Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data

Energy Technology Data Exchange (ETDEWEB)

Drlica-Wagner, A.; et al.

2015-08-04

Due to their proximity, high dark-matter (DM) content, and apparent absence of non-thermal processes, Milky Way dwarf spheroidal satellite galaxies (dSphs) are excellent targets for the indirect detection of DM. Recently, eight new dSph candidates were discovered using the first year of data from the Dark Energy Survey (DES). We searched for gamma-ray emission coincident with the positions of these new objects in six years of Fermi Large Area Telescope data. We found no significant excesses of gamma-ray emission. Under the assumption that the DES candidates are dSphs with DM halo properties similar to the known dSphs, we computed individual and combined limits on the velocity-averaged DM annihilation cross section for these new targets. If the estimated DM content of these dSph candidates is confirmed, they will constrain the annihilation cross section to lie below the thermal relic cross section for DM particles with masses $\\lesssim 20\\,\\mathrm{GeV}$ annihilating via the $b\\bar{b}$ or τ(+)τ(-) channels.

La demande de bois-énergie à Ouagadougou : esquisse d’évaluation de l’impact physique et des échecs des politiques de prix

Directory of Open Access Journals (Sweden)

Boukary Ouedraogo

2006-03-01

Full Text Available Cet article vise à évaluer non seulement la demande de bois-énergie de la ville de Ouagadougou, l’impact de cette demande sur le patrimoine forestier de l’aire d’approvisionnement de cette ville, mais aussi l’esquisse d’une évaluation des échecs des politiques de prix du bois-énergie. Les méthodes d’évaluation de la consommation de cette source d’énergie sont passées en revue au regard des conditions d’offre de la ressource et des données existantes sur la demande de cette ressource. Les données sur les inventaires forestiers de l’aire d’approvisionnement de Ouagadougou en bois-énergie, ainsi que des enquêtes sur les ménages et les artisans ont permis d’estimer la consommation de Ouagadougou en bois-énergie et son impact sur l’épuisement des ressources forestières du pays.This paper aims at evaluating not only the wood-energy demand of Ouagadougou, the physic impact of this city wood energy consumption on the forest of its provisioning area, together with the causes of wood-energy price policy failures. The evaluation’s methods of wood energy consumption are reviewed in comparison with the resource supply conditions and the availability on data of wood resource demand. The data on the forest inventories of the wood-energy provisioning surface of Ouagadougou, as well as investigations into the households and the craftsmen allows estimating the consumption of Ouagadougou in wood-energy and its impact on the forest resources’ depletion. some complementary analysis have been done on the main causes of wood energy price policy failures.

Risques et impacts environnementaux des retenues d’altitude pour la production de neige de culture dans un contexte de changement climatique

Directory of Open Access Journals (Sweden)

Stéphanie Gaucherand

2011-10-01

Full Text Available Les retenues d’altitude sont des ouvrages hydrauliques implantés dans les stations de loisirs de montagne et destinés à créer une réserve d’eau, dédiée principalement à la production de neige de culture. Leur implantation en altitude en fait indubitablement des retenues spécifiques, subissant et induisant des risques et des impacts sur leur environnement anthropique et écologique. Le Cemagref a engagé un projet de recherche sur la sûreté des retenues d’altitude. Le présent article est issu de ces travaux et vise à établir un état des lieux des risques liés aux retenues d’altitude et de leurs impacts sur l’environnement. Il replace le développement des retenues d’altitude dans leurs contextes sociétal, social et environnemental. Il développe ensuite les risques et impacts des retenues d’altitude, en focalisant son analyse sur les différents risques et aléas spécifiques auxquels sont exposés les ouvrages, et sur les différents impacts environnementaux liés à la réalisation et la gestion des retenues.Mountain reservoirs are hydraulic structures implanted in recreational mountain resorts designed to provide a water reserve mainly used for the production of artificial snow. Their implantation in high-altitude zones makes them highly specific reservoirs subjected to and inducing risks and impacts on their human and ecological environment. Based on in-depth bibliographic and field research, Cemagref has launched a study on mountain reservoirs. The present article aims to establish the current state of the risks related to mountain reservoirs and their impacts on the environment, placing the development of mountain reservoirs in their societal, social, and environmental contexts. It will then develop mountain reservoir risks and impacts, focusing on the specific risks and uncertainties to which these structures are exposed, and the different environmental impacts related to the construction and management of

Photon emission from massive projectile impacts on solids.

Science.gov (United States)

Fernandez-Lima, F A; Pinnick, V T; Della-Negra, S; Schweikert, E A

2011-01-01

First evidence of photon emission from individual impacts of massive gold projectiles on solids for a number of projectile-target combinations is reported. Photon emission from individual impacts of massive Au(n) (+q) (1 ≤ n ≤ 400; q = 1-4) projectiles with impact energies in the range of 28-136 keV occurs in less than 10 ns after the projectile impact. Experimental observations show an increase in the photon yield from individual impacts with the projectile size and velocity. Concurrently with the photon emission, electron emission from the impact area has been observed below the kinetic emission threshold and under unlikely conditions for potential electron emission. We interpret the puzzling electron emission and correlated luminescence observation as evidence of the electronic excitation resulting from the high-energy density deposited by massive cluster projectiles during the impact.

Bâle 3 : Quels impacts sur le financement des pays émergents ?

OpenAIRE

Figuet, Jean-Marc; Humblot, Thomas; Lahet, Delphine

2013-01-01

La persistance de crises bancaires démontre l'incapacité des établissements de crédit à s'autoréguler. De ce fait, le Comité de Bâle étend largement le périmètre de la nouvelle règlementation prudentielle. Sur la base de la littérature sur les déterminants des flux de capitaux transfrontières et d'un GMM système, cet article analyse l'impact potentiel de l'accord Bâle 3 sur les flux de capitaux bancaires provenant des banques de 16 pays industrialisés à destination d'un panel de 30 pays émerg...

Des dispositions responsables à prendre pour la protection des ...

African Journals Online (AJOL)

En considérant l'effet néfaste des maladies, des parasites, du changement climatique et d'autres facteurs environnementaux (les OGM par exemple) sur la survie des abeilles, la baisse de leurs populations dans certaines parties du monde ne saurait être attribuée aux seules pesticides. En plus, l'impact de ces derniers sur ...

Impact des TIC sur la motivation et la réussite des étudiants Enquête à l’Université d’Abomey-Calavi au Bénin

Directory of Open Access Journals (Sweden)

Serge Armel Attenoukon

2013-01-01

Full Text Available Cette étude tente d’explorer, dans un contexte de forts taux d’échec des apprenants des facultés classiques à l’Université d’Abomey-Calavi (Bénin, les perceptions des étudiants et des enseignants quant à l’impact des TIC tant sur la motivation que sur la réussite des apprenants. L’étude est tout particulièrement importante dans notre contexte où les TIC sont de plus en plus utilisées en pédagogie universitaire et où les étudiants y recourent dans leur pratique plus que les formateurs dans la leur. Au total, 171 questionnaires ont été remplis par les étudiants et les enseignants; 11 apprenants et 6 enseignants ont passé des entrevues semi-dirigées. Des analyses statistiques et qualitatives de ces données révèlent que les étudiants et les enseignants soulignent, dans leur majorité, le potentiel motivationnel des TIC, notamment de l’ordinateur et d’Internet, pour l’apprentissage. Elles ont cependant montré une position plus mitigée entre les étudiants et les enseignants en ce qui concerne l’effet positif des TIC pour la réussite des études.

Influence de l'occupation des terres sur la dynamique des ...

African Journals Online (AJOL)

L'objectif de la présente étude est d'évaluer l'impact de mise en culture, des pâturages, des jachères et l'influence des villages sur la dynamique des communautés végétales de la commune de ..... mais il n'y a que peu de recrutement. Au-delà de cinq ans, taille et phytovolume diminuent, témoignant du vieillissement de la ...

Étude des impacts écologiques du dynamisme spatio-temporel des ...

African Journals Online (AJOL)

transformer radicalement les occupations du sol. Toutefois, le recul des .... également de cette protection (Roberge et Angelstam 2004). L'objectif est de ... distribution des espèces cibles a ensuite été cartographiée sur la couche d'unités de ...

L’IMPACT DE L’APPLICATION DES REFORMES BALE III SUR L’INDUSTRIE BANCAIRE ROUMAINE

Directory of Open Access Journals (Sweden)

Maria Halep

2012-12-01

Full Text Available Le début du XXIème a connu un essor remarquable des marchés financiers, de l’innovation et des processus de déréglementation. L’inflation faible, la liquidité abondante, la confiance dans les marchés efficaces et autorégulateurs ont conduit à une perception généralisée de risque faible, incitant les acteurs à une prise accrue de risque. Face aux crises qui s’enchaînent depuis maintenant cinq ans, des mesures de ré-réglementation du système ont été proposées, communément appelées Reformes de Bâle.L’article analyse l’évolution des recommandations de Bâle en lien avec l’évolution économique et des marchés financiers et évalue l’impact de ces dernières sur le secteur bancaire roumain.

Impact, en ce qui a trait à l'économie et à la santé, des politiques ...

International Development Research Centre (IDRC) Digital Library (Canada)

Cette recherche évaluera l'effet des politiques fiscales et législatives sur l'état nutritionnel des Sud-Africains et recommandera d'importantes modifications aux politiques. La plus récente étude nationale sur la charge de morbidité (2000) a mesuré l'impact des MNT à la lumière de divers indicateurs tels que le coût financier, ...

Emission intensity in New Zealand manufacturing and the short-run impacts of emissions pricing

International Nuclear Information System (INIS)

Bartleet, Matthew; Iyer, Kris; Numan-Parsons, Elisabeth

2010-01-01

This paper reports the greenhouse gas (GHG) emission intensity of the New Zealand (NZ) manufacturing sector at a combination of industry group and class levels (sub-sectors). The short-run impacts of a price on emissions are investigated with a focus on exporting activities. Sub-sectors that could be materially impacted by an expected range of emissions prices accounted for slightly over 9% of national gross domestic product. It is found that there is much variability of emission intensity within manufacturing and even within sub-sectors. An assessment of trade intensities further indicates that several emissions-intensive activities are also export-intensive. These activities are at most risk of losing competitiveness in the short-run if they are subjected to a price on GHG emissions that their competitors in other countries are not. Emissions reduction policies must take account of trade competitiveness imperatives if NZ is to meet its international GHG emissions target while maintaining manufacturing sector competitiveness. - Research Highlights: →Estimates initial short-term competitiveness impacts of ETS on NZ manufacturing. →Materiality of impacts determined based on firm level emissions and export intensity. →Results suggest that food processing sub-sectors are likely to be most impacted. →Iron and steel processing, and paper and pulp manufacture are impacted as well. →Cumulative GDP share of materially affected sub-sectors slightly over 9%.

Implementing a system of emissions trading to manage GHGs; La mise en oeuvre des systemes de quotas d'emission echangeables dans la gestion des emissions de GES

Energy Technology Data Exchange (ETDEWEB)

Webster, A. [Sherbrooke Univ., PQ (Canada)

2005-06-01

The exact geographical location of greenhouse gas (GHG) emissions has no bearing on climate change. In this context the Kyoto Protocol recognizes mechanisms of flexibility for countries to attain their GHG emissions reductions. Emission trading takes advantage of this flexibility, allowing GHGs to be sold, traded, or stockpiled. An emission quota allows the owner of an energy facility to emit a certain amount of GHGs throughout the year. If this quota is not used, it can be stockpiled for the following year or it could be traded to another enterprise and owner. If the amount of emissions exceeds the initial quotas, facilities can adopt different strategies, such as reducing their GHG purchasing quotas from national enterprises that have reduced their emissions or purchase quotas from international markets. The initial allocation of quotas is an important political decision since it determines the initial distribution of the GHG reduction effort. The establishment of a quota system can contribute to economical competition and can be used to fulfill environmental objectives regarding energy source development. It is also the most effective way to minimize greenhouse gas emissions and the associated environmental impacts. This paper reviewed the regulations regarding the design of the quota system; how the ceiling of emission levels was determined; the criteria for allocating the quotas and the rules for the exchange of emission quotas. Canada and the European countries have expressed interest in this system of emissions trading. 7 refs.

L’impact des privatisations sur la performance des entreprises françaises

OpenAIRE

Michel Albouy; Hassan Obeid

2007-01-01

(VF)Les déficits budgétaires de nombreux pays, la faiblesse des performances financières des entreprises publiques et les développements récents de la recherche en finance incitent de nombreux États à céder leurs entreprises au secteur privé. Après un panorama du mouvement de privatisation dans le monde et particulièrement en France ainsi qu’un exposé des principaux courants théoriques qui confortent ce mouvement, cet article expose les résultats d’une étude empirique réalisée sur les privati...

Aggregate emissions and evaluation of process combinations; Aggregierte Emissionen und Bewertung der Verfahrenskombinationen

Energy Technology Data Exchange (ETDEWEB)

Schwing, E.; Jager, J. [Institut WAR, Darmstadt (Germany). Fachgruppe Abfalltechnik

1998-12-31

Within the framework of the R and D project ``Mechanical-biological waste conditoning in combination with thermal processing of partial waste fractions``, numerous measurements to determine gaseous and liquid emissions were carried out. These measurements reveal the environmental impact of different treatments and different inputs. They further permit to verify the quality of a treatment. Particularly interesting for the purpose of the project were the total emissions of the considered process combinations. The paper reports the outcome of emission measurements and indicates the variants of process combinations for which the emissions were aggregated. First results of the evaluation of gaseous and liquid emissions are given for these variants. (orig.) [Deutsch] Im Zuge des Forschungs- und Entwicklungsvorhabens `Mechanisch-biologische Restmuellbehandlung unter Einbindung thermischer Verfahren fuer Teilfraktionen` sind zahlreiche Emissionsmessungen bezueglich der luft- und wasserseitigen Emissionen durchgefuehrt worden. Die Ergebnisse dieser Messungen geben Aufschluss ueber die Umweltauswirkungen der verschiedenen Behandlungsverfahren bei unterschiedlichem Input. Des weiteren kann durch sie die Guete des Prozesses ueberprueft werden. Im Projekt interessant sind aber insbesondere die Gesamtemissionen der betrachteten Verfahrenskombinationen. Im folgenden werden die durchgefuehrten Emissionsmessungen und die Varianten der Verfahrenskombinationen, fuer die die Emissionen aggregiert wurden, dargestellt. Dnach werden erste Ergebnisse der Bewertung der luft- und wasserseitigen Emissionen fuer diese Varianten praesentiert. (orig.)

The impact of uncertainty on optimal emission policies

Science.gov (United States)

Botta, Nicola; Jansson, Patrik; Ionescu, Cezar

2018-05-01

We apply a computational framework for specifying and solving sequential decision problems to study the impact of three kinds of uncertainties on optimal emission policies in a stylized sequential emission problem.We find that uncertainties about the implementability of decisions on emission reductions (or increases) have a greater impact on optimal policies than uncertainties about the availability of effective emission reduction technologies and uncertainties about the implications of trespassing critical cumulated emission thresholds. The results show that uncertainties about the implementability of decisions on emission reductions (or increases) call for more precautionary policies. In other words, delaying emission reductions to the point in time when effective technologies will become available is suboptimal when these uncertainties are accounted for rigorously. By contrast, uncertainties about the implications of exceeding critical cumulated emission thresholds tend to make early emission reductions less rewarding.

Emissions and Air Quality Impacts of Freight Transportation

Science.gov (United States)

Bickford, Erica

Diesel freight vehicles (trucks + trains) are responsible for 20% of all U.S. nitrogen oxide (NOx) and 3% of fine particulate (PM2.5) emissions - pollutants that are harmful to human health. Freight tonnage is also projected to double over the next several decades, reaching 30 billion tons by 2050, increasing freight transport activity. Air quality impacts from increased activity, trade-offs between activity and vehicle technology improvements, as well as where to make infrastructure investments that encourage sustainable freight growth, are important considerations for transportation and air quality managers. To address these questions, we build a bottom-up roadway-by-roadway freight truck inventory (WIFE) and employ it to quantify emissions impacts of swapping biodiesel blends into the Midwest diesel freight truck fleet, and investigate emissions and air quality impacts of truck-to-rail freight modal shifts in the Midwest. We also evaluate the spatial and seasonal freight performance of WIFE modeled in a regional photochemical model (CMAQ) against satellite retrievals of nitrogen dioxide (NO2) from the Ozone Monitoring Instrument (OMI). Results show that spatial and seasonal distribution of biodiesel affects regional emissions impacts. Summer high-blend deployment yields a larger annual emissions reduction than year-round low-blend deployment, however, technological improvements in vehicle emissions controls between 2009 and 2018 dwarf the impacts of biodiesel. Truck-to-rail modal shift analysis found 40% of daily freight truck VMT could be shifted to rail freight, causing a 26% net reduction in NOx emissions, and 31% less carbon dioxide (CO2) emissions. Despite significant emissions impacts, air quality modeling results showed mostly localized near roadway air quality improvements, with small regional net changes; yet, federal regulation of CO2 emissions and/or rising costs of diesel fuel could motivate shifting freight to more fuel efficient rail. Evaluation of

Comparison of fission probabilities with emission of long range particles under the action of slow and fast neutrons on various materials; Probabilites comparees de fission avec emission de particules de long parcours pour divers materiaux sous l'action des neutrons lents et rapides

Energy Technology Data Exchange (ETDEWEB)

Netter, F; Faraggi, H; Garin-Bonnet, A; Julien, J; Corge, C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Turkiewicz, J [Institut de Recherches Nucleaire de Varsovie (Poland)

1958-07-01

The authors describe relative cross-section measurements of fission of the isotopes of uranium and plutonium (more particularly {sup 235}U, {sup 238}U, {sup 239}Pu), with emission of long range particles, under the action of neutrons of various energies: thermal neutrons, pile neutrons, neutrons produced with the Van de Graaff accelerator by reaction of protons on tritium. The measurements are carried out: 1) with the aid of photographic plates, by submitting to the action of the neutrons a layer of fissile material coupled with an Ilford nuclear emulsion of 200 microns; a tin sheet laying between the plate and the layer stops the {alpha} particles and the fission fragments. By an appropriate development the tracks of the long range particles can be distinguished in the emulsion, from the tracks of the recoil protons resulting of fission neutrons, or of the last primary neutrons. For neutrons of energy under 1 MeV, the compared frequency of the tracks of long range particles and of the recoils caused by the fission neutrons gives a measurement of the fission cross-section with emission of long range particles relative to the product of the fission cross-section by the mean number of neutrons emitted by fission. For neutrons of higher energy, one measures only the frequency of the tracks of long range particles, comparatively with the flux of primary neutrons. Some precautions are taken to eliminate the action of thermal neutrons in the measurements with fast neutrons. 2) with the aid of a system of ionization chamber and proportional counter, the rate of coincidence between the impulsions caused by the long range particles and the impulsions provided by one of the fission fragments is measured comparatively with the counting rate of fission fragme (author) [French] Les auteurs decrivent des mesures relatives a la section efficace de fission des isotopes de l'uranium et du plutonium (notamment {sup 235}U, {sup 238}U, {sup 239}Pu) avec emission de particules de long

127 Impact des rejets urbains et industriels sur la qualité des eaux ...

African Journals Online (AJOL)

PR BOKO

scour of surfaces and underground. Keywords :aquifer, hydrochimy, rejections, pollution, El Kantara, Biskra, Algeria. 1. Introduction. La qualité des ..... A case study: Suquıa River Basin Au vue des résultats d'analyses hydrochimique, les concentrations en sulfates dépassent la norme (200-400mg/L). (Cordoba-. Argentina).

