the residential and tertiary sectors and in the transportation sector are described too. The third chapter gives numerical data on energy for the last 28 years using the common Mtpe unit (million of tons of petroleum equivalent). These balance sheets are based on new energy keeping methods and use identical equivalence coefficients. The last chapter presents the energy balance sheets for the last three years, using the proper units for coal, petroleum, gas and electricity. (J.S.)

The effect of a supervised community-based exercise program on balance, balance confidence, and gait in individuals with lower limb amputation.

Science.gov (United States)

Miller, Carol A; Williams, Jennifer E; Durham, Katey L; Hom, Selena C; Smith, Julie L

2017-10-01

Many individuals with lower limb loss report concern with walking ability after completing structured traditional rehabilitation. The purpose of this study was to explore the impact of a supervised community-based exercise program on balance, balance confidence, and gait in individuals with lower limb amputation. Repeated measures. The supervised exercise program was offered biweekly for 6 weeks. The GAITRite System by CIR Systems, Inc., the Figure-of-8 Walk Test, and Activity-specific Balance Confidence Scale were used to measure clinical outcomes pre- and post-intervention. In total, 16 participants with lower limb amputation (mean age: 50.8 years) completed the study. A multivariate, repeated measures analysis of variance indicated a statistically significant effect of training across six clinical outcome measures ( F(6, 10) = 4.514, p = .018). Moderate effect sizes were found for the Figure-of-8 Walk Test ( η 2 = .586), Activity-specific Balance Confidence Scale ( η 2 = .504), and gait velocity at comfortable walking speed ( η 2 = .574). The average increase in gait speed was clinically meaningful at .14 m/s. The supervised community-based exercise program implemented in this study was designed to address specific functional needs for individuals with lower limb loss. Each participant experienced clinically meaningful improvements in balance, balance confidence, and walking ability. Clinical relevance The provision of a supervised community-based exercise program, after traditional rehabilitation, provides opportunity to offer a continuum of care that may enhance prosthetic functional ability and active participation in the community for individuals with lower limb amputation.

European Union gas market liberalization: a windfall effect for Russia?

International Nuclear Information System (INIS)

Riviere, Nicolas

2013-01-01

Natural gas has a growing importance in the European Union energy. However, because of the lack of resources in its territory, the EU is highly dependent on imports to meet its gas needs. In parallel, since 1998 the EU seeks the creation of a single and liberalized natural gas market. The aim of this thesis is to investigate whether the gas market liberalization can create a risk for importers' bargaining power and more widely to the gas security of supply of the EU. The first chapter provides an overview of the European gas market. It deals with the implementation of the process of gas market liberalization, the external dependency of the EU and the weakness of gas supply diversity. Using findings from the previous chapter, the second one proposes a model from the cooperative game theory to analyze the effects of the EU natural gas market liberalization on importers' bargaining power. It shows that the liberalization weakens importers' bargaining power vis-a-vis external suppliers, where Russia is the leader. It also shows that the implementation of a European gas purchasing agency offers a counter-power to the EU that balances bargaining power. The third chapter focuses on the development of LNG in the world and more specifically in the EU market. The development of LNG in Europe allows the entry of new operators on the upstream and, thus, increases competition among the EU's suppliers for the benefit of importers' bargaining power. The last chapter analyzes the impact of US shale gas development on the EU gas market. Thus, it shows that development is accompanied by an uncertainty about the future gas demand in the EU and by a reconsideration of the EU's long-term contracts. (author)

Greenhouse gas and energy analysis of substitute natural gas from biomass for space heat

Energy Technology Data Exchange (ETDEWEB)

Pucker, J.; Jungmeier, G. [JOANNEUM RESEARCH Forschungsgesellschaft mbH, RESOURCES - Institute for Water, Energy and Sustainability, Steyrergasse 17, 8010 Graz (Austria); Zwart, R. [Energy Research Centre of The Netherlands (ECN), Westerduinweg 3, 1755 LE Petten (Netherlands)

2012-03-15

In this paper, the greenhouse gas and energy balances of the production and use for space heating of substitute natural gas from biomass (bio-SNG) for space heat are analysed. These balances are compared to the use of natural gas and solid biomass as wood chips to provide the same service. The reduction of the greenhouse gas emissions (CO{sub 2}-eq.) - carbon dioxide, methane and nitrous oxide - and of the fossil primary energy use is investigated in a life cycle assessment (LCA). This assessment was performed for nine systems for bio-SNG; three types of gasification technologies (O{sub 2}-blown entrained flow, O{sub 2}-blown circulating fluidised bed and air-steam indirect gasification) with three different types of feedstock (forest residues, miscanthus and short rotation forestry). The greenhouse gas analysis shows that forest residues using the air-steam indirect gasification technology result in the lowest greenhouse gas emissions (in CO{sub 2}-eq. 32 kg MWh{sup -1} of heat output). This combination results in 80% reduction of greenhouse gas emissions when compared to natural gas and a 29% reduction of greenhouse gases if the forest residues were converted to wood chips and combusted. The gasification technologies O{sub 2}-blown entrained flow and O{sub 2}-blown circulating fluidised bed gasification have higher greenhouse gas emissions that range between in CO{sub 2}-eq. 41 to 75 kg MWh{sup -1} of heat output depending on the feedstock. When comparing feedstocks in the bio-SNG systems, miscanthus had the highest greenhouse gas emissions bio-SNG systems producing in CO2-eq. 57-75 kg MWh{sup -1} of heat output. Energy analysis shows that the total primary energy use is higher for bio-SNG systems (1.59-2.13 MWh MWh{sup -1} of heat output) than for the reference systems (in 1.37-1.51 MWh MWh{sup -1} of heat output). However, with bio-SNG the fossil primary energy consumption is reduced compared to natural gas. For example, fossil primary energy use is reduced by

Analysis of energy and greenhouse gas balance as indexes for environmental assessment of wheat and maize farming: a case study

Directory of Open Access Journals (Sweden)

Móslem SAMI

2015-12-01

Full Text Available In this study, the net balance of greenhouse gas (GHG emission and energy of wheat and maize production systems in two farms in Khuzestan province of Iran was assessed. The results showed that totally wheat farming is more efficient than maize farming in terms of energy and CO2-eq indexes. The total energy requirement for maize and wheat farming was 92560.24 MJ ha-1 and 39624.15 MJ ha-1, which caused the emission of 20191.47 and 7541.04 kg CO2-equivalent per hectare in maize and wheat farms respectively. Electricity, fertilizers and fuel were the most important pollutants of environment in terms of energy and gas emission in both farms. Theses inputs consumed 55.52, 22.62 and 6.44 % of total energy of maize and 47.32, 21.19 and 9.01 % of total energy of wheat farm and were responsible for the 88.60, 8.79 and 2.03 % of CO2-equivalent in maize and 86.54, 9.54 and 3.24 % of CO2-equivalent in wheat farms respectively. The results of this study also showed that the enhancement of 60.74 and 27.02 % in energy ratio and 46.06 and 27.87 % in CO2-eq index in maize and wheat farming can be expected using simple improving scenarios.

Energy statistics and balances of non-OECD countries 1991-1992

International Nuclear Information System (INIS)

1994-01-01

Contains a compilation of energy production and consumption statistics for 85 non-OECD countries and regions, including developing countries, Central and Eastern European countries and the former Soviet Union. Data are expressed in original units and in common units for coal, oil, gas, electricity and heat. Historical tables for both individual countries and regions summarize data on coal, gas and electricity production and consumption since 1971. Similar data for OECD are available in the IEA publications Energy Statistics and Energy Balances of OECD Countries

Quality Assurance Project Plan for the Gas Generation Testing Program at the INEL

International Nuclear Information System (INIS)

1994-10-01

The data quality objectives (DQOs) for the Program are to evaluate compliance with the limits on total gas generation rates, establish the concentrations of hydrogen and methane in the total gas flow, determine the headspace concentration of VOCs in each drum prior to the start of the test, and obtain estimates of the concentrations of several compounds for mass balance purposes. Criteria for the selection of waste containers at the INEL and the parameters that must be characterized prior to and during the tests are described. Collection of gaseous samples from 55-gallon drums of contact-handled transuranic waste for the gas generation testing is discussed. Analytical methods and calibrations are summarized. Administrative quality control measures described in this QAPjP include the generation, review, and approval of project documentation; control and retention of records; measures to ensure that personnel, subcontractors or vendors, and equipment meet the specifications necessary to achieve the required data quality for the project

Comparison of energy and greenhouse gas balances of biogas with other transport biofuel options based on domestic agricultural biomass in Finland

Directory of Open Access Journals (Sweden)

H. L. TUOMISTO

2008-12-01

Full Text Available Biofuels have been promoted as a way to reduce greenhouse gas (GHG emissions, but it is questionable whether they indeed do so. The study compared energy and GHG balances of transport biofuels produced in Finnish conditions. Energy and GHG balances were calculated from a life cycle perspective for biogas when timothy-clover and reed canary grass silages and green manure of an organic farm were used as a raw material. The results were compared with published data on barley-based ethanol, rape methyl ester (biodiesel and biowaste-based biogas. The energy input for biogas was 22–37% of the output depending on the raw material. The GHG emissions from field-based biogas were 21–36% of emissions from fossil-based fuels. The largest energy input was used in the processing of the biofuels while most of the greenhouse gases were emitted during farming. The GHG emissions of the field-based biogas were emitted mainly from fuels of farming machinery, nitrous oxide (N2O emissions of the soil and the production of ensiling additives. The energy efficiency was most sensitive to the methane yield, and GHG emissions to the N2O emissions. Biogas had clearly lower energy input and GHG emissions per unit energy output than domestic barley-based ethanol and biodiesel.;

Sustaining the balance : maintaining the basin's competitive edge

International Nuclear Information System (INIS)

Carruthers, J.

1998-01-01

Competition has been described as the driving force in today's natural gas industry. The issue of how to strengthen the competitive edge of the Western Canadian Sedimentary Basin in the North American marketplace was discussed. The principal suggestion that emerged was that keeping transportation capacity and production capability in balance was crucial as such efforts would provide benefits for pipelines, shippers, consumers and producers. Suggestions on how to achieve and sustain the balance between transportation and production capacity were offered. Creating awareness of who the true competitors are, meeting their challenge, and changing the regulatory system to provide incentives for pipelines to build and to provide greater customer choice and service flexibility, were some of the suggestions discussed

Natural gas market assessment: Long-term Canadian natural gas contracts

International Nuclear Information System (INIS)

1992-08-01

A descriptive analysis is presented of the changes which have occurred and the developing trends in the long-term Canadian contracts governing the sale of western Canadian gas into the domestic and export markets from 1985 to 1991. The report is limited to domestic and export contracts for Canadian gas and does not include imported gas under contract. Contract structures prior to deregulation, the changing role of long-term contracts, size and duration of long-term contracts, and terms and conditions of long-term contracts are discussed. Important changes since the mid-1980s include: increased flexibility in long-term contracts enabling the parties to respond more readily to changing supply and demand conditions; greater balance between the buyer's obligation to purchase and the seller's obligation to deliver; flexible and increasingly simple pricing terms that track competitive market conditions; shorter contract terms; reduced contract volumes as smaller end-users and producer/marketers enter the market; and unbundling of gas sales and transportation service providing a wider range of contracting choices and options. 36 figs., 2 tabs

Using Noble Gas Measurements to Derive Air-Sea Process Information and Predict Physical Gas Saturations

Science.gov (United States)

Hamme, Roberta C.; Emerson, Steven R.; Severinghaus, Jeffrey P.; Long, Matthew C.; Yashayaev, Igor

2017-10-01

Dissolved gas distributions are important because they influence oceanic habitats and Earth's climate, yet competing controls by biology and physics make gas distributions challenging to predict. Bubble-mediated gas exchange, temperature change, and varying atmospheric pressure all push gases away from equilibrium. Here we use new noble gas measurements from the Labrador Sea to demonstrate a technique to quantify physical processes. Our analysis shows that water-mass formation can be represented by a quasi steady state in which bubble fluxes and cooling push gases away from equilibrium balanced by diffusive gas exchange forcing gases toward equilibrium. We quantify the rates of these physical processes from our measurements, allowing direct comparison to gas exchange parameterizations, and predict the physically driven saturation of other gases. This technique produces predictions that reasonably match N2/Ar observations and demonstrates that physical processes should force SF6 to be ˜6% more supersaturated than CFC-11 and CFC-12, impacting ventilation age calculations.

Evaluating Work-Life Balance in the Department of Defense

Science.gov (United States)

2011-04-18

Evaluating Work - Life Balance in the Department of Defense Erin A. Moeser Defense Equal Opportunity Management Institute (DEOMI) Kizzy M. Parks...for service members’ family lives may increase satisfaction with work - life balance . Examples of family-friendly organizational policies include...1,500 active duty military personnel were surveyed on the value of work / life balance initiates. More specifically, this study assessed respondents

Natural gas - Market and environmental needs

International Nuclear Information System (INIS)

Beyer, R.

1995-01-01

The paper discusses the natural gas market and environmental needs with topics as follow: Importance of the North Sea region; sustainable development on the balance between economic use and environmental protection; role of natural gas in meeting energy demand: market needs, technologies, environmental aspects. According to the author, natural gas causes minimal pollutants because it contains virtually no pollutant-forming substances such as heavy metals, sulphur, chlorine or fluorine. No solid residues exist in the combustion space such as ash, slag, dust or soot, and the formation of thermal NO x through natural gas combustion has decreased to a very large extent as a result of technical advances. Natural gas can make a significant contribution towards reducing CO 2 emissions due to its very high hydrogen content. 12 figs

Simple, specific analysis of organophosphorus and carbamate pesticides in sediments using column extraction and gas chromatography

Science.gov (United States)

Belisle, A.A.; Swineford, D.M.

1988-01-01

A simple, specific procedure was developed for the analysis of organophosphorus and carbamate pesticides in sediment. The wet soil was mixed with anhydrous sodium sulfate to bind water and the residues were column extracted in acetone:methylene chloride (1:l,v/v). Coextracted water was removed by additional sodium sulfate packed below the sample mixture. The eluate was concentrated and analyzed directly by capillary gas chromatography using phosphorus and nitrogen specific detectors. Recoveries averaged 93 % for sediments extracted shortly after spiking, but decreased significantly as the samples aged.

Recharge contribution to the Guarani Aquifer System estimated from the water balance method in a representative watershed.

Science.gov (United States)

Wendland, Edson; Gomes, Luis H; Troeger, Uwe

2015-01-01

The contribution of recharge to regional groundwater flow systems is essential information required to establish sustainable water resources management. The objective of this work was to determine the groundwater outflow in the Ribeirão da Onça Basin using a water balance model of the saturated soil zone. The basin is located in the outcrop region of the Guarani Aquifer System (GAS). The water balance method involved the determination of direct recharge values, groundwater storage variation and base flow. The direct recharge was determined by the water table fluctuation method (WTF). The base flow was calculated by the hydrograph separation method, which was generated by a rain-flow model supported by biweekly streamflow measurements in the control section. Undisturbed soil samples were collected at depths corresponding to the variation zone of the groundwater level to determine the specific yield of the soil (drainable porosity). Water balances were performed in the saturated zone for the hydrological years from February 2004 to January 2007. The direct recharge ranged from 14.0% to 38.0%, and groundwater outflow from 0.4% to 2.4% of the respective rainfall during the same period.

The gas industry in the year 2020

International Nuclear Information System (INIS)

Chabrelie, M.F.

2006-01-01

Having been reserved for decades primarily for the more noble uses of industry, natural gas, which basically has no captive market, is now the energy of choice in a multitude of applications. Although gas resources are limited in the very long term, they are yet sufficiently abundant to make a major contribution to the energy industry of the 21. century. Endowed with intrinsic qualities that make it less pollutant than its competitors, natural gas is the commercial energy harboring the strongest growth potential in the future energy balance. (author)

The gas industry in the year 2020

Energy Technology Data Exchange (ETDEWEB)

Chabrelie, M.F

2006-07-01

Having been reserved for decades primarily for the more noble uses of industry, natural gas, which basically has no captive market, is now the energy of choice in a multitude of applications. Although gas resources are limited in the very long term, they are yet sufficiently abundant to make a major contribution to the energy industry of the 21. century. Endowed with intrinsic qualities that make it less pollutant than its competitors, natural gas is the commercial energy harboring the strongest growth potential in the future energy balance. (author)

Natural Gas Information 2013 with 2012 data

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-01

A detailed reference work on gas supply and demand covering not only the OECD countries but also the rest of the world, this publication contains essential information on LNG and pipeline trade, gas reserves, storage capacity and prices. The main part of the book, however, concentrates on OECD countries, showing a detailed supply and demand balance for each country and for the three OECD regions: Americas, Asia-Oceania and Europe, as well as a breakdown of gas consumption by end-user. Import and export data are reported by source and destination.

Prediction of Balance Compensation After Vestibular Schwannoma Surgery.

Science.gov (United States)

Parietti-Winkler, Cécile; Lion, Alexis; Frère, Julien; Perrin, Philippe P; Beurton, Renaud; Gauchard, Gérome C

2016-06-01

Background Balance compensation after vestibular schwannoma (VS) surgery is under the influence of specific preoperative patient and tumor characteristics. Objective To prospectively identify potential prognostic factors for balance recovery, we compared the respective influence of these preoperative characteristics on balance compensation after VS surgery. Methods In 50 patients scheduled for VS surgical ablation, we measured postural control before surgery (BS), 8 (AS8) days after, and 90 (AS90) days after surgery. Based on factors found previously in the literature, we evaluated age, body mass index and preoperative physical activity (PA), tumor grade, vestibular status, and preference for visual cues to control balance as potential prognostic factors using stepwise multiple regression models. Results An asymmetric vestibular function was the sole significant explanatory factor for impaired balance performance BS, whereas the preoperative PA alone significantly contributed to higher performance at AS8. An evaluation of patients' balance recovery over time showed that PA and vestibular status were the 2 significant predictive factors for short-term postural compensation (BS to AS8), whereas none of these preoperative factors was significantly predictive for medium-term postoperative postural recovery (AS8 to AS90). Conclusions We identified specific preoperative patient and vestibular function characteristics that may predict postoperative balance recovery after VS surgery. Better preoperative characterization of these factors in each patient could inform more personalized presurgical and postsurgical management, leading to a better, more rapid balance recovery, earlier return to normal daily activities and work, improved quality of life, and reduced medical and societal costs. © The Author(s) 2015.

The application of the pore population balance method to the calculation of the radiolytic weight loss and gas transport property changes of nuclear graphites

International Nuclear Information System (INIS)

Johnson, P.A.V.

1982-01-01

A pore population balance equation, previously used to describe the physical property changes of porous carbons during thermal oxidation in carbon dioxide, has been modified to treat the radiolytic oxidation of graphite in CO 2 /CO/CH 4 gas mixtures. Good agreement has been obtained between theory and experiment for the variation in the gas transport coefficients B, K and lambda of gilsonite graphite with absorbed radiation dose. Calculations indicate that the addition of blind pores to the transport porosity, and an allowance for the opening of closed pores with burn-off, do not account for the experimental fractional weight loss curve. An excellent fit is obtained, however, if a small volume of cylindrical pores of a mean radius approximately equal to the diffusion length of oxidising species in the coolant are present in the pore size spectrum. Gilsonite graphite therefore behaves as if the pore size distribution function is trimodal, with mean radii at about 0.5μm, 2.48μm and greater than or equal to 10.57μm. (author)

Immunomodulation Mechanism of Antidepressants: Interactions between Serotonin/Norepinephrine Balance and Th1/Th2 Balance

Science.gov (United States)

Martino, Matteo; Rocchi, Giulio; Escelsior, Andrea; Fornaro, Michele

2012-01-01

Neurotransmitters and hormones regulate major immune functions, including the selection of T helper (Th)1 or Th2 cytokine responses, related to cell-mediated and humoral immunity, respectively. A role of imbalance and dynamic switching of Th1/Th2 system has been proposed, with relative displacement of the immune reserve in relation to complex interaction between Th1/Th2 and neuro-hormonal balance fluctuations, in the pathogenesis of various chronic human diseases, probably also including psychiatric disorders. Components of the stress system such as norepinephrine (NE) and glucocorticoids appear to mediate a Th2 shift, while serotonin (5-HT) and melatonin might mediate a Th1 shift. Some antidepressants would occur affecting these systems, acting on neurotransmitter balance (especially the 5-HT/NE balance) and expression levels of receptor subtypes, which in turn affect cytokine production and relative Th1/Th2 balance. It could be therefore hypothesized that the antidepressant-related increase in NE tone enhances the Th2 response, while the decrease in NE tone or the increase in 5-HT tone enhances the Th1 response. However, the neurotransmitter and Th1/Th2 balance modulation could be relative, aiming to restore physiological levels a previous imbalance in receptor sensitivity and cytokine production. The considerations on neuro-immunomodulation could represent an additional aid in the study of pathophysiology of psychiatric disorders and in the choice of specific antidepressants in specific clusters of symptoms, especially in comorbidity with internal pathologies. Furthermore limited data, reviewed here, have shown the effectiveness of some antidepressants as pure immunomodulators. However, these considerations are tentative and require experimental confirmation or refutation by future studies. PMID:23204981

SENSITIVITY AND SPECIFICITY OF INDIVIDUAL BERG BALANCE ITEMS COMPARED WITH THE TOTAL SCORE TO PREDICT FALLS IN COMMUNITY DWELLING ELDERLY INDIVIDUALS

Directory of Open Access Journals (Sweden)

Hazel Denzil Dias

2014-09-01

Full Text Available Background: Falls are a major problem in the elderly leading to increased morbidity and mortality in this population. Scores from objective clinical measures of balance have frequently been associated with falls in older adults. The Berg Balance Score (BBS which is a frequently used scale to test balance impairments in the elderly ,takes time to perform and has been found to have scoring inconsistencies. The purpose was to determine if individual items or a group of BBS items would have better accuracy than the total BBS in classifying community dwelling elderly individuals according to fall history. Method: 60 community dwelling elderly individuals were chosen based on a history of falls in this cross sectional study. Each BBS item was dichotomized at three points along the scoring scale of 0 – 4: between scores of 1 and 2, 2 and 3, and 3 and 4. Sensitivity (Sn, specificity (Sp, and positive (+LR and negative (-LR likelihood ratios were calculated for all items for each scoring dichotomy based on their accuracy in classifying subjects with a history of multiple falls. These findings were compared with the total BBS score where the cut-off score was derived from receiver operating characteristic curve analysis. Results: On analysing a combination of BBS items, B9 and B11 were found to have the best sensitivity and specificity when considered together. However the area under the curve of these items was 0.799 which did not match that of the total score (AUC= 0.837. A, combination of 4 BBS items - B9 B11 B12 and B13 also had good Sn and Sp but the AUC was 0.815. The combination with the AUC closest to that of the total score was a combination items B11 and B13. (AUC= 0.824. hence these two items can be used as the best predictor of falls with a cut off of 6.5 The ROC curve of the Total Berg balance Scale scores revealed a cut off score of 48.5. Conclusion: This study showed that combination of items B11 and B13 may be best predictors of falls in

SENSITIVITY AND SPECIFICITY OF INDIVIDUAL BERG BALANCE ITEMS COMPARED WITH THE TOTAL SCORE TO PREDICT FALLS IN COMMUNITY DWELLING ELDERLY INDIVIDUALS

Directory of Open Access Journals (Sweden)

Hazel Denzil Dias

2014-06-01

Full Text Available Background: Falls are a major problem in the elderly leading to increased morbidity and mortality in this population. Scores from objective clinical measures of balance have frequently been associated with falls in older adults. The Berg Balance Score (BBS which is a frequently used scale to test balance impairments in the elderly ,takes time to perform and has been found to have scoring inconsistencies. The purpose was to determine if individual items or a group of BBS items would have better accuracy than the total BBS in classifying community dwelling elderly individuals according to fall history. Method: 60 community dwelling elderly individuals were chosen based on a history of falls in this cross sectional study. Each BBS item was dichotomized at three points along the scoring scale of 0 – 4: between scores of 1 and 2, 2 and 3, and 3 and 4. Sensitivity (Sn, specificity (Sp, and positive (+LR and negative (-LR likelihood ratios were calculated for all items for each scoring dichotomy based on their accuracy in classifying subjects with a history of multiple falls. These findings were compared with the total BBS score where the cut-off score was derived from receiver operating characteristic curve analysis. Results: On analysing a combination of BBS items, B9 and B11 were found to have the best sensitivity and specificity when considered together. However the area under the curve of these items was 0.799 which did not match that of the total score (AUC= 0.837. A, combination of 4 BBS items - B9 B11 B12 and B13 also had good Sn and Sp but the AUC was 0.815. The combination with the AUC closest to that of the total score was a combination items B11 and B13. (AUC= 0.824. hence these two items can be used as the best predictor of falls with a cut off of 6.5 The ROC curve of the Total Berg balance Scale scores revealed a cut off score of 48.5. Conclusion: This study showed that combination of items B11 and B13 may be best predictors of falls in

Video and computer-based interactive exercises are safe and improve task-specific balance in geriatric and neurological rehabilitation: a randomised trial

Directory of Open Access Journals (Sweden)

Maayken van den Berg

2016-01-01

Full Text Available Question: Does adding video/computer-based interactive exercises to inpatient geriatric and neurological rehabilitation improve mobility outcomes? Is it feasible and safe? Design: Randomised trial. Participants: Fifty-eight rehabilitation inpatients. Intervention: Physiotherapist-prescribed, tailored, video/computer-based interactive exercises for 1 hour on weekdays, mainly involving stepping and weight-shifting exercises. Outcome measures: The primary outcome was the Short Physical Performance Battery (0 to 3 at 2 weeks. Secondary outcomes were: Maximal Balance Range (mm; Step Test (step count; Rivermead Mobility Index (0 to 15; activity levels; Activity Measure for Post Acute Care Basic Mobility (18 to 72 and Daily Activity (15 to 60; Falls Efficacy Scale (10 to 40, ED5D utility score (0 to 1; Reintegration to Normal Living Index (0 to 100; System Usability Scale (0 to 100 and Physical Activity Enjoyment Scale (0 to 126. Safety was determined from adverse events during intervention. Results: At 2 weeks the between-group difference in the primary outcome (0.1, 95% CI –0.2 to 0.3 was not statistically significant. The intervention group performed significantly better than usual care for Maximal Balance Range (38 mm difference after baseline adjustment, 95% CI 6 to 69. Other secondary outcomes were not statistically significant. Fifty-eight (55% of the eligible patients agreed to participate, 25/29 (86% completed the intervention and 10 (39% attended > 70% of sessions, with a mean of 5.6 sessions (SD 3.3 attended and overall average duration of 4.5 hours (SD 3.1. Average scores were 62 (SD 21 for the System Usability Scale and 62 (SD 8 for the Physical Activity Enjoyment Scale. There were no adverse events. Conclusion: The addition of video/computer-based interactive exercises to usual rehabilitation is a safe and feasible way to increase exercise dose, but is not suitable for all. Adding the exercises to usual rehabilitation resulted in task-specific

Regulating power for gas boilers in houses. Surplus power from wind power plants for natural gas boilers; Regulerkraft pae villakedelomraedet. Overskuds-el fra vindmoeller til naturgaskedler

Energy Technology Data Exchange (ETDEWEB)

Larsen, Michael; Frederiksen, Karsten V.