Temperature behaviour of photo-emissive films. The case of photo-multipliers used in scintillation counters; Comportement en temperature des couches photoemissives. Cas des photomultiplicateurs utilises dans les compteurs a scintillations

Energy Technology Data Exchange (ETDEWEB)

Ardalan, A H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1966-07-01

This work concerns the changes in the spectral sensitivity of 3 types of normal photo-cathodes (Cs{sub 3}Sb, tri-alkali and bi-alkali without cesium) as a function of temperature. The photo-cathodes of cathodes of commercial photomultipliers (DARIO, E.M.I., R.C.A., A.S.C.O.F.) were used for these tests. The temperature range studied was -25 C to +55 C (except for the bi-alkali photo-cathodes which were tested up to +150 C) and the wave-length range was 3250 to 7000 angstrom. After a brief review of photo-electric effect theories, the experimental device is described and the measurement results presented. Finally, an interpretation of these results is proposed. For the normal range of scintillator emission, i.e. between 3000 and 5000 angstroms (Na I (Tl), plastics, anthracene) the temperature coefficient is always negative: -0.15 % C for Cs{sub 3}Sb and up to -0.5 % C for the most temperature-sensitive photo-cathode. Above 5000 angstrom, the temperature coefficient of Cs{sub 3}Sb films becomes positive: +0.5 % C on the overage. The accuracy of the spectral sensitivity measurements is {+-}4 % in absolute value and {+-}1 % in relative value. (author) [French] Cette etude porte sur la variation de la sensibilite spectrale de 3 types de photocathodes usuelles (Cs{sub 3}Sb, trialcalines et bialcalines sans cesium) en fonction de la temperature. Des photocathodes de photomultiplicateurs du commerce (DARIO, E.M.I., R.C.A., A.S.C.O.P.) ont fait l'objet de ces essais. Le domaine examine s'etendait en temperature de -25 C a +55 C (sauf pour les photocathodes bialcalines qui ont ete portees a une temperature de +150 C) et en longueur d'onde de 3250 a 7000 angstrom. Apres un rappel des theories de l'effet photoelectrique, le dispositif experimental est decrit et les resultats des mesures exposes. Enfin, une interpretation de ces resultats est proposee. Dans le domaine de l'emission des scintillateurs usuels, c'est-a-dire entre 3000 et 5000 angstrom (Na I (Tl), plastiques

OGM : vers une évaluation des impacts agri-environnementaux

Directory of Open Access Journals (Sweden)

Icart Jean-Claude

2000-07-01

Full Text Available En 1998, les pouvoirs publics français prononçaient un moratoire de deux ans concernant les autorisations de mise sur le marché des variétés de colza génétiquement modifiées. Cette décision donnait suite aux conclusions de la conférence des citoyens des 20 et 21 juin 1998 à l’Assemblée nationale et aux recommandations de l’Office parlementaire des choix scientifiques et technologiques, fondées sur « les incertitudes liées à la diffusion de transgène dans l’environnement à partir de plantes comme le colza, présentant des risques de croisements avec d’autres espèces ».

Aerosol vertical distribution, new particle formation, and jet aircraft particle emissions in the free troposhere and tropopause region; Vertikalverteilung und Neubildungsprozesse des Aerosols und partikelfoermige Flugzeugemissionen in der freien Troposphaere und Tropopausenregion

Energy Technology Data Exchange (ETDEWEB)

Schroeder, F P

2000-07-01

A contribution to the understanding of natural and anthropogenously induced particle formation as well as aerosol physical transformation processes within the free troposphere (FT) is introduced. Documentation and interpretation of empirical data relevant with respect to possible climatologic impact of anthropogenous aerosol emissions into the atmosphere is presented. The first section describes new technique for high spatial resolution measurements of ultrafine aerosol particles by condensation nucleus counters (CNCs), a necessary prerequisite for the observation of natural particle formation and jet aircraft emissions. The second section illustrates vertical distribution and variability ranges of the aerosol in the FT and the tropopause region (TP). Typical microphysical states of the atmospheric aerosol within the Northern Hemisphere are documented by means of systematic measurements during more than 60 flight missions. Simple mathematical parameterizations of the aerosol vertical distribution and aerosol size distributions are developed. Important aerosol sources within the FT are localized and possible aerosol formation processes are discussed. The third section is focussed on jet-engine particle emissions within the FT and TP. A unique inflight experiment for detection of extremely high concentrations (>10{sup 6} cm{sup -3}) of extremely small (donw to <3 nm) aerosols inside the exhaust plumes of several jet aircraft is described. Particle emission indices and emission-controlling parameters are deduced. Most important topic is the impact of fuel sulfur content of kerosine on number, size and chemical composition of jet particle emissions. Generalized results are parameterized in form of lognormal aerosol particle size distributions. (orig.) [German] Ein Beitrag zum Verstaendnis natuerlicher und anthropogen induzierter Aerosolneubildung sowie physikalischer Aerosolumwandlung in der freien Troposphaere wird vorgestellt. Empirisch gewonnenes Datenmaterial wird

Estimation of greenhouse impacts of continuous regional emissions

Energy Technology Data Exchange (ETDEWEB)

Sinisalo, J. [VTT Energy, Espoo (Finland). Energy Systems

1998-11-01

In this thesis a method to calculate the greenhouse impact of continuous, time-dependent, non-global greenhouse gas emissions is used to estimate the impact of estimated anthropogenic pre-1990 and future (post 1990) emissions of CO{sub 2}, CH{sub 4} and N{sub 2}O from Finland and the Nordic countries. Estimates for the impact of Finnish CFCs and their substitutes and the significance of Finnish forests as carbon sink are also calculated. The method is also used to compare several different wood and peat energy production schemes with fossil fuel use, in terms of caused greenhouse impact. The uncertainty of the results is examined. The greenhouse impact is measured in this thesis as the global mean direct radiative forcing caused by the emissions. Radiative forcing is the driving force behind the climate change and as such it can be used to assess the ensuing climate change. The method is suitable for greenhouse agents that can be considered to be well mixed in the atmosphere (mainly CO{sub 2}, CH{sub 4}, N{sub 2}O and both CFCs and their substitutes). According to the results Finnish greenhouse impact due to anthropogenic CO{sub 2}, CH{sub 4} and N{sub 2}O emissions has increased eight-fold during this century, and will very likely remain higher than current level throughout the next century. The impact of the Nordic countries has followed the same general pattern as Finland. It is likely that the per capita radiative forcing of the Nordic countries will remain above the global average. The uncertainty of the absolute results is quite high due to uncertain knowledge at several stages of the calculation. When the results are used in comparisons (e.g. between emission scenarios, or emissions of different countries), the accuracy of the results increases considerably. (orig.) 54 refs.

Current algebra; Algebre des courants

Energy Technology Data Exchange (ETDEWEB)

Jacob, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-07-01

The first three chapters of these lecture notes are devoted to generalities concerning current algebra. The weak currents are defined, and their main properties given (V-A hypothesis, conserved vector current, selection rules, partially conserved axial current,...). The SU (3) x SU (3) algebra of Gell-Mann is introduced, and the general properties of the non-leptonic weak Hamiltonian are discussed. Chapters 4 to 9 are devoted to some important applications of the algebra. First one proves the Adler- Weisberger formula, in two different ways, by either the infinite momentum frame, or the near-by singularities method. In the others chapters, the latter method is the only one used. The following topics are successively dealt with: semi leptonic decays of K mesons and hyperons, Kroll- Ruderman theorem, non leptonic decays of K mesons and hyperons ( {delta}I = 1/2 rule), low energy theorems concerning processes with emission (or absorption) of a pion or a photon, super-convergence sum rules, and finally, neutrino reactions. (author) [French] La premiere partie de ce cours (trois premiers chapitres), traite des generalites concernant l'algebre de courants. Apres une definition rapide des courants faibles et un rappel de leurs proprietes (hypothese V-A, conservation du courant vecteur, regles de selection, courant axial partiellement conserve,...), l'on introduit l'algebre de Gell-Mann SU (3) x SU (3), et discute les proprietes generales de l'Hamiltonien faible non leptonique. Les chapitres IV a IX sont consacres a des applications importantes de l'algebre des courants. En premier lieu l'on demontre la formule de Adler et Weisberger, par deux methodes differentes, celle dite du repere de moment infini et celle des singularites proches. Cette derniere est seule utilisee dans la suite. Puis, l'on traite successivement les problemes suivants: desintegrations semi-leptoniques des mesons K et des hyperons, theoreme de Kroll-Ruderman, desintegrations non leptoniques des mesons

Améliorer les conditions de vie des jeunes et des femmes en ...

International Development Research Centre (IDRC) Digital Library (Canada)

Améliorer les conditions de vie des jeunes et des femmes en développant la petite entreprise : mesure de l'impact. Durant les années 2000, la croissance économique et l'augmentation des investissements sociaux ont réduit la pauvreté et offert aux populations de l'Amérique latine de multiples débouchés sur le marché du ...

Impacts de la déficience maternelle modérée en fer sur le développement des fonctions auditives et le métabolisme des acides gras et eicosanoïdes de la progéniture

OpenAIRE

Jougleux, Jean-Luc

2015-01-01

Tableau d'honneur de la Faculté des études supérieures et postdorales, 2014-2015 Cette étude a pour objectif de déterminer les impacts de la l’anémie ferriprive (AF) modérée durant la gestation et la lactation, sur les fonctions neurophysiologiques des voies auditives, ainsi que sur les fonctions métaboliques de la progéniture du cochon d’Inde (Cavia porcellus). Elle s’articule selon 2 volets d’études distincts (protocoles 1 et 2), basés tant sur la composition en fer des diètes, que sur l...

Electric vehicles in China: emissions and health impacts.

Science.gov (United States)

Ji, Shuguang; Cherry, Christopher R; J Bechle, Matthew; Wu, Ye; Marshall, Julian D

2012-02-21

E-bikes in China are the single largest adoption of alternative fuel vehicles in history, with more than 100 million e-bikes purchased in the past decade and vehicle ownership about 2× larger for e-bikes as for conventional cars; e-car sales, too, are rapidly growing. We compare emissions (CO(2), PM(2.5), NO(X), HC) and environmental health impacts (primary PM(2.5)) from the use of conventional vehicles (CVs) and electric vehicles (EVs) in 34 major cities in China. CO(2) emissions (g km(-1)) vary and are an order of magnitude greater for e-cars (135-274) and CVs (150-180) than for e-bikes (14-27). PM(2.5) emission factors generally are lower for CVs (gasoline or diesel) than comparable EVs. However, intake fraction is often greater for CVs than for EVs because combustion emissions are generally closer to population centers for CVs (tailpipe emissions) than for EVs (power plant emissions). For most cities, the net result is that primary PM(2.5) environmental health impacts per passenger-km are greater for e-cars than for gasoline cars (3.6× on average), lower than for diesel cars (2.5× on average), and equal to diesel buses. In contrast, e-bikes yield lower environmental health impacts per passenger-km than the three CVs investigated: gasoline cars (2×), diesel cars (10×), and diesel buses (5×). Our findings highlight the importance of considering exposures, and especially the proximity of emissions to people, when evaluating environmental health impacts for EVs.

Perceptions locales de la manifestation des changements ...

African Journals Online (AJOL)

SARAH

. PRPR. ERMA. DC. UD cluster 1 cluster 2. Pauvres. Riches et moyens. Figure 4. Positionnement des classes d'impacts socio-économiques des changements climatiques dans un système d'axes de l'analyse factorielle des ...

Répartition des paramètres physico-chimiques et métalliques des ...

African Journals Online (AJOL)

ibaa

eaux usées modifient la composition physico-chimique des eaux salines des côtes dakaroises jusqu'à 40 m du point de rejets. ... qualité biologique et du degré de la pollution de ce milieu. ..... L'ammoniac d'Origine Agricole : impacts sur la ...

Modeling of pollutant emissions from road transport; Modelisation des emissions de polluants par le transport routier

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

COPERT III (computer programme to calculate emissions from road transport) is the third version of an MS Windows software programme aiming at the calculation of air pollutant emissions from road transport. COPERT estimates emissions of all regulated air pollutants (CO, NO{sub x}, VOC, PM) produced by different vehicle categories as well as CO{sub 2} emissions on the basis of fuel consumption. This research seminar was organized by the French agency of environment and energy mastery (Ademe) around the following topics: the uncertainties and sensitiveness analysis of the COPERT III model, the presentation of case studies that use COPERT III for the estimation of road transport emissions, and the future of the modeling of road transport emissions: from COPERT III to ARTEMIS (assessment and reliability of transport emission models and inventory systems). This document is a compilation of 8 contributions to this seminar and dealing with: the uncertainty and sensitiveness analysis of the COPERT III model; the road mode emissions of the ESCOMPTE program: sensitivity study; the sensitivity analysis of the spatialized traffic at the time-aggregation level: application in the framework of the INTERREG project (Alsace); the road transport aspect of the regional air quality plan of Bourgogne region: exhaustive consideration of the road network; intercomparison of tools and methods for the inventory of emissions of road transport origin; evolution of the French park of vehicles by 2025: new projections; application of COPERT III to the French context: a new version of IMPACT-ADEME; the European ARTEMIS project: new structural considerations for the modeling of road transport emissions. (J.S.)

Impact of policies and measures devoted to the abatement of greenhouse gas emissions; L'impact des politiques et mesures destinees a reduire les emissions de gaz a effet de serre

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

This document is the proceedings of the 7. session of the series of conferences on energy policies jointly organized by the general commission of national development and the general direction of energy and raw materials (DGEMP). A first part is devoted to the presentation of the report entitled 'greenhouse effect: economic modeling and public decision'. This report presents the work carried out for the building of a reference scenario for the evaluation of the expected impact of policies and measures on the evolution of CO{sub 2} emissions. A second part gives some comments about the cost-benefit impacts of environmental policies and the last part summarizes the interventions of some of the participants during the debates. (J.S.)

Environmental Impact of Munition and Propellant Disposal (Impact Environnemental de l’Elimination des Munitions et des Combustibles)

Science.gov (United States)

2010-02-01

the Future of Demil 3-29 3.4.2 Poster Session 3-32 3.4.2.1 The Situation in Lithuania: The Studies on the Explosive Contamination, 3-32 Their Toxic...Presentations and Documents Supporting Capability Assessments A-1 Annex B – Presentations, Paper/ Posters and Videos from the Sofia Meeting B-1 Annex C...sur l’environnement. La réunion a inclus des participants provenant de l’OTAN et des partenaires dont la Russie et la Géorgie. Les sessions étaient

Present day engines pollutant emissions: proposed model for refinery bases impact; Emissions de polluants des moteurs actuels: modelisation de l'impact des bases de raffinage

Energy Technology Data Exchange (ETDEWEB)

Hochart, N.; Jeuland, N.; Montagne, X. [Institut Francais du Petrole (IFP), Div. Techniques d' Applications Energetiques, 92 - Rueil-Malmaison (France); Raux, S. [Institut Francais du Petrole (IFP), Div. Techniques d' Applications Energetiques, Centre d' Etudes et de Developpement Industriel, Rene Navarre, 69 - Vernaison (France); Belot, G.; Cahill, B. [PSA-Peugiot-Citroen, 92 - La Garenne-Colombes (France); Faucon, R.; Petit, A. [Renault, 91 - Lardy (France); Michon, S. [Renault Trucks Powertrain, 69 - Saint Priest (France)

2003-07-01

Air quality improvement, especially in urban areas, is one of the major concerns for the coming years. For this reason, car manufacturers, equipment manufacturers and refiners have explored development issues to comply with increasingly severe anti-pollution requirements. In such a context, the identification of the most promising improvement options is essential. A research program, carried out by IFP (Institut francais du petrole), and supported by the French Ministry of Industry, PSA-Peugeot-Citroen, Renault and RVI (Renault Vehicules Industriels), has been built to study this point. It is based on a 4-year program with different steps focused on new engine technologies which will be available in the next 20 years in order to answer to more and more severe pollutant and CO{sub 2} emissions regulations. This program is divided into three main parts: the first one for Diesel car engines, the second for Diesel truck engines and the third for spark ignition engines. The aim of the work reported here is to characterize the effect of fuel formulation on pollutant emissions and engine tuning for different engine technologies. The originality of this study is to use refinery bases as parameters and not conventional physical or chemical parameters. The tested fuels have been chosen in order to represent the major refinery bases expected to be produced in the near future. These results, expressed with linear correlations between fuel composition and pollutant emissions, will help to give a new orientation to refinery tool. The engines presented in this publication are, for spark ignition engines, an EuroII lean-burn engine (Honda VTEC which equips the Honda Civic) and an EuroIII 1.8 l stoichiometric-running Renault engine which equips the Laguna vehicles, and, for diesel engines, an EuroII Renault Laguna 2.2 l indirect injection diesel engine and an EuroII RVI truck engine. For the fuel formulation, an original approach is proposed: while the classical studies are based

Impact des Propriétés Mécaniques, Géométriques et thermiques des ...

African Journals Online (AJOL)

AKA Boko

Avecε , la déformation, α le coefficient de dilatation thermique, T. ∆ l'écart de température, E, I et A le module d'élasticité, le moment quadratique de la section des éléments substrats et la section des éléments. L'équilibre des moments dans la structure renforcée donne l'équation 13: (). () () ()[. ]a. T. tyyxNxMxM. xM. +. +. +. +.

Investigating Time-Varying Drivers of Grid Project Emissions Impacts

Energy Technology Data Exchange (ETDEWEB)

Barrett, Emily L.; Thayer, Brandon L.; Pal, Seemita; Studarus, Karen E.

2017-11-15

The emissions consequences of smart grid technologies depend heavily on their context and vary not only by geographical location, but by time of year. The same technology operated to meet the same objective may increase the emissions associated with energy generation for part of the year and decrease emissions during other times. The Grid Project Impact Quantification (GridPIQ) tool provides the ability to estimate these seasonal variations and garner insight into the time-varying drivers of grid project emissions impacts. This work leverages GridPIQ to examine the emissions implications across years and seasons of adding energy storage technology to reduce daily peak demand in California and New York.