2011-08-15

The aim of the project is to clarify the potential development of a simple electric heating unit to gas installations in houses, so that natural gas for heating can be replaced with surplus wind power. The gas network in this way becomes an energy storage for power. In this preliminary project the aim is to estimate the value of these solutions and to verify in the lab, whether it is possible to establish and activate a simple and inexpensive electric heating unit on a typical gas boiler installation. In addition, it must be clarified whether it is possible to establish a simple communication with price signal from the balancing responsible. Based on the preliminary analyses and based on the electric heating unit, which is used in this project, it is estimated that there is a potential for the use of an electric heating unit on gas boilers in houses, and there is also a market, although there are limitations in relation to space and possibly also to the price. The price is estimated to be between 1,500 and 3,000 DKK per. installation (installed). However, this should be further investigated, including that the power balancing responsible /electricity trading companies assess the social value of using the electric heating unit as an element in the regulating power market. Regarding price signal, it is clear that communication opportunities are present at least with two of the balancing responsible companies, but it requires adaptation before a simple price signal to a gas boiler installation can be established. Price wise it is considered feasible. (LN)

Thermal balance of a LPG fuelled, four stroke SI engine with water addition

International Nuclear Information System (INIS)

Ozcan, Hakan; Soeylemez, M.S.

2006-01-01

The effect of water injection on a spark ignition engine thermal balance and performance has been experimentally investigated. A four stroke, four cylinder conventional engine was used with LPG (liquid petroleum gas) as fuel. Different water to fuel ratios by mass were used with variable engine speed ranging from 1000 to 4500 rpm. The results showed that as the water injection level to the engine increased, the percentage of useful work increased, while the losses other than unaccounted losses decreased. Additionally, the specific fuel consumption decreases, while the engine thermal efficiency increases. The average increase in the brake thermal efficiency for a 0.5 water to fuel mass ratio is approximately 2.7% over the use of LPG alone for the engine speed range studied

Complementing approaches to demonstrate chlorinated solvent biodegradation in a complex pollution plume: mass balance, PCR and compound-specific stable isotope analysis.

OpenAIRE

Courbet Christelle; Rivière Agnès; Jeannottat Simon; Rinaldi Sandro; Hunkeler Daniel; Bendjoudi Hocine; De Marsily Ghislain

2011-01-01

This work describes the use of different complementing methods (mass balance polymerase chain reaction assays and compound specific stable isotope analysis) to demonstrate the existence and effectiveness of biodegradation of chlorinated solvents in an alluvial aquifer. The solvent contaminated site is an old chemical factory located in an alluvial plain in France. As most of the chlorinated contaminants currently found in the groundwater at this site were produced by local industries at vario...

Asian natural gas--For a brighter '90s

International Nuclear Information System (INIS)

Klass, D.L.; Ohashi, Tadahiko

1991-01-01

The seminar was designed to focus on the business aspects of developing Asian natural gas resources by inclusion of papers on natural gas markets, the role of banks, and financial case histories of existing projects, and papers on commercial and industrial natural gas utilization. The utilization of natural gas was addressed by papers that targeted small-scale, industrial and utility usage of natural gas in electric power production, and by papers on air conditioning and other applications. Each of these topics is important to the development of the Asian natural gas industry. Together, they formed a balanced program when combined with the opening keynote addresses from Tokyo Gas Company, Ltd., and PETRONAS and a panel discussion on gas pricing. All papers have been processed separately for inclusion on the data base

Cascading of fluctuations in interdependent energy infrastructures: Gas-grid coupling

International Nuclear Information System (INIS)

Chertkov, Michael; Backhaus, Scott; Lebedev, Vladimir

2015-01-01

Highlights: • Fracturing and low cost of gas stimulated significant recent expansion of the natural gas networks. • Power system operators transition to gas as the main supply, also facing new reliability challenges. • Natural gas-fired generators vary burn-rates to balance fluctuating output of wind generation. • Impact of the gas-generator variations is seen in diffusive jitter of pressure within the gas network. • Fluctuating pressure impacts both reliability of natural gas deliveries and safety of pipeline operations. - Abstract: The revolution of hydraulic fracturing has dramatically increased the supply and lowered the cost of natural gas in the United States driving an expansion of natural gas-fired generation capacity in many electrical grids. Unrelated to the natural gas expansion, lower capital costs and renewable portfolio standards are driving an expansion of intermittent renewable generation capacity such as wind and photovoltaic generation. These two changes may potentially combine to create new threats to the reliability of these interdependent energy infrastructures. Natural gas-fired generators are often used to balance the fluctuating output of wind generation. However, the time-varying output of these generators results in time-varying natural gas burn rates that impact the pressure in interstate transmission pipelines. Fluctuating pressure impacts the reliability of natural gas deliveries to those same generators and the safety of pipeline operations. We adopt a partial differential equation model of natural gas pipelines and use this model to explore the effect of intermittent wind generation on the fluctuations of pressure in natural gas pipelines. The mean square pressure fluctuations are found to grow linearly in time with points of maximum deviation occurring at the locations of flow reversals.

The Swiss gas market - Facts and figures of today

International Nuclear Information System (INIS)

Pfander, M.

1999-01-01

This contribution presents a selection of the latest statistical data about the current state of development of the Swiss gas market. The sales and consumer structure areas are the focal points. The key data are clarified by graphics or shown in tabular form with brief comments. The following topics are dealt with: gas balance and sources of natural gas supply for Switzerland, natural gas sales by regions and cantons, energy consumption in the different consumption sectors, heating structure of residential accommodation according to energy sources, trend of natural gas consumption in Switzerland and elsewhere in Europe. (author)

Panorama 2014 - Short term trends in the gas industry

International Nuclear Information System (INIS)

Lecarpentier, Armelle

2013-12-01

Due to sustained competition between energy sources and an economic and geopolitical climate that is still unstable, gas growth has slowed. The year 2013 looks very mixed for the gas industry, particularly on the upstream side. Constraints on the supply of gas and the increased dependence on imports in consumer markets increase the vulnerability of the gas markets to the vagaries of geopolitical risks and result in tensions on the international market. In an environment full of uncertainties about future prices and contractual terms, investors are slow to initiate the projects necessary for a global gas balance in this decade. (author)

Study on Gas-liquid Falling Film Flow in Internal Heat Integrated Distillation Column

Science.gov (United States)

Liu, Chong

2017-10-01

Gas-liquid internally heat integrated distillation column falling film flow with nonlinear characteristics, study on gas liquid falling film flow regulation control law, can reduce emissions of the distillation column, and it can improve the quality of products. According to the distribution of gas-liquid mass balance internally heat integrated distillation column independent region, distribution model of heat transfer coefficient of building internal heat integrated distillation tower is obtained liquid distillation falling film flow in the saturated vapour pressure of liquid water balance, using heat transfer equation and energy equation to balance the relationship between the circulating iterative gas-liquid falling film flow area, flow parameter information, at a given temperature, pressure conditions, gas-liquid flow falling film theory makes the optimal parameters to achieve the best fitting value with the measured values. The results show that the geometric gas-liquid internally heat integrated distillation column falling film flow heat exchange area and import column thermostat, the average temperature has significant. The positive correlation between the heat exchanger tube entrance due to temperature difference between inside and outside, the heat flux is larger, with the increase of internal heat integrated distillation column temperature, the slope decreases its temperature rise, which accurately describes the internal gas-liquid heat integrated distillation tower falling film flow regularity, take appropriate measures to promote the enhancement of heat transfer. It can enhance the overall efficiency of the heat exchanger.

Assessing the optimized precision of the aircraft mass balance method for measurement of urban greenhouse gas emission rates through averaging

Directory of Open Access Journals (Sweden)

Alexie M. F. Heimburger

2017-06-01

Full Text Available To effectively address climate change, aggressive mitigation policies need to be implemented to reduce greenhouse gas emissions. Anthropogenic carbon emissions are mostly generated from urban environments, where human activities are spatially concentrated. Improvements in uncertainty determinations and precision of measurement techniques are critical to permit accurate and precise tracking of emissions changes relative to the reduction targets. As part of the INFLUX project, we quantified carbon dioxide (CO2, carbon monoxide (CO and methane (CH4 emission rates for the city of Indianapolis by averaging results from nine aircraft-based mass balance experiments performed in November-December 2014. Our goal was to assess the achievable precision of the aircraft-based mass balance method through averaging, assuming constant CO2, CH4 and CO emissions during a three-week field campaign in late fall. The averaging method leads to an emission rate of 14,600 mol/s for CO2, assumed to be largely fossil-derived for this period of the year, and 108 mol/s for CO. The relative standard error of the mean is 17% and 16%, for CO2 and CO, respectively, at the 95% confidence level (CL, i.e. a more than 2-fold improvement from the previous estimate of ~40% for single-flight measurements for Indianapolis. For CH4, the averaged emission rate is 67 mol/s, while the standard error of the mean at 95% CL is large, i.e. ±60%. Given the results for CO2 and CO for the same flight data, we conclude that this much larger scatter in the observed CH4 emission rate is most likely due to variability of CH4 emissions, suggesting that the assumption of constant daily emissions is not correct for CH4 sources. This work shows that repeated measurements using aircraft-based mass balance methods can yield sufficient precision of the mean to inform emissions reduction efforts by detecting changes over time in urban emissions.

[Influence of ski boots on balance performance].

Science.gov (United States)

Mildner, E; Lembert, S; Raschner, C

2010-03-01

Modern ski carving technique demands that skiers have a strong sense of balance and edge their skis with precision and feeling. Stiff ski boots facilitate the transfer of power to the ski but increase the difficulty of balancing. The aim of this study was to analyse the influence of ski boots on balance performance of alpine skiers. 76 experienced skiers (female 33/male 43) and 76 ski racers of the Skigymnasium Stams (female 31/male 45) were tested on the MFT S 3 Check with and without ski boots. Ski boots significantly influenced balance. There were also significant differences between experienced skiers and ski racers, but gender differences were minimal. In addition to general conditioning, skiers should utilise general and ski-specific balance and sensomotor training which could help in ski injury prevention, especially knee injuries. Georg Thieme Verlag KG Stuttgart, New York.

MHTGR steam generator on-line heat balance, instrumentation and function

International Nuclear Information System (INIS)

Klapka, R.E.; Howard, W.W.; Etzel, K.T.; Basol, M.; Karim, N.U.

1991-09-01

Instrumentation is used to measure the Modular High Temperature Gas-Cooled Reactor (MHTGR) steam generator dissimilar metal weld temperature during start-up testing. Additional instrumentation is used to determine an on-line heat balance which is maintained during the 40 year module life. In the process of calibrating the on-line heat balance, the helium flow is adjusted to yield the optimum boiling level in the steam generator relative to the dissimilar metal weld. After calibration is complete the weld temperature measurement is non longer required. The reduced boiling level range results in less restrictive steam generator design constraints

Balance (perceived and actual) and preferred stance width during pregnancy.

Science.gov (United States)

Jang, John; Hsiao, Katherine T; Hsiao-Wecksler, Elizabeth T

2008-05-01

Pregnant women often remark that their balance degrades during pregnancy; however, it appears that no studies have documented the gravida's perception of her balance nor measured direction-specific changes in balance throughout pregnancy or after delivery. Thirty women, fifteen pregnant and fifteen non-pregnant controls, were tested monthly and through 6-month postpartum. For each session, perceived degradation in sense of balance, laboratory-based balance measures, stance width, and the number of falls since the previous session were recorded. Laboratory-based balance measures, quantified by direction-specific measures of postural sway, were computed from ten 30s quiet-standing trials on a stationary force platform. Repeated-measures analysis of variance, paired t-tests, and Pearson correlations were use to examine group and time effects. For the pregnant group, perceived balance degradation and stance width were highly correlated (r = 0.94). Both increased during pregnancy (P r > 0.72) and also decreased significantly between the third trimester and postpartum (P pregnancy, but increased after delivery. Contrary to recent work suggesting fall rates of 25%, only 13% of our subjects (n = 2) fell during pregnancy. Perceived degradation in balance during pregnancy was strongly related to increasing postural sway instability in the anterior-posterior direction. Lateral stability was maintained during pregnancy and likely accomplished by increasing stance width.

The Association of Flexibility, Balance, and Lumbar Strength with Balance Ability: Risk of Falls in Older Adults

Directory of Open Access Journals (Sweden)

Emilio J. Martínez-López Emilio

2014-06-01

Full Text Available The purpose of the present study was to determine the effects of a proprioceptive training program on older adults, as well as to analyze the association between flexibility, balance and lumbar strength (physical fitness test with balance ability and fall risk (functional balance tests. This study was a controlled, longitudinal trial with a 12-week follow-up period. Subjects from a population of older adults were allocated to the intervention group (n = 28 or to the usual care (control group (n = 26. Subjects performed proprioceptive training twice weekly (6 specific exercises with Swiss ball and BOSU. Each session included 50 minutes (10 minutes of warm-up with slow walk, 10 minutes of mobility and stretching exercises, 30 minutes of proprioceptive exercises. The outcome variables were physical fitness (lower-body flexibility, hip-joint mobility, dynamic balance, static balance, and lumbar strength and functional balance (Berg scale and Tinetti test. The experimental group obtained significantly higher values than the control group in lower-body flexibility, dynamic balance, and lumbar strength (p = 0.019, p < 0.001, and p = 0.034 respectively. Hip-joint mobility, dynamic balance, and lumbar strength were positively associated with balance ability (p < 0.001, p < 0.001, and p = 0.014, respectively and the prevention of falls (p = 0.001, p < 0.001, and p = 0.017 respectively. These findings suggest that a 12-week proprioception program intervention (twice a week significantly improves flexibility, balance, and lumbar strength in older adults. Hip-joint mobility, dynamic balance and lumbar strength are positively associated to balance ability and the risk of falls in older adults. This proprioceptive training does not show a significant improvement in hip-joint mobility or static balance.

The energy and pressure balance in the corona

International Nuclear Information System (INIS)

McWhirter, R.W.P.; Wilson, R.

1976-01-01

This paper reviews theoretical models for the solar corona based on energy and pressure calculations. Processes included in these calculations are: (a) heating of the outer corona by mechanical waves; (b) convective out-flow of gas giving rise to the solar wind; (c) thermal conductions; (d) radiated power loss. Possible observations to help answer some of the outstanding questions about the energy balance are suggested. (author)

How much extra spot gas is there?

International Nuclear Information System (INIS)

Bros, Th.

2007-01-01

With the increase of European gas demand and the sharp decrease of local supply, security of supply is becoming an ever greater issue. However, liberalization tilts the traditional equilibrium based on long term 'take or pay' contracts between big suppliers and national distribution companies. Today, buying gas on the spot market is becoming more and more important to balance supply portfolio with a fast moving market share. But the way gas spot markets are operating is not well documented. It is very difficult to assess its impact on the European security of supply. Therefore, the aim of this article is to evaluate the amount of 'spot' liquefied natural gas (LNG) that could be found in case of a major supply disruption in pipe gas delivered to Europe

Region-specific greenhouse gas balances for rapeseed cultivation in Mecklenburg-West Pomerania; Regionalspezifische Treibhausgasbilanzen fuer den Rapsanbau in Mecklenburg-Vorpommern

Energy Technology Data Exchange (ETDEWEB)

Weirauch, Mareike [Landesforschungsanstalt fuer Landwirtschaft und Fischerei Mecklenburg-Vorpommern, Guelzow-Pruezen (Germany). Sachgebiet Nachwachsende Rohstoffe

2014-08-01

The renewable energy directive (RED, 2009128/EG) announced guidelines to reduce the greenhouse gas (GHG) emissions during the use of biofuels in comparison to the fossil fuels since 2009. The EU-RED contains maximum permissible values for the several production pathways of biofuels. On the basis of operating agriculture data (crop years 2011, 2012 and 2013) the current practical values of GHG emissions during the cultivation of rapeseed in Mecklenburg-West Pomerania have been analyzed in a present research project of the State Research Institute of Agriculture and Fishery Mecklenburg-West Pomerania. The results of the status quo analysis of the GHG emissions during rapeseed cultivation are compared with the EU-RED standard value for biodiesel (made of rapeseed) and optimization options for GHG reduction are discussed, which will make it possible to require the EU-RED 50% GHG reduction value in 2017.

Dairy Proteins and Energy Balance

DEFF Research Database (Denmark)

Bendtsen, Line Quist

High protein diets affect energy balance beneficially through decreased hunger, enhanced satiety and increased energy expenditure. Dairy products are a major source of protein. Dairy proteins are comprised of two classes, casein (80%) and whey proteins (20%), which are both of high quality......, but casein is absorbed slowly and whey is absorbed rapidly. The present PhD study investigated the effects of total dairy proteins, whey, and casein, on energy balance and the mechanisms behind any differences in the effects of the specific proteins. The results do not support the hypothesis that dairy...... proteins, whey or casein are more beneficial than other protein sources in the regulation of energy balance, and suggest that dairy proteins, whey or casein seem to play only a minor role, if any, in the prevention and treatment of obesity....

Greenhouse gasses emissions and energy balances of a non-vertically integrated sugar and ethanol supply chain: A case study in Argentina

International Nuclear Information System (INIS)

Acreche, Martín M.; Valeiro, Alejandro H.

2013-01-01

In order to address society's concerns regarding the sustainability of sugar and ethanol production and use, this paper calculates the energy and greenhouse gasses (GHG) emissions' balances of a non-vertically integrated sugarcane industry in Tucumán-Argentina. The essential operations involved in the sugar/ethanol production cycle were taken into account. Results show that this industry generated an energy balance of 3.4:1. GHG emissions during sugarcane production were 1824 and 2231 kg CO 2 eq. ha −1 year −1 for low and middle to high farms' technological levels, respectively. The mill process emitted 1187 kg CO 2 eq. ha −1 year −1 . The main factors influencing these balances were gas-oil and nitrogen fertilizers used in the agricultural stage, natural gas consumed by the sugar mill, and sugarcane burning (only for GHG balance). The impact of ethanol use in reducing GHG emissions under the current production scheme (6.8 Mg ha −1 of sugar + 380.9 kg ha −1 of ethanol), in final blends of 95% gasoline and 5% ethanol in vehicles, is negligible. A sensitivity analysis indicates that switching to 100% bagasse used as fuel in mill's boilers, ethanol being produced directly from sugarcane juice, and a final blend of 90% gasoline and 10% ethanol, an amount of 1746 kg CO 2 eq. ha −1 year −1 of GHG emissions could be avoided. - Highlights: ► Energy and GHG emissions' balances for the non-integrated sugar/ethanol industry in Tucumán-Argentina. ► The energy balance was positive, while there were important GHG emissions. ► Factors influencing both balances were gas-oil, N fertilizers, burning and natural gas. ► Ethanol use for reducing GHG emissions in the current production scheme is negligible. ► Results are promising, as the main factors influencing both balances are identified

Emission Characteristics of Gas-Fired Boilers based on Category-Specific Emission Factor from Field Measurements in Beijing, China

Science.gov (United States)

Itahashi, S.; Yan, X.; Song, G.; Yan, J.; Xue, Y.

2017-12-01

Gas-fired boilers will become the main stationary sources of NOx in Beijing. However, the knowledge of gas-fired boilers in Beijing is limited. In the present study, the emission characteristics of NOx, SO2, and CO from gas-fired boilers in Beijing were established using category-specific emission factors (EFs) from field measurements. In order to obtain category-specific EFs, boilers were classified through influence analysis. Factors such as combustion mode, boiler type, and installed capacity were considered critical for establishing EFs because they play significant roles in pollutant formation. The EFs for NOx, CO, and SO2 ranged from 1.42-6.86 g m-3, 0.05-0.67 g m-3 and 0.03-0.48 g m-3. The emissions of NOx, SO2, and CO for gas-fired boilers in Beijing were 11121 t, 468 t, and 222 t in 2014, respectively. The emissions were spatially allocated into grid cells with a resolution of 1 km × 1 km, and the results indicated that top emitters were in central Beijing. The uncertainties were quantified using a Monte Carlo simulation. The results indicated high uncertainties in CO (-157% to 154%) and SO2 (-127% to 182%) emissions, and relatively low uncertainties (-34% to 34%) in NOx emission. Furthermore, approximately 61.2% and 96.8% of the monitored chamber combustion boilers (CCBs) met the standard limits for NOx and SO2, respectively. Concerning NOx, low-NOx burners and NOx emission control measures are urgently needed for implementing of stricter standards. Adopting terminal control measures is unnecessary for SO2, although its concentration occasionally exceeds standard limits, because reduction of its concentration can be achieved thorough control of the sulfur content of natural gas at a stable low level. Furthermore, the atmospheric combustion boilers (ACBs) should be substituted with CCBs, because ACBs have a higher emission despite lower gross installed capacity. The results of this study will enable in understanding and controlling emissions from gas

Determination of low specific activity iodine-129 off-gas concentrations by GC separation and negative ionization mass spectrometry

International Nuclear Information System (INIS)

Fernandez, S.J.; Rankin, R.A.; McManus, G.J.; Nielsen, R.A.; Delmore, J.E.; Hohorst, F.A.; Murphy, L.P.

1983-09-01

This document is the final report of the laboratory development of a method for determining the specific activity of the 129 I emitted from a nuclear fuel reprocessing plant. The technique includes cryogenic sample collection, chemical form separation, quantitation by gas chromatography, and specific activity measurement of each chemical species by negative ionization mass spectrometry. The major conclusions were that both organic and elemental iodine can be quantitatively collected without fractionation and that specific activity measurements as low as one atom of 129 I per 10 5 atoms of 127 I are possible

Alignment of the NPL Mark II watt balance

International Nuclear Information System (INIS)

Robinson, I A

2012-01-01

To reach uncertainties in the region of 1 part in 10 8 a moving-coil watt balance not only requires the accurate measurement of voltage, resistance, velocity, mass and the acceleration due to gravity but, in addition, requires the apparatus to be adjusted correctly to minimize the second order effects which can reduce the accuracy of the measurement. This paper collects together the alignment and correction techniques that have been developed at NPL over many years and are required to minimize the uncertainty of the measurement. Some of these techniques are applicable to all watt balances, whilst a few are specific to watt balances that employ a conventional beam balance to support a circular coil in a radial magnetic field, such as the NPL Mark II watt balance, now known as the NRC watt balance. (paper)

Specific gas turbines for extreme peak-load

International Nuclear Information System (INIS)

Bellot, C.

1992-12-01

As with other European countries, in France peak consumption of electricity occurs during winter. Due to the increasing use of electricity for domestic heating, outside temperature greatly influences consumption (1 200 MW for a drop of 1 deg C). To meet requirements during cold spells, EDF has sought to determine which special facilities are best suited for extreme peak load conditions (i.e. offering short lifespan and minimum capital cost) and has studied the possibility of installing generation means in transformer substations (20 kV). This solution does not require extension of networks since these means are scattered near consumption areas. An experiment conducted on 3 Diesel generators of 800 kWe each at Senlis revealed some of the disadvantages of Diesel (maintenance requirements, polluting emissions and noise). EDF then examined, for this same application, the use of gas turbines, for which these drawbacks are significantly less. A study carried out under an EDF contract by the French manufacturer TURBOMECA showed that it is possible to design a small capacity gas turbine that can compete with Diesel generators, and that capital costs could be minimized by simplifying the machine, adapting its lifespan to extreme peak load needs, and taking advantage of lower cost provided by mass production. TURBOMECA defined the machine's characteristics (2 MW, 6 000 hours lifespan) and aerodynamic flow. It also estimated the cost of packaging. In terms of overall cost (including initial investment, maintenance and fuel) the gas turbine appears cheaper than Diesel generators for annual operation times of less than one hundred hours, which corresponds closely with extreme peak load use. The lower maintenance costs and the better availability counterbalance the higher capital cost (+6%) and the greater consumption (+50%). (author). 7 figs

Heterogeneous reactions and aerosol formation in flue gas cleaning by electron beam

International Nuclear Information System (INIS)

Baumann, W.; Jordan, S.; Leichsenring, C.H.; Maetzing, H.; Paur, H.R.; Schikarski, W.

1990-08-01

The electron beam dry scrubbing process is a simultaneous method for the removal of SO 2 and NO x from flue gas. By electron irradiation radicals (OH, O 2 H, O) are formed from the main flue gas components which oxidize NO x and SO 2 into the acids HNO 3 and H 2 SO 4 . These are then neutralized by the injection of NH 3 . A submicron aerosol consisting of ammonium salts is formed which is filtered from the offgas. The main pathways of the gas phase chemistry and product formation have been elucidated by experimental and theoretical studies. Back reactions which occur in the gas and the particle phase limit the energy efficiency of the process. By recirculation of irradiated gas into the reaction vessel (multiple irradiation) a significant improvement of removal yields was obtained. This enhancement of the energy efficiency requires the removal of products between the irradiation steps. Studies show that the material balance is complete. Deficits in the N and S balance of the process are due to the additional formation of molecular nitrogen and the deposition of ammonium sulfate in the ducts. Aerosol formation participates only with 30% in the material balance. The remaining 70% of the product are formed by surface reactions in the filter cake (40%) and in the ducts (30%). (orig.) With 38 figs., 29 tabs [de

Using balance training to improve the performance of youth basketball players.

Science.gov (United States)

Boccolini, Gabriele; Brazzit, Alessandro; Bonfanti, Luca; Alberti, Giampietro

2013-08-01

The aim of this study was to evaluate the effectiveness of 12 weeks of balance training to improve the balance and vertical jump abilities of young basketball players. Twenty-three players from two teams in the Under Fifteen Basketball Excellence category participated in the study. Participants were divided into two training groups: balance training (BAL, n  = 11) and isotonic training (ISO, n  = 12). Both groups were tested for balance and vertical jumps at the beginning of the competitive season and at the end of 12 weeks of specific training programme. All of the tests were performed in sustained bipodalic and monopodalic (both right and left) positions. The results showed that players who participated in balance training for 12 weeks, compared to players who trained with isotonic machines, exhibited a significantly increase in balance (bipodalic 28.3 %; right 41.4 %; left 45.8 %; p  training using unstable boards was an effective training method for improving balance and the vertical jump, which is a basketball-specific action that frequently occurs in this sport.

U.S. natural gas liquids supply and demand

International Nuclear Information System (INIS)

Urquhart, W.L.

1996-01-01

United States supply and demand situation for natural gas liquids (NGL) was reviewed. The presentation was in four parts: (1) key assumptions for U.S. NGL supply and demand, (2) specific balances for ethane, propane, and butane, (3) some of the key changes now occurring at the customer level, and how these might affect NGLs, and (4) a suggestion of where the future might deviate from projections so severely that projections could be fundamentally wrong. Despite such 'exogenous variables' higher demand projections downstream in the chemical industry were said to be appearing, albeit in scattered fashion. It was estimated that even fractionally higher economic growth could add 3.5 billion pounds to ethylene demand in the USA in the year 2005. 15 figs

A simple preparative free-flow electrophoresis joined with gratis gravity: I. Gas cushion injector and self-balance collector instead of multiple channel pump.

Science.gov (United States)

Chen, Su; Palmer, James F; Zhang, Wei; Shao, Jing; Li, Si; Fan, Liu-Yin; Sun, Ren; Dong, Yu-Chao; Cao, Cheng-Xi

2009-06-01

This paper describes a novel free-flow electrophoresis (FFE), which is joined with gratis gravity, gas cushion injector (GCI) and self-balance collector instead of multiple channel pump, for the purpose of preparative purification. The FFE was evaluated by systemic experiments. The results manifest that (i) even though one-channel peristaltic pump is used for the driving of background buffer, there is still stable flow in the FFE chamber; (ii) the stable flow is induced by the gravity-induced pressure due to the difference of buffer surfaces in the GCI and self-balance collector; (iii) the pulse flow of background buffer induced by the peristaltic pump is greatly reduced by the GCI with good compressibility of included air; (iv) the FFE can be well used for zone electrophoretic separation of amino acids; (v) up to 20 inlets simultaneous sample injection and up to five to tenfold condensation of amino acid can be achieved by combining the FFE device with the method of moving reaction boundary. To the best of authors' knowledge, FFE has not been used for such separation and condensation of amino acids. The relevant results achieved in the paper have evident significance for the development of preparative FFE.

BALANCE

Science.gov (United States)

Carmichael, H.

1953-01-01

A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

From comic relief to real understanding; how intestinal gas causes symptoms.

LENUS (Irish Health Repository)

Quigley, E M M

2012-02-03

Gas content and transit appear to conspire with the motor and sensory responses of the gut to produce gas related symptoms, both in normal individuals and especially in patients with irritable bowel syndrome (IBS). In relation to gas in IBS, two questions need to be addressed: do IBS patients produce more gas and what are the relationships between intestinal gas and symptoms? The balance of evidence seems to indicate that distension is a real phenomenon in IBS and that such distension accurately reflects gas content. More problematic is extrapolation of the observations relating symptoms to gas transit and retention.

Balancing the Energy-Water Nexus

Energy Technology Data Exchange (ETDEWEB)

Dell, Jan

2010-09-15

Optimizing the complex tradeoffs in the Energy-Water Nexus requires quantification of energy use, carbon emitted and water consumed. Water is consumed in energy production and is often a constraint to operations. More global attention and investment has been made on reducing carbon emissions than on water management. Review of public reporting by the largest 107 global power producers and 50 companies in the oil/gas industry shows broad accounting on carbon emissions but only partial reporting on water consumption metrics. If the Energy-Water Nexus is to be balanced, then water must also be measured to be optimally managed with carbon emissions.

Aerosol influence on energy balance of the middle atmosphere of Jupiter.

Science.gov (United States)

Zhang, Xi; West, Robert A; Irwin, Patrick G J; Nixon, Conor A; Yung, Yuk L

2015-12-22

Aerosols are ubiquitous in planetary atmospheres in the Solar System. However, radiative forcing on Jupiter has traditionally been attributed to solar heating and infrared cooling of gaseous constituents only, while the significance of aerosol radiative effects has been a long-standing controversy. Here we show, based on observations from the NASA spacecraft Voyager and Cassini, that gases alone cannot maintain the global energy balance in the middle atmosphere of Jupiter. Instead, a thick aerosol layer consisting of fluffy, fractal aggregate particles produced by photochemistry and auroral chemistry dominates the stratospheric radiative heating at middle and high latitudes, exceeding the local gas heating rate by a factor of 5-10. On a global average, aerosol heating is comparable to the gas contribution and aerosol cooling is more important than previously thought. We argue that fractal aggregate particles may also have a significant role in controlling the atmospheric radiative energy balance on other planets, as on Jupiter.

Nuclear reactor coolant and cover gas system

International Nuclear Information System (INIS)

George, J.A.; Redding, A.H.; Tower, S.N.

1976-01-01

A core cooling system is disclosed for a nuclear reactor of the type utilizing a liquid coolant with a cover gas above free surfaces of the coolant. The disclosed system provides for a large inventory of reactor coolant and a balanced low pressure cover gas arrangement. A flow restricting device disposed within a reactor vessel achieves a pressure of the cover gas in the reactor vessel lower than the pressure of the reactor coolant in the vessel. The low gas pressure is maintained over all free surfaces of the coolant in the cooling system including a coolant reservoir tank. Reactor coolant stored in the reservoir tank allows for the large reactor coolant inventory provided by the invention

World gas prospects: which role for the Middle East?

International Nuclear Information System (INIS)

Chabrelie, M.F.

1999-01-01

Since the early 1970's, the policies of energy diversification that have been implemented in the industrialized countries and in many developing countries have enabled natural gas to regularly increase its role in the world energy balance. Thus, during the past twenty years, natural gas to recorded the highest growth rate among fossil fuels, and its share in the energy market has gradually risen from 18.9 % in 1975 to 23 % in 1997. Today, thanks to favorable economic and environmental factors, natural gas has become the fuel of choice on many markets. Indeed, gas its blessed with a certain number of favorable assets (abundant reserves, flexibility, high-performance uses) which give it a major role in all energy demand forecast scenarios. The most spectacular development will indisputably take place in the power generation sector. Endowed with a considerable gas potential, the Middle East will represent an essential source of supply for many industrialized countries and several gas export projects, either by LNG tanker or by pipelines are currently being contemplated. During the past decade the contribution of natural gas to the energy mix also grew substantially in most Middle Eastern countries. The increase in gas demand should continue at a sustained rate, mainly driven by the power generation sector, petrochemicals and energy consumption by the hydrocarbons industry. These promising prospects for gas demand in most the markets in the region might lead to the development of an intra-regional network. However, although opportunities exist, the region will have to meet many challenges in order to contribute more largely to the world gas balance in the years to come. (author)

Oil and natural gas

International Nuclear Information System (INIS)

Riddell, C.H.

1993-01-01

The natural gas industry and market prospects in Canada are reviewed from a producer's point of view. In the first eight months of 1993, $2.3 billion in new equity was raised for natural gas exploration and production, compared to $900 million in 1991 and $1.2 billion in 1992. The number of wells drilled in the western Canada basin is expected to reach 8,000-9,000 in 1993, up from 5,600 in 1992, and Canadian producers' share of the North American natural gas market will probably reach 20% in 1993, up from 13% in 1986. Potential and proved gas supply in North America is ca 750 trillion ft 3 , of which ca 30% is in Canada. Factors affecting gas producers in Canada are the deregulated nature of the market, low costs for finding gas (finding costs in the western Canada basin are the lowest of any basin in North America), and the coming into balance of gas supply and demand. The former gas surplus has been reduced by expanding markets and by low prices which reduced the incentive to find new reserves. This surplus is largely gone, and prices have started rising although they are still lower than the pre-deregulation prices. Progress is continuing toward an integrated North American gas market in which a number of market hubs allow easy gas trading between producers and consumers. Commodity exchanges for hedging gas prices are beginning operation and electronic trading of gas contracts and pipeline capacity will also become a reality. 4 figs

Toward a protocol for quantifying the greenhouse gas balance and identifying mitigation options in smallholder farming systems

Science.gov (United States)

Rosenstock, T. S.; Rufino, M. C.; Butterbach-Bahl, K.; Wollenberg, E.

2013-06-01

Globally, agriculture is directly responsible for 14% of annual greenhouse gas (GHG) emissions and induces an additional 17% through land use change, mostly in developing countries (Vermeulen et al 2012). Agricultural intensification and expansion in these regions is expected to catalyze the most significant relative increases in agricultural GHG emissions over the next decade (Smith et al 2008, Tilman et al 2011). Farms in the developing countries of sub-Saharan Africa and Asia are predominately managed by smallholders, with 80% of land holdings smaller than ten hectares (FAO 2012). One can therefore posit that smallholder farming significantly impacts the GHG balance of these regions today and will continue to do so in the near future. However, our understanding of the effect smallholder farming has on the Earth's climate system is remarkably limited. Data quantifying existing and reduced GHG emissions and removals of smallholder production systems are available for only a handful of crops, livestock, and agroecosystems (Herrero et al 2008, Verchot et al 2008, Palm et al 2010). For example, fewer than fifteen studies of nitrous oxide emissions from soils have taken place in sub-Saharan Africa, leaving the rate of emissions virtually undocumented. Due to a scarcity of data on GHG sources and sinks, most developing countries currently quantify agricultural emissions and reductions using IPCC Tier 1 emissions factors. However, current Tier 1 emissions factors are either calibrated to data primarily derived from developed countries, where agricultural production conditions are dissimilar to that in which the majority of smallholders operate, or from data that are sparse or of mixed quality in developing countries (IPCC 2006). For the most part, there are insufficient emissions data characterizing smallholder agriculture to evaluate the level of accuracy or inaccuracy of current emissions estimates. Consequentially, there is no reliable information on the agricultural

18 CFR 367.4330 - Account 433, Balance transferred from income.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Account 433, Balance transferred from income. 367.4330 Section 367.4330 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY REGULATIONS UNDER THE PUBLIC UTILITY HOLDING COMPANY ACT OF 2005, FEDERAL POWER ACT AND NATURAL GAS...

Solving the gas transmission problem with consideration of the compressors

OpenAIRE

Bakhouya, Bouchra; de Wolf, Daniel

2008-01-01

In [7], De Wolf and Smeers consider the problem of the gas distribution through a network of pipelines. The problem was formulated as a cost minimization subject to nonlinear flow-pressure relations, material balances and pressure bounds. This model does not reflect any more the current situation on the gas market. Today, the transportation and gas buying functions are separated. This work considers the new situation for the transportation company. The objective for the tran...

Beyond the gas bubble

International Nuclear Information System (INIS)

Hilt, R.H.

1990-01-01

The deliverability issue currently being discussed within the natural gas industry involves both near-term and long-term questions. In the near-term, over the next two or three years, it is probable that the natural gas industry will need to mobilize for much greater levels of investment than have been the experience over the past few years. In the longer-term, it is expected that new opportunities for gas will arise as the nation seeks to meet increasing energy requirements within new environmental constraints. Methane for emissions control, CNG vehicles, expanded gas-fired electricity generation, and increased efficiency of traditional energy services are just a few examples. The issues in the longer-term center on the ability of the gas industry to meet increasing supply requirements reliably and at cost-competitive prices for these markets. This paper begins by reviewing the historical situation of gas deliverability that is the capability of the gas producing and transportation portions of the industry. The delivery system's ability to handle shifts in the centers of consumption and production is discussed, with an emphasis on regional problems of gas deliverability and potential bottlenecks. On the production side, the paper reviews the capability and the required investment necessary to handle an orderly transition to a stable supply and demand balance once the elusive bubble had finally disappeared

Experimental study of the effect of gas nature on plasma arc cutting of mild steel

International Nuclear Information System (INIS)

Kavka, T; Mašláni, A; Hrabovský, M; Křenek, P; Stehrer, T; Pauser, H

2013-01-01

This paper is devoted to the experimental investigation of arc cutting of mild steel using plasmas generated in gas and liquid media. Due to different chemical compositions, the examined media have different thermophysical properties, which affect the properties of the generated plasma and cutting performance. The experiments are performed on 15 mm mild steel plates using commercial equipment at 60 A to approach real operation conditions in application areas. The studied gases are chosen according to recommendations of the world's leading manufacturers of arc cutting equipment for mild steel. Specific differences between plasma gases are discussed from the point of view of properties of the gas and the generated plasma, amount of removed material, kerf shape and overall energy balance of the cutting process. The paper describes the role of exothermic reaction of iron oxidation for oxygen cutting and explains its neglect for liquid cutting. This paper explains the potential of facilitating the cutting process by modification of the plasma gas chemical composition and flow rate. (paper)

Balance ability measured with the Berg balance scale: a determinant of fall history in community-dwelling adults with leg amputation.

Science.gov (United States)

Wong, Christopher Kevin; Chen, Christine C; Blackwell, Wren M; Rahal, Rana T; Benoy, Stephany A

2015-01-01

Falls are common among adults with leg amputations and associated with balance confidence. But subjective confidence is not equivalent with physical ability. This multivariate analyses of community-dwelling adults with leg amputations examined relationships among individual characteristics, falls, balance ability and balance confidence. Cross-sectional study. Community-dwelling adults with leg amputations recruited from a support group and prosthetic clinic. Subjects provided self-reported medical/fall history, prosthetic functional use, and Activities-specific Balance Confidence (ABC) questionnaire data. Balance ability was assessed with the Berg Balance Scale (BBS). Fall incidence was categorized as any fall (one or more) and recurrent falls (more than one). Multivariate logistic regression analyzed relationships within the two fall categories. Cross tabulations and ANOVA analyzed differences among subcategories. Fifty-four subjects (mean age 56.8) with various etiologies, amputation levels, and balance abilities participated. 53.7% had any fall; 25.9% had recurrent falls. Models for both fall categories correctly classified fall history in > 70% of subjects with combinations of the variables ABC, BBS, body-mass-index, and amputation level. Falls occurred regardless of clinical characteristics. Total BBS and select item scores were independent determinants of fall history. Unlike other balance-impaired populations, adults with leg amputation and better balance ability had greater odds of falling.

Energy equivalence factor in gasoline to compressed vehicle natural gas substitution

International Nuclear Information System (INIS)

Agudelo Santamaria, John R; Amell Arrieta, Andres A

1992-01-01

In this paper, the authors show a model based in a vehicle energy balance used to obtain the ratio of energy equivalence of natural gas and petrol used as fuels in the vehicle. The model includes the engine, transmission and natural gas cylinders effects. The model has been applied to different colombian natural gases, it shows that Guajira natural gas has 14,5% lower ratio than Cusiana natural gas and 5,6% lower ratio than Apiay natural gas, these results shows a need in the study of colombian natural gases interchangeability

OPERATING SPECIFICATIONS OF CATALYTIC CLEANING OF GAS FROM BIOMASS GASIFICATION

Directory of Open Access Journals (Sweden)

Martin Lisý

2015-12-01

Full Text Available The paper focuses on the theoretical description of the cleaning of syngas from biomass and waste gasification using catalytic methods, and on the verification of the theory through experiments. The main obstruction to using syngas from fluid gasification of organic matter is the presence of various high-boiling point hydrocarbons (i.e., tar in the gas. The elimination of tar from the gas is a key factor in subsequent use of the gas in other technologies for cogeneration of electrical energy and heat. The application of a natural or artificial catalyst for catalytic destruction of tar is one of the methods of secondary elimination of tar from syngas. In our experiments, we used a natural catalyst (dolomite or calcium magnesium carbonate from Horní Lánov with great mechanical and catalytic properties, suitable for our purposes. The advantages of natural catalysts in contrast to artificial catalysts include their availability, low purchase prices and higher resilience to the so-called catalyst poison. Natural calcium catalysts may also capture undesired compounds of sulphure and chlorine. Our paper presents a theoretical description and analysis of catalytic destruction of tar into combustible gas components, and of the impact of dolomite calcination on its efficiency. The efficiency of the technology is verified in laboratories. The facility used for verification was a 150 kW pilot gasification unit with a laboratory catalytic filter. The efficiency of tar elimination reached 99.5%, the tar concentration complied with limits for use of the gas in combustion engines, and the tar content reached approximately 35 mg/mn3. The results of the measurements conducted in laboratories helped us design a pilot technology for catalytic gas cleaning.

Natural gas industry in USSR and in Central Europe: Domestic market and exports

International Nuclear Information System (INIS)

Kousnetzoff, N.

1993-01-01

This paper strikes the balance of natural gas industry in USSR and Central Europe and the state of domestic market and exports: natural gas accounting in Eastern Europe before the crisis, production capacity of the former USSR, impacts of crisis on natural gas consumption and long term forecasts are the main subjects described. 2 tab

Determination of low specific activity iodine-129 off-gas concentrations by GC separation and negative ionization mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Fernandez, S.J.; Rankin, R.A.; McManus, G.J.; Nielsen, R.A.; Delmore, J.E.; Hohorst, F.A.; Murphy, L.P.

1983-09-01

This document is the final report of the laboratory development of a method for determining the specific activity of the /sup 129/I emitted from a nuclear fuel reprocessing plant. The technique includes cryogenic sample collection, chemical form separation, quantitation by gas chromatography, and specific activity measurement of each chemical species by negative ionization mass spectrometry. The major conclusions were that both organic and elemental iodine can be quantitatively collected without fractionation and that specific activity measurements as low as one atom of /sup 129/I per 10/sup 5/ atoms of /sup 127/I are possible.

Gender-specific alteration of energy balance and circadian locomotor activity in the Crtc1 knockout mouse model of depression

KAUST Repository

Rossetti, Clara

2017-12-06

Obesity and depression are major public health concerns, and there is increasing evidence that they share etiological mechanisms. CREB-regulated transcription coactivator 1 (CRTC1) participates in neurobiological pathways involved in both mood and energy balance regulation. Crtc1 -/- mice rapidly develop a depressive-like and obese phenotype in early adulthood, and are therefore a relevant animal model to explore possible common mechanisms underlying mood disorders and obesity. Here, the obese phenotype of male and female Crtc1 -/- mice was further characterized by investigating CRTC1\\'s role in the homeostatic and hedonic regulation of food intake, as well as its influence on daily locomotor activity. Crtc1 -/- mice showed a strong gender difference in the homeostatic regulation of energy balance. Mutant males were hyperphagic and rapidly developed obesity on normal chow diet, whereas Crtc1 -/- females exhibited mild late-onset obesity without hyperphagia. Overeating of mutant males was accompanied by alterations in the expression of several orexigenic and anorexigenic hypothalamic genes, thus confirming a key role of CRTC1 in the central regulation of food intake. No alteration in preference and conditioned response for saccharine was observed in Crtc1 -/- mice, suggesting that mutant males\\' hyperphagia was not due to an altered hedonic regulation of food intake. Intriguingly, mutant males exhibited a hyperphagic behavior only during the resting (diurnal) phase of the light cycle. This abnormal feeding behavior was associated with a higher diurnal locomotor activity indicating that the lack of CRTC1 may affect circadian rhythmicity. Collectively, these findings highlight the male-specific involvement of CRTC1 in the central control of energy balance and circadian locomotor activity.