Impact écotoxicologique de mélanges de pesticides sur des fonctions microbiennes des sols : apport d’une prise en compte écologique dans l’évaluation des risques

OpenAIRE

Devers-Lamrani, Marion; Rouard, Nadine; Cheviron, Nathalie; Grondin, Virginie; Martin-Laurent, Fabrice

2015-01-01

L’utilisation de pesticides permet d’assurer la qualité de la production végétale mais elle contribue à la contamination des sols et des eaux et produit des effets sur des organismes noncibles. L’évaluation des risques requièrent actuellement une meilleure prise en compte des effets des pesticides sur le fonctionnement des écosystèmes. Or, les démarches et indicateurs classiques manquent de représentativité écologique. La fonction microbienne de biodégradation des pesticides est essentielle c...

Effet sur la compétitivité des réglementations relatives à la gestion des effluents

DEFF Research Database (Denmark)

Andersen, Mikael Skou

2004-01-01

Grâce à un regard approfondi sur le secteur laitier dans les pays de l'OCDE, cette étude permet de mieux analyser l'impact des subventions à l'agriculture et des politiques de l'environnement sur l'environnement et sur la compétitivité internationale des produits laitiers. Ce chapitre étudie les ...

Analyzing impact factors of CO2 emissions using the STIRPAT model

International Nuclear Information System (INIS)

Fan Ying; Liu Lancui; Wu Gang; Wei Yiming

2006-01-01

Using the STIRPAT model, this paper analyzes the impact of population, affluence and technology on the total CO 2 emissions of countries at different income levels over the period 1975-2000. Our main results show at the global level that economic growth has the greatest impact on CO 2 emissions, and the proportion of the population between ages 15 and 64 has the least impact. The proportion of the population between 15 and 64 has a negative impact on the total CO 2 emissions of countries at the high income level, but the impact is positive at other income levels. This may illustrate the importance of the 'B' in the 'I = PABT'; that is to say that different behavior fashions can greatly influence environmental change. For low-income countries, the impact of GDP per capita on total CO 2 emissions is very great, and the impact of energy intensity in upper-middle income countries is very great. The impact of these factors on the total CO 2 emissions of countries at the high income level is relatively great. Therefore, these empirical results indicate that the impact of population, affluence and technology on CO 2 emissions varies at different levels of development. Thus, policy-makers should consider these matters fully when they construct their long-term strategies for CO 2 abatement

Le Phénomène Wolf-Rayet au Sein des Etoiles chaudes de Populations I et II: Histoire des Vents stellaires et Impact sur la Structure nébulaire circumstellaire

Science.gov (United States)

Grosdidier, Yves

2000-12-01

Les spectres des étoiles Wolf-Rayet pop. I (WR) présentent de larges raies en émission dues à des vents stellaires chauds en expansion rapide (vitesse terminale de l'ordre de 1000 km/s). Le modèle standard des étoiles WR reproduit qualitativement le profil général et l'intensité des raies observées. Mais la spectroscopie intensive à moyenne résolution de ces étoiles révèle l'existence de variations stochastiques dans les raies (sous-pics mobiles en accélération échelles de temps: environ 10-100 min.). Ces variations ne sont pas comprises dans le cadre du modèle standard et suggèrent une fragmentation intrinsèque des vents. Cette thèse de doctorat présente une étude de la variabilité des raies spectrales en émission des étoiles WR pop. II; la question de l'impact d'un vent WR fragmenté sur le milieu circumstellaire est aussi étudiée: 1) à partir du suivi spectroscopique intensif des raies CIIIl5696 et CIVl5801/12, nous analysons quantitativement (via le calcul des Spectres de Variance Temporelle) les vents issus de 5 étoiles centrales de nébuleuses planétaires (NP) galactiques présentant le phénomène WR; 2) nous étudions l'impact de la fragmentation des vents issus de deux étoiles WR pop. I sur le milieu circumstellaire via: i) l'imagerie IR (NICMOS2/HST) de WR 137, et ii) l'imagerie H-alpha (WFPC2/HST) et l'interférométrie Fabry-Perot H-alpha (SIS-CFHT) de la nébuleuse M 1-67 (étoile centrale: WR 124). Les principaux résultats sont les suivants: VENTS WR POP. II: (1) Nous démontrons la variabilité spectroscopique intrinsèque des vents issus des noyaux de NP HD 826 ([WC 8]), BD +30 3639 ([WC 9]) et LSS 3169 ([WC 9]), observés durant respectivement 22, 15 et 1 nuits, et rapportons des indications de variabilité pour les noyaux [WC 9] HD 167362 et He 2-142. Les variabilités de HD 826 et BD +30 3639 apparaissent parfois plus soutenues (``bursts'' qui se maintiennent durant plusieurs nuits); (2) La cinématique des sous

Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

Energy Technology Data Exchange (ETDEWEB)

Nordemann, D. [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1966-07-01

The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

Gamma-emissions of some meteorites and terrestrial rocks. Evaluation of lunar soil radioactivity; Emissions gamma de quelques meteorites et roches terrestres. Evaluation de la radioactivite du sol lunaire

Energy Technology Data Exchange (ETDEWEB)

Nordemann, D [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1966-07-01

The gamma-emissions of some terrestrial rocks and of the following meteorites: Bogou, Eagle-Station, Granes, and Dosso were studied by quantitative low background gamma spectrometry. These measurements and their interpretation lead to the evaluation of the possible gamma-emissions of several models of lunar soils. (author) [French] Les emissions gamma des meteorites Bogou, Eagle-Station, Granes et Dosso et de quelques roches terrestres ont ete etudiees par spectrometrie gamma quantitative a faible mouvement propre. Ces mesures et leur interpretation permettent d'evaluer les principales contributions des emissions gamma du sol lunaire pour des modeles de compositions possibles variees. (auteur)

Emission metrics for quantifying regional climate impacts of aviation

Directory of Open Access Journals (Sweden)

M. T. Lund

2017-07-01

Full Text Available This study examines the impacts of emissions from aviation in six source regions on global and regional temperatures. We consider the NOx-induced impacts on ozone and methane, aerosols and contrail-cirrus formation and calculate the global and regional emission metrics global warming potential (GWP, global temperature change potential (GTP and absolute regional temperature change potential (ARTP. The GWPs and GTPs vary by a factor of 2–4 between source regions. We find the highest aviation aerosol metric values for South Asian emissions, while contrail-cirrus metrics are higher for Europe and North America, where contrail formation is prevalent, and South America plus Africa, where the optical depth is large once contrails form. The ARTP illustrate important differences in the latitudinal patterns of radiative forcing (RF and temperature response: the temperature response in a given latitude band can be considerably stronger than suggested by the RF in that band, also emphasizing the importance of large-scale circulation impacts. To place our metrics in context, we quantify temperature change in four broad latitude bands following 1 year of emissions from present-day aviation, including CO2. Aviation over North America and Europe causes the largest net warming impact in all latitude bands, reflecting the higher air traffic activity in these regions. Contrail cirrus gives the largest warming contribution in the short term, but remain important at about 15 % of the CO2 impact in several regions even after 100 years. Our results also illustrate both the short- and long-term impacts of CO2: while CO2 becomes dominant on longer timescales, it also gives a notable warming contribution already 20 years after the emission. Our emission metrics can be further used to estimate regional temperature change under alternative aviation emission scenarios. A first evaluation of the ARTP in the context of aviation suggests that further work to account

Impacts de l'utilisation des Engrais chimiques sur les cultures ...

African Journals Online (AJOL)

L'analyse des résultats a montrée que Solanum macrocarpum et amarantus hybridus sont les légumes les plus cultivés respectivement 69% et 21% à cause de leurs préférences dans l'alimentation des consommateurs.Les proportions des maraîchers utilisant les engrais chimiques ou non ou encore les deux couplés sont ...

L’impact des biocarburants sur l’effet de serre

Directory of Open Access Journals (Sweden)

Poitrat Etienne

2002-09-01

Full Text Available Selon les statistiques de l’Observatoire de l’Énergie [1], la France a consommé 267 Mtep (tonnes équivalent pétrole d’énergie primaire en 2001, ou 269 Mtep avec correction climatique. Cette consommation comprend 145,6 Mtep sous forme d’énergie fossile (tableau 1. Les émissions corrigées du seul CO2 correspondant à l’énergie primaire consommée ont été entre août 2001 et juillet 2002, de 109 Mt de carbone par an [2]. Les énergies renouvelables (EnR totales utilisées en France sont d’environ 28 Mtep/an, dont 16,1 tep sont produits par les grands barrages hydro-électriques. Les autres EnR sont les bioénergies (11,9 Mtep/an et les énergies restantes, sont la géothermie, le solaire, l’éolien et la petite hydraulique [3]. En Europe, la France occupe la 5e place avec 11,5 % d’énergie renouvelable consommée après la Suède (26,7 %, l’Autriche (23,3 %, la Finlande (20,9 % et le Portugal (16,9 % [4]. D’autre part, la réserve mondiale prouvée des énergies fossiles représente au rythme actuel de consommation, qui est de 77 % de l’énergie totale consommée (tableau 2, environ 45 ans pour le pétrole, 60 ans pour le gaz et 220 à 250 ans pour le charbon. Afin de réduire les émissions de carbone fossile issues de la combustion des 77 % des énergies fossiles utilisées, il est nécessaire de réduire les consommations d’énergie par des économies et l’amélioration des rendements, de développer les énergies renouvelables et les technologies de séquestration du carbone. En France, les transports dépendent à plus de 95 % des hydrocarbures, non renouvelables, dont l’utilisation a une part déterminante (24 % dans l’émission des gaz à effet de serre. Le transport routier représente 81 % de la consommation énergétique du secteur. L’effet de serre se manifeste par un réchauffement de la température de l’air (+ 0,5 °C/100 ans et des océans (+ 0,3 °C/30 ans, avec une augmentation de la

La formation continue des enseignants aux TICE. Impact sur les contextes locaux

OpenAIRE

Villemonteix , Francois

2004-01-01

La formation continue des enseignants du premier degré dans le domaine des TICE a pour ambition de participer à l'émergence de nouvelles postures professionnelles intégrant l'ordinateur en présence des élèves. Comment les dispositifs actuels de formation participent-t-ils à l'accomplissement de cette tâche, compte tenu de la variété des contextes personnels et professionnels des publics enseignants ? Cette contribution apporte des éléments de réflexion sur le rôle joué par l'action de formati...

Assessment of emission trading impacts on competitive electricity market price

DEFF Research Database (Denmark)

Singh, S.N.; Saxena, D.; Østergaard, Jacob

2011-01-01

analyzes the impact of electricity prices in the competitive electricity markets having a uniform market clearing price mechanism. Findings - It is found that the electricity prices depend on the system loading, generation mix, etc. at a particular hour. Various emission trading instruments are discussed...... side emission trading impact on electricity prices in the competitive power market. Design/methodology/approach - Various schemes are suggested and are being implemented to achieve this objective. It is expected that electricity price will increase due to imposition of emission taxes. This paper...... with a special emphasis on the European market. Research limitations/implications - Block bidding of the suppliers is considered whereas the demand is assumed to be inelastic. Originality/value - The emission trading impacts are analyzed on a simple example....

La revolution des savants

CERN Document Server

Chavanne, A

1989-01-01

Premiere cassette : - 1666 : impact de la creation de l'Academie des Sciences par Colbert, trente ans apres le proces de Galile, et au moment des disparitions de Pascal, Descartes et Fermat. Elle dirigee par le hollandais Huyggens jusqu'a sa fuite de France au moment de la revocation de l'Edit de Nantes. - 1750 : l'Encyclopedie (ou "Dictionnaire raisonne des Sciences, des Arts et des Metiers") de Diderot et d'Alembert, soutenus par Malherbes, Buffon, Condorcet et Rousseau. - 1789 : Revolution francaise. - 8 aout 1793 : l'Assemblee, par une declaration de Marat, dissout l'Academie des Sciences. Celle-ci continue cependant ses travaux pour les poids et mesures jusqu'en 1795. - la Terreur : la condamnation a mort, pas au nom d'une "Revolution qui n'a pas besoin de savants" mais pour d'autres raisons, de trois grands hommes de science : Lavoisier, Bailly et Condorcet. - 1793-1794 : Au printemps 93, le Comite de Salut Publique s'inquiete du demi-million de soldats etrangers de toutes les pays frontaliers qui essai...

Sécurité au-delà des mythes et des croyances

CERN Multimedia

CERN. Geneva

2010-01-01

La pire des failles de sécurité est l'impression de sécurité. Le décalage entre la compréhension que l’on a des technologies utilisées, et leurs potentiels réels, ainsi que l'impact potentiellement négatif qu'elles peuvent avoir sur nos vies, n'est pas toujours compris, ou pris en compte par la plupart d'entre-nous. On se contente de nos perceptions pour ne pas avoir à se confronter à la réalité... Alors qu'en est-il vraiment ? En matière de sécurité qui de l'humain ou des technologies a le contrôle ?

Impacts des effluents liquides industriels sur l'environnement urbain ...

African Journals Online (AJOL)

industrialisation l'un des maillons essentiels du développement, après le succès de l'agriculture. Mais la mise en oeuvre de cette politique pose parfois des problèmes d'environnement à Abidjan. La présente étude a pour objectif principal ...

Impact of neighborhood design on energy performance and GHG emissions

International Nuclear Information System (INIS)

Hachem, Caroline

2016-01-01

Highlights: • Energy use and GHG emissions of different neighborhood designs are investigated. • Improving buildings energy performance reduces energy use and GHG emissions by 75%. • Density as isolated factor has limited effect on transport on per capita basis. • Distance to central business district impacts transport GHG emission significantly. - Abstract: This paper presents an innovative and holistic approach to the analysis of the impact of selected design parameters of a new solar community on its environmental performance, in terms of energy efficiency and carbon footprint (green-house gas (GHG) emissions). The design parameters include energy performance level of buildings, density, type of the neighborhood (mixed-use vs residential), location of the commercial center relative to residential areas and the design of the streets. Energy performance is measured as the balance between overall energy consumption for building operations (assuming an all-electric neighborhood) and electricity generation potential through integration of PV panels on available roof surfaces. Greenhouse gas emissions are those associated with building operations and transport. Results of simulations carried out on prototype neighborhoods located in the vicinity of Calgary, Alberta, Canada indicate that, while adopting high-energy efficiency measures can reduce the buildings’ impact by up to 75% in terms of energy consumption and GHG emissions, transport still has a large environmental impact. The parameters of highest impact on transport and its associated GHG emissions are the design of the neighborhood and the distance to the business center. Density, as isolated parameter, has a modest effect on the selected mode of transportation, in terms of using private or public transportation. While this study relates to a specific location and a range of design assumptions, the methodology employed can serve as a template for evaluating design alternatives of new sustainable

Norwegian gas sales and the impacts on European CO2 emissions

International Nuclear Information System (INIS)

Berg, E.; Boug, P.; Kverndokk, S.

2001-01-01

This paper has studied the impacts on Western European CO 2 emissions of a reduction in Norwegian gas sales. Such impacts are due to changes in energy demand, energy supply, and environmental and political regulations. The gas supply model DYNOPOLY was used to analyse the effects on Russian and Algerian gas exports of a reduction in Norwegian gas supply. The effects on the demand side and the effects of committing to CO 2 targets were analysed using the energy demand model SEEM. If Western European countries commit to their announced CO 2 emissions targets, reduced Norwegian gas sales will have no impact on emissions. The consumption of oil and coal will increase slightly, while the total energy consumption will go down. Also, a reduction in Norwegian gas sales will have only minor impacts on the CO 2 emissions from Western Europe when no emissions regulations are considered

Impact de la mise en places des comités d'audit dans les banques tunisiennes

OpenAIRE

Sonda Marrakchi Chtourou; Sana Ben Hassine

2006-01-01

International audience; Dans le cadre de la présente étude, nous proposons d'investiguer l'impact de la création du comité d'audit sur certains éléments du système de gouvernance des banques tunisiennes. Plus particulièrement, ces éléments concernent le fonctionnement du conseil d'administration, la qualité de l'information financière produite, l'indépendance de l'auditeur interne, la qualité du contrôle interne ainsi que l'étendue des travaux d'audit externe planifiés. A cet effet, l'étude d...

Emissions pathways, climate change, and impacts on California

Science.gov (United States)

Hayhoe, Katharine; Cayan, Daniel; Field, Christopher B.; Frumhoff, Peter C.; Maurer, Edwin P.; Miller, Norman L.; Moser, Susanne C.; Schneider, Stephen H.; Cahill, Kimberly Nicholas; Cleland, Elsa E.; Dale, Larry; Drapek, Ray; Hanemann, R. Michael; Kalkstein, Laurence S.; Lenihan, James; Lunch, Claire K.; Neilson, Ronald P.; Sheridan, Scott C.; Verville, Julia H.

2004-01-01

The magnitude of future climate change depends substantially on the greenhouse gas emission pathways we choose. Here we explore the implications of the highest and lowest Intergovernmental Panel on Climate Change emissions pathways for climate change and associated impacts in California. Based on climate projections from two state-of-the-art climate models with low and medium sensitivity (Parallel Climate Model and Hadley Centre Climate Model, version 3, respectively), we find that annual temperature increases nearly double from the lower B1 to the higher A1fi emissions scenario before 2100. Three of four simulations also show greater increases in summer temperatures as compared with winter. Extreme heat and the associated impacts on a range of temperature-sensitive sectors are substantially greater under the higher emissions scenario, with some interscenario differences apparent before midcentury. By the end of the century under the B1 scenario, heatwaves and extreme heat in Los Angeles quadruple in frequency while heat-related mortality increases two to three times; alpine/subalpine forests are reduced by 50–75%; and Sierra snowpack is reduced 30–70%. Under A1fi, heatwaves in Los Angeles are six to eight times more frequent, with heat-related excess mortality increasing five to seven times; alpine/subalpine forests are reduced by 75–90%; and snowpack declines 73–90%, with cascading impacts on runoff and streamflow that, combined with projected modest declines in winter precipitation, could fundamentally disrupt California's water rights system. Although interscenario differences in climate impacts and costs of adaptation emerge mainly in the second half of the century, they are strongly dependent on emissions from preceding decades. PMID:15314227

Impact des politiques fiscales visant à améliorer la nutrition en ...

International Development Research Centre (IDRC) Digital Library (Canada)

améliorer la nutrition en Afrique du Sud. Prévention des maladies non transmissibles. (PMNT). PROFIL DE PROJET. Le programme Prévention des maladies non transmis- sibles (PMNT) soutient la production de nouvelles connaissances en vue d'inspirer des politiques et des pro- grammes peu coûteux mais susceptibles ...

Influence de la nature des fuels lourds sur la qualité de leur combustion Influence of Heavy Fuel Oil Composition on Particulate Emissions

Directory of Open Access Journals (Sweden)

Feugier A.