Gender-specific alteration of energy balance and circadian locomotor activity in the Crtc1 knockout mouse model of depression

KAUST Repository

Rossetti, Clara; Sciarra, Daniel; Petit, Jean-Marie; Eap, Chin B.; Halfon, Olivier; Magistretti, Pierre J.; Boutrel, Benjamin; Cardinaux, Jean-René

2017-01-01

Obesity and depression are major public health concerns, and there is increasing evidence that they share etiological mechanisms. CREB-regulated transcription coactivator 1 (CRTC1) participates in neurobiological pathways involved in both mood and energy balance regulation. Crtc1 -/- mice rapidly develop a depressive-like and obese phenotype in early adulthood, and are therefore a relevant animal model to explore possible common mechanisms underlying mood disorders and obesity. Here, the obese phenotype of male and female Crtc1 -/- mice was further characterized by investigating CRTC1's role in the homeostatic and hedonic regulation of food intake, as well as its influence on daily locomotor activity. Crtc1 -/- mice showed a strong gender difference in the homeostatic regulation of energy balance. Mutant males were hyperphagic and rapidly developed obesity on normal chow diet, whereas Crtc1 -/- females exhibited mild late-onset obesity without hyperphagia. Overeating of mutant males was accompanied by alterations in the expression of several orexigenic and anorexigenic hypothalamic genes, thus confirming a key role of CRTC1 in the central regulation of food intake. No alteration in preference and conditioned response for saccharine was observed in Crtc1 -/- mice, suggesting that mutant males' hyperphagia was not due to an altered hedonic regulation of food intake. Intriguingly, mutant males exhibited a hyperphagic behavior only during the resting (diurnal) phase of the light cycle. This abnormal feeding behavior was associated with a higher diurnal locomotor activity indicating that the lack of CRTC1 may affect circadian rhythmicity. Collectively, these findings highlight the male-specific involvement of CRTC1 in the central control of energy balance and circadian locomotor activity.

Assessing gas transit risks: Russia vs. the EU

International Nuclear Information System (INIS)

Le Coq, Chloé; Paltseva, Elena

2012-01-01

This paper proposes a Transit Risk Index (TRI) designed to assess the riskiness of pipeline gas imports and to study the effect of introducing new gas routes. TRI controls for gas dependency, transit route diversification, political risks of transit, pipeline rupture probability, and the balance of power between supplying and consuming countries along the transit route. Evaluating TRI for the EU-Russia gas trade, we show that the introduction of the Nord Stream pipeline would further widen already large disparities in gas risk exposure across the EU Member States. The gas risk exposure of the Member States served by Nord Stream would decline. In contrast, EU countries not connected to Nord Stream, but sharing other Russian gas transit routes with the Nord Stream countries, would face greater gas risk exposure. We discuss the implications of our analysis for the design of the common energy policy in the EU.

Balance and Gait Training With Augmented Feedback Improves Balance Confidence in People With Parkinson's Disease: A Randomized Controlled Trial.

Science.gov (United States)

Shen, Xia; Mak, Margaret K Y

2014-07-01

Background Fear of falling has been identified as an important and independent fall-risk predictor in patients with Parkinson's disease (PD). However, there are inconsistent findings on the effects of balance and gait training on balance confidence. Objective To explore whether balance and gait training with augmented feedback can enhance balance confidence in PD patients immediately after treatment and at 3- and 12-month follow-ups. Methods A total of 51 PD patients were randomly assigned to a balance and gait training (BAL) group or to an active control (CON) group. The BAL group received balance and gait training with augmented feedback, whereas CON participants received lower-limb strength training for 12 weeks. Outcome measures included Activities-Specific Balance Confidence (ABC) Scale, limits-of-stability test, single-leg-stance test, and spatiotemporal gait characteristics. All tests were administered before intervention (Pre), immediately after training (Post), and at 3 months (Post3m) and 12 months (Post12m) after treatment completion. Results The ABC score improved marginally at Post and significantly at Post3m and Post12m only in the BAL group (P point excursion at Post, but only the BAL group maintained the improvement at Post3m. The BAL group maintained significantly longer time-to-loss-of-balance during the single-leg stance test than the CON group at Post3m and Post12m (P balance confidence and balance and gait performance in patients with PD. © The Author(s) 2014.

Weight/balance portable test equipment

International Nuclear Information System (INIS)

Whitlock, R.W.

1994-01-01

This document shows the general layout, and gives a part description for the weight/balance test equipment. This equipment will aid in the regulation of the leachate loading of tanker trucks. The report contains four drawings with part specifications. The leachate originates from lined trenches

Global mass conservation method for dual-continuum gas reservoir simulation

KAUST Repository

Wang, Yi; Sun, Shuyu; Gong, Liang; Yu, Bo

2018-01-01

In this paper, we find that the numerical simulation of gas flow in dual-continuum porous media may generate unphysical or non-robust results using regular finite difference method. The reason is the unphysical mass loss caused by the gas compressibility and the non-diagonal dominance of the discretized equations caused by the non-linear well term. The well term contains the product of density and pressure. For oil flow, density is independent of pressure so that the well term is linear. For gas flow, density is related to pressure by the gas law so that the well term is non-linear. To avoid these two problems, numerical methods are proposed using the mass balance relation and the local linearization of the non-linear source term to ensure the global mass conservation and the diagonal dominance of discretized equations in the computation. The proposed numerical methods are successfully applied to dual-continuum gas reservoir simulation. Mass conservation is satisfied while the computation becomes robust. Numerical results show that the location of the production well relative to the large-permeability region is very sensitive to the production efficiency. It decreases apparently when the production well is moved from the large-permeability region to the small-permeability region, even though the well is very close to the interface of the two regions. The production well is suggested to be placed inside the large-permeability region regardless of the specific position.

Global mass conservation method for dual-continuum gas reservoir simulation

KAUST Repository

Wang, Yi

2018-03-17

In this paper, we find that the numerical simulation of gas flow in dual-continuum porous media may generate unphysical or non-robust results using regular finite difference method. The reason is the unphysical mass loss caused by the gas compressibility and the non-diagonal dominance of the discretized equations caused by the non-linear well term. The well term contains the product of density and pressure. For oil flow, density is independent of pressure so that the well term is linear. For gas flow, density is related to pressure by the gas law so that the well term is non-linear. To avoid these two problems, numerical methods are proposed using the mass balance relation and the local linearization of the non-linear source term to ensure the global mass conservation and the diagonal dominance of discretized equations in the computation. The proposed numerical methods are successfully applied to dual-continuum gas reservoir simulation. Mass conservation is satisfied while the computation becomes robust. Numerical results show that the location of the production well relative to the large-permeability region is very sensitive to the production efficiency. It decreases apparently when the production well is moved from the large-permeability region to the small-permeability region, even though the well is very close to the interface of the two regions. The production well is suggested to be placed inside the large-permeability region regardless of the specific position.

Balance circuit classes to improve balance among rehabilitation inpatients: a protocol for a randomised controlled trial.

Science.gov (United States)

Treacy, Daniel; Schurr, Karl; Sherrington, Catherine

2013-07-20

Impaired balance and mobility are common among rehabilitation inpatients. Poor balance and mobility lead to an increased risk of falling. Specific balance exercise has been shown to improve balance and reduce falls within the community setting. However few studies have measured the effects of balance exercises on balance within the inpatient setting. A single centre, randomised controlled trial with concealed allocation, assessor blinding and intention-to-treat analysis. One hundred and sixty two patients admitted to the general rehabilitation ward at Bankstown-Lidcombe Hospital will be recruited. Eligible participants will have no medical contraindications to exercise and will be able to: fully weight bear; stand unaided independently for at least 30 seconds; and participate in group therapy sessions with minimal supervision. Participants will be randomly allocated to an intervention group or usual-care control group. Both groups will receive standard rehabilitation intervention that includes physiotherapy mobility training and exercise for at least two hours on each week day. The intervention group will also receive six 1-hour circuit classes of supervised balance exercises designed to maximise the ability to make postural adjustments in standing, stepping and walking. The primary outcome is balance. Balance will be assessed by measuring the total time the participant can stand unsupported in five different positions; feet apart, feet together, semi-tandem, tandem and single-leg-stance. Secondary outcomes include mobility, self reported physical functioning, falls and hospital readmissions. Performance on the outcome measures will be assessed before randomisation and at two-weeks and three-months after randomisation by physiotherapists unaware of intervention group allocation. This study will determine the impact of additional balance circuit classes on balance among rehabilitation inpatients. The results will provide essential information to guide evidence

Net energy balance of tokamak fusion power plants

International Nuclear Information System (INIS)

Buende, R.

1981-10-01

The net energy balance for a tokamak fusion power plant was determined by using a PWR power plant as reference system, replacing the fission-specific components by fusion-specific components and adjusting the non-reactor-specific components to altered conditions. For determining the energy input to the fusion plant a method was developed that combines the advantages of the energetic input-output method with those of process chain analysis. A comparison with PWR, HTR, FBR, and coal-fired power plants is made. As a result the net energy balance of the fusion power plant turns out to be more advantageous than that of an LWR, HTR or coal-fired power plant and nearly in the same range as FBR power plants. (orig.)

Influence of different storage times and temperatures on blood gas and acid-base balance in ovine venous blood

Directory of Open Access Journals (Sweden)

H.A. Hussein

2013-01-01

Full Text Available The present study was designed to investigate the effects of storage temperature and time on blood gas and acid-base balance of ovine venous blood. Ten clinically healthy sheep were used in this study. A total number of 30 blood samples, were divided into three different groups, and were stored in a refrigerator adjusted to +4 ºC (Group I, n = 10, at RT of about 22-25 ºC (Group II, n = 10 and in an incubator adjusted to 37 ºC (Group III, n = 10 for up to 48 h. Blood samples were analysed for blood gas and acid-base indices at 0, 1, 2, 3, 4, 5, 6, 12, 24 and 48 h of storage. In comparison to the baseline value (0, there were significant decreases of blood pH of samples stored at RT and in the incubator after 1 h (p<0.05, the pH value of refrigerated blood samples exhibited insignificant changes during the study (p<0.05. Mean values of pCO2 showed a significant increase in Group I and Group III after 1 h then a progressive decrease after 12 h in all Groups. Mean pO2 values were significantly higher for Group I after 2 h and for Groups II and III after 1 h (p<0.05. In general, base excess decreased significantly for all the groups during the study especially in Groups II and III. In comparison with baseline values, in all groups, bicarbonate (HCO3 increased between 1 h and 6 h (p<0.05, and later decreased at the end of the study (p<0.05. In conclusion, status of acid-base indices of the samples stored at refrigerator and RT were found within normal reference range and it may be of clinical diagnostic use for up to 6 h.

Global particle balance and wall recycling properties of long duration discharges on TRIAM-1M

International Nuclear Information System (INIS)

Sakamoto, M.; Yuno, M.; Itoh, S.

2003-01-01

The longest tokamak discharge with the duration of 11406 s (3 h 10 min) was achieved. The global particle balance has been investigated. In the longest discharge, the global balance between the particle absorption and release of the wall was achieved around t∼30 min and then the fueling was automatically stopped. After that the plasma density was maintained by the recycling flux alone until the end of the discharge. The maximum wall inventory is about 3.6 x 10 20 H at t ∼ 30 min but it is finally released from the wall at the end of the discharge. The global balance seems to be caused by the increase in the hydrogen release from the main chamber resulting from its temperature rise. Moreover, it has been observed a large difference between properties of wall recycling in the continuous gas feed case (i.e. static condition) and the additional gas puff case (i.e. dynamic condition). In the static condition, the effective particle confinement time increases almost linearly to about 10 s during the one-minute discharge. In the dynamic condition, the decay time of the electron density just after the gas puff, i.e. the effective particle confinement time, is 0.2 to 0.3 s during the one-minute discharge. The large difference was also reproduced in the longest discharge. It is considered that the enhanced wall pumping is caused by the increase in fluxes of the diffused ions and charge exchange neutrals due to the additional gas puff. (author)

Panorama 2015 - Short term trends in the gas industry

International Nuclear Information System (INIS)

Le Carpentier, Armelle

2014-12-01

For the third consecutive year, growth in gas demand is slowing down. The year of 2014 is marked by lower activity in the global gas industry at all stages in the chain. This can be explained by increased competition between energies (coal, renewables), the economic slowdown and the mild weather conditions which have put a brake on expansion of the gas demand (Europe, Asia) and led to high stock levels. These developments have pushed market prices downwards and modified inter-regional balancing flows. (author)

Numerical modeling of underground storage system for natural gas

Science.gov (United States)

Ding, J.; Wang, S.

2017-12-01

Natural gas is an important type of base-load energy, and its supply needs to be adjusted according to different demands in different seasons. For example, since natural gas is increasingly used to replace coal for winter heating, the demand for natural gas in winter is much higher than that in other seasons. As storage systems are the essential tools for balancing seasonal supply and demand, the design and simulation of natural gas storage systems form an important research direction. In this study, a large-scale underground storage system for natural gas is simulated based on theoretical analysis and finite element modeling.It is proven that the problem of axi-symmetric Darcy porous flow of ideal gas is governed by the Boussinesq equation. In terms of the exact solution to the Boussinesq equation, the basic operating characteristics of the underground storage system is analyzed, and it is demonstrated that the propagation distance of the pore pressure is proportional to the 1/4 power of the mass flow rate and to the 1/2 power of the propagation time. This quantitative relationship can be used to guide the overall design of natural gas underground storage systems.In order to fully capture the two-way coupling between pore pressure and elastic matrix deformation, a poro-elastic finite element model for natural gas storage is developed. Based on the numerical model, the dynamic processes of gas injection, storage and extraction are simulated, and the corresponding time-dependent surface deformations are obtained. The modeling results not only provide a theoretical basis for real-time monitoring for the operating status of the underground storage system through surface deformation measurements, but also demonstrate that a year-round balance can be achieved through periodic gas injection and extraction.This work is supported by the CAS "100 talents" Program and the National Natural Science Foundation of China (41371090).

REPRODUCIBILITY OF THE MODIFIED STAR EXCURSION BALANCE TEST COMPOSITE AND SPECIFIC REACH DIRECTION SCORES.

Science.gov (United States)

van Lieshout, Remko; Reijneveld, Elja A E; van den Berg, Sandra M; Haerkens, Gijs M; Koenders, Niek H; de Leeuw, Arina J; van Oorsouw, Roel G; Paap, Davy; Scheffer, Else; Weterings, Stijn; Stukstette, Mirelle J

2016-06-01

The mSEBT is a screening tool used to evaluate dynamic balance. Most research investigating measurement properties focused on intrarater reliability and was done in small samples. To know whether the mSEBT is useful to discriminate dynamic balance between persons and to evaluate changes in dynamic balance, more research into intra- and interrater reliability and smallest detectable change (synonymous with minimal detectable change) is needed. To estimate intra- and interrater reliability and smallest detectable change of the mSEBT in adults at risk for ankle sprain. Cross-sectional, test-retest design. Fifty-five healthy young adults participating in sports at risk for ankle sprain participated (mean ± SD age, 24.0 ± 2.9 years). Each participant performed three test sessions within one hour and was rated by two physical therapists (session 1, rater 1; session 2, rater 2; session 3, rater 1). Participants and raters were blinded for previous measurements. Normalized composite and reach direction scores for the right and left leg were collected. Analysis of variance was used to calculate intraclass correlation coefficient values for intra- and interrater reliability. Smallest detectable change values were calculated based on the standard error of measurement. Intra- and interrater reliability for both legs was good to excellent (intraclass correlation coefficient ranging from 0.87 to 0.94). The intrarater smallest detectable change for the composite score of the right leg was 7.2% and for the left 6.2%. The interrater smallest detectable change for the composite score of the right leg was 6.9% and for the left 5.0%. The mSEBT is a reliable measurement instrument to discriminate dynamic balance between persons. Most smallest detectable change values of the mSEBT appear to be large. More research is needed to investigate if the mSEBT is usable for evaluative purposes. Level 2.

Energy in Italian regions. Energy balance

International Nuclear Information System (INIS)

Catoni, P. G.; Perrella, G.

1998-01-01

This paper reports the syntheses of regional energy balance and the elaboration of the most important energy index from 1990 to 1996 at this scope a specific methodology. Pentec (territorial energy planning ecompatible) is pointed [it

Application of an entry-exit tariff model to the gas transport system in Spain

International Nuclear Information System (INIS)

Alonso, Alejandro; Serrano, Miguel; Olmos, Luis

2010-01-01

Under an entry-exit gas tariff system, reservation of capacity is split into entry capacity, to transport gas from the injection points to a virtual balancing point, and exit capacity, to transport gas from the balancing point to the exit points in the system. Entry-exit tariff for gas transport systems have been recommended by the 3rd EU Energy Package, since they are cost reflective, facilitate gas trade and can provide signals for the location of gas injections or off-takes. The advisability of applying an entry-exit tariff system is discussed in this paper. Apart from this, authors propose an entry-exit tariff model and apply it to compute charges for the Spanish gas transport system in 2009. Results produced by the model are presented as coefficients which should multiply the current postal transport tariff. The paper concludes that entry-exit tariffs would be useful location signals which would result in a better use of the gas transport system in Spain. In those cases where demand exceeds available capacity, as it occurs at the congested connection with France, entry-exit tariffs could be supplemented by capacity charges at entry points resulting from auctions. (author)

Active bypass flow control for a seal in a gas turbine engine

Science.gov (United States)

Ebert, Todd A.; Kimmel, Keith D.

2017-01-10

An active bypass flow control system for controlling bypass compressed air based upon leakage flow of compressed air flowing past an outer balance seal between a stator and rotor of a first stage of a gas turbine in a gas turbine engine is disclosed. The active bypass flow control system is an adjustable system in which one or more metering devices may be used to control the flow of bypass compressed air as the flow of compressed air past the outer balance seal changes over time as the outer balance seal between the rim cavity and the cooling cavity wears. In at least one embodiment, the metering device may include a valve formed from one or more pins movable between open and closed positions in which the one pin at least partially bisects the bypass channel to regulate flow.

Greenhouse gas balances and mitigation costs of 70 modern Germany-focused and 4 traditional biomass pathways including land-use change effects

International Nuclear Information System (INIS)

Sterner, Michael; Fritsche, Uwe

2011-01-01

With Germany as the point of energy end-use, 70 current and future modern pathways plus 4 traditional biomass pathways for heat, power and transport have been compiled and examined in one single greenhouse gas (GHG) balancing assessment. This is needed to broaden the narrow focus on biofuels for transport and identify the role of bioenergy in GHG mitigation. Sensitivity analysis for land-use changes and fossil reference systems are included. Co-firing of woody biomass and fermentation of waste biomass are the most cost-efficient and effective biomass applications for GHG emission reduction in modern pathways. Replacing traditional biomass with modern biomass applications offers an underestimated economic potential of GHG emission reduction. The range of maximum CO 2 equivalent GHG reduction potential of bioenergy is identified in a range of 2.5–16 Gt a −1 in 2050 (5–33% of today’s global GHG emissions), and has an economic bioenergy potential of 150 EJ a −1 .

Comparing the effects of balance training with and without cognitive tasks on the quality of life and balance performance in community-dwelling older adults: a single-blind randomized clinical trial

OpenAIRE

Ehsan Sinaei; Fahimeh Kamali; Ahmadreza Nematollahi; Zahra Etminan

2016-01-01

Background: Aging process can deteriorate the ability to maintain balance, specifically under dual-task conditions. Thus far, different methods of exercises therapy have been applied to improve balance performance of older adults. The present study was designed to compare the effects of two protocols of balance training on the quality of life (QoL) and balance performance in older adults with mild balance impairments. Methods: Twenty-four older adults over 60 years old were ...

Energy balances of OECD countries 1993-1994

International Nuclear Information System (INIS)

1996-01-01

This work contains a compilation of data on the supply and consumption of coal, oil, gas, electricity, heat, renewable combustible and waste presented in energy balances. The figures are expressed in million tonnes of oil equivalent. Historical tables summarize key energy and economic indicators as well as production, trade and final consumption data. Each issue includes definitions of products and flows and explanatory notes on the individual country data as well as conversion factors from original units to tonnes of oil equivalent. (authors). figs., tabs

Multi-Gas Sensor

Science.gov (United States)

Sachse, Glenn W. (Inventor); Wang, Liang-Guo (Inventor); LeBel, Peter J. (Inventor); Steele, Tommy C. (Inventor); Rana, Mauro (Inventor)

1999-01-01

A multi-gas sensor is provided which modulates a polarized light beam over a broadband of wavelengths between two alternating orthogonal polarization components. The two orthogonal polarization components of the polarization modulated beam are directed along two distinct optical paths. At least one optical path contains one or more spectral discrimination element, with each spectral discrimination element having spectral absorption features of one or more gases of interest being measured. The two optical paths then intersect, and one orthogonal component of the intersected components is transmitted and the other orthogonal component is reflected. The combined polarization modulated beam is partitioned into one or more smaller spectral regions of interest where one or more gases of interest has an absorption band. The difference in intensity between the two orthogonal polarization components is then determined in each partitioned spectral region of interest as an indication of the spectral emission/absorption of the light beam by the gases of interest in the measurement path. The spectral emission/absorption is indicative of the concentration of the one or more gases of interest in the measurement path. More specifically, one embodiment of the present invention is a gas filter correlation radiometer which comprises a polarizer, a polarization modulator, a polarization beam splitter, a beam combiner, wavelength partitioning element, and detection element. The gases of interest are measured simultaneously and, further, can be measured independently or non-independently. Furthermore, optical or electronic element are provided to balance optical intensities between the two optical paths.

[BALANCED SCORECARD AS A MANAGEMENT TOOL IN CLINICAL NUTRITION].

Science.gov (United States)

Gutiérrez López, Cristina; Mauriz, Jose L; Culebras, Jesús M

2015-07-01

Nowadays, balanced scorecards have updated traditional management systems in the business sector. In this way, Kaplan and Norton propose performance measurement through several perspectives with a logical sequence: internal processes and learning impact client services, so that financial performance is affected. The aim of the present paper is to analyze the main characteristics of balanced scorecard when it is applied to non-for-profit companies and, specifically to the health sector in the clinical nutrition field. This model improves the economic vision of management with clinical indicators that represent healthcare professional's perspective. The balanced scorecard would allow a proper monitoring and tracking system for the main healthcare indicators. This contributes to a better control in comparison with standards that are associated with adequate quality assistance. Owing to the role of management accounting and cost calculations, the definition of healthcare professionals as clients or users, and clinical results relevance, it is necessary to adapt the balanced scorecard to the specific characteristics of the clinical field, redefining both perspectives and indicators. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Controversies Regarding Costs, Uncertainties and Benefits Specific to Shale Gas Development

Directory of Open Access Journals (Sweden)

Jianu Daniel Muresan

2015-03-01

Full Text Available The shale gas exploration and development is now a delicate and controversial subject. It is often assumed that unconventional exploration and extraction automatically brings prosperity for local, national and regional economies. In this paper, we argue that shale gas development requires a contextualized understanding of regional issues. We are also trying to identify the opportunities and the risks of shale gas development in Eastern Europe (referring to Romania’s case and offer a cost-benefit analysis model that may be of interest to any policymakers and investors.

Do kinematic metrics of walking balance adapt to perturbed optical flow?

Science.gov (United States)

Thompson, Jessica D; Franz, Jason R

2017-08-01

Visual (i.e., optical flow) perturbations can be used to study balance control and balance deficits. However, it remains unclear whether walking balance control adapts to such perturbations over time. Our purpose was to investigate the propensity for visuomotor adaptation in walking balance control using prolonged exposure to optical flow perturbations. Ten subjects (age: 25.4±3.8years) walked on a treadmill while watching a speed-matched virtual hallway with and without continuous mediolateral optical flow perturbations of three different amplitudes. Each of three perturbation trials consisted of 8min of prolonged exposure followed by 1min of unperturbed walking. Using 3D motion capture, we analyzed changes in foot placement kinematics and mediolateral sacrum motion. At their onset, perturbations elicited wider and shorter steps, alluding to a more cautious, general anticipatory balance control strategy. As perturbations continued, foot placement tended toward values seen during unperturbed walking while step width variability and mediolateral sacrum motion concurrently increased. Our findings suggest that subjects progressively shifted from a general anticipatory balance control strategy to a reactive, task-specific strategy using step-to-step adjustments. Prolonged exposure to optical flow perturbations may have clinical utility to reinforce reactive, task-specific balance control through training. Copyright © 2017 Elsevier B.V. All rights reserved.

Prediction of gas volume fraction in fully-developed gas-liquid flow in a vertical pipe

International Nuclear Information System (INIS)

Islam, A.S.M.A.; Adoo, N.A.; Bergstrom, D.J.; Wang, D.F.

2015-01-01

An Eulerian-Eulerian two-fluid model has been implemented for the prediction of the gas volume fraction profile in turbulent upward gas-liquid flow in a vertical pipe. The two-fluid transport equations are discretized using the finite volume method and a low Reynolds number κ-ε turbulence model is used to predict the turbulence field for the liquid phase. The contribution to the effective turbulence by the gas phase is modeled by a bubble induced turbulent viscosity. For the fully-developed flow being considered, the gas volume fraction profile is calculated using the radial momentum balance for the bubble phase. The model potentially includes the effect of bubble size on the interphase forces and turbulence model. The results obtained are in good agreement with experimental data from the literature. The one-dimensional formulation being developed allows for the efficient assessment and further development of both turbulence and two-fluid models for multiphase flow applications in the nuclear industry. (author)

Prediction of gas volume fraction in fully-developed gas-liquid flow in a vertical pipe

Energy Technology Data Exchange (ETDEWEB)

Islam, A.S.M.A.; Adoo, N.A.; Bergstrom, D.J., E-mail: nana.adoo@usask.ca [University of Saskatchewan, Department of Mechanical Engineering, Saskatoon, SK (Canada); Wang, D.F. [Canadian Nuclear Laboratories, Chalk River, ON (Canada)

2015-07-01

An Eulerian-Eulerian two-fluid model has been implemented for the prediction of the gas volume fraction profile in turbulent upward gas-liquid flow in a vertical pipe. The two-fluid transport equations are discretized using the finite volume method and a low Reynolds number κ-ε turbulence model is used to predict the turbulence field for the liquid phase. The contribution to the effective turbulence by the gas phase is modeled by a bubble induced turbulent viscosity. For the fully-developed flow being considered, the gas volume fraction profile is calculated using the radial momentum balance for the bubble phase. The model potentially includes the effect of bubble size on the interphase forces and turbulence model. The results obtained are in good agreement with experimental data from the literature. The one-dimensional formulation being developed allows for the efficient assessment and further development of both turbulence and two-fluid models for multiphase flow applications in the nuclear industry. (author)

Macroscopic balance model for wave rotors

Science.gov (United States)

Welch, Gerard E.

1996-01-01

A mathematical model for multi-port wave rotors is described. The wave processes that effect energy exchange within the rotor passage are modeled using one-dimensional gas dynamics. Macroscopic mass and energy balances relate volume-averaged thermodynamic properties in the rotor passage control volume to the mass, momentum, and energy fluxes at the ports. Loss models account for entropy production in boundary layers and in separating flows caused by blade-blockage, incidence, and gradual opening and closing of rotor passages. The mathematical model provides a basis for predicting design-point wave rotor performance, port timing, and machine size. Model predictions are evaluated through comparisons with CFD calculations and three-port wave rotor experimental data. A four-port wave rotor design example is provided to demonstrate model applicability. The modeling approach is amenable to wave rotor optimization studies and rapid assessment of the trade-offs associated with integrating wave rotors into gas turbine engine systems.

Design study of shaft face seal with self-acting lift augmentation. 4: Force balance

Science.gov (United States)

Ludwig, L. P.; Zuk, J.; Johnson, R. L.

1972-01-01

A method for predicting the operating film thickness of self-acting seals is described. The analysis considers a 16.76-cm mean diameter seal that is typical of large gas turbines for aircraft. Four design points were selected to cover a wide range of operation for advanced engines. This operating range covered sliding speeds of 61 to 153 m/sec, sealed pressures of 45 to 217 N/sq cm abs, and gas temperatures of 311 to 977 K. The force balance analysis revealed that the seal operated without contact over the operating range with gas film thicknesses ranging between 0.00046 to 0.00119 cm, and with gas leakage rates between 0.01 to 0.39 scmm.

Shale-gas wells as virtual storage for supporting intermittent renewables

International Nuclear Information System (INIS)

Knudsen, Brage Rugstad; Foss, Bjarne

2017-01-01

Mature shale-gas wells possess a property that enables cyclic production and shut-in without incurring revenue losses. Based on this property, we suggest that fields with mature shale-gas wells may act as virtual gas storage for supplying fast-ramping gas power plants which balance intermittent renewable generation. By enabling gas supply to power plants to circumvent intermediate third-party storage, we argue that the proposed integration facilitates demand-driven gas production, and discuss how the scheme may support utilization of renewables and reduce supply-related greenhouse-gas emissions in electricity generation. - Highlights: • A novel integration strategy of shale gas and renewable electricity generation. • Mature shale-gas wells enable shut-ins without incurring revenue losses. • This property enables the use mature shale-gas wells as virtual gas storage. • Proposed scheme facilitates demand-driven gas production. • Omitting intermediate gas storage reduces GHG emissions from producer to end-user.

Royalty financing for the oil and gas industry

International Nuclear Information System (INIS)

Read, F. M. D.

1998-01-01

Key concepts in royalty financing for the oil and gas industry are described. The basic significance of royalty financing for a public company is that financing is 'off balance sheet', and can be used to achieve objectives that neither debt, equity, nor outright sale of assets or farm-outs can accomplish. Royalty financing can provide increased available capital or debt reduction while maintaining the full gross share of reserve and production volumes on the books. This paper provides an overview of the field of royalty financing, with an appreciation of the benefits, reviews each of the financial alternatives (debt, equity, farmout and or sale of assets to reduce capital requirements), and provides examples of specific application of royalty financing. It is claimed that this type of financing, which has been available to the mining sector for some time, is a useful alternative to other financing instruments to acquire new oil and gas assets, to develop new areas, to implement enhanced recovery projects or to carry out mergers and acquisitions. Used judiciously, royalty financing can provide significant benefits to both the working interest owner and his shareholders, as well as the royalty company

Typical balance exercises or exergames for balance improvement?

Science.gov (United States)

Gioftsidou, Asimenia; Vernadakis, Nikolaos; Malliou, Paraskevi; Batzios, Stavros; Sofokleous, Polina; Antoniou, Panagiotis; Kouli, Olga; Tsapralis, Kyriakos; Godolias, George

2013-01-01

Balance training is an effective intervention to improve static postural sway and balance. The purpose of the present study was to investigate the effectiveness of the Nintendo Wii Fit Plus exercises for improving balance ability in healthy collegiate students in comparison with a typical balance training program. Forty students were randomly divided into two groups, a traditional (T group) and a Nintendo Wii group (W group) performed an 8 week balance program. The "W group" used the interactive games as a training method, while the "T group" used an exercise program with mini trampoline and inflatable discs (BOSU). Pre and Post-training participants completed balance assessments. Two-way repeated measures analyses of variance (ANOVAs) were conducted to determine the effect of training program. Analysis of the data illustrated that both training program groups demonstrated an improvement in Total, Anterior-posterior and Medial Lateral Stability Index scores for both limbs. Only at the test performed in the balance board with anterior-posterior motion, the improvement in balance ability was greater in the "T group" than the "W group", when the assessment was performed post-training (p=0.023). Findings support the effectiveness of using the Nintendo Wii gaming console as a balance training intervention tool.

Fibromyalgia is Associated with Impaired Balance and Falls

Science.gov (United States)

Jones, Kim D.; Horak, Fay B.; Winters, Kerri Stone; Morea, Jessica M.; Bennett, Robert M.

2010-01-01

Background/Objective The purpose of this study was to determine whether FM patients differ from matched healthy controls in clinical tests of balance ability and fall frequency. Methods 34 FM patients and 32 age matched controls were administered the Balance Evaluation-Systems Test (BESTest), rated their balance confidence with the Activities-Specific Balance Confidence Scale (ABC) and reported the number of falls in the last 6 months. The Fibromyalgia Impact Questionnaire (FIQ) was used to assess FM severity. Results FM patients had significantly impaired balance in all components of the BESTest compared to controls. They also scored more poorly on balance confidence. Overall fibromyalgia severity (FIQ) correlated significantly with the BESTest, and the ABC scale. The BESTest and ABC correlated significantly with 6 commonly reported FM symptoms (excluding pain). FM patients reported a total of 37 falls over the last six-months compared to 6 falls in healthy controls. Conclusion Fibromyalgia is associated with balance problems and increased fall frequency. Patients were aware of their balance problems. These results suggest that FM may affect peripheral and/or central mechanisms of postural control. Further objective study is needed to identify the relative contributions of neural and musculoskeletal impairments to postural stability in FM, thus providing clinicians with exercise prescriptions that maximize postural stability. PMID:19125137

Market risks and oilfield ownership - Refining oil and gas disclosures

International Nuclear Information System (INIS)

Kretzschmar, Gavin L.; Hatherly, David; Misund, Bard

2007-01-01

Market risk exposures of balance sheet asset values are becoming an increasingly important accounting issue. In oil and gas, oilfield exposures to oil prices are specific and contractual, presenting a contingency problem for investors, financial analysts, standard setting bodies and government agencies. Our paper uses an extensive sample of 292 oilfields to provide evidence that the US Securities and Exchange Commission (SEC) supplementary disclosures do not capture the price sensitivities of oil and gas disclosures implicit in the two main forms of oilfield ownership, concession and production sharing contracts (PSCs). Current asset disclosures neither distinguish between global variations in oilfield ownership terms, nor on market risk implications for the value of oilfield assets. Importantly, we show that unlike concessions, reserve and production disclosures vary in response to oil price movements for PSC regimes. Our results highlight the need to differentiate PSC disclosures from concession fields, and to fully reflect price risks implicit in oilfield ownership contracts. We extend findings by Rajgopal [1999. Early evidence on the informativeness of the SEC's market risk disclosures: the case of commodity price risk exposure of oil and gas producers. The Accounting Review 74, 251-280] and propose refinements to capture market risk in financial reporting. (author)

Balanced and sparse Tamo-Barg codes

KAUST Repository

Halbawi, Wael; Duursma, Iwan; Dau, Hoang; Hassibi, Babak

2017-01-01

We construct balanced and sparse generator matrices for Tamo and Barg's Locally Recoverable Codes (LRCs). More specifically, for a cyclic Tamo-Barg code of length n, dimension k and locality r, we show how to deterministically construct a generator matrix where the number of nonzeros in any two columns differs by at most one, and where the weight of every row is d + r - 1, where d is the minimum distance of the code. Since LRCs are designed mainly for distributed storage systems, the results presented in this work provide a computationally balanced and efficient encoding scheme for these codes. The balanced property ensures that the computational effort exerted by any storage node is essentially the same, whilst the sparse property ensures that this effort is minimal. The work presented in this paper extends a similar result previously established for Reed-Solomon (RS) codes, where it is now known that any cyclic RS code possesses a generator matrix that is balanced as described, but is sparsest, meaning that each row has d nonzeros.

Balanced and sparse Tamo-Barg codes

KAUST Repository

Halbawi, Wael

2017-08-29

We construct balanced and sparse generator matrices for Tamo and Barg\\'s Locally Recoverable Codes (LRCs). More specifically, for a cyclic Tamo-Barg code of length n, dimension k and locality r, we show how to deterministically construct a generator matrix where the number of nonzeros in any two columns differs by at most one, and where the weight of every row is d + r - 1, where d is the minimum distance of the code. Since LRCs are designed mainly for distributed storage systems, the results presented in this work provide a computationally balanced and efficient encoding scheme for these codes. The balanced property ensures that the computational effort exerted by any storage node is essentially the same, whilst the sparse property ensures that this effort is minimal. The work presented in this paper extends a similar result previously established for Reed-Solomon (RS) codes, where it is now known that any cyclic RS code possesses a generator matrix that is balanced as described, but is sparsest, meaning that each row has d nonzeros.

Work and life balance of female doctors in the Czech Republic

OpenAIRE

Bočková, Šárka

2014-01-01

This bachelor thesis focuses on work and life balance of female doctors in the Czech Republic. Conflicting requirements of labour market, traditional division of gender roles, lack of institutional support for parents (insufficient number of establishment providing child care et.) and specific demands of being doctor complicate work and life balance. In the theoretical part were discussed key theories based on personal freedom of choices or structural barriers of labour market, specifics of m...

Accelerated production of antigen-specific T-cells for pre-clinical and clinical applications using Gas-permeable Rapid Expansion cultureware (G-Rex)

Science.gov (United States)

Vera, Juan F.; Brenner, Lara J.; Gerdemann, Ulrike; Ngo, Minhtran C.; Sili, Uluhan; Liu, Hao; Wilson, John; Dotti, Gianpietro; Heslop, Helen E.; Leen, Ann M.; Rooney, Cliona M.

2009-01-01

The clinical manufacture of antigen-specific cytotoxic T lymphocytes (CTL) for adoptive immunotherapy is limited by the complexity and time required to produce large numbers with the desired function and specificity. The culture conditions required are rigorous, and in some cases only achieved in 2cm2 wells in which cell growth is limited by gas exchange, nutrients and waste accumulation. Bioreactors developed to overcome these issues tend to be complex, expensive and not always conducive to CTL growth. We observed that antigen-specific CTL undergo seven to ten divisions post-stimulation. However the expected CTL numbers were achieved only in the first week of culture. By recreating the culture conditions present during this first week - low frequency of antigen-specific T-cells and high frequency of feeder cells - we were able to increase CTL expansion to expected levels which could be sustained for several weeks without affecting phenotype or function. However, the number of 24-well plates needed was excessive and cultures required frequent media changes, increasing complexity and manufacturing costs. Therefore, we evaluated novel gas-permeable culture devices (G-Rex) with a silicone membrane at the base allowing gas exchange to occur uninhibited by depth of medium above. This system effectively supports the expansion of CTL and actually increases output by up to 20-fold while decreasing required technician time. Importantly, this amplified cell expansion is not due to more cell divisions but to reduced cell death. This bioprocess optimization increased T-cell output while decreasing the complexity and cost of CTL manufacture, making cell therapy more accessible. PMID:20445351

The balance space approach to multicriteria decision making—involving the decision maker

OpenAIRE

Ehrgott, M.

2002-01-01

The balance space approach (introduced by Galperin in 1990) provides a new view on multicriteria optimization. Looking at deviations from global optimality of the different objectives, balance points and balance numbers are defined when either different or equal deviations for each objective are allowed. Apportioned balance numbers allow the specification of proportions among the deviations. Through this concept the decision maker can be involved in the decision process. In this paper we prov...

Balance Problems

Science.gov (United States)

... fully trust your sense of balance. Loss of balance also raises the risk of falls. This is a serious and even life-threatening ... 65. Balance disorders are serious because of the risk of falls. But occasionally balance problems may warn of another health condition, such ...

Selectivity and sparseness in randomly connected balanced networks.

Directory of Open Access Journals (Sweden)

Cengiz Pehlevan

Full Text Available Neurons in sensory cortex show stimulus selectivity and sparse population response, even in cases where no strong functionally specific structure in connectivity can be detected. This raises the question whether selectivity and sparseness can be generated and maintained in randomly connected networks. We consider a recurrent network of excitatory and inhibitory spiking neurons with random connectivity, driven by random projections from an input layer of stimulus selective neurons. In this architecture, the stimulus-to-stimulus and neuron-to-neuron modulation of total synaptic input is weak compared to the mean input. Surprisingly, we show that in the balanced state the network can still support high stimulus selectivity and sparse population response. In the balanced state, strong synapses amplify the variation in synaptic input and recurrent inhibition cancels the mean. Functional specificity in connectivity emerges due to the inhomogeneity caused by the generative statistical rule used to build the network. We further elucidate the mechanism behind and evaluate the effects of model parameters on population sparseness and stimulus selectivity. Network response to mixtures of stimuli is investigated. It is shown that a balanced state with unselective inhibition can be achieved with densely connected input to inhibitory population. Balanced networks exhibit the "paradoxical" effect: an increase in excitatory drive to inhibition leads to decreased inhibitory population firing rate. We compare and contrast selectivity and sparseness generated by the balanced network to randomly connected unbalanced networks. Finally, we discuss our results in light of experiments.

Visual feedback training using WII Fit improves balance in Parkinson's disease.

Science.gov (United States)

Zalecki, Tomasz; Gorecka-Mazur, Agnieszka; Pietraszko, Wojciech; Surowka, Artur D; Novak, Pawel; Moskala, Marek; Krygowska-Wajs, Anna

2013-01-01

Postural instability including imbalance is the most disabling long term problem in Parkinson's disease (PD) that does not respond to pharmacotherapy. This study aimed at investigating the effectiveness of a novel visual-feedback training method, using Wii Fit balance board in improving balance in patients with PD. Twenty four patients with moderate PD were included in the study which comprised of a 6-week home-based balance training program using Nintendo Wii Fit and balance board. The PD patients significantly improved their results in Berg Balance Scale, Tinnet's Performance-Oriented Mobility Assessment, Timed Up-and-Go, Sit-to-stand test, 10-Meter Walk test and Activities-specific Balance Confidence scale at the end of the programme. This study suggests that visual feedback training using Wii-Fit with balance board could improve dynamic and functional balance as well as motor disability in PD patients.

Natural gas information 2004. With 2003 data

International Nuclear Information System (INIS)

2004-01-01

A detailed reference work on gas supply and demand covering not only the OECD countries but also the rest of the world, this publication contains essential information on LNG and pipeline trade, gas reserves, storage capacity and prices. The main part of the book concentrates on OECD countries, showing a detailed supply and demand balance for each country and for the three OECD regions: North America, Europe and Pacific, as well as a breakdown of gas consumption by end-user. Import and export data are reported by source and destination. The CD-Rom and on-line service contain detailed time series from 1960 (1971 for some countries) to 2003. End-use data are available up to 2002

The Asia Pacific gas market: a question of balance

International Nuclear Information System (INIS)

Russell Jacobs

1997-01-01

The underlying need for additional supplies of natural gas, both and pipeline and LNG , will be continue to expand in the Asia Pacific region. Spurred by expected development of LNG markets in Thailand,India,and coastal China, the demand for LNG could more than double by 2010. To meet the LNG needs of the future, numerous LNG grass roots and expansion projects are underway or firmly planned. Collectively , these projects could supply nearly million tonnes of additional LNG by 2005-2010. If new geographical markets can not be developed (for whatever reasons) during this time frame, however, some currently planned projects could falter or be under utilized. (Author) 3 figs

The Asia Pacific gas market: a question of balance

Energy Technology Data Exchange (ETDEWEB)

Jacobs, Russell [Purvin and Gertz, Inc., Dallas, TX (United States)

1997-06-01

The underlying need for additional supplies of natural gas, both and pipeline and LNG , will be continue to expand in the Asia Pacific region. Spurred by expected development of LNG markets in Thailand,India,and coastal China, the demand for LNG could more than double by 2010. To meet the LNG needs of the future, numerous LNG grass roots and expansion projects are underway or firmly planned. Collectively , these projects could supply nearly million tonnes of additional LNG by 2005-2010. If new geographical markets can not be developed (for whatever reasons) during this time frame, however, some currently planned projects could falter or be under utilized. (Author) 3 figs.

Energy Balances of OECD Countries 2013 Edition

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-01

This volume contains data on the supply and consumption of coal, oil, gas, electricity, heat, renewables and waste presented as comprehensive energy balances expressed in million tonnes of oil equivalent. Complete data are available for 2010 and 2011 and supply estimates are available for the most recent year (i.e.2012). Historical tables summarise production, trade and final consumption data as well as key energy and economic indicators. The book also includes definitions of products and flows, explanatory notes on the individual country data and conversion factors from original units to energy units.

Efficient simulation of gas-liquid pipe flows using a generalized population balance equation coupled with the algebraic slip model

KAUST Repository

Icardi, Matteo; Ronco, Gianni; Marchisio, Daniele Luca; Labois, Mathieu

2014-01-01

The inhomogeneous generalized population balance equation, which is discretized with the direct quadrature method of moment (DQMOM), is solved to predict the bubble size distribution (BSD) in a vertical pipe flow. The proposed model is compared with a more classical approach where bubbles are characterized with a constant mean size. The turbulent two-phase flow field, which is modeled using a Reynolds-Averaged Navier-Stokes equation approach, is assumed to be in local equilibrium, thus the relative gas and liquid (slip) velocities can be calculated with the algebraic slip model, thereby accounting for the drag, lift, and lubrication forces. The complex relationship between the bubble size distribution and the resulting forces is described accurately by the DQMOM. Each quadrature node and weight represents a class of bubbles with characteristic size and number density, which change dynamically in time and space to preserve the first moments of the BSD. The predictions obtained are validated against previously published experimental data, thereby demonstrating the advantages of this approach for large-scale systems as well as suggesting future extensions to long piping systems and more complex geometries. © 2014 Elsevier Inc.

Efficient simulation of gas-liquid pipe flows using a generalized population balance equation coupled with the algebraic slip model

KAUST Repository

Icardi, Matteo

2014-09-01

The inhomogeneous generalized population balance equation, which is discretized with the direct quadrature method of moment (DQMOM), is solved to predict the bubble size distribution (BSD) in a vertical pipe flow. The proposed model is compared with a more classical approach where bubbles are characterized with a constant mean size. The turbulent two-phase flow field, which is modeled using a Reynolds-Averaged Navier-Stokes equation approach, is assumed to be in local equilibrium, thus the relative gas and liquid (slip) velocities can be calculated with the algebraic slip model, thereby accounting for the drag, lift, and lubrication forces. The complex relationship between the bubble size distribution and the resulting forces is described accurately by the DQMOM. Each quadrature node and weight represents a class of bubbles with characteristic size and number density, which change dynamically in time and space to preserve the first moments of the BSD. The predictions obtained are validated against previously published experimental data, thereby demonstrating the advantages of this approach for large-scale systems as well as suggesting future extensions to long piping systems and more complex geometries. © 2014 Elsevier Inc.

Effects of dynamic posturographic balance training versus conventional balance training on mobility and balance in elderly

International Nuclear Information System (INIS)

Saddiqi, F.A.; Masood, T.

2017-01-01

To determine the effects of dynamic posturographic balance training versus conventional balance training in improving mobility and balance in elderly. Methodology: Forty subjects between 50 to 80 years of age were selected via non-probability convenience sampling technique, for this randomized controlled trial. Both females and males with no major co-morbid conditions and cognitive impairments were recruited and randomized via coin toss method into two equal groups: Dynamic Posturographic balance training (DPG) group and Conventional balance training (CBT) group. The DPG training was provided via Biodex Balance System (Static and Dynamic). Both groups received interventions 3 times (35 to 45min each day) a week for 8 weeks, after which terminal assessment was done. Data were collected on demographic profile, balance via berg balance score and mobility by using Timed Up and Go Test. Independent samples t test was used to check difference between CBT group and DPG Group and repeated measures Analysis of Variance (ANOVA) was used for within-group analysis. Results: Baseline analysis of Berg balance scale and timed up and go test between two groups showed no significant difference with (p 0.805 and 0.251, respectively). After 8 weeks of intervention, there was significant difference between the groups in both variables (p 0.019 and 0.001, respectively). Conclusion: Dynamic posturographic balance training was more effective in improving dynamic balance and mobility in elderly population in comparison to conventional balance training. (author)

Influence of the nitrogen gas addition in the Ar shielding gas on the erosion-corrosion of tube-to-tube sheet welds of hyper duplex stainless steel

International Nuclear Information System (INIS)

Kim, Hye-Jin; Jeon, Soon-Hyeok; Kim, Soon-Tae; Lee, In-Sung; Park, Yong-Soo

2014-01-01

Duplex stainless steels with nearly equal fraction of the ferrite(α) phase and austenite(γ) phase have been increasingly used for various applications such as power plants, desalination facilities due to their high resistance to corrosion, good weldability, and excellent mechanical properties. Hyper duplex stainless steel (HDSS) is defined as the future duplex stainless steel with a pitting resistance equivalent (PRE= wt.%Cr+3.3(wt.%Mo+0.5wt.%W)+30wt.%N) of above 50. However, when HDSS is welded with gas tungsten arc (GTA), incorporation of nitrogen in the Ar shielding gas are very important because the volume fraction of α-phase and γ-phase is changed and harmful secondary phases can be formed in the welded zone. In other words, the balance of corrosion resistance between two phases and reduction of Cr 2 N are the key points of this study. The primary results of this study are as follows. The addition of N 2 to the Ar shielding gas provides phase balance under weld-cooling conditions and increases the transformation temperature of the α-phase to γ-phase, increasing the fraction of γ-phase as well as decreasing the precipitation of Cr2N. In the anodic polarization test, the addition of nitrogen gas in the Ar shielding gas improved values of the electrochemical parameters, compared to the Pure Ar. Also, in the erosion-corrosion test, the HDSS welded with shielding gas containing N 2 decreased the weight loss, compared to HDSS welded with the Ar pure gas. This result showed the resistance of erosion-corrosion was increased due to increasing the fraction of γ-phase and the stability of passive film according to the addition N 2 gas to the Ar shielding gas. As a result, the addition of nitrogen gas to the shielding gas improved the resistance of erosion-corrosion

Influence of the nitrogen gas addition in the Ar shielding gas on the erosion-corrosion of tube-to-tube sheet welds of hyper duplex stainless steel

Energy Technology Data Exchange (ETDEWEB)

Kim, Hye-Jin; Jeon, Soon-Hyeok; Kim, Soon-Tae; Lee, In-Sung; Park, Yong-Soo [Yonsei University, Seoul (Korea, Republic of)

2014-03-15

Duplex stainless steels with nearly equal fraction of the ferrite(α) phase and austenite(γ) phase have been increasingly used for various applications such as power plants, desalination facilities due to their high resistance to corrosion, good weldability, and excellent mechanical properties. Hyper duplex stainless steel (HDSS) is defined as the future duplex stainless steel with a pitting resistance equivalent (PRE= wt.%Cr+3.3(wt.%Mo+0.5wt.%W)+30wt.%N) of above 50. However, when HDSS is welded with gas tungsten arc (GTA), incorporation of nitrogen in the Ar shielding gas are very important because the volume fraction of α-phase and γ-phase is changed and harmful secondary phases can be formed in the welded zone. In other words, the balance of corrosion resistance between two phases and reduction of Cr{sub 2}N are the key points of this study. The primary results of this study are as follows. The addition of N{sub 2} to the Ar shielding gas provides phase balance under weld-cooling conditions and increases the transformation temperature of the α-phase to γ-phase, increasing the fraction of γ-phase as well as decreasing the precipitation of Cr2N. In the anodic polarization test, the addition of nitrogen gas in the Ar shielding gas improved values of the electrochemical parameters, compared to the Pure Ar. Also, in the erosion-corrosion test, the HDSS welded with shielding gas containing N{sub 2} decreased the weight loss, compared to HDSS welded with the Ar pure gas. This result showed the resistance of erosion-corrosion was increased due to increasing the fraction of γ-phase and the stability of passive film according to the addition N{sub 2} gas to the Ar shielding gas. As a result, the addition of nitrogen gas to the shielding gas improved the resistance of erosion-corrosion.