2006-11-01

Full Text Available A partir d'études de combustion de fuels lourds numéro 2 effectuées dans une chaudière de 1 MW et dans un foyer de 0,1 MW, on conclut que le résidu de Carbone Conradson (CCR des fuels est un bon indicateur de leur combustibilité, mais qu'il n'est pas suffisant dans tous les cas, c'est-à-dire que pour un même CCR, on peut mesurer des valeurs différentes en indice pondéral. Plusieurs interpréta. tions possibles ont été proposées et vérifiées : a Le résidu de Carbone Conradson, résultat d'une pyrolyse lente, est une procédure qui n'est pas suffisamment représentative des conditions réelles. Or, en soumettant un certain nombre de fuels à une pyrolyse flash (technique de la grille chauffée, on observe une bonne corrélation entre la quantité de résidu résultant et le CCR. Donc, ce dernier reste un bon indicateur de combustibilité. b Pour les fuels ex résidu atmosphérique, ex résidu sous-vide et ex désasphaltage, on détermine de satisfaisantes corrélations entre le CCR et certaines caractéristiques physico-chimiques de la fraction lourde des fuels (point de coupe choisi 450°C : polyaromaticité (mesurée par RMN du Carbone 13, C/H, masse moléculaire. Cependant, les fuels de visco-réduction satisfont à d'autres corrélations, de même que les résidus de vapocraquage. Donc, pour ces classes de fuels, on peut prévoir des anomalies entre indice pondéral et CCR, ce qui est observé dans certains équipements. c On observe que pour une même valeur de CCR, la proportion relative entre fractions légères et fractions lourdes des fuels peut parfois varier très sensiblement avec pour conséquence des modifications dans les cartes de richesse et de température des flammes résultantes, et donc des variations dans les émissions particulaires. L'importance de telles variations dépendra des types de brûleurs et de chambres de combustion dans lesquelles la flamme se développera. On the basis of combustion runs of

Some methods for the detection of fissionable matter; Quelques methodes de detection des corps fissiles

Energy Technology Data Exchange (ETDEWEB)

Guery, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1967-03-01

A number of equipments or processes allowing to detect uranium or plutonium in industrial plants, and in particular to measure solution concentrations, are studied here. Each method has its own field of applications and has its own performances, which we have tried to define by calculations and by experiments. The following topics have been treated: {gamma} absorptiometer with an Am source, detection test by neutron multiplication, apparatus for the measurement of the {alpha} activity of a solution, fissionable matter detection by {gamma} emission, fissionable matter detection by neutron emission. (author) [French] On examine ici plusieurs appareils ou procedes qui permettent de detecter l'uranium ou le plutonium dans les installations industrielles, et en particulier de mesurer les concentrations de solutions. Chacune des methodes a son domaine d'application et ses performances, qu'on a tente de definir par le calcul et par des experiences. Les sujets traites sont les suivants: absorptiometre {gamma} a source d'americium, essais de detection par multiplication neutronique, appareil de mesure de l'activite {alpha} d'une solution, detection des matieres fissiles par leur emission {gamma}, detection des matieres fissiles par leur emission neutronique. (auteur)

Climate Impacts From a Removal of Anthropogenic Aerosol Emissions

Science.gov (United States)

Samset, B. H.; Sand, M.; Smith, C. J.; Bauer, S. E.; Forster, P. M.; Fuglestvedt, J. S.; Osprey, S.; Schleussner, C.-F.

2018-01-01

Limiting global warming to 1.5 or 2.0°C requires strong mitigation of anthropogenic greenhouse gas (GHG) emissions. Concurrently, emissions of anthropogenic aerosols will decline, due to coemission with GHG, and measures to improve air quality. However, the combined climate effect of GHG and aerosol emissions over the industrial era is poorly constrained. Here we show the climate impacts from removing present-day anthropogenic aerosol emissions and compare them to the impacts from moderate GHG-dominated global warming. Removing aerosols induces a global mean surface heating of 0.5-1.1°C, and precipitation increase of 2.0-4.6%. Extreme weather indices also increase. We find a higher sensitivity of extreme events to aerosol reductions, per degree of surface warming, in particular over the major aerosol emission regions. Under near-term warming, we find that regional climate change will depend strongly on the balance between aerosol and GHG forcing.

Impact de la dynamique de peuplement sur la distribution des glossines et des trypanosomoses dans la boucle du Mouhoun (Burkina Faso*

Directory of Open Access Journals (Sweden)

Rouamba J.

2009-03-01

Full Text Available Au Burkina-Faso, la boucle du Mouhoun constitue un foyer historique des trypanosomoses humaines africaines (THA et animales africaines (TAA, transmises par les glossines. Aujourd’hui, la THA semble avoir disparu de cette région après quelques soubresauts dans les années 1970, tandis que la TAA continue de sévir. Afin de mieux comprendre ces évolutions divergentes, nous avons mené une étude géographique basée sur l’analyse de photographies aériennes entre 1952 et 2007, ainsi que d’enquêtes de terrain sur les aspects médicaux, entomologiques et vétérinaires des trypanosomoses. Il apparaît que le paysage de cette région a connu en l’espace d’un siècle des modifications intenses, notamment du fait de l’augmentation des densités de population et des surfaces cultivées, qui n’ont pas été sans conséquences sur le nombre et la distribution des mouches tsé-tsé. Associée à la lutte médicale qui avait permis la stérilisation du réservoir humain de trypanosomes dans les années 1940, cette dégradation paysagère, accompagnée du développement des aménagements hydrauliques et d’évolutions des modalités de migration des hommes et des animaux, semble pouvoir expliquer ces disparités THA/TAA. La mise en évidence de ces facteurs, et leur prise en compte lors d’études ultérieures menées dans d’autres régions, devrait permettre de délimiter des zones d’intervention prioritaires contre les trypanosomoses et leurs vecteurs dans un contexte de lutte internationale contre ces pathologies.

International Oil Price’s Impacts on Carbon Emission in China’s Transportation Industry

Directory of Open Access Journals (Sweden)

Guoxing Zhang

2014-09-01

Full Text Available Purpose: This paper analyses the impact mechanism of international oil price on the industrial carbon emission, and uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry.Design/methodology/approach: This paper chooses five independent variables of GDP, international oil price, private car population, passenger and freight transportation volume as impact factors to investigate industrial carbon emissions, the paper also analyses the impact mechanism of international oil price on the industrial carbon emission, and finally the paper uses the partial least squares regression model to study international oil price’s impact on carbon emissions in China’s transportation industry. With the independent variables’ historical data from 1994 to 2009 as a sample, the fitting of the industry carbon emissions is satisfying. And based on the data of 2011, the paper maintains the private car owning, passenger and freight transportation volume to study international oil prices’ impact on the industry carbon emissions at different levels of GDP.Findings: The results show that: with the same GDP growth, the industry carbon emissions increase with the rise in international oil prices, and vice versa, the industry carbon emissions decrease; and lastly when GDP increases to a certain extent, in both cases of international oil prices’ rise or fall, the industry carbon emissions will go up, and the industry carbon emissions increase even faster while the energy prices are rising.Practical implications: Limit the growth in private-vehicle ownership, change China's transport sector within the next short-term in the structure of energy consumption and put forward China's new energy, alternative energy sources and renewable energy application so as to weaken the dependence on international oil, and indirectly slowdown China's GDP growth rate, which are all possible

Quantification of the Impact of Roadway Conditions on Emissions

Science.gov (United States)

2017-11-01

The scope of this project involved developing a methodology to quantify the impact of roads condition on emissions and providing guidance to assist TxDOT in improving maintenance strategies to reduce gas emissions. The research quantified vehicle ...

Vacuum welding of metals; Soudage des metaux sous vide

Energy Technology Data Exchange (ETDEWEB)

Stohr, J A; Briola, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

This new welding process has been developed by the Commissariat a l'Energie Atomique (CEA) in France. The edges of the work-pieces are melted by the impact of an electron beam produced by an electron gun. Welding is carried out in a vacuum of 10{sup -4} to 10{sup -8} mm of mercury. The welding machine consists, diagrammatically, of: a) a metal enclosure in which a vacuum is produced; b) a cathode for electron emission, a high-voltage generator for accelerating these electrons, a focusing device; c) a mechanical device for moving (rotating) the work-piece. Advantages of the process: 1) possible welding of highly oxidizable metals (e.g. zirconium); 2) fabrication of high-vacuum-sealed metal containers; 3) production of very deeply penetrated welds. Therefore, this new process is particularly advantageous for atomic power applications, the fabrication of electron tubes and, more generally, for all industries in which very special metals are used. (author) [French] Ce procede de soudage a ete recemment mis au point au Commissariat a l'Energie Atomique en France (CEA). Il consiste a utiliser, pour fondre les levres des pieces a souder, l'impact d'un faisceau d'electrons produit par un canon a electrons. Le soudage s'effectue sous un vide de 10{sup -4} a 10{sup -8} mm de mercure. La machine a souder se compose schematiquement: a) d'une enceinte metallique ou l'on fait le vide; b) d'une cathode emettant des electrons, d'un generateur H.T. permettant d'accelerer ces electrons d'un dispositif de focalisation; c) d'un dispositif mecanique permettant le deplacement (rotation) de la piece a souder. Avantages de ce procede: 1) possibilite de souder les metaux tres oxydables (exemple: zirconium); 2) realisation de 'containers' metalliques fermes sous vide pousse; 3) obtention de profondeurs de soudures considerables. Ce nouveau procede est donc particulierement interessant pour l ' energie atomique, la fabrication des tubes electroniques et, en general, toutes les industries

Impact des néo-facteurs de pollution sur la qualité des eaux de la ...

African Journals Online (AJOL)

Les résultats obtenus montrent une pollution importante par les éléments majeurs des Eléments Traces Métalliques (ETM) et des nutriments. Les méthodes utilisées convergent toutes pour confirmer la pollution naturelle caractérisée par les liens existant entre les éléments majeurs et une pollution anthropiques par les ETM ...

determinants de l'adoption et impact des varietes ameliorees sur la ...

African Journals Online (AJOL)

ACSS

C'est ainsi que la recherche a créé des nouvelles variétés ... La recherche en économie de la production agricole a montré que les taux d'adoption et les facteurs influençant la décision des agriculteurs d'adopter une technologie agricole varient fortement entre ..... des agriculteurs sur l'innovation sont fortement liées aux ...

169 Effet des flux d'eau sur la capacité de rétention des marais ...

African Journals Online (AJOL)

DieudoneZ

apport des nutriments charriés par les rivières Lwiro et Cirhanyobwa et déterminer ainsi son impact sur l'efficacité de rétention des polluants par les marais Ciranga et Kabamba. Les échantillons d'eaux récoltés dans les rivières et dans les ...

Les nouvelles formes de la communication autour des projets urbains : modalités, impacts, enjeux pour un débat participatif

Directory of Open Access Journals (Sweden)

Hélène Bailleul

2008-09-01

Full Text Available Dans cet article, nous observons les évolutions que l’usage des nouvelles technologies implique dans la communication autour des projets urbains. Notre analyse des nouvelles modalités qu’Internet a pu importer dans la participation des habitants aux projets urbains (partie 1 nous pousse à observer, plus spécifiquement, les modifications qui ont trait, dans ce contexte, à la nature et au statut de l’information sur l’espace. La démocratisation des techniques de représentation de l’espace par ordinateur (3D, simulation entraîne le recours quasi systématique à des images virtuelles du projet, d’une grande qualité (partie 2, mais dont on ne connaît que très peu les impacts sur la perception et la réception que les habitants font du projet (partie 3.In this article, we observe the evolutions involved by the use of new technology in the communication around urban projects. Our analysis of the new modalities, Internet was able to import in the participation of inhabitants in urban projects (chapter 1 urges us to examine, more specifically, the modifications concerning the nature and the status of the information about space. The democratization of computer-based spatial representation’s tools (3D, simulation entails more and more systematic recourse to virtual images of the project, with high definition (chapter 2. But, nowadays, we still know little about their impacts on the perception and the reception, the inhabitants make of the project (chapter 3.

Relevance of emissions timing in biofuel greenhouse gases and climate impacts.

Science.gov (United States)

Schwietzke, Stefan; Griffin, W Michael; Matthews, H Scott

2011-10-01

Employing life cycle greenhouse gas (GHG) emissions as a key performance metric in energy and environmental policy may underestimate actual climate change impacts. Emissions released early in the life cycle cause greater cumulative radiative forcing (CRF) over the next decades than later emissions. Some indicate that ignoring emissions timing in traditional biofuel GHG accounting overestimates the effectiveness of policies supporting corn ethanol by 10-90% due to early land use change (LUC) induced GHGs. We use an IPCC climate model to (1) estimate absolute CRF from U.S. corn ethanol and (2) quantify an emissions timing factor (ETF), which is masked in the traditional GHG accounting. In contrast to earlier analyses, ETF is only 2% (5%) over 100 (50) years of impacts. Emissions uncertainty itself (LUC, fuel production period) is 1-2 orders of magnitude higher, which dwarfs the timing effect. From a GHG accounting perspective, emissions timing adds little to our understanding of the climate impacts of biofuels. However, policy makers should recognize that ETF could significantly decrease corn ethanol's probability of meeting the 20% GHG reduction target in the 2007 Energy Independence and Security Act. The added uncertainty of potentially employing more complex emissions metrics is yet to be quantified.

Effets des electrons secondaires sur l'ADN

Science.gov (United States)

Boudaiffa, Badia

Les interactions des electrons de basse energie (EBE) representent un element important en sciences des radiations, particulierement, les sequences se produisant immediatement apres l'interaction de la radiation ionisante avec le milieu biologique. Il est bien connu que lorsque ces radiations deposent leur energie dans la cellule, elles produisent un grand nombre d'electrons secondaires (4 x 104/MeV), qui sont crees le long de la trace avec des energies cinetiques initiales bien inferieures a 20 eV. Cependant, il n'y a jamais eu de mesures directes demontrant l'interaction de ces electrons de tres basse energie avec l'ADN, du principalement aux difficultes experimentales imposees par la complexite du milieu biologique. Dans notre laboratoire, les dernieres annees ont ete consacrees a l'etude des phenomenes fondamentaux induits par impact des EBE sur differentes molecules simples (e.g., N2, CO, O2, H2O, NO, C2H 4, C6H6, C2H12) et quelques molecules complexes dans leur phase solide. D'autres travaux effectues recemment sur des bases de l'ADN et des oligonucleotides ont montre que les EBE produisent des bris moleculaires sur les biomolecules. Ces travaux nous ont permis d'elaborer des techniques pour mettre en evidence et comprendre les interactions fondamentales des EBE avec des molecules d'interet biologique, afin d'atteindre notre objectif majeur d'etudier l'effet direct de ces particules sur la molecule d'ADN. Les techniques de sciences des surfaces developpees et utilisees dans les etudes precitees peuvent etre etendues et combinees avec des methodes classiques de biologie pour etudier les dommages de l'ADN induits par l'impact des EBE. Nos experiences ont montre l'efficacite des electrons de 3--20 eV a induire des coupures simple et double brins dans l'ADN. Pour des energies inferieures a 15 eV, ces coupures sont induites par la localisation temporaire d'un electron sur une unite moleculaire de l'ADN, ce qui engendre la formation d'un ion negatif transitoire

A guide for implementation of the European Pollutant Emission Register (EPER) in Germany; Leitfaden zur Umsetzung des Europaeischen Schadstoffemissionsregisters (EPER) in Deutschland

Energy Technology Data Exchange (ETDEWEB)

Kuehne, C.; Striegel, G.

2001-10-01

The report presents specifications for implementing the European Pollutant Emission Register (EPER) in Germany. [German] Gemaess Artikel 15 (3) der Richtlinie 96/61/EG ueber die integrierte Vermeidung und Verminderung der Umweltverschmutzung ('IVU-Richtlinie') veroeffentlicht die Kommission alle drei Jahre ein Verzeichnis der wichtigsten Emissionen und ihrer Quellen anhand der von den Mitgliedstaaten uebermittelten Informationen. Fuer die Mitgliedstaaten ergibt sich hieraus die Verpflichtung, die erforderlichen Daten zu erheben, auszuwerten und der Europaeischen Kommission zu berichten. In der Entscheidung der Kommission vom 17. Juli 2000 ueber den Aufbau eines Europaeischen Schadstoffemissionsregisters (EPER- 'European Pollutant Emission Register') 2000/479/EG ('EPER-Entscheidung') werden die Anforderungen an Inhalt und Form dieses Verzeichnisses konkretisiert: - Die Mitgliedstaaten berichten der Kommission ueber die Emissionen in die Luft und in das Wasser aus einzelnen Betriebseinrichtungen. Zu berichten sind die Emissionen bestimmter Schadstoffe, die ueber vorgegebenen Schwellenwerten liegen. Das Berichtsformat fuer die Mitgliedstaaten ist im Anhang A2 der EPER-Entscheidung festgelegt. - Der erste Bericht ist im Juni 2003 vorzulegen und soll Angaben ueber Emissionen im Jahr 2001 (bzw. wahlweise 2000 oder 2002) enthalten. Jeder Mitgliedstaat muss zudem einen zusammenfassenden nationalen Uebersichtsbericht erstellen. - Die Europaeische Kommission wird die Emissionsdaten ueber das Internet der Oeffentlichkeit zugaenglich machen. Fuer die Erhebung der fuer das EPER erforderlichen Daten in Deutschland wird ein schrittweises Vorgehen empfohlen: - Am Anfang steht die Identifizierung von Betriebseinrichtungen mit Taetigkeiten nach Anhang I der IVU-Richtlinie. - Angabe des NACE-Kodes der Betriebseinrichtung und Zuordnung der Anhang I-Taetigkeiten (Quellenkategorie) und des NOSE-P-Kodes gemaess Anhang A3 der EPER-Entscheidung. - Festlegung

Integration of Energy Consumption and CO2 Emissions into the DES Tool with Lean Thinking

Science.gov (United States)

Nujoom, Reda; Wang, Qian

2018-01-01

Products are often made by accomplishing a number of manufacturing processes on a sequential flow line which is also known as manufacturing systems. In a traditional way, design or evaluation of a manufacturing system involves a determination or an analysis of the system performance by adjusting system parameters relating to such as system capacity, material processing time, material-handling and transportation and shop-floor layout. Environment related parameters, however, are not considered or considered as separate issues. In the past decade, there has been a growing concern about the environmental protection and governments almost in all over the world enforced certain rules and regulation to promote energy saving and reduce carbon dioxide (CO2) emissions in manufacturing industry. To date, development of a sustainable manufacturing system requires designers who need not merely to apply traditional methods of improving system efficiency and productivity but also examine the environmental issues in production of the developed manufacturing system. Most researchers, however, focused on operational systems, which do not incorporate the effect of environmental factors that may also affect the system performance. This paper presents a research work aiming to addresses these issues in design and evaluation of sustainable manufacturing systems incorporating parameters of energy consumption and CO2 emissions into a DES (discrete event simulation) tool.

Raisons de l'impact majeur des inondations provoquées par les ...

International Development Research Centre (IDRC) Digital Library (Canada)

30 avr. 2012 ... Les inondations de juillet 2010 dans le bassin de l'Indus sont l'une des ... comprend l'un des systèmes d'irrigation de surface les plus importants du monde. ... de revenus, différents actifs et accès à des services (logement sûr, ...