Assessing ecological sustainability in urban planning - EcoBalance model

Energy Technology Data Exchange (ETDEWEB)

Wahlgren, I., Email: irmeli.wahlgren@vtt.fi

2012-06-15

Urban planning solutions and decisions have large-scale significance for ecological sustainability (eco-efficiency) the consumption of energy and other natural resources, the production of greenhouse gas and other emissions and the costs caused by urban form. Climate change brings new and growing challenges for urban planning. The EcoBalance model was developed to assess the sustainability of urban form and has been applied at various planning levels: regional plans, local master plans and detailed plans. The EcoBalance model estimates the total consumption of energy and other natural resources, the production of emissions and wastes and the costs caused directly and indirectly by urban form on a life cycle basis. The results of the case studies provide information about the ecological impacts of various solutions in urban development. (orig.)

Technologies applied to wells producing gas in Bolivia; Tecnologias aplicadas aos pocos produtores de gas em Bolivia

Energy Technology Data Exchange (ETDEWEB)

Nobrega, Fernando R.B. [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil); Carrillo, Marco A.; Barrerro, Dennys A. [PETROBRAS Bolivia S.A., La Paz (Bolivia)

2012-07-01

The This paper seeks to highlight the engineering, lessons learned and topics for improvement of the technologies used in gas wells drilled between November 2008 and October 2011 in an environment of Bolivian' subandino. Among technologies employed and commented hereunder has the drilling gas reservoirs in near balance using a dual phase fluid, with nitrogen; carrying out multilateral wells equipped with intelligent completion in such environment; as well as other technologies presented herein. This document was prepared on drilling operations performed in SAL-15, SAL-17, SBLSBL- 7 and SBL-8, comprising the period from November 2008 to October 2011. (author)

Founders Energy Ltd. 1998 annual report : fiscally prudent, value driven balanced growth strategy

International Nuclear Information System (INIS)

1999-01-01

Founders Energy Ltd is a growth-oriented junior resource company engaged in the acquisition and development of oil and natural gas properties in Alberta, British Columbia and Saskatchewan. The annual review provides details of the company's operations and relevant financial performance during the 1998 fiscal year. In brief, the company realized significant increases in production and reserves, top quartile findings and development costs. It reported significant increases in leverage to natural gas through exploration success at Pouce Coupe and the acquisition of Opal Energy Inc.. It established new core areas in west-central Alberta, Peace River Arch and west-central Saskatchewan. It achieved a better balanced risk profile through geographical diversification and better balance to exploration and development. It increased undeveloped land area to 160,268 net acres and added 11.5 million barrels of established reserves at a finding cost of $ 6.28 per barrel. Financial highlights include increased gross revenue, increased net income per share, and increased shareholders' equity. tabs., figs

The Effects of a Postural Balance Training Program on Balance, Gait and Health-Related Quality of Life in Patients with Essential Tremor

Directory of Open Access Journals (Sweden)

Bilge Kara

2018-03-01

Full Text Available Objective: Although the effectiveness of postural balance training on balance and gait impairment has been proven as an effective treatment approach in several patient and healthy populations, its effectiveness in patients with essential tremor (ET is yet unknown. The aim was to examine the effects of postural balance training program on balance and gait performance, and health-related quality of life in patients with ET. Materials and Methods: This uncontrolled clinical study included patients with ET. The outcome measures were the Postural Stability Test, Limits of Stability Test, Fall Risk Test, Activities-Specific Balance Confidence scale, Dynamic Gait Index, and Short Form-36. The assessments were performed before and after the training program. The participants underwent an 8-week balance training designed to improve their ability to integrate multisensory inputs and postural control using a computerized balance assessment and training device. Results: In total, 24 patients with ET participated in the study. The compliance rate was 87.5%. There were significant improvements in all outcome measures of balance and gait performance, balance confidence, fall risk, and health-related quality of life (except the mental component, p>0.05 between baseline and 8 weeks (p<0.05. Conclusion: Our results suggest that the balance training program is a feasible method that may have positive effects on balance performance and confidence, gait performance, and health-related quality of life in patients with ET

Modelling isothermal fission gas release

International Nuclear Information System (INIS)

Uffelen, P. van

2002-01-01

The present paper presents a new fission gas release model consisting of two coupled modules. The first module treats the behaviour of the fission gas atoms in spherical grains with a distribution of grain sizes. This module considers single atom diffusion, trapping and fission induced re-solution of gas atoms associated with intragranular bubbles, and re-solution from the grain boundary into a few layers adjacent to the grain face. The second module considers the transport of the fission gas atoms along the grain boundaries. Four mechanisms are incorporated: diffusion controlled precipitation of gas atoms into bubbles, grain boundary bubble sweeping, re-solution of gas atoms into the adjacent grains and gas flow through open porosity when grain boundary bubbles are interconnected. The interconnection of the intergranular bubbles is affected both by the fraction of the grain face occupied by the cavities and by the balance between the bubble internal pressure and the hydrostatic pressure surrounding the bubbles. The model is under validation. In a first step, some numerical routines have been tested by means of analytic solutions. In a second step, the fission gas release model has been coupled with the FTEMP2 code of the Halden Reactor Project for the temperature distribution in the pellets. A parametric study of some steady-state irradiations and one power ramp have been simulated successfully. In particular, the Halden threshold for fission gas release and two simplified FUMEX cases have been computed and are summarised. (author)

Emission characterization and evaluation of natural gas-fueled cogeneration microturbines and internal combustion engines

International Nuclear Information System (INIS)

Canova, Aldo; Chicco, Gianfranco; Genon, Giuseppe; Mancarella, Pierluigi

2008-01-01

The increasing diffusion of small-scale energy systems within the distributed generation (DG) paradigm is raising the need for studying the environmental impact due to the different DG solutions in order to assess their sustainability. Addressing the environmental impact calls for building specific models for studying both local and global emissions. In this framework, the adoption of natural gas-fueled DG cogeneration technologies may provide, as a consequence of cogeneration enhanced overall energy efficiency and of natural gas relatively low carbon content, a significant reduction of global impact in terms of CO 2 emissions with respect to the separate production of electricity and heat. However, a comprehensive evaluation of the DG alternatives should take into account as well the impact due to the presence of plants spread over the territory that could increase the local pollution, in particular due to CO and NO x , and thus could worsen the local air quality. This paper provides an overview on the characterization of the emissions from small-scale natural gas-fueled cogeneration systems, with specific reference to the DG technologies nowadays most available in the market, namely, microturbines and internal combustion engines. The corresponding local and global environmental impacts are evaluated by using the emission balance approach. A numerical case study with two representative machines highlights their different emission characteristics, also considering the partial-load emission performance

Device for measurement of gas mass flow. Einrichtung zur Gasmassenstrommessung

Energy Technology Data Exchange (ETDEWEB)

Sass, W

1989-09-28

The invention is concerned with a device for the measurement of gas mass flow, particularly measuring air mass flow for vehicles with internal combustion engines, with a measurement bridge, in one branch of which a gas flow resistance, particularly a hot film sensor, with gas flowing round it, is connected in series with a measurement resistance and in another branch of which a compensation resistance measuring the gas temperature is connected in series with a fixed resistor, where the bridge differential voltage is measured in the zero branch of the measuring bridge and a control parameter is produced from this, in order to control a transistor valve situated in the bridge supply path of a DC voltage source via its control electrode until the bridge is balanced, and where the voltage at the measurement resistance after the bridge is balanced is used as a measure of the gas mass flow. In order to obtain exact results of measurement in spite of relatively high interference noise from the cables, it is proposed that an increased supply DC voltage appreciably decreasing the occurring interference noise from the cables should be produced from a small DC voltage and that the output of the DC/DC voltage converter should be connected to the control electrode of the transistor valve, so that the control parameter for the control electrode is derived from the raised DC supply voltage through reducers depending on the gas flow.

Interchangeability of the Wii Balance Board for Bipedal Balance Assessment.

Science.gov (United States)

Bonnechère, Bruno; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

2015-08-27

Since 2010, an increasing interest in more portable and flexible hardware for balance and posture assessment led to previously published studies determining whether or not the Wii Balance Board could be used to assess balance and posture, both scientifically and clinically. However, no previous studies aimed at comparing results from different Wii Balance Boards for clinical balance evaluation exist. The objective of this crossover study is to assess the interchangeability of the Wii Balance Board. A total of 6 subjects participated in the study and their balance was assessed using 4 different Wii Balance Boards. Trials were recorded simultaneously with Wii Balance Boards and with a laboratory force plate. Nine relevant clinical parameters were derived from center of pressure displacement data obtained from Wii Balance Board and force plate systems. Intraclass correlation coefficients (ICC), F tests, and Friedman tests were computed to assess the agreement between trials and to compare the Wii Balance Board and force plate results. Excellent correlations were found between the Wii Balance Board and force plate (mean ρ =.83). With the exception of 2 parameters, strong to excellent agreements were found for the 7 remaining parameters (ICC=.96). No significant differences were found between trials recorded with different Wii Balance Boards. Our results indicate that for most of the parameters analyzed, balance and posture assessed with one Wii Balance Board were statistically similar to results obtained from another. Furthermore, the good correlation between the Wii Balance Board and force plate results shows that Wii Balance Boards can be reliably used for scientific assessment using most of the parameters analyzed in this study. These results also suggest that the Wii Balance Board could be used in multicenter studies and therefore, would allow for the creation of larger populations for clinical studies. Ethical Committee of the Erasme Hospital (CCB B406201215142

Gas mission; Mission gaz

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This preliminary report analyses the desirable evolutions of gas transport tariffing and examines some questions relative to the opening of competition on the French gas market. The report is made of two documents: a synthesis of the previous report with some recommendations about the tariffing of gas transport, about the modalities of network access to third parties, and about the dissociation between transport and trade book-keeping activities. The second document is the progress report about the opening of the French gas market. The first part presents the European problem of competition in the gas supply and its consequences on the opening and operation of the French gas market. The second part presents some partial syntheses about each topic of the mission letter of the Ministry of Economics, Finances and Industry: future evolution of network access tariffs, critical analysis of contractual documents for gas transport and delivery, examination of auxiliary services linked with the access to the network (modulation, balancing, conversion), consideration about the processing of network congestions and denied accesses, analysis of the metering dissociation between the integrated activities of gas operators. Some documents are attached in appendixes: the mission letter from July 9, 2001, the detailed analysis of the new temporary tariffs of GdF and CFM, the offer of methane terminals access to third parties, the compatibility of a nodal tariffing with the presence of three transport operators (GdF, CFM and GSO), the contract-type for GdF supply, and the contract-type for GdF connection. (J.S.)

Analyzer for measuring gas contained in the pore space of rocks

Science.gov (United States)

Kudasik, Mateusz; Skoczylas, Norbert

2017-10-01

In the present paper, the authors discussed the functioning of their own analyzer for measuring gas contained in the pore space of high strength rocks. A sample is placed inside a hermetic measuring chamber, and then undergoes impact milling as a result of colliding with the vibrating blade of a knife which is rotationally driven by a high-speed brushless electric motor. The measuring chamber is equipped with all the necessary sensors, i.e. gas, pressure, and temperature sensors. Trial tests involving the comminution of dolomite and anhydrite samples demonstrated that the constructed device is able to break up rocks into grains so fine that they are measured in single microns, and the sensors used in the construction ensure balancing of the released gas. The tests of the analyzer showed that the metrological concept behind it, together with the way it was built, make it fit for measurements of the content and composition of selected gases from the rock pore space. On the basis of the conducted tests of balancing the gases contained in the two samples, it was stated that the gas content of Sample no. 1 was (0.055  ±  0.002) cm3 g-1, and Sample no. 2 contained gas at atmospheric pressure, composed mostly of air.

Tailoring Psychosocial Risk Assessment in the Oil and Gas Industry by Exploring Specific and Common Psychosocial Risks

Directory of Open Access Journals (Sweden)

Linn Iren Vestly Bergh

2018-03-01

Full Text Available Background: Psychosocial risk management [Psychosocial Risk Management Approach (PRIMA] has, through the years, been applied in several organizations in various industries and countries globally. PRIMA principles have also been translated into international frameworks, such as PRIMA-EF (European framework and the World Health Organization Healthy Workplace Framework. Over the past 10 years, an oil and gas company has put efforts into adopting and implementing international frameworks and standards for psychosocial risk management. More specifically, the company uses a PRIMA. Methods: This study explores available quantitative and qualitative risk data collected through the PRIMA method over the past 8 years in order to explore specific and common psychosocial risks in the petroleum industry. Results: The analyses showed a significant correlation between job resources and symptoms of work-related stress, there was a significant correlation between job demands and symptoms of work-related stress, and there were differences in psychosocial risk factors and symptoms of work-related stress onshore and offshore. The study also offers recommendations on how the results can further be utilized in building a robust system for managing psychosocial risks in the industry. Conclusion: The results from the analyses have provided meaningful and important information about the company-specific psychosocial risk factors and their impact on health and well-being. Keywords: oil and gas industry, psychosocial risk factors, psychosocial risk management

Modeling the Phase Composition of Gas Condensate in Pipelines

Science.gov (United States)

Dudin, S. M.; Zemenkov, Yu D.; Shabarov, A. B.

2016-10-01

Gas condensate fields demonstrate a number of thermodynamic characteristics to be considered when they are developed, as well as when gas condensate is transported and processed. A complicated phase behavior of the gas condensate system, as well as the dependence of the extracted raw materials on the phase state of the deposit other conditions being equal, is a key aspect. Therefore, when designing gas condensate lines the crucial task is to select the most appropriate methods of calculating thermophysical properties and phase equilibrium of the transported gas condensate. The paper describes a physical-mathematical model of a gas-liquid flow in the gas condensate line. It was developed based on balance equations of conservation of mass, impulse and energy of the transported medium within the framework of a quasi-1D approach. Constitutive relationships are given separately, and practical recommendations on how to apply the research results are provided as well.

Chance for balance: Chance for balance

OpenAIRE

Sævild, Katariina; Skov Sørensen, Katrine; Kildahl Lauritsen, Louise; Fuglsang, Sofie Olivia; Arnbjerg, Stine Høegh

2015-01-01

This project investigates how (im) balance between family and career influences Danish women's desire to have children. In order to answer this question, we have chosen to use qualitative method and our analysis is based on two semi-structured research interviews with two chosen women. Thus these women’s definition of balance and their view on children define the project. We have chosen to use of work-life balance theories, Thomas Hoejrup’s lifeform-analysis and Anthony Giddens’ theories of s...

Balanced truncation for linear switched systems

DEFF Research Database (Denmark)

Petreczky, Mihaly; Wisniewski, Rafal; Leth, John-Josef

2013-01-01

In this paper, we present a theoretical analysis of the model reduction algorithm for linear switched systems from Shaker and Wisniewski (2011, 2009) and . This algorithm is a reminiscence of the balanced truncation method for linear parameter varying systems (Wood et al., 1996) [3]. Specifically...

Gas chromatographic quantitative analysis of the gaseous emissions and carbon balance in the alcoholic fermentation

Directory of Open Access Journals (Sweden)

C. Chon

1997-06-01

ln order to try to answer to this question, methods able to analyse simultaneously and quantitatively the liquid phase, the gaseous emissions and the biomass are needed. Recently, we have shown that under suitable defined conditions 13C NMR spectroscopy allows the quantitative measurement of at least eight components present at a concentration up to 5 x 10-3M (glycerol, glucose, butandiols, tartric, malic, lactic, citric and succinic acids in a short time (one hour with a precision of about 3 p. cent. The measurements of the ethanol concentrations and of the amount of carbon transferred in the biomass are easily achieved using respectively ebullioscopic and standard combustion techniques. We are now able to extend these results and to show that, by using gas chromatography in a continuous dynamic mode and under a sweep of air at the head space of the fermentor, it is possible to measure quantitatively the mixture of volatile substances (composed mainly of air, carbon dioxide, ethanol and water emanating from an alcoholic fermentation. The results obtained, when correlated with quantitative 13C NMR spectroscopy on the medium components permits the total balance sheet of the carbon transfers occuring during the fermentation process betwcen the liquid and the gaseous phases to be established. Our results indicate that the losses of ethanol during the fermentation process conducted under an air flow at the head space of the fermentor, may reach about 10 p. cent of the theoretical maximal amount of ethanol produced. The experiments presented here could explain the ethanol losses observed during some vinification processes conducted in open tanks.

The water balance questionnaire: design, reliability and validity of a questionnaire to evaluate water balance in the general population.

Science.gov (United States)

Malisova, Olga; Bountziouka, Vassiliki; Panagiotakos, Demosthenes B; Zampelas, Antonis; Kapsokefalou, Maria

2012-03-01

There is a need to develop a questionnaire as a research tool for the evaluation of water balance in the general population. The water balance questionnaire (WBQ) was designed to evaluate water intake from fluid and solid foods and drinking water, and water loss from urine, faeces and sweat at sedentary conditions and physical activity. For validation purposes, the WBQ was administrated in 40 apparently healthy participants aged 22-57 years (37.5% males). Hydration indices in urine (24 h volume, osmolality, specific gravity, pH, colour) were measured through established procedures. Furthermore, the questionnaire was administered twice to 175 subjects to evaluate its reliability. Kendall's τ-b and the Bland and Altman method were used to assess the questionnaire's validity and reliability. The proposed WBQ to assess water balance in healthy individuals was found to be valid and reliable, and it could thus be a useful tool in future projects that aim to evaluate water balance.

The energy balance within a bubble column evaporator

Science.gov (United States)

Fan, Chao; Shahid, Muhammad; Pashley, Richard M.

2018-05-01

Bubble column evaporator (BCE) systems have been studied and developed for many applications, such as thermal desalination, sterilization, evaporative cooling and controlled precipitation. The heat supplied from warm/hot dry bubbles is to vaporize the water in various salt solutions until the solution temperature reaches steady state, which was derived into the energy balance of the BCE. The energy balance and utilization involved in each BCE process form the fundamental theory of these applications. More importantly, it opened a new field for the thermodynamics study in the form of heat and vapor transfer in the bubbles. In this paper, the originally derived energy balance was reviewed on the basis of its physics in the BCE process and compared with new proposed energy balance equations in terms of obtained the enthalpy of vaporization (Δ H vap) values of salt solutions from BCE experiments. Based on the analysis of derivation and Δ H vap values comparison, it is demonstrated that the original balance equation has high accuracy and precision, within 2% over 19-55 °C using improved systems. Also, the experimental and theoretical techniques used for determining Δ H vap values of salt solutions were reviewed for the operation conditions and their accuracies compared to the literature data. The BCE method, as one of the most simple and accurate techniques, offers a novel way to determine Δ H vap values of salt solutions based on its energy balance equation, which had error less than 3%. The thermal energy required to heat the inlet gas, the energy used for water evaporation in the BCE and the energy conserved from water vapor condensation were estimated in an overall energy balance analysis. The good agreement observed between input and potential vapor condensation energy illustrates the efficiency of the BCE system. Typical energy consumption levels for thermal desalination for producing pure water using the BCE process was also analyzed for different inlet air

Gas-fueling studies in the PDX tokamak

International Nuclear Information System (INIS)

Dylla, H.F.; Blanchard, W.R.; Budny, R.; Fonck, R.J.; Owens, D.K.; Schmidt, G.L.

1982-08-01

The characteristics of gas-fueling of high power discharges in the PDX tokamak have been investigated using gas-flow, neutral pressure, plasma density, and Hα emission measurements. The efficiency of gas-fueling was measured for various plasma configurations by comparison of the measured gas-influx rates to the particle exhaust rates inferred from particle decay time measurements. We observe that the fueling efficiency decreases significantly with increasing plasma density as the ionization length for thermal neutrals becomes shorter than the width of the boundary plasma. Gas fueling rates required to maintain a given plasma density are considerably higher (by factors of 5 to 10) for diverted discharges compared to limiter discharges. This result is attributed to a lower effective recycling coefficient for diverted plasmas. We discuss the dependence of the particle balance on the following experimentally measured parameters: the particle containment time, system-pumping speed, and neutral pressure in the vicinity of the active pumps

Analysis of carbon dioxide emission of gas fuelled cogeneration plant

International Nuclear Information System (INIS)

Nordin, Adzuieen; Amin, M; Majid, A

2013-01-01

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 CO 2 to the environment. This study analyzes the amount of CO 2 emission by Universiti Teknologi Petronas gas fuelled cogeneration system using energy balance equations. The results indicate that the cogeneration system reduces the CO 2 emission to the environment by 60%. This finding could encourage the power plant owners to install heat recovery systems to their respective plants

Analysis of carbon dioxide emission of gas fuelled cogeneration plant

Science.gov (United States)

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

2013-12-01

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.

Gas migration from oil and gas fields and associated hazards

International Nuclear Information System (INIS)

Gurevich, A.E.; Endres, B.L.; Robertson Jr, J.O.; Chilingar, G.V.

1993-01-01

The migration of gas from oil and gas formations to the surface is a problem that greatly affects those surface areas where human activity exists. Underground gas storage facilities and oil fields have demonstrated a long history of gas migration problems. Experience has shown that the migration of gas to the surface creates a serious potential risk of explosion, fires, noxious odors and potential emissions of carcinogenic chemicals. These risks must be seriously examined for all oil and gas operations located in urban areas. This paper presents the mechanics of gas migration, paths of migration and a review of a few of the risks that should be considered when operating a gas facility in an urban area. The gas can migrate in a continuous or discontinuous stream through porous, water-filled media to the surface. The primary force in this migration of gas is the difference between specific weights of gas and water

Active bypass flow control for a seal in a gas turbine engine

Science.gov (United States)

Ebert, Todd A.; Kimmel, Keith D.

2017-03-14

An active bypass flow control system for controlling bypass compressed air based upon leakage flow of compressed air flowing past an outer balance seal between a stator and rotor of a first stage of a gas turbine in a gas turbine engine is disclosed. The active bypass flow control system is an adjustable system in which one or more metering devices may be used to control the flow of bypass compressed air as the flow of compressed air past the outer balance seal changes over time as the outer balance seal between the rim cavity and the cooling cavity wears In at least one embodiment, the metering device may include an annular ring having at least one metering orifice extending therethrough, whereby alignment of the metering orifice with the outlet may be adjustable to change a cross-sectional area of an opening of aligned portions of the outlet and the metering orifice.

Greenhouse-gas emissions from soils increased by earthworms

NARCIS (Netherlands)

Lubbers, I.M.; Groenigen, van K.J.; Fonte, S.J.; Six, J.; Brussaard, L.; Groenigen, van J.W.

2013-01-01

Earthworms play an essential part in determining the greenhouse-gas balance of soils worldwide, and their influence is expected to grow over the next decades. They are thought to stimulate carbon sequestration in soil aggregates, but also to increase emissions of the main greenhouse gases carbon

Sensory-Challenge Balance Exercises Improve Multisensory Reweighting in Fall-Prone Older Adults.

Science.gov (United States)

Allison, Leslie K; Kiemel, Tim; Jeka, John J

2018-04-01

Multisensory reweighting (MSR) deficits in older adults contribute to fall risk. Sensory-challenge balance exercises may have value for addressing the MSR deficits in fall-prone older adults. The purpose of this study was to examine the effect of sensory-challenge balance exercises on MSR and clinical balance measures in fall-prone older adults. We used a quasi-experimental, repeated-measures, within-subjects design. Older adults with a history of falls underwent an 8-week baseline (control) period. This was followed by an 8-week intervention period that included 16 sensory-challenge balance exercise sessions performed with computerized balance training equipment. Measurements, taken twice before and once after intervention, included laboratory measures of MSR (center of mass gain and phase, position, and velocity variability) and clinical tests (Activities-specific Balance Confidence Scale, Berg Balance Scale, Sensory Organization Test, Limits of Stability test, and lower extremity strength and range of motion). Twenty adults 70 years of age and older with a history of falls completed all 16 sessions. Significant improvements were observed in laboratory-based MSR measures of touch gain (P = 0.006) and phase (P = 0.05), Berg Balance Scale (P = 0.002), Sensory Organization Test (P = 0.002), Limits of Stability Test (P = 0.001), and lower extremity strength scores (P = 0.005). Mean values of vision gain increased more than those for touch gain, but did not reach significance. A balance exercise program specifically targeting multisensory integration mechanisms improved MSR, balance, and lower extremity strength in this mechanistic study. These valuable findings provide the scientific rationale for sensory-challenge balance exercise to improve perception of body position and motion in space and potential reduction in fall risk.

Finite Element Modeling of Adsorption Processes for Gas Separation and Purification

International Nuclear Information System (INIS)

Humble, Paul H.; Williams, Richard M.; Hayes, James C.

2009-01-01

Pacific Northwest National Laboratory (PNNL) has expertise in the design and fabrication of automated radioxenon collection systems for nuclear explosion monitoring. In developing new systems there is an ever present need to reduce size, power consumption and complexity. Most of these systems have used adsorption based techniques for gas collection and/or concentration and purification. These processes include pressure swing adsorption, vacuum swing adsorption, temperature swing adsorption, gas chromatography and hybrid processes that combine elements of these techniques. To better understand these processes, and help with the development of improved hardware, a finite element software package (COMSOL Multiphysics) has been used to develop complex models of these adsorption based operations. The partial differential equations used include a mass balance for each gas species and adsorbed species along with a convection conduction energy balance equation. These equations in conjunction with multicomponent temperature dependent isotherm models are capable of simulating separation processes ranging from complex multibed PSA processes, and multicomponent temperature programmed gas chromatography, to simple two component temperature swing adsorption. These numerical simulations have been a valuable tool for assessing the capability of proposed processes and optimizing hardware and process parameters.

Sex Differences in Balance Among Alpine Ski Racers: Cross-Sectional Age Comparisons.

Science.gov (United States)

Raschner, Christian; Hildebrandt, Carolin; Mohr, Johanna; Müller, Lisa

2017-12-01

Although balance is a key ability in the strength demands of alpine ski racing, affecting both performance and injury prevention, few studies have examined balance or related sex differences among still-maturing athletes. In this 10-year study, we investigated cross-sectional balance performances at different age periods of a representative sample of over 500 11-18-year-old elite skiers of both genders. Participants performed balance tests using the MFT S3-Check. Left-right and forward-backward movements were used to calculate sensory and symmetry balance scores, which were both incorporated into a stability score. Mann-Whitney U tests assessed gender-specific differences by age-group with a significance level set at p gender differences only on forward-backward measurements for 14-16-year-olds, with females showing better stability and sensory (but not symmetry) scores than males. Thus, gender interacted with age and maturation to influence balance ability in these participants. Additionally, these rare 10-year data support coaches in their training and talent development of maturing athletes by providing important sport-, age-, and gender-specific normative comparison data for individual trainees.

Neutral particle balance in GDT with fast titanium coating of the first wall

International Nuclear Information System (INIS)

Bagryansky, P.A.; Bender, E.D.; Ivanov, A.A.; Krahl, S.; Noack, K.; Karpushov, A.N.; Murakhtin, S.V.; Shikhovtsev, I.V.

1995-01-01

The GDT is an axisymmetric open trap with a high mirror ratio for confinement of a collisional plasma. The experimental program of the GDT was focused on the generation of plasma physics database necessary for a GDT-based neutron source. A distinct feature of both GDT and the GDT-based neutron source is that the Larmor radius of the fast sloshing ions is comparable to plasma radius. In this case, the sloshing ions can not be well shielded by the plasma halo from penetration of the neutral gas from periphery that results in high charge exchange losses. The plasma parameters are then very sensitive to gas pressure near the plasma boundary. To reduce the gas pressure to desured value during the beam heating, the authors have used arc-type evaporators developed at the Budker INP for fast titanium coating of the GDT first wall. If needed, the coating can be done a few seconds before each shot. They investigated the neutral particle balance in presence of NB-heating. The inverted magnetron gauges were used to study the temporal dependence of gas pressure inside the central cell. Pyroelectric bolometers were employed to measure the flux of charge exchange neutrals. Neutral particle balance has also been studied numerically by using a gas-transport code. The results of the investigations are the following: (1) sloshing ion lifetime was increased about 10 times compared to that without the coating of the first wall; and (2) wall recycling coefficient of the Ti-coated wall does not exceed 1 for 8 keV mean energy of the neutral hydrogen atoms striking the wall

Does Nintendo Wii Balance Board improve standing balance? A randomized controlled trial in children with cerebral palsy.

Science.gov (United States)

Gatica-Rojas, Valeska; Méndez-Rebolledo, Guillermo; Guzman-Muñoz, Eduardo; Soto-Poblete, Alex; Cartes-Velásquez, Ricardo; Elgueta-Cancino, Edith; Cofré Lizama, L Eduardo

2017-08-01

Evidence on the effect of systemic exercise programs to improve the standing balance with the Nintendo Wii system is very limited and its post-treatment effectiveness is unknown in cerebral palsy (CP) patients. Primary aim was to compare the effect of Nintendo Wii balance board (Wii-therapy) and standard physiotherapy (SPT), on the performance of standing balance in children and adolescents with CP. Secondary aim was to determine the post-treatment effectiveness of Wii-therapy and SPT. Two-arm, matched-pairs, parallel-groups, randomized, controlled clinical trial. Outpatient Rehabilitation Centre in the city of Talca. Patients with CP type spastic hemiplegia (SHE) and spastic diplegia (SDI), aged 7 to 14 years, and level I or II of GMFCS or GMFCS-ER. Were excluded patients with FSIQWii-therapy (SDI=7; SHE=9) or SPT intervention (SDI=7; SHE=9). In each group, patients received three sessions per week over a period of 6 weeks. Standing balance was assessed at baseline and every 2 weeks. Additionally, two follow-up assessments (4 additional weeks) were performed to determine post-treatment effectiveness. Standing balance was quantified on force platform obtaining the outcomes area of center-of-pressure (CoP) sway (CoPSway), standard deviation in the medial-lateral (SDML) and the anterior-posterior (SDAP) directions, and velocity in both directions (VML and VAP). Compared to SPT, Wii-therapy significantly reduced the CoPSway (P=0.02) and SDAP in the eyes-open condition (P=0.01). However, the effects wane after 2-4 weeks. Post-hoc analysis revealed that only SHE children benefited from Wii-therapy. Wii-therapy was better than SPT in improving standing balance in patients with CP, but improves the balance only in SHE patients. Also, Wii-therapy effectiveness waned 2-4 weeks after the end the intervention. A systematic exercise program like Wii-therapy using the Nintendo Wii Balance Board device can be considered to improves the standing balance in patients with CP

Comparison of traditional and recent approaches in the promotion of balance and strength in older adults.

Science.gov (United States)

Granacher, Urs; Muehlbauer, Thomas; Zahner, Lukas; Gollhofer, Albert; Kressig, Reto W

2011-05-01

Demographic change in industrialized countries produced an increase in the proportion of elderly people in our society, resulting in specific healthcare challenges. One such challenge is how to effectively deal with the increased risk of sustaining a fall and fall-related injuries in old age. Deficits in postural control and muscle strength represent important intrinsic fall risk factors. Thus, adequate training regimens need to be designed and applied that have the potential to reduce the rate of falling in older adults by countering these factors. Therefore, the purpose of this review is to compare traditional and recent approaches in the promotion of balance and strength in older adults. Traditionally, balance and resistance training programmes proved to be effective in improving balance and strength, and in reducing the number of falls. Yet, it was argued that these training protocols are not specific enough to induce adaptations in neuromuscular capacities that are specifically needed in actual balance-threatening situations (e.g. abilities to recover balance and to produce force explosively). Recent studies indicated that perturbation-based or multitask balance training and power/high-velocity resistance training have the potential to improve these specific capacities because they comply with the principle of training specificity. In fact, there is evidence that these specifically tailored training programmes are more effective in improving balance recovery mechanisms and muscle power than traditional training protocols. A few pilot studies have even shown that these recently designed training protocols have an impact on the reduction of fall incidence rate in older adults. Further research is needed to confirm these results and to elucidate the underlying mechanisms responsible for the adaptive processes.

Naturally fractured tight gas reservoir detection optimization

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-06-01

Building upon the partitioning of the Greater Green River Basin (GGRB) that was conducted last quarter, the goal of the work this quarter has been to conclude evaluation of the Stratos well and the prototypical Green River Deep partition, and perform the fill resource evaluation of the Upper Cretaceous tight gas play, with the goal of defining target areas of enhanced natural fracturing. The work plan for the quarter of November 1-December 31, 1998 comprised four tasks: (1) Evaluation of the Green River Deep partition and the Stratos well and examination of potential opportunity for expanding the use of E and P technology to low permeability, naturally fractured gas reservoirs, (2) Gas field studies, and (3) Resource analysis of the balance of the partitions.

The relevance of clinical balance assessment tools to differentiate balance deficits

OpenAIRE

Mancini, Martina; Horak, Fay B

2010-01-01

Control of balance is complex and involves maintaining postures, facilitating movement, and recovering equilibrium. Balance control consists of controlling the body center of mass over its limits of stability. Clinical balance assessment can help assess fall risk and/or determine the underlying reasons for balance disorders. Most functional balance assessment scales assess fall risk and the need for balance rehabilitation but do not differentiate types of balance deficits. A system approach t...

Radiatively-driven winds: model improvements, ionization balance and the infared spectrum

International Nuclear Information System (INIS)

Castor, J.I.

1979-01-01

Recent improvements to theoretical stellar wind models and the results of empirical modelling of the ionization balance and the infrared continuum are discussed. The model of a wind driven by radiation pressure in spectral lines is improved by accounting for overlap of the driving lines, dependence of ionization balance on density, and stellar rotation. These effects produce a softer velocity law than that given by Castor, Abbott and Klein (1975). The ionization balance in zeta Puppis is shown to agree with that estimated for an optically thick wind at a gas temperature of 60,000 K. The ionization model is not unique. The infrared continuum of zeta Pup measured by Barlow and Cohen is fitted to a cool model with a linear rise of velocity with radius; this fit is also not unique. It is concluded that one should try to find a model that fits several kinds of evidence simultaneously. (Auth.)

Midlatitude Forcing Mechanisms for Glacier Mass Balance Investigated Using General Circulation Models

NARCIS (Netherlands)

Reichert, B.K.; Bengtsson, L.; Oerlemans, J.

2001-01-01

A process-oriented modeling approach is applied in order to simulate glacier mass balance for individual glaciers using statistically downscaled general circulation models (GCMs). Glacier-specific seasonal sensitivity characteristics based on a mass balance model of intermediate complexity are used

Manure gas for use on the large-scale farm

Energy Technology Data Exchange (ETDEWEB)

Feraud, L

1954-10-01

A brief description is given of German installations for producing gas and fertilizer from farmyard manure by fermentation. The fertilizer is a semi-liquid sludge and has given better results with grass-land and potatoes than ordinary farmyard manure + balancing NPK has given.

Wind-Tunnel Balance Characterization for Hypersonic Research Applications

Science.gov (United States)

Lynn, Keith C.; Commo, Sean A.; Parker, Peter A.

2012-01-01

Wind-tunnel research was recently conducted at the NASA Langley Research Center s 31-Inch Mach 10 Hypersonic Facility in support of the Mars Science Laboratory s aerodynamic program. Researchers were interested in understanding the interaction between the freestream flow and the reaction control system onboard the entry vehicle. A five-component balance, designed for hypersonic testing with pressurized flow-through capability, was used. In addition to the aerodynamic forces, the balance was exposed to both thermal gradients and varying internal cavity pressures. Historically, the effect of these environmental conditions on the response of the balance have not been fully characterized due to the limitations in the calibration facilities. Through statistical design of experiments, thermal and pressure effects were strategically and efficiently integrated into the calibration of the balance. As a result of this new approach, researchers were able to use the balance continuously throughout the wide range of temperatures and pressures and obtain real-time results. Although this work focused on a specific application, the methodology shown can be applied more generally to any force measurement system calibration.

Balance Problems

Science.gov (United States)

... often, it could be a sign of a balance problem. Balance problems can make you feel unsteady. You may ... related injuries, such as a hip fracture. Some balance problems are due to problems in the inner ...

Carbon charges and natural gas use in China

International Nuclear Information System (INIS)

Skeer, Jeffrey; Wang Yanjia

2006-01-01

Substitution of natural gas for coal in China's power sector could significantly reduce emissions of carbon dioxide, but gas-fired power is generally more costly than coal-fired power in China today. This paper explores how carbon charges and carbon sequestration technology might tip the balance in favour of gas. The costs of electricity from new coal-fired and gas-fired power plants in China are compared under various assumptions about fuel costs, exchange rates, carbon dioxide charges, and application of carbon sequestration technology. Under average cost conditions today, gas-fired power is roughly two-thirds more costly than coal-fired power. But with a charge of $20/tonne of carbon dioxide, the costs of gas- and coal-fired power would typically be about equal. Over the longer term, carbon sequestration technology could be economical with a carbon dioxide charge of $22/tonne or more under typical cost conditions, but gas with sequestration would not have a clear cost advantage over coal with sequestration unless the charge exceeded $35/tonne

PID Controller Design for FES Applied to Ankle Muscles in Neuroprosthesis for Standing Balance.

Science.gov (United States)

Rouhani, Hossein; Same, Michael; Masani, Kei; Li, Ya Qi; Popovic, Milos R

2017-01-01

Closed-loop controlled functional electrical stimulation (FES) applied to the lower limb muscles can be used as a neuroprosthesis for standing balance in neurologically impaired individuals. The objective of this study was to propose a methodology for designing a proportional-integral-derivative (PID) controller for FES applied to the ankle muscles toward maintaining standing balance for several minutes and in the presence of perturbations. First, a model of the physiological control strategy for standing balance was developed. Second, the parameters of a PID controller that mimicked the physiological balance control strategy were determined to stabilize the human body when modeled as an inverted pendulum. Third, this PID controller was implemented using a custom-made Inverted Pendulum Standing Apparatus that eliminated the effect of visual and vestibular sensory information on voluntary balance control. Using this setup, the individual-specific FES controllers were tested in able-bodied individuals and compared with disrupted voluntary control conditions in four experimental paradigms: (i) quiet-standing; (ii) sudden change of targeted pendulum angle (step response); (iii) balance perturbations that simulate arm movements; and (iv) sudden change of targeted angle of a pendulum with individual-specific body-weight (step response). In paradigms (i) to (iii), a standard 39.5-kg pendulum was used, and 12 subjects were involved. In paradigm (iv) 9 subjects were involved. Across the different experimental paradigms and subjects, the FES-controlled and disrupted voluntarily-controlled pendulum angle showed root mean square errors of controlled balance were significantly smaller or tended to be smaller than those observed with voluntarily-controlled balance, implying improved steady-state and transient responses of FES-controlled balance. At the same time, the FES-controlled balance required similar torque levels (no significant difference) as voluntarily

Carbon balance variability in the Amazon Basin with climate change based on regular atmospheric profiling of greenhouse gases

Science.gov (United States)

Gatti, L.; Domingues, L. G.; Gloor, M.; Miller, J. B.; Peters, W.; Silva, M. G.; Correia, C. S. D. C.; Basso, L. S.; Alden, C. B.; Borges, V. F.; Marani, L.; Santos, R. S.; Crispim, S. P.; Sanches, A.; Costa, W. R.

2017-12-01

Net carbon exchange between tropical land and the atmosphere is potentially important because the vast amounts of carbon in forests and soils can be released on short time-scales e.g. via deforestation or changes in temperature and precipitation. Such changes may thus cause feedbacks on global climate as have been predicted in earth system models. The Amazon is the most significant region in the global carbon cycle, hosting by far the largest carbon vegetation and soil carbon pools ( 200 PgC). From 2010 onwards we have extended an earlier greenhouse gas measurement program to include regular vertical profiles of CO2 from the ground up to 4.5 km height at four sites along the main air-stream over the Amazon Basin. Our measurements demonstrate that surface flux signals are primarily concentrated to the lower 2 km and thus vertical profile measurements are ideally suited to estimate greenhouse gas balances. To understand the role of Amazon in global carbon budget it is important to maintain a long period of measurements that can represent the whole region. Our results already permit a range of insights about the magnitude, seasonality, inter-annual variation of carbon fluxes and their climate controls. Most recent years have been anomalously hot with the southern part of the Basin having warmed the most. Precipitation regimes also seem to have shifted with an increase in extreme floods. For the specific period we will discuss the period of 2010 to 2016, where the years 2010 and 2015/16 were anomalously dry and hot (both El Nino years) and the year 2013 was the wettest and coldest year. This period provides an interesting contrast of climatic conditions in a warming world with increasing human pressures and we will present the carbon balance for the basin during the last 7 years. We will analyze the effect of this climate variability on annual and seasonal carbon balances for these seven years using our atmospheric data. Our data permit us not only to estimate net CO2

Selling gas, selling services

International Nuclear Information System (INIS)

Moncel, V.

1999-01-01

Traditionally, the commercial activities of gas companies have been limited almost exclusively to the sale of gas. However, several socioeconomic factors specific to the gas industry, such as increasing customer expectations, competition between gas operators, a growing emphasis on services in many companies and the opening of public monopolies to competition, will bring inevitable change. Moreover, these developments coincide with imminent gas market opening. In response to the changing situation, the gas industry will seek to develop a range of multi-service offers, probably through external partnerships. (authors)

Specific model for a gas distribution analysis in the containment at Almaraz NPP using GOTHIC computer code

International Nuclear Information System (INIS)

García González, M.; García Jiménez, P.; Martínez Domínguez, F.

2016-01-01

To carry out an analysis of the distribution of gases within the containment building at the CN Almaraz site, a simulation model with the thermohydraulic GOTHIC [1] code has been used. This has been assessed with a gas control system based on passive autocatalytic recombiners (PARs). The model is used to test the effectiveness of the control systems for gases to be used in the Almaraz Nuclear Power Plant, Uits I&II (Caceres, Spain, 1,035 MW and 1,044 MW). The model must confirm the location and number of the recombiners proposed to be installed. It is an essential function of the gas control system to avoid any formation of explosive atmospheres by reducing and limiting the concentration of combustible gases during an accident, thus maintaining the integrity of the containment. The model considers severe accident scenarios with specific conditions that produce the most onerous generation of combustible gases.

Evolution of the economic importance of the oil and gas industrial sector in Brazil: impacts on macroeconomic indicators; Evolucao da importancia economica da industria de petroleo e gas natural no Brasil: contribuicao a variaveis macroeconomicas

Energy Technology Data Exchange (ETDEWEB)

Canelas, Andre Luis de Souza

2007-06-15

This thesis analyzes the evolution of the macroeconomic importance of the oil and gas sector in Brazil, in the recent years, which is represented by its contribution to the macroeconomic indicators, which are: GDP, Investment, Foreign Direct Investment, Trade Balance, Tax Revenue, Jobs, Wages and Inflation. The results found indicate that the oil and gas sector has a relevant contribution to the values of the Brazilian GDP, total amount of investment, total amount of foreign direct investment, tax revenue, inflation and trade balance, whereas this sector has a less relevant impact for the creation of jobs and wages in Brazil. (author)

Simulation of the water balance of boreal watersheds of northeastern British Columbia, Canada using MIKE SHE, an integrated hydrological model

Science.gov (United States)

Abadzadesahraei, S.; Déry, S.; Rex, J. F.

2016-12-01

Northeastern British Columbia (BC) is undergoing rapid development for oil and gas extraction, largely depending on subsurface hydraulic fracturing (fracking), which relies on available freshwater. Even though this industrial activity has made substantial contributions to regional and provincial economies, it is important to ensure that sufficient and sustainable water supplies are available for all those dependent on the resource, including ecological systems. Further, BC statistics predict that the northeastern region's population will increase by 30% over the next 25 years, thereby amplifying the demands of domestic and industrial water usage. Hence, given the increasing demands for surface water in the complex wetlands of northeastern BC, obtaining accurate long-term water balance information is of vital importance. Thus, this study aims to simulate the 1979-2014 water balance at two boreal watersheds using the MIKE SHE model. More specifically, this research intends to quantify the historical, and regional, water budgets and their associated hydrological processes at two boreal watersheds—the Coles Lake and Tsea Lake watersheds—in northeastern BC. The development of coupled groundwater and surface water model of these watersheds are discussed. The model setup, calibration process, and results are presented, focusing on the water balance of boreal watersheds. Hydrological components within these watersheds are quantified through a combination of intensive fieldwork, observational data, analysis and numerical modeling. The output from the model provides important information for decision makers to manage water resources in northeastern BC. Keywords: Northeastern BC; boreal watershed; water balance; MIKE SHE hydrological model.

Hydrogen permeation measurement of the reduced activation ferritic steel F82H by the vacuum thermo-balance method

International Nuclear Information System (INIS)

Yoshida, Hajime; Enoeda, Mikio; Abe, Tetsuya; Akiba, Masato

2005-03-01

Hydrogen permeation fluxes of the reduced activation ferritic steel F82H were quantitatively measured by a newly proposed method, vacuum thermo-balance method, for a precise estimation of tritium leakage in a fusion reactor. We prepared sample capsules made of F82H, which enclosed hydrogen gas. The hydrogen in the capsules permeated through the capsule wall, and subsequently desorbed from the capsule surface during isothermal heating. The vacuum thermo-balance method allows simultaneous measurement of the hydrogen permeation flux by two independent methods, namely, the net weight reduction of the sample capsule and exhaust gas analysis. Thus the simultaneous measurements by two independent methods increase the reliability of the permeability measurement. When the gas pressure of enclosed hydrogen was 0.8 atm at the sample temperature of 673 K, the hydrogen permeation flux of F82H obtained by the net weight reduction and the exhaust gas analysis was 0.75x10 18 (H 2 /m 2 s) and 2.2x10 18 (H 2 /m 2 s), respectively. The ratio of the hydrogen permeation fluxes obtained by the net weight reduction to that measured by the exhaust gas analysis was in the range from 1/4 to 1/1 in this experiment. The temperature dependence of the estimated permeation flux was similar in both methods. Taking the uncertainties of both measurements into consideration, both results are supposed to be consistent. The enhancement of hydrogen permeation flux was observed from the sample of which outer surface was mechanically polished. Through the present experiments, it has been demonstrated that the vacuum thermo-balance method is effective for the measurement of hydrogen permeation rate of F82H. (author)

Negative leave balances

CERN Multimedia

Human Resources Department

2005-01-01

Members of the personnel entitled to annual leave and, where appropriate, saved leave and/or compensatory leave are requested to take note of the new arrangements described below, which were recommended by the Standing Concertation Committee (SCC) at its meeting on 1Â September 2005 and subsequently approved by the Director-General. The changes do not apply to members of the personnel participating in the Progressive Retirement Programme (PRP) or the Part-time Work as a pre-retirement measure, for whom the specific provisions communicated at the time of joining will continue to apply. Â Negative balances in annual leave, saved leave and/or compensatory leave accounts at the end of the leave year (30th September) and on the date on which bonuses are credited to the saved leave account (31st December): Where members of the personnel have a leave account with a negative balance on 30Â September and/or 31Â December, leave will automatically be transferred from one account to another on the relevant dates i...