EVALUATION DE L’IMPACT ENVIRONNEMENTAL : Evaluation des impacts du flux de transgènes de tolérance à différents herbicides à large spectre

Directory of Open Access Journals (Sweden)

Astoin Marie-Florence

2000-07-01

Full Text Available Ce texte est tiré du rapport « Introduction de variétés génétiquement modifiées de colza tolérantes à différents herbicides : évaluation des impacts agro-environnementaux et propositions de scénarios de gestion » établi par le Cetiom dans le cadre du moratoire sur les variétés génétiquement modifiées de colza. Les auteurs se réservent la possibilité d’ici publication définitive du rapport d’apporter des modifications à ce texte.

External costs of atmospheric Pb emissions: valuation of neurotoxic impacts due to inhalation

DEFF Research Database (Denmark)

Pizzol, Massimo; Thomsen, Marianne; Frohn, Lise

2010-01-01

The Impact Pathway Approach (IPA) is an innovative methodology to establish links between emissions, related impacts and monetary estimates. Only few attempts have so far been presented regarding emissions of metals; in this study the external costs of airborne lead (Pb) emissions are assessed...... using the IPA. Exposure to Pb is known to provoke impacts especially on children's cognition. As cognitive abilities (measured as IQ, intelligence quotient) are known to have implications for lifetime income, a pathway can be established leading from figures for Pb emissions to the implied loss...

Succession managériale et richesse des actionnaires: le rôle de l’origine du successeur et des facteurs de contingence structurelle

Directory of Open Access Journals (Sweden)

Léopold DJOUTSA Wamba

2014-03-01

Full Text Available L’objectif de cet article est tout d’abord, de déterminer l’impact de la succession managériale sur la richesse des actionnaires, ensuite de vérifier si la prise en compte des facteurs de contingence structurelle en fonction de l’origine du successeur peut modifier cet impact. A travers une méthodologie d’études d’événement, d’association et de comparaison sur des données collectées entre mars et octobre sur un échantillon de 50 cas de succession managériale sur la période 1990 à 2004 dans les sociétés anonymes au Cameroun, les résultats ont montré d’une part que l’impact global de la succession managériale sur la richesse des actionnaires est négatif et significatif; et d’autre part que cet impact varie significativement avec la prise en compte des facteurs de contingence structurelle (la taille de l’entreprise, la performance de l’entreprise avant la succession et l’environnement de l’entreprise en fonction de l’origine du successeur. Ces résultats suggèrent d’une part que cet impact négatif est amplifié par la taille de l’entreprise, la performance de l’entreprise, la variabilité de l’entreprise et atténué par la complexité de l’environnement.

Impact de la gestion des ressources humaines sur la survie des ...

African Journals Online (AJOL)

A partir d'un indice composite, l'indice de gestion des ressources humaines ... (iv) la gestion de la performance, et (v) la formation et le développement du ... Même si à cause du type d'étude quasi-expérimentale réalisée (avant-après), nous ne ... GRH d'une organisation doit aussi devenir un objectif chiffré du management.

Regional air quality impacts of future fire emissions in Sumatra and Kalimantan

Science.gov (United States)

Marlier, Miriam E.; DeFries, Ruth S.; Kim, Patrick S.; Gaveau, David L. A.; Koplitz, Shannon N.; Jacob, Daniel J.; Mickley, Loretta J.; Margono, Belinda A.; Myers, Samuel S.

2015-05-01

Fire emissions associated with land cover change and land management contribute to the concentrations of atmospheric pollutants, which can affect regional air quality and climate. Mitigating these impacts requires a comprehensive understanding of the relationship between fires and different land cover change trajectories and land management strategies. We develop future fire emissions inventories from 2010-2030 for Sumatra and Kalimantan (Indonesian Borneo) to assess the impact of varying levels of forest and peatland conservation on air quality in Equatorial Asia. To compile these inventories, we combine detailed land cover information from published maps of forest extent, satellite fire radiative power observations, fire emissions from the Global Fire Emissions Database, and spatially explicit future land cover projections using a land cover change model. We apply the sensitivities of mean smoke concentrations to Indonesian fire emissions, calculated by the GEOS-Chem adjoint model, to our scenario-based future fire emissions inventories to quantify the different impacts of fires on surface air quality across Equatorial Asia. We find that public health impacts are highly sensitive to the location of fires, with emissions from Sumatra contributing more to smoke concentrations at population centers across the region than Kalimantan, which had higher emissions by more than a factor of two. Compared to business-as-usual projections, protecting peatlands from fires reduces smoke concentrations in the cities of Singapore and Palembang by 70% and 40%, and by 60% for the Equatorial Asian region, weighted by the population in each grid cell. Our results indicate the importance of focusing conservation priorities on protecting both forested (intact or logged) peatlands and non-forested peatlands from fire, even after considering potential leakage of deforestation pressure to other areas, in order to limit the impact of fire emissions on atmospheric smoke concentrations and

Regional air quality impacts of future fire emissions in Sumatra and Kalimantan

International Nuclear Information System (INIS)

Marlier, Miriam E; DeFries, Ruth S; Kim, Patrick S; Koplitz, Shannon N; Jacob, Daniel J; Gaveau, David L A; Mickley, Loretta J; Margono, Belinda A; Myers, Samuel S

2015-01-01

Fire emissions associated with land cover change and land management contribute to the concentrations of atmospheric pollutants, which can affect regional air quality and climate. Mitigating these impacts requires a comprehensive understanding of the relationship between fires and different land cover change trajectories and land management strategies. We develop future fire emissions inventories from 2010–2030 for Sumatra and Kalimantan (Indonesian Borneo) to assess the impact of varying levels of forest and peatland conservation on air quality in Equatorial Asia. To compile these inventories, we combine detailed land cover information from published maps of forest extent, satellite fire radiative power observations, fire emissions from the Global Fire Emissions Database, and spatially explicit future land cover projections using a land cover change model. We apply the sensitivities of mean smoke concentrations to Indonesian fire emissions, calculated by the GEOS-Chem adjoint model, to our scenario-based future fire emissions inventories to quantify the different impacts of fires on surface air quality across Equatorial Asia. We find that public health impacts are highly sensitive to the location of fires, with emissions from Sumatra contributing more to smoke concentrations at population centers across the region than Kalimantan, which had higher emissions by more than a factor of two. Compared to business-as-usual projections, protecting peatlands from fires reduces smoke concentrations in the cities of Singapore and Palembang by 70% and 40%, and by 60% for the Equatorial Asian region, weighted by the population in each grid cell. Our results indicate the importance of focusing conservation priorities on protecting both forested (intact or logged) peatlands and non-forested peatlands from fire, even after considering potential leakage of deforestation pressure to other areas, in order to limit the impact of fire emissions on atmospheric smoke concentrations

Acoustic emission measurement during instrumented impact tests

International Nuclear Information System (INIS)

Crostack, H.A.; Engelhardt, A.H.

1983-01-01

Results of instrumented impact tests are discussed. On the one hand the development of the loading process at the hammer tup was recorded by means of a piezoelectric transducer. This instrumentation supplied a better representation of the load versus time than the conventional strain gauges. On the other hand the different types of acoustic emission occurring during a test could be separated. The acoustic emission released at the impact of the hammer onto the specimen is of lower frequency and its spectrum is strongly decreasing with increasing frequency. Plastic deformation also emits signals of lower frequency that are of quasi-continuous character. Both signal types can be discriminated by filtering. As a consequence typical burst signal were received afterwards that can be correlated with crack propagation. Their spectra exhibit considerable portions up to about 1.9 MHz. The development in time of the burst signals points to the kind of crack propagation resp. its sequence of appearance. However, definitive comparison between load and acoustic emission should become possible, only when the disadvantages of the common load measurement can be reduced, e.g. by determining the load directly at the specimen instead of the hammer tup

Impact of the economic recession on the European power sector's CO2 emissions

International Nuclear Information System (INIS)

Declercq, Bruno; Delarue, Erik; D'haeseleer, William

2011-01-01

This paper investigates the impact of the economic recession on CO 2 emissions in the European power sector, during the years 2008 and 2009. Three main determinants of the power sector's emissions are identified: the demand for electricity, the CO 2 price, and fuel prices. A counterfactual scenario has been set up for each of these, i.e., what these parameters would have been if not affected by the recession. A simulation model of the European power sector is then employed, comparing a historical reference simulation (taking the parameters as actually occurred) with the counterfactual scenarios. The lower electricity demand (due to the recession) is shown to have by far the largest impact, accounting for an emission reduction of about 175 Mton. The lower CO 2 price (due to the recession) resulted in an increase in emissions by about 30 Mton. The impact of fuel prices is more difficult to retrieve; an indicative reduction of about 17 Mton is obtained, mainly as a consequence of the low gas prices in 2009. The simulated combined impact of the parameters results in an emission reduction of about 150 Mton in the European power sector over the years 2008 and 2009 as a consequence of the recession. - Research highlights: → CO 2 emissions are simulated for the European power sector. → Emissions reduced drastically because of the economic recession in 2008 and 2009. → Lower electricity demand had highest impact and accounts for reduction of about 175 Mton. → Impact of different CO 2 and fuel prices on emissions is more limited.

Contamination des produits agricoles et de la nappe phréatique par ...

African Journals Online (AJOL)

Au Senegal, les enquetes menees dans la zone agricole des Niayes ont revele une mauvaise gestion des pesticides de la part des producteurs peu soucieux de leur impact sur lfenvironnement et la qualite des productions. Lfanalyse chromatographique apres extraction et purification a montre la presence de residus de ...

Impacts of Residential Biofuel Emissions on Air Quality and Climate

Science.gov (United States)

Huang, Y.; Unger, N.; Harper, K.; Storelvmo, T.

2016-12-01

The residential biofuel sector is defined as fuelwood, agricultural residues and dung used for household cooking and heating. Aerosol emissions from this human activity play an important role affecting local, regional and global air quality, climate and public health. However, there are only few studies available that evaluate the net impacts and large uncertainties persist. Here we use the Community Atmosphere Model version 5.3 (CAM v5.3) within the Community Earth System Model version 1.2.2, to quantify the impacts of cook-stove biofuel emissions on air quality and climate. The model incorporates a novel advanced treatment of black carbon (BC) effects on mixed-phase/ice clouds. We update the global anthropogenic emission inventory in CAM v5.3 to a state-of-the-art emission inventory from the Greenhouse Gas-Air Pollution Interactions and Synergies integrated assessment model. Global in-situ and aircraft campaign observations for BC and organic carbon are used to evaluate and validate the model performance. Sensitivity simulations are employed to assess the impacts of residential biofuel emissions on regional and global direct and indirect radiative forcings in the contemporary world. We focus the analyses on several key regions including India, China and Sub-Saharan Africa.

Global health impacts and costs due to mercury emissions.

Science.gov (United States)

Spadaro, Joseph V; Rabl, Ari

2008-06-01

Since much of the emission is in the form of metallic Hg whose atmospheric residence time is long enough to cause nearly uniform mixing in the hemisphere, much of the impact is global. This article presents a first estimate of global average neurotoxic impacts and costs by defining a comprehensive transfer factor for ingestion of methyl-Hg as ratio of global average dose rate and global emission rate. For the dose-response function (DRF) we use recent estimates of IQ decrement as function of Hg concentration in blood, as well as correlations between blood concentration and Hg ingestion. The cost of an IQ point is taken as $18,000 in the United States and applied in other countries in proportion to per capita GDP, adjusted for purchase power parity. The mean estimate of the global average of the marginal damage cost per emitted kg of Hg is about $1,500/kg, if one assumes a dose threshold of 6.7 mug/day of methyl-Hg per person, and $3,400/kg without threshold. The average global lifetime impact and cost per person at current emission levels are 0.02 IQ points lost and $78 with and 0.087 IQ points and $344 without threshold. These results are global averages; for any particular source and emission site the impacts can be quite different. An assessment of the overall uncertainties indicates that the damage cost could be a factor 4 smaller or larger than the median estimate (the uncertainty distribution is approximately log normal and the ratio median/mean is approximately 0.4).

Impact of biogenic emissions on ozone formation in the Mediterranean area - a BEMA modelling study

International Nuclear Information System (INIS)

Thunis, P.; Cuvelier, C.

2000-01-01

The aim of this modelling study is to understand and quantify the influence of biogenic volatile organic compound (BVOC) emissions on the formation of tropospheric ozone in the Burriana area (north of Valencia) on the east coast of Spain. The mesoscale modelling system used consists of the meteorology/transport module TVM and the chemical reaction mechanism RACM. The results of the model simulations are validated and compared with the data collected during the biogenic emissions in the mediterranean area (BEMA) field campaign that took place in June 1997. Anthropogenic and biogenic emission inventories have been constructed with an hourly resolution. Averaged (over the land area and over 24 h) emission fluxes for AVOC, anthropogenic NO x , BVOC and biogenic NO x are given by 16.0, 9.9, 6.2, and 0.7 kg km -2 day -1 , respectively. The impact of biogenic emissions is investigated on peak ozone values by performing simulations with and without biogenic emissions; while keeping anthropogenic emissions constant. The impact on ozone formation is also studied in combination with some anthropogenic emissions reduction strategies, i.e. when anthropogenic VOC emissions and/or NO x emissions are reduced. A factor separation technique is applied to isolate the impact due to biogenic emissions from the overall impact due to biogenic and anthropogenic emissions together. The results indicate that the maximum impact of biogenic emissions on ozone formation represents at the most 10 ppb, while maximum ozone values are of the order of 100 ppb. At different locations the maximum impact is reached at different times of the day depending on the arrival time of the sea breeze. It is also shown that this impact does not coincide in time with the maximum simulated ozone concentrations that are reached over the day. By performing different emission reduction scenarios, BVOC impacts are found to be sensitive mainly to NO x , and not to AVOC. Finally, it is shown that amongst the various

Inventory of primary particulates emissions; Inventaire des emissions de particules primaires

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-12-01

CITEPA carried out a national inventory on particulate emissions. This report presents the results of this study for a great number of sectors and it covers a larger number of sources than the previous CITEPA inventories on particles and some other inventories carried out by International organisms (TNO, IIASA). In particular, at the present time, fugitive dust emissions for some sources are rarely taken into account in inventories because of poor knowledge and they are still the subject of researches in order to validate the emission results. (author)

Les effets géographiques des éruptions volcaniques

Directory of Open Access Journals (Sweden)

Franck Lavigne

2010-12-01

Full Text Available Les méthodes de réflexion géographique permettent d’appréhender efficacement les jeux d’échelles et les temporalités multiples des effets induits par les éruptions volcaniques. L’objectif de cette synthèse est ainsi de comprendre les espaces volcaniques en tant qu’objets géographiques, en replaçant les impacts des éruptions au cœur d’une étude spatiale et temporelle. Les impacts de tels événements imposent des recompositions spatiales à l’échelle du volcan lui-même, et, dans le cas d’éruptions de plus grande magnitude, peuvent avoir des conséquences à l’échelle régionale voire mondiale. Les divers exemples abordés ici mettent l’accent sur les risques, la vulnérabilité et la résilience des populations vivant sur ces espaces marqués par les aléas volcaniques.The purpose of this paper aims to study the volcanic areas as geographical objects. Geographical analyses help to understand at different scales the levels of impacts induced by volcanic eruptions. Impacts of such events trigger spatial changes across the volcano itself, and can have consequences at regional or even global level in case of outbreaks of greater magnitude. The various examples discussed here focus on hazards, vulnerability and resilience of people living in those volcanic-hazard prone areas.

The impacts of population change on carbon emissions in China during 1978-2008

Energy Technology Data Exchange (ETDEWEB)

Zhu Qin, E-mail: zhuqin@fudan.edu.cn; Peng Xizhe, E-mail: xzpeng@fudan.edu.cn

2012-09-15

This study examines the impacts of population size, population structure, and consumption level on carbon emissions in China from 1978 to 2008. To this end, we expanded the stochastic impacts by regression on population, affluence, and technology model and used the ridge regression method, which overcomes the negative influences of multicollinearity among independent variables under acceptable bias. Results reveal that changes in consumption level and population structure were the major impact factors, not changes in population size. Consumption level and carbon emissions were highly correlated. In terms of population structure, urbanization, population age, and household size had distinct effects on carbon emissions. Urbanization increased carbon emissions, while the effect of age acted primarily through the expansion of the labor force and consequent overall economic growth. Shrinking household size increased residential consumption, resulting in higher carbon emissions. Households, rather than individuals, are a more reasonable explanation for the demographic impact on carbon emissions. Potential social policies for low carbon development are also discussed. - Highlights: Black-Right-Pointing-Pointer We examine the impacts of population change on carbon emissions in China. Black-Right-Pointing-Pointer We expand the STIRPAT model by containing population structure factors in the model. Black-Right-Pointing-Pointer The population structure includes age structure, urbanization level, and household size. Black-Right-Pointing-Pointer The ridge regression method is used to estimate the model with multicollinearity. Black-Right-Pointing-Pointer The population structure plays a more important role compared with the population size.

L’impact des facteurs économiques sur l’intention entrepreneuriale

Directory of Open Access Journals (Sweden)

Amari Farouk

2014-03-01

Nous avons cherché à apporter des éléments de réponse à la question de savoir comment ces facteurs peuvent-ils influencer l’intention de l’entrepreneur de créer son propre projet. Nous avons ciblé le milieu universitaire à travers une enquête auprès d’un échantillon d’étudiants de l’Institut Supérieur d’Administration des Affaires de Sfax (Tunisie.

Developing an indicator for the chronic health impact of traffic-related pollutant emissions

International Nuclear Information System (INIS)

Lépicier, Véronique; Chiron, Mireille; Joumard, Robert

2013-01-01

The goal of this study is to develop an emission based indicator for the health impact of the air pollution caused by traffic. This indicator must make it possible to compare different situations, for example different Urban Travel Plans, or technical innovations. Our work is based on a literature survey of methods for evaluating health impacts and, more particularly, those which relate to the atmospheric pollution caused by transport. We then define a health impact indicator based on the traffic emissions, named IISCEP for Chronic health impact indicator of pollutant emission. Here health is understood in a restricted meaning, excluding well-being. Only primary pollutants can be considered, as the inputs are emission data and an indicator must be simple. The indicator is calculated as the sum of each pollutant emission multiplied by a dispersion and exposition factor and a substance specific toxicity factor taking account of the severity. Last, two examples are shown using the IISCEP: comparison between petrol and diesel vehicles, and Nantes urban district in 2008 vs 2002. Even if it could still be improved, IISCEP is a straightforward indicator which can be used to gauge the chronic effects of inhaling primary pollutants. It can only be used in comparisons, between different scenarios or different technologies. The quality of the emissions data and the choice of the pollutants that are considered are the two essential factors that determine its validity and reliability. - Highlights: ► The goal of the study is to develop an emission based indicator for the health impact of the air pollution caused by traffic. ► It is based on a literature survey of methods for evaluating health impacts related to the atmospheric pollution. ► We define a composite indicator based on the traffic emissions and on local data as dispersion conditions and population. ► The indicator is a combination of pollutant emission, dispersion, exposition factor, and substance specific

Ion-impact secondary emission in negative corona with photoionization

Directory of Open Access Journals (Sweden)

B. X. Lu

2017-03-01

Full Text Available A corona discharge measurement system and simulation model are presented to investigate the effects of photoionization and ion-impact secondary emission process in negative corona discharge. The simulation results obtained is shown good agreement with experimental observations. Distribution of electron density along the symmetry axis at three critical moments is shown and the role of photoionization in negative corona discharge is clearly explained. Moreover, the current pulses are also presented under different secondary emission coefficients and the effect of the secondary emission coefficient is discussed.

Gestion des connaissances : le pilier oublié du développement ...

International Development Research Centre (IDRC) Digital Library (Canada)

Une stratégie complète de Gestion et de Partage des Connaissances peut améliorer considérablement l'efficacité, le bon fonctionnement et l'impact des politiques agricoles et des réformes agricoles proposées dans la région MOAN selon une étude ...

Analysis of regional difference on impact factors of China’s energy – Related CO2 emissions

International Nuclear Information System (INIS)

Li, Huanan; Mu, Hailin; Zhang, Ming; Gui, Shusen

2012-01-01

With the intensification of global warming, the issue of carbon emissions causes more and more attention in recent years. In this paper, China’s 30 provincial-level administrative units are divided into five emission regions according to the annual average value of provincial CO 2 emissions per capita during 1990 and 2010. The regional differences in impact factors on CO 2 emissions are discussed using STIRPAT (stochastic impacts by regression on population, affluence, and technology) model. The results indicate that although GDP (Gross domestic product) per capita, industrial structure, population, urbanization and technology level have different impacts on CO 2 emissions in different emission regions, they are almost always the main factors in all emission regions. In most emission regions, urbanization and GDP per capita has a bigger impact on CO 2 emissions than other factors. Improving technology level produces a small reduction in CO 2 emissions in most emission regions, but it is still a primary way for CO 2 reduction in China. It’s noteworthy that industrial structure isn’t the main factor and improving technology level increases CO 2 emissions in high emission region. Different measures should be adopted for CO 2 reductions according to local conditions in different regions. -- Highlights: ► Regional differences of the impact factors on China’s CO 2 emissions are analyzed. ► Five macro factors like GDP per capita are almost always main influence factors in all regions. ► The impacts of different factors are different. ► Improving technology has no significant reduction on CO 2 emission in most regions. ► Policy on CO 2 reduction should be adapted to local conditions.

Enhanced marine sulphur emissions offset global warming and impact rainfall.

Science.gov (United States)

Grandey, B S; Wang, C

2015-08-21

Artificial fertilisation of the ocean has been proposed as a possible geoengineering method for removing carbon dioxide from the atmosphere. The associated increase in marine primary productivity may lead to an increase in emissions of dimethyl sulphide (DMS), the primary source of sulphate aerosol over remote ocean regions, potentially causing direct and cloud-related indirect aerosol effects on climate. This pathway from ocean fertilisation to aerosol induced cooling of the climate may provide a basis for solar radiation management (SRM) geoengineering. In this study, we investigate the transient climate impacts of two emissions scenarios: an RCP4.5 (Representative Concentration Pathway 4.5) control; and an idealised scenario, based on RCP4.5, in which DMS emissions are substantially enhanced over ocean areas. We use mini-ensembles of a coupled atmosphere-ocean configuration of CESM1(CAM5) (Community Earth System Model version 1, with the Community Atmosphere Model version 5). We find that the cooling effect associated with enhanced DMS emissions beneficially offsets greenhouse gas induced warming across most of the world. However, the rainfall response may adversely affect water resources, potentially impacting human livelihoods. These results demonstrate that changes in marine phytoplankton activity may lead to a mixture of positive and negative impacts on the climate.

Efficacité des néonicotinoïdes et des pyréthrinoïdes utilisés contre le ...

African Journals Online (AJOL)

Efficacité des néonicotinoïdes et des pyréthrinoïdes utilisés contre le foreur des tiges du cacaoyer ( Eulophonotus myrmeleon Felder : Lepidoptera, Cossidae). Implications dans la stratégie de protection de la cacaoculture en Côte d'Ivoire.

Impacts of Energy Sector Emissions on PM2.5 Air Quality in Northern India

Science.gov (United States)

Karambelas, A. N.; Kiesewetter, G.; Heyes, C.; Holloway, T.

2015-12-01

India experiences high concentrations of fine particulate matter (PM2.5), and several Indian cities currently rank among the world's most polluted cities. With ongoing urbanization and a growing economy, emissions from different energy sectors remain major contributors to air pollution in India. Emission sectors impact ambient air quality differently due to spatial distribution (typical urban vs. typical rural sources) as well as source height characteristics (low-level vs. high stack sources). This study aims to assess the impacts of emissions from three distinct energy sectors—transportation, domestic, and electricity—on ambient PM2.5­­ in northern India using an advanced air quality analysis framework based on the U.S. EPA Community Multi-Scale Air Quality (CMAQ) model. Present air quality conditions are simulated using 2010 emissions from the Greenhouse Gas-Air Pollution Interaction and Synergies (GAINS) model. Modeled PM2.5 concentrations are compared with satellite observations of aerosol optical depth (AOD) from the Moderate Imaging Spectroradiometer (MODIS) for 2010. Energy sector emissions impacts on future (2030) PM2.5 are evaluated with three sensitivity simulations, assuming maximum feasible reduction technologies for either transportation, domestic, or electricity sectors. These simulations are compared with a business as usual 2030 simulation to assess relative sectoral impacts spatially and temporally. CMAQ is modeled at 12km by 12km and include biogenic emissions from the Community Land Model coupled with the Model of Emissions of Gases and Aerosols in Nature (CLM-MEGAN), biomass burning emissions from the Global Fires Emissions Database (GFED), and ERA-Interim meteorology generated with the Weather Research and Forecasting (WRF) model for 2010 to quantify the impact of modified anthropogenic emissions on ambient PM2.5 concentrations. Energy sector emissions analysis supports decision-making to improve future air quality and public health in

Impact des glucocorticoïdes plasmatiques sur la maturation et le fonctionnement de l'inhibition spinale GABAergique

OpenAIRE

Zell, Vivien

2013-01-01

Glucocorticoids (GC) such as corticosterone (CORT) in rats are synthetized following stress and HPA axis activation and are part of organisms response to homeostasis perturbations. Furthermore, GC can also alter pain perception. Les glucocorticoides (GC) sont des hormones stéroïdes synthétisées par les glandes surrénales suite à l’activation de l’axe hypothalamo-hypophysaire- surrénalien (ou axe HPA pour hypothalamic-pituitary-adrenal). Leur sécrétion pulsatile est sous le contrôle de l’ho...

Nigerian forest communities act to reduce carbon emissions | CRDI ...

International Development Research Centre (IDRC) Digital Library (Canada)

8 juin 2016 ... The collaborative project between One Sky Canadian Institute for Sustainable Living and the African Integral Development Network assessed the perceptions of local communities about carbon emissions offset ... La majorité des habitants de l'Inde vivent dans des régions soumises à un stress hydrique.

Caractéristiques des substrats et interactions dans les filières de co-digestion : cas particulier des co-substrats d’origine agro-industrielle

Directory of Open Access Journals (Sweden)

GIRAULT, Romain

2013-10-01

Full Text Available Pour assurer l’équilibre économique des unités de méthanisation, l’ajout de co-substrats est en général nécessaire. Pour les choisir, deux questions se posent aux porteurs de projets : quelles sont les caractéristiques des co-substrats disponibles et quel est l’impact des mélanges sur le fonctionnement du digesteur. Le présent article se propose de répondre à ces questions sur la base des résultats du projet Biodecol2.

Mesures experimentales de l'impact des revetements hydrophobeset superhydrophobes sur la trainee et la portance d'un profil aerodynamique propre et glace

Science.gov (United States)

Villeneuve, Eric

Ce projet, realise a la demande du Laboratoire International des Materiaux Antigivre, a pour but de mesurer et definir experimentalement l'impact de revetements hydrophobes sur les coefficients de trainee et de portance d'un profil NACA 0012. Pour ce faire, la balance aerodynamique du LIMA devait tout d'abord etre amelioree afin d'offrir une sensibilite suffisante pour realiser le projet. Plusieurs ameliorations ont ete faites, comme le changement des cellules de charge, la diminution du nombre de cellules de charge, le changement du cadre de la balance, etc. Une fois ces ameliorations terminees, la reproductibilite, l'exactitude et la sensibilite ont ete valides afin de s'assurer de la fiabilite des resultats offerts par la balance. Pour les angles d'attaque etudies avec les revetements, soient -6° et 0°, la balance a une reproductibilite de +/-2,06% a 360 000 de nombre de Reynolds. Pour valider la sensibilite, des essais a -6° et 0° d'angle d'attaque et des nombres de Reynolds de 360 000 et 500 000 ont ete faits avec des papiers sables. Les resultats de ces essais ont permis de, tracer des courbes de tendances du coefficient de trainee du NACA 0012 en fonction de la rugosite de surface et d'etablir la valeur de la sensibilite de la balance a +/-8 mu m. Cinq revetements populaires ont ete choisis pour l'experimentation, soient le Wearlon, le Staclean, le Hirec, le Phasebreak ainsi que le Nusil. Les revetements sont soumis aux memes conditions experimentales que les papiers sables, et une rugosite equivalente est trouvee par extrapolation des resultats. Cependant, les rugosites equivalentes de surfaces different entre -6° et 0°. Les essais avec le Staclean et le Hirec donnent des coefficients de trainee equivalent a ceux avec l'aluminium, alors que le Wearlon, le Nusil et le Phasebreak donnent une augmentation du coefficient de trainee de 13%, 17% et 25% respectivement par rapport a l'aluminium. Pour les coefficients de portance, la balance ne detecte pas l

Évaluation de la contamination parasitologique des eaux usées ...

African Journals Online (AJOL)

SARAH

30 sept. 2013 ... l'équilibre écologique du milieu naturel, surtout par la pollution des eaux de surface et des nappes phréatiques et un risque sanitaire par contamination microbiologique ou parasitaire (Diop, 1994 ;. Khallaayoune, 2005 ; Sawadogo et al., 2005). Pour atténuer ces impacts négatifs des eaux usées brutes sur ...

Emissions impacts of wind and energy storage in a market environment.

Science.gov (United States)

Sioshansi, Ramteen

2011-12-15

This study examines the emissions impacts of adding wind and energy storage to a market-based electric power system. Using Texas as a case study, we demonstrate that market power can greatly effect the emissions benefits of wind, due to most of the coal-fired generation being owned by the two dominant firms. Wind tends to have less emissions benefits when generators exercise market power, since coal-fired generation is withheld from the market and wind displaces natural gas-fired generators. We also show that storage can have greater negative emissions impacts in the presence of wind than if only storage is added to the system. This is due to wind increasing on- and off-peak electricity price differences, which increases the amount that storage and coal-fired generation are used. We demonstrate that this effect is exacerbated by market power.

Degré d'impact des aménagements hydrauliques sur le ...

African Journals Online (AJOL)

La variation se fait en fonction des conditions écologiques et des mauvaises conditions de gestion de la terre par l'homme. C'est pourquoi la lutte ... De nombreux chercheurs se sont penchés pour traiter ce problème ; que ce soit dans l'aspect de quantification que dans celui de la lutte anti-érosive. Nous avons tenté ...

Santé des adolescents et des jeunes au Burkina Faso : état des ...

African Journals Online (AJOL)

Il s'est agi d'une étude évaluative ayant utilisé une revue documentaire associée à une interview des acteurs clés et un atelier de validation et d'identification des interventions pertinentes pour un plan stratégique national. La situation de la santé des adolescents et des jeunes est caractérisée par des grossesses précoces ...

Comparison of methodologies estimating emissions of aircraft pollutants, environmental impact assessment around airports

International Nuclear Information System (INIS)

Kurniawan, Jermanto S.; Khardi, S.

2011-01-01

Air transportation growth has increased continuously over the years. The rise in air transport activity has been accompanied by an increase in the amount of energy used to provide air transportation services. It is also assumed to increase environmental impacts, in particular pollutant emissions. Traditionally, the environmental impacts of atmospheric emissions from aircraft have been addressed in two separate ways; aircraft pollutant emissions occurring during the landing and take-off (LTO) phase (local pollutant emissions) which is the focus of this study, and the non-LTO phase (global/regional pollutant emissions). Aircraft pollutant emissions are an important source of pollution and directly or indirectly harmfully affect human health, ecosystems and cultural heritage. There are many methods to asses pollutant emissions used by various countries. However, using different and separate methodology will cause a variation in results, some lack of information and the use of certain methods will require justification and reliability that must be demonstrated and proven. In relation to this issue, this paper presents identification, comparison and reviews of some of the methodologies of aircraft pollutant assessment from the past, present and future expectations of some studies and projects focusing on emissions factors, fuel consumption, and uncertainty. This paper also provides reliable information on the impacts of aircraft pollutant emissions in short term and long term predictions.

Impacts on CO2 Emission Allowance Prices in China: A Quantile Regression Analysis of the Shanghai Emission Trading Scheme

Directory of Open Access Journals (Sweden)

Jie Zhang

2016-11-01

Full Text Available A pilot regional carbon emission trading scheme (ETS has been implemented in China for more than two years. An investigation into the impacts of different factors on carbon dioxide (CO2 emission allowance prices provides guidance for price-making in 2017 when the nation-wide ETS of China will be established. This paper adopts a quantile regression approach to estimate the impacts of different factors in Shanghai emission trading scheme (SH-ETS, namely, economic growth, energy prices and temperature. The empirical analysis shows that: (i the economic growth in Shanghai leads to a drop in the carbon allowance prices; (ii the oil price has a slightly positive effect on the allowance prices regardless of the ordinary least squares (OLS or quantile regression method; (iii a long-run negative relationship exists between the coal price and the Shanghai emission allowances (SHEA prices, but a positive interaction under different quantiles, especially the 25%–50% quantiles; (iv temperature has a significantly positive effect at the 20%–30% quantiles and a conspicuous negative impact at the right tail of the allowances prices.

Prises de participation des grandes compagnies aériennes dans de petites compagnies en Europe: impacts sur la géographie des réseaux

Directory of Open Access Journals (Sweden)

Frédéric Dobruszkes

2009-03-01

Full Text Available La libéralisation du transport aérien européen a accru la tendance des grandes compagnies à prendre des parts dans des compagnies de taille plus modeste tout en diversifiant les motivations. Dans ce contexte, les réseaux aériens des secondes évoluent en fonction des intérêts des premières et sous la contrainte de la rentabilité financière. Les conséquences sur la géographie des réseaux aériens sont variables: tandis que les grandes compagnies concentrent leur offre sur un nombre réduit de hubs, les lignes plus secondaires ou de niche tendent à demeurer l’objet de filiales spécifiques, ou sont laissées à d’autres compagnies (en particulier de type low-cost ou sont supprimées au profit d’une concentration de l’offre ailleurs.

Afrique Science: Revue Internationale des Sciences et Technologie ...

African Journals Online (AJOL)

Degré d'impact des aménagements hydrauliques sur le ruissellement et le transport solide dans une région semi aride : cas des micro-bassins dans le haut Isser, Algérie · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. A Keddar, B Touaïbia, M Arabi ...

Global climate impacts of country-level primary carbonaceous aerosol from solid-fuel cookstove emissions

International Nuclear Information System (INIS)

Lacey, Forrest; Henze, Daven

2015-01-01

Cookstove use is globally one of the largest unregulated anthropogenic sources of primary carbonaceous aerosol. While reducing cookstove emissions through national-scale mitigation efforts has clear benefits for improving indoor and ambient air quality, and significant climate benefits from reduced green-house gas emissions, climate impacts associated with reductions to co-emitted black (BC) and organic carbonaceous aerosol are not well characterized. Here we attribute direct, indirect, semi-direct, and snow/ice albedo radiative forcing (RF) and associated global surface temperature changes to national-scale carbonaceous aerosol cookstove emissions. These results are made possible through the use of adjoint sensitivity modeling to relate direct RF and BC deposition to emissions. Semi- and indirect effects are included via global scaling factors, and bounds on these estimates are drawn from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. Absolute regional temperature potentials are used to estimate global surface temperature changes. Bounds are placed on these estimates, drawing from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. We estimate a range of 0.16 K warming to 0.28 K cooling with a central estimate of 0.06 K cooling from the removal of cookstove aerosol emissions. At the national emissions scale, countries’ impacts on global climate range from net warming (e.g., Mexico and Brazil) to net cooling, although the range of estimated impacts for all countries span zero given uncertainties in RF estimates and fuel characterization. We identify similarities and differences in the sets of countries with the highest emissions and largest cookstove temperature impacts (China, India, Nigeria, Pakistan, Bangladesh and Nepal), those with the largest temperature impact per carbon emitted (Kazakhstan, Estonia, and Mongolia), and those that would provide the

Global climate impacts of country-level primary carbonaceous aerosol from solid-fuel cookstove emissions

Science.gov (United States)

Lacey, Forrest; Henze, Daven

2015-11-01

Cookstove use is globally one of the largest unregulated anthropogenic sources of primary carbonaceous aerosol. While reducing cookstove emissions through national-scale mitigation efforts has clear benefits for improving indoor and ambient air quality, and significant climate benefits from reduced green-house gas emissions, climate impacts associated with reductions to co-emitted black (BC) and organic carbonaceous aerosol are not well characterized. Here we attribute direct, indirect, semi-direct, and snow/ice albedo radiative forcing (RF) and associated global surface temperature changes to national-scale carbonaceous aerosol cookstove emissions. These results are made possible through the use of adjoint sensitivity modeling to relate direct RF and BC deposition to emissions. Semi- and indirect effects are included via global scaling factors, and bounds on these estimates are drawn from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. Absolute regional temperature potentials are used to estimate global surface temperature changes. Bounds are placed on these estimates, drawing from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. We estimate a range of 0.16 K warming to 0.28 K cooling with a central estimate of 0.06 K cooling from the removal of cookstove aerosol emissions. At the national emissions scale, countries’ impacts on global climate range from net warming (e.g., Mexico and Brazil) to net cooling, although the range of estimated impacts for all countries span zero given uncertainties in RF estimates and fuel characterization. We identify similarities and differences in the sets of countries with the highest emissions and largest cookstove temperature impacts (China, India, Nigeria, Pakistan, Bangladesh and Nepal), those with the largest temperature impact per carbon emitted (Kazakhstan, Estonia, and Mongolia), and those that would provide the

Strategies endogenes d'adaptation des communautes rurales de la ...