Negative leave balances

CERN Multimedia

Human Resources Department

2005-01-01

Members of the personnel entitled to annual leave and, where appropriate, saved leave and/or compensatory leave are requested to take note of the new arrangements described below, which were recommended by the Standing Concertation Committee (SCC) at its meeting on 1 September 2005 and subsequently approved by the Director-General. The changes do not apply to members of the personnel participating in the Progressive Retirement Programme (PRP) or the Part-time Work as a pre-retirement measure, for whom the specific provisions communicated at the time of joining will continue to apply.  Negative balances in annual leave, saved leave and/or compensatory leave accounts at the end of the leave year (30th September) and on the date on which bonuses are credited to the saved leave account (31st December): Where members of the personnel have a leave account with a negative balance on 30 September and/or 31 December, leave will automatically be transferred from one account to another on the relevant dates in or...

Interchangeability of the Wii Balance Board for Bipedal Balance Assessment

OpenAIRE

Bonnech?re, Bruno; Jansen, Bart; Omelina, Lubos; Rooze, Marcel; Van Sint Jan, Serge

2015-01-01

Background Since 2010, an increasing interest in more portable and flexible hardware for balance and posture assessment led to previously published studies determining whether or not the Wii Balance Board could be used to assess balance and posture, both scientifically and clinically. However, no previous studies aimed at comparing results from different Wii Balance Boards for clinical balance evaluation exist. Objective The objective of this crossover study is to assess the interchangeabilit...

Air-water Gas Exchange Rates on a Large Impounded River Measured Using Floating Domes (Poster)

Science.gov (United States)

Mass balance models of dissolved gases in rivers typically serve as the basis for whole-system estimates of greenhouse gas emission rates. An important component of these models is the exchange of dissolved gases between air and water. Controls on gas exchange rates (K) have be...

[Specific detection of urinary sympathomimetic amines for control of anti-doping by gas chromatography-mass spectroscopy].

Science.gov (United States)

Franceschini, A; Duthel, J M; Vallon, J J

1991-03-22

A specific, sensitive and reliable gas chromatography-mass spectrometry (GC-MS) technique for detection of sympathomimetic amines following urinary extraction is proposed. Amphetamine, phentermine, ephedrine, mephenorex, methylphenidate, benzphetamine, clobenzorex and internal standard (fenfluramine) are extracted from urines at pH 7.0 using elution by chloroform-isopropanol on C18 cartridges. Derivatization followed by GC-MS analysis allows identification of these drugs founded on relative retention times and mass spectra. The quantitation limit for derivatizable drugs was found to be 200 ng/ml and 500 ng/ml for underivatizable drugs.

Stochastic solution of population balance equations for reactor networks

International Nuclear Information System (INIS)

Menz, William J.; Akroyd, Jethro; Kraft, Markus

2014-01-01

This work presents a sequential modular approach to solve a generic network of reactors with a population balance model using a stochastic numerical method. Full-coupling to the gas-phase is achieved through operator-splitting. The convergence of the stochastic particle algorithm in test networks is evaluated as a function of network size, recycle fraction and numerical parameters. These test cases are used to identify methods through which systematic and statistical error may be reduced, including by use of stochastic weighted algorithms. The optimal algorithm was subsequently used to solve a one-dimensional example of silicon nanoparticle synthesis using a multivariate particle model. This example demonstrated the power of stochastic methods in resolving particle structure by investigating the transient and spatial evolution of primary polydispersity, degree of sintering and TEM-style images. Highlights: •An algorithm is presented to solve reactor networks with a population balance model. •A stochastic method is used to solve the population balance equations. •The convergence and efficiency of the reported algorithms are evaluated. •The algorithm is applied to simulate silicon nanoparticle synthesis in a 1D reactor. •Particle structure is reported as a function of reactor length and time

An Analysis of Policy Issues in Natural Gas Industry Restructuring

Energy Technology Data Exchange (ETDEWEB)

Seo, J.K. [Korea Energy Economics Institute, Euiwang (Korea)

2001-12-01

This report explores controversial issues and problems that could emerge in the process of implementing the government's restructuring plan for natural gas industry and aims to suggest policy directions regarding the restructuring. To begin with, it examines current conditions surrounding natural gas industry including domestic demand and supply conditions, world LNG market trend, structural changes of the industry in OECD countries, possibilities of introducing effective competition and assignment of existing import contracts. In doing so, we probe whether the direction of the natural gas industry restructuring is proper and suggest that the results be reflected when a more detailed restructuring implementation plan is formulated. Also, this report suggests possible schemes related to major institutional changes expected by the basic restructuring plan and the detailed restructuring implementation plan announced by the government. First, it presents several alternative ways to properly divide up the import/wholesales section of Korea Gas Corporation. Second, it examines critical issues such as the method of using gas supply facilities and gas balancing mechanism, and presents adoptable alternatives for each issue. These issues constitute the core of network and market operation rules which need to be in place when adopting an open access system, which in turn is a prerequisite for sales competition. Third, the report examines price systems, including gas commodity pricing and rate-making design for transportation service, by first anticipating the direction of changes in gas rate regulation. Specifically, it presents possible ways to design the service rate for each function of pipeline network and import terminals, and discusses controversial issues in determining total cost-of-service and allocating the cost-of-service to each functional service offered such as distance-related rates, interruptible service rate. Lastly, in relation to the opening of retail

The importance of LNG for natural gas consumption in the EU

Directory of Open Access Journals (Sweden)

Metelska Klaudia

2016-01-01

Full Text Available The World market of liquefied natural gas (LNG is growing rapidly. In 2015 LNG production exceeded 333 bcm with its predicted increase up to 450 bcm in 2019. The analysis of LNG role in natural gas import to the EU in recent years shows variability: LNG share in overall import reached 25% in 2011 and it went down to 15% in 2014. The smaller demand for natural gas including LNG in the EU can be due to, among others, a slower economic growth and a dynamic development of the use of renewable energy sources. The article shows the role of natural gas in the structure of consumption of primary energy as well as the changes in demand for natural gas in the years 2007–2014 for the main groups of end users: industry, energy production and individual households. The biggest fall in demand for natural gas has been observed in energy production sector in recent years. This publication continues to analyse the structure of natural gas supplies to the EU, with special emphasis on the directions of LNG import to the countries such as: The UK, Spain, France, Greece, Belgium, Portugal, Italy, Lithuania and The Netherlands. The significance of LNG in the balance of consumption of natural gas in these countries has been presented as well as the infrastructure connected with LNG and plans of development of regasification terminals. In the summary the most important conclusions have been drawn and a chance of the increase in significance of the role of LNG in the balance of natural gas supplies has been pointed out, which is due to the steep fall of LNG prices which has taken place in recent years.

Manual gas tungsten arc (dc) and semiautomatic gas metal arc welding of 6XXX aluminum. Welding procedure specification

International Nuclear Information System (INIS)

Wodtke, C.H.; Frizzell, D.R.; Plunkett, W.A.

1985-08-01

Procedure WPS-1009 is qualified under Section IX of the ASME Boiler and Pressure Vessel Code for manual gas tungsten arc (DC) and semiautomatic gas metal arc (DC) welding of aluminum alloys 6061 and 6063 (P-23), in thickness range 0.187 to 2 in.; filler metal is ER4043 (F-23); shielding gases are helium (GTAW) and argon (GMAW)

Energy statistics and balances of non-OECD countries 1993-1994

International Nuclear Information System (INIS)

1996-01-01

Contains a compilation of energy supply and consumption statistics for more than 100 non-OECD countries and regions, including developing countries Central and Eastern European countries and the former USSR. Data are expressed in original units and in common units for coal, oil, gas, electricity, heat and combustible renewable and waste. Historical tables for both individual countries and regions summarize data on coal, oil, gas and electricity production, trade and consumption as well as main energy and economic indicators since 1971. Each issue includes definitions of products and flows and notes on the individual countries as well as conversion factors from original units to common energy units. Similar data for OECD are available in the IEA Energy Statistics and Energy Balances of OECD Countries. (author)

NOVEL GAS CLEANING/CONDITIONING FOR INTEGRATED GASIFICATION COMBINED CYCLE

Energy Technology Data Exchange (ETDEWEB)

Dennis A. Horazak; Richard A. Newby; Eugene E. Smeltzer; Rachid B. Slimane; P. Vann Bush; James L. Aderhold Jr; Bruce G. Bryan

2005-12-01

individual gas cleaning stages, and the probable operating conditions of the gas cleaning stages to conceptually satisfy the gas cleaning requirements; (2) Estimate process material & energy balances for the major plant sections and for each gas cleaning stage; (3) Conceptually size and specify the major gas cleaning process equipment; (4) Determine the resulting overall performance of the application; and (5) Estimate the investment cost and operating cost for each application. Analogous evaluation steps were applied for each application using conventional gas cleaning technology, and comparison was made to extract the potential benefits, issues, and development needs of the Filter-Reactor Novel Gas Cleaning technology. The gas cleaning process and related gas conditioning steps were also required to meet specifications that address plant environmental emissions, the protection of the gas turbine and other Power Island components, and the protection of the methanol synthesis reactor. Detailed material & energy balances for the gas cleaning applications, coupled with preliminary thermodynamic modeling and laboratory testing of candidate sorbents, identified the probable sorbent types that should be used, their needed operating conditions in each stage, and their required levels of performance. The study showed that Filter-Reactor Novel Gas Cleaning technology can be configured to address and conceptually meet all of the gas cleaning requirements for IGCC, and that it can potentially overcome several of the conventional IGCC power plant availability issues, resulting in improved power plant thermal efficiency and cost. For IGCC application, Filter-Reactor Novel Gas Cleaning yields 6% greater generating capacity and 2.3 percentage-points greater efficiency under the Current Standards case, and more than 9% generating capacity increase and 3.6 percentage-points higher efficiency in the Future Standards case. While the conceptual equipment costs are estimated to be only slightly

Greenhouse gas balance of mountain dairy farms as affected by grassland carbon sequestration.

Science.gov (United States)

Salvador, Sara; Corazzin, Mirco; Romanzin, Alberto; Bovolenta, Stefano

2017-07-01

Recent studies on milk production have often focused on environmental impacts analysed using the Life Cycle Assessment (LCA) approach. In grassland-based livestock systems, soil carbon sequestration might be a potential sink to mitigate greenhouse gas (GHG) balance. Nevertheless, there is no commonly shared methodology. In this work, the GHG emissions of small-scale mountain dairy farms were assessed using the LCA approach. Two functional units, kg of Fat and Protein Corrected Milk (FPCM) and Utilizable Agricultural Land (UAL), and two different emissions allocations methods, no allocation and physical allocation, which accounts for the co-product beef, were considered. Two groups of small-scale dairy farms were identified based on the Livestock Units (LU) reared: 30 LU (HLU). Before considering soil carbon sequestration in LCA, performing no allocation methods, LLU farms tended to have higher GHG emission than HLU farms per kg of FPCM (1.94 vs. 1.59 kg CO 2 -eq/kg FPCM, P ≤ 0.10), whereas the situation was reversed upon considering the m 2 of UAL as a functional unit (0.29 vs. 0.89 kg CO 2 -eq/m 2 , P ≤ 0.05). Conversely, considering physical allocation, the difference between the two groups became less noticeable. When the contribution from soil carbon sequestration was included in the LCA and no allocation method was performed, LLU farms registered higher values of GHG emission per kg of FPCM than HLU farms (1.38 vs. 1.10 kg CO 2 -eq/kg FPCM, P ≤ 0.05), and the situation was likewise reversed in this case upon considering the m 2 of UAL as a functional unit (0.22 vs. 0.73 kg CO 2 -eq/m 2 , P ≤ 0.05). To highlight how the presence of grasslands is crucial for the carbon footprint of small-scale farms, this study also applied a simulation for increasing the forage self-sufficiency of farms to 100%. In this case, an average reduction of GHG emission per kg of FPCM of farms was estimated both with no allocation and with physical allocation

Compression of turbulent magnetized gas in giant molecular clouds

Science.gov (United States)

Birnboim, Yuval; Federrath, Christoph; Krumholz, Mark

2018-01-01

Interstellar gas clouds are often both highly magnetized and supersonically turbulent, with velocity dispersions set by a competition between driving and dissipation. This balance has been studied extensively in the context of gases with constant mean density. However, many astrophysical systems are contracting under the influence of external pressure or gravity, and the balance between driving and dissipation in a contracting, magnetized medium has yet to be studied. In this paper, we present three-dimensional magnetohydrodynamic simulations of compression in a turbulent, magnetized medium that resembles the physical conditions inside molecular clouds. We find that in some circumstances the combination of compression and magnetic fields leads to a rate of turbulent dissipation far less than that observed in non-magnetized gas, or in non-compressing magnetized gas. As a result, a compressing, magnetized gas reaches an equilibrium velocity dispersion much greater than would be expected for either the hydrodynamic or the non-compressing case. We use the simulation results to construct an analytic model that gives an effective equation of state for a coarse-grained parcel of the gas, in the form of an ideal equation of state with a polytropic index that depends on the dissipation and energy transfer rates between the magnetic and turbulent components. We argue that the reduced dissipation rate and larger equilibrium velocity dispersion has important implications for the driving and maintenance of turbulence in molecular clouds and for the rates of chemical and radiative processes that are sensitive to shocks and dissipation.

Fiscal 2000 report on result. Phase-1 R and D on closed type high efficiency gas turbine technology corresponding to recovery of carbon dioxide; 2000 nendo nisanka tanso kaishu taio closed gata kokoritsu gas turbine gijutsu dai 1 ki kenkyu kaihatsu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Technological development is aimed at a 500MW class gas turbine plant with a generator-end efficiency of over 60%, while using a 1,700 degree C class ultra high temperature gas turbine by natural gas fuel and fully collecting CO{sub 2} in the exhaust gas through an oxygen combustion closed type system. The paper describes the results of fiscal 2000. A conceptual design was made on the basis of a tentatively set second mass and heat balance concerning the closed cycle that facilitated CO{sub 2} recovery by methane-oxygen combustion, with a system optimization method examined by parameter studies (sensitivity analysis of the effect of each parameter on the generator-end efficiency). Using the zero-th conceptual design implemented in fiscal 1999, the first mass and heat balance (generator-end efficiency 58%) and the results of parameter studies, the system optimization was continuously examined, deciding the second mass and heat balance. A calculation of 59.8% was obtained for the generator-end efficiency. A study was conducted on a closed system verification machine based on the ME-1000 gas turbine by Mitsubishi Heavy Industries, Ltd. The premises of CRIEPI (Central Research Institute of Electric Power Industry) Yokosuka laboratory was assumed to be the installation site for the machine. (NEDO)

A coupling model for gas diffusion and seepage in SRV section of shale gas reservoirs

Directory of Open Access Journals (Sweden)

Shusheng Gao

2017-03-01

Full Text Available A prerequisite to effective shale gas development is a complicated fracture network generated by extensive and massive fracturing, which is called SRV (stimulated reservoir volume section. Accurate description of gas flow behaviors in such section is fundamental for productivity evaluation and production performance prediction of shale gas wells. The SRV section is composed of bedrocks with varying sizes and fracture networks, which exhibit different flow behaviors – gas diffusion in bedrocks and gas seepage in fractures. According to the porosity and permeability and the adsorption, diffusion and seepage features of bedrocks and fractures in a shale gas reservoir, the material balance equations were built for bedrocks and fractures respectively and the continuity equations of gas diffusion and seepage in the SRV section were derived. For easy calculation, the post-frac bedrock cube was simplified to be a sphere in line with the principle of volume consistency. Under the assumption of quasi-steady flow behavior at the cross section of the sphere, the gas channeling equation was derived based on the Fick's laws of diffusion and the density function of gas in bedrocks and fractures. The continuity equation was coupled with the channeling equation to effectively characterize the complicated gas flow behavior in the SRV section. The study results show that the gas diffusivity in bedrocks and the volume of bedrocks formed by volume fracturing (or the scale of fracturing jointly determines the productivity and stable production period of a shale gas well. As per the actual calculation for the well field A in the Changning–Weiyuan Block in the Sichuan Basin, the matrix has low gas diffusivity – about 10−5 cm2/s and a large volume with an equivalent sphere radius of 6.2 m, hindering the gas channeling from bedrocks to fractures and thereby reducing the productivity of the shale gas well. It is concluded that larger scale of volume fracturing

2008 annual site restoration report of the BC Oil and Gas Commission

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-15

Oil and gas operators in British Columbia are responsible for all issues related to the surface reclamation of a site, including the management of contaminated sites. They require a certificate of restoration (CoR) for lands no longer required in the extraction of hydrocarbons. The CoR program ensures that the land used for oil and development is restored to a safe and productive state. The restoration process promotes the timely recovery of wellsite and facility locations and helps in managing environmental impacts. The BC Oil and Gas Commission oversees the restoration process by oil and gas operators through the application of regulations, compliance and enforcement. The Commission balances a broad range of environmental, economic and social considerations. Among its specific objectives are public safety, conservation of petroleum resources, promoting a healthy environment, and equitable participation in production. This report included a review of performance measures that have been developed to evaluate restoration programs, including well plugging. Site reclamation requirements for lands within the Agricultural Land Reserve (ALR) were also described along with orphan site reclamation activities. A CoR is issued after a permit holder demonstrates that the remediation criteria have been met. There are currently 3,814 sites that have received a CoR in the province. refs., tabs., figs.

Rising prices squeeze gas marketer

Energy Technology Data Exchange (ETDEWEB)

Lunan, D.

2000-06-19

Apollo Gas, a Toronto-based gas marketer, is considering options to enhance unit holder value, including sale of its 21,000 gas supply contracts, just weeks after it was forced out of the Alberta market by rising gas prices. Although the company had reported first quarter revenues of more than $15 million and earnings through that period of about $2.1 million, increases of 33 per cent and 38 per cent respectively over the same period in 1999, the company is resigned to the fact that such performance markers are not likely to be reached again in the foreseeable future, hence the decision to sell. About 95 per cent of Apollo's current transportation service volumes are matched to existing fixed-price supply contract which are due to expire in November 2000. After that, it is about 75 per cent matched for the balance of the term of its customer contracts (mostly five years). This means that the company is exposed to market prices that are likely to continue to increase. If this prediction holds true, Apollo would be forced to purchase the unhedged volumes of gas it needs to service its customers in the spot market at prices higher than prices the company is charging to its customers.

Rising prices squeeze gas marketer

International Nuclear Information System (INIS)

Lunan, D.

2000-01-01

Apollo Gas, a Toronto-based gas marketer, is considering options to enhance unit holder value, including sale of its 21,000 gas supply contracts, just weeks after it was forced out of the Alberta market by rising gas prices. Although the company had reported first quarter revenues of more than $15 million and earnings through that period of about $2.1 million, increases of 33 per cent and 38 per cent respectively over the same period in 1999, the company is resigned to the fact that such performance markers are not likely to be reached again in the foreseeable future, hence the decision to sell. About 95 per cent of Apollo's current transportation service volumes are matched to existing fixed-price supply contract which are due to expire in November 2000. After that, it is about 75 per cent matched for the balance of the term of its customer contracts (mostly five years). This means that the company is exposed to market prices that are likely to continue to increase. If this prediction holds true, Apollo would be forced to purchase the unhedged volumes of gas it needs to service its customers in the spot market at prices higher than prices the company is charging to its customers

A simple technique for continuous measurement of time-variable gas transfer in surface waters

Science.gov (United States)

Tobias, Craig R.; Bohlke, John Karl; Harvey, Judson W.; Busenberg, Eurybiades

2009-01-01

Mass balance models of dissolved gases in streams, lakes, and rivers serve as the basis for estimating wholeecosystem rates for various biogeochemical processes. Rates of gas exchange between water and the atmosphere are important and error-prone components of these models. Here we present a simple and efficient modification of the SF6 gas tracer approach that can be used concurrently while collecting other dissolved gas samples for dissolved gas mass balance studies in streams. It consists of continuously metering SF6-saturated water directly into the stream at a low rate of flow. This approach has advantages over pulse injection of aqueous solutions or bubbling large amounts of SF6 into the stream. By adding the SF6 as a saturated solution, we minimize the possibility that other dissolved gas measurements are affected by sparging and/or bubble injecta. Because the SF6 is added continuously we have a record of changing gas transfer velocity (GTV) that is contemporaneous with the sampling of other nonconservative ambient dissolved gases. Over a single diel period, a 30% variation in GTV was observed in a second-order stream (Sugar Creek, Indiana, USA). The changing GTV could be attributed in part to changes in temperature and windspeed that occurred on hourly to diel timescales.

The Integration of Gasification Systems with Gas Engine to Produce Electrical Energy from Biomass

Science.gov (United States)

Siregar, K.; Alamsyah, R.; Ichwana; Sholihati; Tou, S. B.; Siregar, N. C.

2018-05-01

The need for energy especially biomass-based renewable energy continues to increase in Indonesia. The objective of this research was to design downdraft gasifier machine with high content of combustible gas on gas engine. Downdraft gasifier machine was adjusted with the synthetic gas produced from biomass. Besides that, the net energy ratio, net energy balance, renewable index, economic analysis, and impact assessment also been conducted. Gas engine that was designed in this research had been installed with capacity of 25 kW with diameter and height of reactor were 900 mm and 1000 mm respectively. The method used here were the design the Detailed Engineering Design (DED), assembly, and performance test of gas engine. The result showed that gas engine for biomass can be operated for 8 hours with performance engine of 84% and capacity of 25 kW. Net energy balance, net energy ratio, and renewable index was 30 MJ/kWh-electric; 0.89; 0.76 respectively. The value of GHG emission of Biomass Power Generation is 0.03 kg-CO2eq/MJ. Electrical production cost for Biomass Power Generation is about Rp.1.500,/kWh which is cheaper than Solar Power Generation which is about of Rp. 3.300,-/kWh.

Comparison of the Mini-Balance Evaluations Systems Test with the Berg Balance Scale in relationship to walking speed and motor recovery post stroke.

Science.gov (United States)

Madhavan, Sangeetha; Bishnoi, Alka

2017-12-01

The Mini-BESTest is a recently developed balance assessment tool that incorporates challenging dynamic balance tasks. Few studies have compared the psychometric properties of the Mini-BESTest to the commonly used Berg Balance Scale (BBS). However, the utility of these scales in relationship to post stroke walking speeds has not been explored. The purpose of this study was to compare the sensitivity and specificity of the Mini-BESTest and BBS to evaluate walking speeds in individuals with stroke. A retrospective exploratory design. Forty-one individuals with chronic stroke were evaluated with the Mini-BESTest, BBS, and 10-meter self-selected walk test (10MWT). Based on their self-selected gait speeds (below or above 0.8 m/s), participants were classified as slow and fast walkers. Significant linear correlations were observed between the Mini-BESTest vs. BBS (r = 0.72, p ≤ 0.001), Mini-BESTest vs. 10MWT (r = 0.58, p ≤ 0.001), and BBS vs. 10MWT (r = 0.30, p = 0.05). Independent t-tests comparing the balance scores for the slow and fast walkers revealed significant group differences for the Mini-BESTest (p = 0.003), but not for the BBS (p = 0.09). The Mini-BESTest demonstrated higher sensitivity (93%) and specificity (64%) compared to the BBS (sensitivity 81%, specificity 56%) for discriminating participants into slow and fast walkers. The Mini-BESTest has a greater discriminative ability than the BBS to categorize individuals with stroke into slow and fast walkers.

Theoretical study of the building principal of internal and external energy balances structures in diesel engine

Directory of Open Access Journals (Sweden)

Djallel ZEBBAR

2016-06-01

Full Text Available Distribution knowledge of the energy introduced into the combustion chamber is of great importance in the theory of internal combustion engines. This work aims to highlight the very complex relationship, often indistinguishable between internal and external energy balances components. The scrutiny of internal balance components has permitted to trace back up to the external balance. This can be easily established on a test bench equipped for the occasion. It will assess the perfection of energy's use, the heat loss and the possibility of their reducing, the energy efficiency of exhaust gas use, the possibility and ways of engine operating parameters improving and finally it will allowing to calculate the cooling and energy recovery systems.