African Journals Online (AJOL)

Cette étude est réalisée pour apprécier les impacts liés à la construction du barrage d'Akossombo sur les activités communautés rurales de la basse vallée de la Volta au Ghana. Les enquêtes menées auprès des ménages, des autorités administratives, des diverses structures et dans les champs ont permis de collecter les ...

Impact de la qualité de l'audit externe sur la liquidité des titres des entreprises tunisiennes cotées

OpenAIRE

Faten Hakim Ghorbel

2008-01-01

Cette recherche a pour objectif d'étudier l'impact de la qualité d'audit externe sur la liquidité. Nous appréhendons la qualité d'audit dans le cadre de notre étude par "la qualité de l'auditeur", et notamment de son indépendance et de ses compétences. Après avoir contrôlé l'effet d'autres variables censées, d'après la théorie, influencer la liquidité, les tests effectués ont permis de dégager une relation positive entre l'appartenance des auditeurs à un réseau international (Big 4), la spéci...

La fabrique des sciences des institutions aux pratiques

CERN Document Server

Benninghoff, Martin; Crettaz von Roten, Fabienne; Merz, Martina

2006-01-01

Aujourd'hui, les façons de produire, d'organiser, d'évaluer et d'utiliser les savoirs sont en profond débat. De plus en plus, l'Etat, la société civile et l'économie tentent d'influencer les activités des universités et des laboratoires de recherche. Ces développements mettent à l'épreuve tout à la fois les fondements des systèmes d'enseignement supérieur et de recherche, l'autonomie des institutions scientifiques, la définition des frontières des savoirs et l'acceptation des sciences. Dans des contextes suisses et européens, cet ouvrage s'intéresse aux manières dont les sciences et les technologies sont fabriquées, en analysant leurs institutions et les pratiques. A partir d'une approche relationnelle, les sciences et les technologies sont conçues comme des phénomènes profondément sociaux, culturels et politiques. Une telle démarche déstabilise les visions parfois idéalisées et stéréotypées de la construction des savoirs. Des études de cas détaillées décrivent des phénomè...

L'impact de Quizlet sur la dynamique motivationnelle des élèves lors de l'apprentissage du vocabulaire allemand

OpenAIRE

André, Joanne; Berrio, Lucas; Pellet, Jean-Philippe

2017-01-01

Pour ce travail, nous nous sommes intéressés à l'effet que pouvait avoir les TIC sur la motivation des élèves. Nous nous sommes penchés sur la plate-forme web Quizlet qui propose différents outils pour réviser un contenu préalablement défini par l'enseignant. Ainsi, nous avons dirigé notre recherche sur l'impact de Quizlet sur la dynamique motivationnelle des élèves dans le cadre de l'apprentissage du vocabulaire allemand. Nous comparons cette méthode d'apprentissage avec les méthodes dites t...

Assessing concentrations and health impacts of air quality management strategies: Framework for Rapid Emissions Scenario and Health impact ESTimation (FRESH-EST).

Science.gov (United States)

Milando, Chad W; Martenies, Sheena E; Batterman, Stuart A

2016-09-01

In air quality management, reducing emissions from pollutant sources often forms the primary response to attaining air quality standards and guidelines. Despite the broad success of air quality management in the US, challenges remain. As examples: allocating emissions reductions among multiple sources is complex and can require many rounds of negotiation; health impacts associated with emissions, the ultimate driver for the standards, are not explicitly assessed; and long dispersion model run-times, which result from the increasing size and complexity of model inputs, limit the number of scenarios that can be evaluated, thus increasing the likelihood of missing an optimal strategy. A new modeling framework, called the "Framework for Rapid Emissions Scenario and Health impact ESTimation" (FRESH-EST), is presented to respond to these challenges. FRESH-EST estimates concentrations and health impacts of alternative emissions scenarios at the urban scale, providing efficient computations from emissions to health impacts at the Census block or other desired spatial scale. In addition, FRESH-EST can optimize emission reductions to meet specified environmental and health constraints, and a convenient user interface and graphical displays are provided to facilitate scenario evaluation. The new framework is demonstrated in an SO2 non-attainment area in southeast Michigan with two optimization strategies: the first minimizes emission reductions needed to achieve a target concentration; the second minimizes concentrations while holding constant the cumulative emissions across local sources (e.g., an emissions floor). The optimized strategies match outcomes in the proposed SO2 State Implementation Plan without the proposed stack parameter modifications or shutdowns. In addition, the lower health impacts estimated for these strategies suggest that FRESH-EST could be used to identify potentially more desirable pollution control alternatives in air quality management planning

The impact of CO2 emissions on economic growth: evidence from selected higher CO2 emissions economies.

Science.gov (United States)

Azam, Muhammad; Khan, Abdul Qayyum; Bin Abdullah, Hussin; Qureshi, Muhammad Ejaz

2016-04-01

The main purpose of this work is to analyze the impact of environmental degradation proxied by CO2 emissions per capita along with some other explanatory variables namely energy use, trade, and human capital on economic growth in selected higher CO2 emissions economies namely China, the USA, India, and Japan. For empirical analysis, annual data over the period spanning between 1971 and 2013 are used. After using relevant and suitable tests for checking data properties, the panel fully modified ordinary least squares (FMOLS) method is employed as an analytical technique for parameter estimation. The panel group FMOLS results reveal that almost all variables are statistically significant, whereby test rejects the null hypotheses of non cointegration, demonstrating that all variables play an important role in affecting the economic growth role across countries. Where two regressors namely CO2 emissions and energy use show significantly negative impacts on economic growth, for trade and human capital, they tend to show the significantly positive impact on economic growth. However, for the individual analysis across countries, the panel estimate suggests that CO2 emissions have a significant positive relationship with economic growth for China, Japan, and the USA, while it is found significantly negative in case of India. The empirical findings of the study suggest that appropriate and prudent policies are required in order to control pollution emerging from areas other than liquefied fuel consumption. The ultimate impact of shrinking pollution will help in supporting sustainable economic growth and maturation as well as largely improve society welfare.

Pratiques agricoles et perceptions paysannes des impacts ...

African Journals Online (AJOL)

La dégradation des écosystèmes et d'une manière générale de l'environnement au Burkina Faso est liée aux ... L'étude a révélé que 8 types de rotations culturales sont pratiquées dans la zone. ..... OBEPAB (Organisation Béninoise pour la.

The impact of renewables and energy efficiency on greenhouse gas emissions

International Nuclear Information System (INIS)

2007-01-01

This report analyses the impact of renewables, CO2 pricing and energy efficiency improvements on CO2 emissions from stationary energy use in the Nordic countries except Iceland. Electricity and heat production (and use) account for the largest emissions from the Nordic economies. The analysis shows that CO2 emissions from 1990 to 2005 could have been as much as 3050% higher without the penetration of renewables in the energy system and the improvement in the energy intensity of GDP. Looking ahead, it is clear that both the EU ETS and renewables policies may have a significant impact on CO2 emissions. For moderate CO2 prices, the overlap between the two types of measures is not found to be substantial, although both yield significant CO2 emission reductions applied separately. This is because the measures to some extent apply to different sectors and uses. The effectiveness of energy efficiency improvements is also found to have a significant effect on emissions. Measures leading to a reduction in electricity consumption are found to be more effective than measures leading to a reduction in heat consumption. (au)

Utilisation des sous-produits agroalimentaires dans l’alimentation des poissons d’élevage en Côte d’Ivoire

Directory of Open Access Journals (Sweden)

Kimou Nestor B.

2016-03-01

Full Text Available Cette étude évalue l’impact de l’utilisation des sous-produits agroalimentaires dans l’alimentation des poissons d’élevage en Côte d’Ivoire. Une enquête a été réalisée en 2013 dans quinze principales zones piscicoles sur les caractéristiques technico-économiques des fermes, le profil socio-économique des promoteurs et les pratiques aquacoles, particulièrement l’alimentation des poissons. Les résultats révèlent que 71 % des pisciculteurs enquêtés utilisent des sous-produits agricoles durant au moins un stade de production. Parmi eux, 53 % utilisent exclusivement des sous-produits. Le son de riz (52 % et le mélange de sons de riz et de maïs (28 % sont les plus utilisés. Les prix moyens de ces sous-produits varient entre 20 et 105 FCFA/kg. Oreochromis niloticus et Heterotis niloticus sont les principales espèces élevées en polyculture sur les fermes. Les sous-produits sont utilisés en système semi-intensif, extensif et en rizipisciculture, en majorité en zone rurale. Les pisciculteurs sont pour la plupart des agriculteurs, âgés de plus de 40 ans. Les taux d’utilisation des sous-produits sont plus élevés dans les régions de l’Ouest, du Centre-Ouest et du Sud-Ouest de la Côte d’Ivoire, par rapport à celles du Sud et de l’Est. Les rendements des fermes sont relativement faibles (544 à 2445 kg/ha/an, avec des gains moyens quotidiens de 0,87 et 9,97 g/j pour le tilapia et l’heterotis respectivement. L’analyse des stratégies des acteurs suggère la nécessité de définir des mécanismes d’accompagnement et de financement de la pisciculture, afin que ces acteurs puissent améliorer les formulations alimentaires à partir des matières premières locales et accessibles.

DES/CCHP: The best utilization mode of natural gas for China’s low carbon economy

International Nuclear Information System (INIS)

Li, Yajun; Xia, Yan

2013-01-01

In this paper, through the analysis of the great challenges faced by China’s energy industry in the development of low carbon economy, it is advisable that China increase the proportion of natural gas (NG) in primary energy as the main strategy of energy conservation and CO 2 reduction in the advancement of industrialization and urbanization. In the near future, NG will become one of the major energy suppliers for new towns and industrial parks, and work for electric peak shaving when used in distributed energy system/combined cold, heat and power (DES/CCHP). However, as an efficient approach to improve the energy utilization efficiency, DES/CCHP cannot only increase the current energy efficiency from 33% to 50.3% (the world’s average), but also reduce the cost of terminal supplies of power, cold, steam and hot water. It will become one of the most important means to control CO 2 emissions in the next 20 years, and is essential to China’s low carbon industrialization and urbanization. - Highlights: ► China’s high economic growth has lead to a huge amount of carbon emissions. ► Climate change calls for a low carbon economy in China. ► The pressure of carbon emission reduction requires China reduce the excessive dependency on coal and oil. ► Natural gas used in distributed energy system/combined cold, heat and power (NG DES/CCHP) is low in carbon emission. ► NG DES/CCHP is the optimal energy supplier for a low carbon economy in China.

The impacts of population change on carbon emissions in China during 1978–2008

International Nuclear Information System (INIS)

Zhu Qin; Peng Xizhe

2012-01-01

This study examines the impacts of population size, population structure, and consumption level on carbon emissions in China from 1978 to 2008. To this end, we expanded the stochastic impacts by regression on population, affluence, and technology model and used the ridge regression method, which overcomes the negative influences of multicollinearity among independent variables under acceptable bias. Results reveal that changes in consumption level and population structure were the major impact factors, not changes in population size. Consumption level and carbon emissions were highly correlated. In terms of population structure, urbanization, population age, and household size had distinct effects on carbon emissions. Urbanization increased carbon emissions, while the effect of age acted primarily through the expansion of the labor force and consequent overall economic growth. Shrinking household size increased residential consumption, resulting in higher carbon emissions. Households, rather than individuals, are a more reasonable explanation for the demographic impact on carbon emissions. Potential social policies for low carbon development are also discussed. - Highlights: ► We examine the impacts of population change on carbon emissions in China. ► We expand the STIRPAT model by containing population structure factors in the model. ► The population structure includes age structure, urbanization level, and household size. ► The ridge regression method is used to estimate the model with multicollinearity. ► The population structure plays a more important role compared with the population size.

L'impact des développements scientifiques sur la résolution des problèmes techniques posés par la nouvelle conjoncture dans l'exploration et la production du pétrole Impact of Scientific Developments on the Solving of Technical Problems Raised by the New Economic Situation in Oil Exploration and Production

Directory of Open Access Journals (Sweden)

Tissot B.

2006-11-01

Full Text Available Dans les circonstances difficiles que traverse l'exploration et la production du pétrole, le savoir-faire technologique, associé à la maîtrise des coûts, seront pour l'industrie pétrolière et parapétrolière des atouts essentiels. On envisage ici l'impact prévisible des développements scientifiques sur la résolution des problèmes techniques dans l'exploration et la production. Les principales disciplines scientifiques concernées (géologie, géophysique, géochimie, mécanique des roches et des sols, mécanique des fluides, physicochimie des interfaces ainsi que trois techniques de base (modélisation, systèmes experts, matériaux nouveaux sont examinées dans ce sens. En particulier,la modélisation numérique voit son importance croître de manière spectaculaire : elle couvre désormais des domaines nouveaux, comme les Sciences de la Terre, et continue à s'enrichir de développements importants, même dans les secteurs où on l'utilise depuis 20 ans comme la production. Ces évolutions s'accompagneront nécessairement d'ajustements dans la formation des hommes et le fonctionnement des organisations; en particulier un espace nouveau pourrait se dégager pour de petites entreprises de conseil et de service plus riches en matière grise qu'en investissements lourds. In the difficult circumstances now confronting oil exploration and production, technical know-how combined with cost control will be essential assets for the petroleum and petroleum equipment and service industries. This article considers the foreseeable impact of scientific developments on the solving of technical problems in exploration and production. The principal scientific disciplines involved (geology, geophysics, geochemistry, rock and soil mechanics, fluid mechanics, interface physicochemistry as well as three basic techniques (modeling, expert systems, new materials are examined within this context. In particular, numerical modeling is increasing in

Acoustic emission measurements during impacts tests for determining ductile fracture data

International Nuclear Information System (INIS)

Richter, H.

2000-09-01

The document reports work for further development of methods and tests to obtain better information on the crack initiation toughness (J id ) under impact loading conditions, by acoustic emission measurements. The applicability of the acoustic emission tests for the given purpose was proven by instrumented Charpy tests using modified ISO-V specimens. The physical crack initiation toughness served as the reference value for reliable evaluation of the characteristic data obtained. This reference value is derived from the crack resistance curve determined by the multi-specimen cleavage fracture method combined with data from measurements of the stretching zone width. Verification of the acoustic emission-defined initiation value included a variety of tests, as e.g. additional dynamic single-specimen methods (L-COD, magnetic emission), and supplementary tests (D3PB, pendulum impact testing machine). The test materials are various steels with different strength/toughness properties. (orig./CB) [de

Impacts of Interannual Variability in Biogenic VOC Emissions near Transitional Ozone Production Regimes

Science.gov (United States)

Geddes, J.

2017-12-01

Due to successful NOx emission controls, summertime ozone production chemistry in urban areas across North America is transitioning from VOC-limited to increasingly NOx-limited. In some regions where ozone production sensitivity is in transition, interannual variability in surrounding biogenic VOC emissions could drive fluctuations in the prevailing chemical regime and modify the impact of anthropogenic emission changes. I use satellite observations of HCHO and NO2 column density, along with a long-term simulation of atmospheric chemistry, to investigate the impact of interannual variability in biogenic isoprene sources near large metro areas. Peak emissions of isoprene in the model can vary by up to 20-60% in any given year compared to the long term mean, and this variability drives the majority of the variability in simulated local HCHO:NO2 ratios (a common proxy for ozone production sensitivity). The satellite observations confirm increasingly NOx-limited chemical regimes with large interannual variability. In several instances, the model and satellite observations suggest that variability in biogenic isoprene emissions could shift summertime ozone production from generally VOC- to generally NOx- sensitive (or vice versa). This would have implications for predicting the air quality impacts of anthropogenic emission changes in any given year, and suggests that drivers of biogenic emissions need to be well understood.

Impact Of Real-World Driving Characteristics On Vehicular Emissions

OpenAIRE

Nesamani, K S; Subramanian, K. P.

2005-01-01

With increase in traffic volume and change in travel related characteristics, vehicular emissions and energy consumption have increased significantly since two decades in India. Current models are not capable of estimating vehicular emissions accurately due to inadequate representation of real-world driving. The focus of this paper is to understand the level of Indian Driving cycle (IDC) in representing the real-world driving and to assess the impact of real-world driving on vehicular emissio...

Xe CONGRES INTERNATIONAL SUR LE COLZA Développement et impacts des OGM

Directory of Open Access Journals (Sweden)

Chevre Anne-Marie

2000-01-01

Full Text Available Le dernier congrès du Groupe consultatif international de recherches sur le colza s’est déroulé à Canberra (Australie du 26 septembre au 1er octobre 1999. Pour sa dixième édition, cette manifestation, quadriennale, a réuni plus de 600 participants originaires de 28 pays. La délégation australienne mise en part (35 % des participants, le Canada (15 % et l’Allemagne (14 % étaient les pays producteurs les mieux representés suivis de la Grande-Bretagne (6 %, de la France (6 % et de la Chine (5 %. Résumé en chiffre, le contenu scientifique de ces journées a été apporté par 550 présentations de résultats sous forme d’exposés (166 et de posters (384. Parmi les différents thèmes développés, le thème « amélioration des plantes et biotechnologies » a occupé en nombre d’interventions, à peu près la moitié du congrès (44 %. Les notes suivantes reviennent sur les aspects significatifs de ces présentations. Elles seront suivies dans une prochaine livraison des comptes rendus des thèmes « agronomie », « protection des cultures » et « nutrition ». (Les références au sein des articles renvoient aux textes du CDrom du colloque disponible auprès du Dr Rodney Mailer  : mailerr@agric.nsw.gov.au

Etude du processus de changement vecu par des familles ayant decide d'adopter volontairement des comportements d'attenuation des changements climatiques

Science.gov (United States)

Leger, Michel T.

Les activites humaines energivores telles l'utilisation intensive de l'automobile, la surconsommation de biens et l'usage excessif d'electricite contribuent aux changements climatiques et autres problemes environnementaux. Bien que plusieurs recherches rapportent que l'etre humain est de plus en plus conscient de ses impacts sur le climat de la planete, ces memes recherches indiquent qu'en general, les gens continuent a se comporter de facon non ecologique. Que ce soit a l'ecole ou dans la communaute, plusieurs chercheurs en education relative a l'environnement estiment qu'une personne bien intentionnee est capable d'adopter des comportements plus respectueux de l'environnement. Le but de cette these etait de comprendre le processus d'integration de comportements d'attenuation des changements climatiques dans des familles. A cette fin, nous nous sommes fixe deux objectifs : 1) decrire les competences et les procedes qui favorisent l'adoption de comportements d'attenuation des changements climatiques dans des familles et 2) decrire les facteurs et les dynamiques familiales qui facilitent et limitent l'adoption de comportements d'attenuation des changements climatiques dans des familles. Des familles ont ete invitees a essayer des comportements personnels et collectifs d'attenuation des changements climatiques de sorte a integrer des modes de vie plus ecologiques. Sur une periode de huit mois, nous avons suivi leur experience de changement afin de mieux comprendre comment se produit le processus de changement dans des familles qui decident volontairement d'adopter des comportements d'attenuation des changements climatiques. Apres leur avoir fourni quelques connaissances de base sur les changements climatiques, nous avons observe le vecu de changement des familles durant huit mois d'essais a l'aide de journaux reflexifs, d'entretiens d'explicitation et du journal du chercheur. La these comporte trois articles scientifiques. Dans le premier article, nous presentons une

Neutron emission from impacted solid LiD samples

International Nuclear Information System (INIS)

Kaushik, T.C.; Shyam, A.; Kulkarni, L.V.; Srinivasan, M.

1993-01-01

Nylon projectiles with 0.1 g to 0.3 g mass, accelerated to velocities of 0.2-1 km/s using a 60 cm long electromagnetic accelerator (railgun), have been impacted upon solid lithium deuteride (LiD) samples of 3 proportional counters. The output from the BF 3 set-up is monitored in several ways to characterize the possible neutron emission from the target. This includes a simple technique of counting the single channel analyser (SCA) output through a dead-time unit to identify bursts of < 100 μs duration. Counting is started after a delay of ∼ 1 ms to avoid the initial interference from the capacitor bank discharge. The signal is also recorded in a storage oscilloscope from the start of projectile acceleration along with a time marker just before the impact. From a number of shots taken with and without the samples, a significant evidence of neutron emission from the LiD samples appears to emerge. The experiments suggest that approximately 100 neutrons might be generated during every such impact in a duration of < 4 ms. (author). 7 refs., 3 figs

Tombes et cimetières éthiopiens : des rois, des saints, des anonymes1

OpenAIRE

Derat, Marie-Laure

2009-01-01

L’histoire des tombes et cimetières éthiopiens, dans la longue durée, en est encore à ses balbutiements. Si les tombes des saints et des rois nous sont un peu mieux connus grâce à des textes témoignant à la fois des enjeux entourant les sépultures de ces personnages hors du commun et des soins apportés à leur inhumation, en revanche, les cimetières ordinaires échappent encore largement à l’enquête, en grande partie parce que le commun des mortels est inhumé dans l’anonymat et dans un grand dé...

Impact des matériaux biosourcés sur le climat intérieur : Un outil de calcul flexible à l'échelle de la pièce

OpenAIRE

Dubois, Samuel; Lebeau, Frédéric

2014-01-01

L'impact de l'utilisation de matériaux d'origine végétale sur le climat intérieur, et donc sur le confort des occupants ainsi que la performance énergétique du bâtiment, n'est établi que partiellement. Ces produits présentent des propriétés hygroscopiques et capillaires causant des phénomènes spécifiques liés aux changements de phase dynamiques au sein de la matrice poreuse. Les modèles mathématiques utilisés pour étudier leur comportement hygrothermique de manière détaillée sont souvent des ...

Évaluation des pratiques agricoles des légumes feuilles : le cas des ...

African Journals Online (AJOL)

Face à ce constat, le défi de la recherche serait la détermination du niveau actuel de contamination des légumes feuilles et des eaux du barrage et celui de l'État serait l'initiation de programmes de sensibilisation des producteurs par rapport à une gestion plus rigoureuse des pesticides. Mots-clés : pratiques paysannes, ...

La convergence des rôles respectifs des relationnistes et des journalistes influence-t-elle la perception qu'ils ont les uns des autres?

DEFF Research Database (Denmark)

Valentini, Chiara

2017-01-01

la convergence des rôles respectifs des praticiens des relations publiques et des journalistes a un effet favorable sur la perception qu’ils ont les uns des autres. L’effet est plus marqué chez les praticiens des relations publiques, car leur vision de la profession en journalisme correspond à celle...

Comparing climate and cost impacts of reference levels for reducing emissions from deforestation

Energy Technology Data Exchange (ETDEWEB)

Busch, Jonah [Center for Applied Biodiversity Science, Conservation International, 2011 Crystal Drive, Suite 500, Arlington, VA (United States); Strassburg, Bernardo [Center for Social and Economic Research on the Global Environment, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Cattaneo, Andrea [Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540-1644 (United States); Lubowski, Ruben [Environmental Defense Fund, 1875 Connecticut Avenue NW, Washington, DC (United States); Bruner, Aaron; Rice, Richard; Boltz, Frederick [Conservation International, 2011 Crystal Drive, Suite 500, Arlington, VA (United States); Creed, Anna; Ashton, Ralph, E-mail: jbusch@conservation.or [Terrestrial Carbon Group, 900 17th Street NW, Suite 700, Washington, DC (United States)

2009-10-15

The climate benefit and economic cost of an international mechanism for reducing emissions from deforestation and degradation (REDD) will depend on the design of reference levels for crediting emission reductions. We compare the impacts of six proposed reference level designs on emission reduction levels and on cost per emission reduction using a stylized partial equilibrium model (the open source impacts of REDD incentives spreadsheet; OSIRIS). The model explicitly incorporates national incentives to participate in an international REDD mechanism as well as international leakage of deforestation emissions. Our results show that a REDD mechanism can provide cost-efficient climate change mitigation benefits under a broad range of reference level designs. We find that the most effective reference level designs balance incentives to reduce historically high deforestation emissions with incentives to maintain historically low deforestation emissions. Estimates of emission reductions under REDD depend critically on the degree to which demand for tropical frontier agriculture generates leakage. This underscores the potential importance to REDD of complementary strategies to supply agricultural needs outside of the forest frontier.

Comparing climate and cost impacts of reference levels for reducing emissions from deforestation

International Nuclear Information System (INIS)

Busch, Jonah; Strassburg, Bernardo; Cattaneo, Andrea; Lubowski, Ruben; Bruner, Aaron; Rice, Richard; Boltz, Frederick; Creed, Anna; Ashton, Ralph

2009-01-01

The climate benefit and economic cost of an international mechanism for reducing emissions from deforestation and degradation (REDD) will depend on the design of reference levels for crediting emission reductions. We compare the impacts of six proposed reference level designs on emission reduction levels and on cost per emission reduction using a stylized partial equilibrium model (the open source impacts of REDD incentives spreadsheet; OSIRIS). The model explicitly incorporates national incentives to participate in an international REDD mechanism as well as international leakage of deforestation emissions. Our results show that a REDD mechanism can provide cost-efficient climate change mitigation benefits under a broad range of reference level designs. We find that the most effective reference level designs balance incentives to reduce historically high deforestation emissions with incentives to maintain historically low deforestation emissions. Estimates of emission reductions under REDD depend critically on the degree to which demand for tropical frontier agriculture generates leakage. This underscores the potential importance to REDD of complementary strategies to supply agricultural needs outside of the forest frontier.

Assessment of the emissions and air quality impacts of biomass and biogas use in California.

Science.gov (United States)

Carreras-Sospedra, Marc; Williams, Robert; Dabdub, Donald

2016-02-01

It is estimated that there is sufficient in-state "technically" recoverable biomass to support nearly 4000 MW of bioelectricity generation capacity. This study assesses the emissions of greenhouse gases and air pollutants and resulting air quality impacts of new and existing bioenergy capacity throughout the state of California, focusing on feedstocks and advanced technologies utilizing biomass resources predominant in each region. The options for bioresources include the production of bioelectricity and renewable natural gas (NG). Emissions of criteria pollutants and greenhouse gases are quantified for a set of scenarios that span the emission factors for power generation and the use of renewable natural gas for vehicle fueling. Emissions are input to the Community Multiscale Air Quality (CMAQ) model to predict regional and statewide temporal air quality impacts from the biopower scenarios. With current technology and at the emission levels of current installations, maximum bioelectricity production could increase nitrogen oxide (NOx) emissions by 10% in 2020, which would cause increases in ozone and particulate matter concentrations in large areas of California. Technology upgrades would achieve the lowest criteria pollutant emissions. Conversion of biomass to compressed NG (CNG) for vehicles would achieve comparable emission reductions of criteria pollutants and minimize emissions of greenhouse gases (GHG). Air quality modeling of biomass scenarios suggest that applying technological changes and emission controls would minimize the air quality impacts of bioelectricity generation. And a shift from bioelectricity production to CNG production for vehicles would reduce air quality impacts further. From a co-benefits standpoint, CNG production for vehicles appears to provide the best benefits in terms of GHG emissions and air quality. This investigation provides a consistent analysis of air quality impacts and greenhouse gas emissions for scenarios examining

Mécanique des sols et des roches

CERN Document Server

Vullier, Laurent; Zhao, Jian

2016-01-01

La mécanique des sols et la mécanique des roches sont des disciplines généralement traitées séparément dans la littérature. Pour la première fois, un traité réunit ces deux spécialités, en intégrant également les connaissances en lien avec les écoulements souterrains et les transferts thermiques. A la fois théorique et pratique, cet ouvrage propose tout d'abord une description détaillée de la nature et de la composition des sols et des roches, puis s'attache à la modélisation de problèmes aux conditions limites et présente les essais permettant de caractériser les sols et les roches, tant d'un point de vue mécanique qu'hydraulique et thermique. La problématique des sols non saturés et des écoulements multiphasiques est également abordée. Une attention particulière est portée aux lois de comportement mécanique et à la détermination de leurs paramètres par des essais in situ et en laboratoire, et l'ouvrage offre également une présentation détaillée des systèmes de classi...

Study of secondary electronic emission in some piezo-electric materials: application to ultrasonic visualization; Etude de l'emission electronique secondaire de quelques materiaux piezoelectriques: application a la visualisation ultrasonore

Energy Technology Data Exchange (ETDEWEB)

Marini, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

Methods allowing the visualization of acoustic images appear at the moment to be of great interest in the field of non-destructive testing as well as in that of underwater detection. In order to carry out certain calculations on the operation of an ultrasonic camera, it has been necessary to study the secondary electron emission of some piezoelectric materials liable to be incorporated into the equipment. The secondary electron emission of insulators is a rather complex phenomenon; in order to find a rational explanation for the observations made, a theory has been developed for the energy spectrum of the emitted electrons. The experimental results of this work have then been used to build an ultrasonic visualization installation. Some examples of acoustic images which have been visualized are also presented. (author) [French] Les methodes qui permettent de visualiser des images acoustiques trouvent a l'heure actuelle un grand interet dans le domaine du controle non destructif comme dans celui de la detection sous-marine. De maniere a effectuer certains calculs sur le fonctionnement d'une camera ultrasons, il a ete necessaire d'etudier l'emission electronique secondaire de quelques materiaux piezoelectriques susceptibles d'etre utilises dans sa construction. L'emission electronique secondaire des isolants est un phenomene assez complexe et de maniere a trouver des explications coherentes aux observations effectuees, une theorie du spectre energetique des electrons emis a ete elaboree. Une installation de visualisation ultrasonore a alors ete realisee a partir des donnees experimentales de cette etude. Quelques exemples d'images acoustiques visualisees par cette methode sont egalement presentees. (auteur)

Impact of biogenic emission uncertainties on the simulated response of ozone and fine particulate matter to anthropogenic emission reductions.

Science.gov (United States)

Hogrefe, Christian; Isukapalli, Sastry S; Tang, Xiaogang; Georgopoulos, Panos G; He, Shan; Zalewsky, Eric E; Hao, Winston; Ku, Jia-Yeong; Key, Tonalee; Sistla, Gopal

2011-01-01

The role of emissions of volatile organic compounds and nitric oxide from biogenic sources is becoming increasingly important in regulatory air quality modeling as levels of anthropogenic emissions continue to decrease and stricter health-based air quality standards are being adopted. However, considerable uncertainties still exist in the current estimation methodologies for biogenic emissions. The impact of these uncertainties on ozone and fine particulate matter (PM2.5) levels for the eastern United States was studied, focusing on biogenic emissions estimates from two commonly used biogenic emission models, the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and the Biogenic Emissions Inventory System (BEIS). Photochemical grid modeling simulations were performed for two scenarios: one reflecting present day conditions and the other reflecting a hypothetical future year with reductions in emissions of anthropogenic oxides of nitrogen (NOx). For ozone, the use of MEGAN emissions resulted in a higher ozone response to hypothetical anthropogenic NOx emission reductions compared with BEIS. Applying the current U.S. Environmental Protection Agency guidance on regulatory air quality modeling in conjunction with typical maximum ozone concentrations, the differences in estimated future year ozone design values (DVF) stemming from differences in biogenic emissions estimates were on the order of 4 parts per billion (ppb), corresponding to approximately 5% of the daily maximum 8-hr ozone National Ambient Air Quality Standard (NAAQS) of 75 ppb. For PM2.5, the differences were 0.1-0.25 microg/m3 in the summer total organic mass component of DVFs, corresponding to approximately 1-2% of the value of the annual PM2.5 NAAQS of 15 microg/m3. Spatial variations in the ozone and PM2.5 differences also reveal that the impacts of different biogenic emission estimates on ozone and PM2.5 levels are dependent on ambient levels of anthropogenic emissions.

Amélioration des performances environnementales des pratiques viticoles et analyse des risques pour la qualité du raisin : étape vers l’écoqualiconception©

Directory of Open Access Journals (Sweden)

Beauchet Sandra

2017-01-01

Full Text Available L’évolution des itinéraires techniques viticoles (ITKv vers un plus grand respect de l’environnement passe par une évaluation de leurs performances environnementales. Dans un contexte de gestion durable, plusieurs autres facteurs sont à prendre en compte, notamment le risque de modification de la qualité des raisins issus de ces ITKv. Les résultats d’évaluation environnementale par la méthode d’Analyse du Cycle de Vie (ACV ainsi que l’évaluation de la qualité du raisin s’appuient sur beaucoup données. Ce travail montre l’intérêt d’une méthode d’évaluation multicritère conjointe « environnement et qualité », dans le processus de changement de pratiques pour une amélioration des performances. Les résultats obtenus sur 5 ITKv montrent des différences de notes entre les 2 millésimes étudiés et des pratiques ont été identifiées pour leurs forts impacts sur les résultats ACV. Des propositions théoriques de changement de pratiques sont testées sur l’un des ITKv. Ces propositions améliorent les notes environnementales finales de +0,15 points à +0,77 points (/10 quand elles sont mises en œuvre séparément et +2,29 points (/10 en étant combinées. Un modèle explicatif de la qualité du raisin permet de vérifier que les nouvelles pratiques ne peuvent potentiellement pas altérer la qualité du raisin. La méthode d’évaluation conjointe CONTRA-QUALENVIC adaptée à la viticulture montre ici qu’elle peut être une aide à l’amélioration des ITKv.

Impacts of Lowered Urban Air Temperatures on Precursor Emission and Ozone Air Quality.

Science.gov (United States)

Taha, Haider; Konopacki, Steven; Akbari, Hashem

1998-09-01

Meteorological, photochemical, building-energy, and power plant simulations were performed to assess the possible precursor emission and ozone air quality impacts of decreased air temperatures that could result from implementing the "cool communities" concept in California's South Coast Air Basin (SoCAB). Two pathways are considered. In the direct pathway, a reduction in cooling energy use translates into reduced demand for generation capacity and, thus, reduced precursor emissions from electric utility power plants. In the indirect pathway, reduced air temperatures can slow the atmospheric production of ozone as well as precursor emission from anthropogenic and biogenic sources. The simulations suggest small impacts on emissions following implementation of cool communities in the SoCAB. In summer, for example, there can be reductions of up to 3% in NO x emissions from in-basin power plants. The photochemical simulations suggest that the air quality impacts of these direct emission reductions are small. However, the indirect atmospheric effects of cool communities can be significant. For example, ozone peak concentrations can decrease by up to 11% in summer and population-weighted exceedance exposure to ozone above the California and National Ambient Air Quality Standards can decrease by up to 11 and 17%, respectively. The modeling suggests that if these strategies are combined with others, such as mobile-source emission control, the improvements in ozone air quality can be substantial.

Emission abatement: Untangling the impacts of the EU ETS and the economic crisis

International Nuclear Information System (INIS)

Bel, Germà; Joseph, Stephan

2015-01-01

In this study we use historical emission data from installations under the European Union Emissions Trading System (EU ETS) to evaluate the impact of this policy on greenhouse gas emissions during the first two trading phases (2005–2012). As such the analysis seeks to disentangle two causes of emission abatement: that attributable to the EU ETS and that attributable to the economic crisis that hit the EU in 2008/09. To do so, we use a dynamic panel data approach. Our results suggest that, by far, the biggest share of abatement was attributable to the effects of the economic crisis. This finding has serious implications for future policy adjustments affecting core elements of the EU ETS, including the distribution of EU emission allowances. - Highlights: • We untangle the effects of the EU ETS from those of the economic crisis on industrial emission abatement. • The empirical analysis uses verified emission data instead of estimated emission data. • Abatement of emissions in EU in the last years has been mainly due to the impact of the economic crisis. • Low level of abatement attributable to the EU ETS suggests that important changes must be made in environmental policy

Impact of increasing ship emissions on air quality and deposition over Europe by 2030

Energy Technology Data Exchange (ETDEWEB)

Collins, Bill; Sanderson, Michael G.; Johnson, Colin E. [Met Office Hadley Centre for Climate Change, Exeter (United Kingdom)

2009-07-01

A global chemistry-transport model has been used to study the effect of shipping emissions on air quality and ecosystems over Europe, through changes in surface ozone and surface sulphate aerosols, and changes in the deposition of sulphur and oxidised nitrogen. Scenarios are chosen to determine the impact of current (2000) shipping emissions, and the combined impact of changes in land-based and shipping emissions by 2030. The effects of shipping on ozone are small, compared to land-based emissions changes, and can be both positive and negative. Due to the non-linear nature of ozone chemistry, the effects of shipping depend on the magnitude of the emission change, and on the choice of scenario for the land-based emissions. The effects on sulphate aerosol levels and deposition fluxes of sulphate aerosols and oxidised nitrogen species are larger, and are comparable to expected changes in land-based emissions. This is particularly true for SO{sub 2} emissions from shipping. SO{sub 2} has a sufficiently short lifetime that most of the impacts are felt within the European region, although much of that is over the sea. The increase in sulphate aerosols and sulphur deposition due to the SO{sub 2} from shipping will offset 75 % of the benefits in air quality that would be expect from land-based emission controls under the SRES A2 scenario. (orig.)

Évaluation des pratiques agricoles des légumes feuilles : le cas des ...

African Journals Online (AJOL)

SARAH

30 sept. 2017 ... ... de Biochimie et Immunologie Appliquée, Centre de Recherche en Sciences Biologiques, Alimentaires et .... l'intoxication des agriculteurs et des consommateurs, ... source d'alimentation en eau et au pouvoir d'achat des.

Modelisation des effets physico-techniques pour la conception des ...

African Journals Online (AJOL)

automatisation dans les installations industrielles a besoin d'une régulation automatique des commandes des processus technologiques pour lesquelles certaines contraintes sont à relever compte tenu des exigences des innovations scientifiques de ...

La rentabilité des immeubles "verts"

OpenAIRE

Thalmann, Philippe

2016-01-01

Les immeubles verts ont un faible impact environnemental tout en offrant aussi de bonnes conditions sociales, voire des gains environnementaux (qualité de l'air, biodiversité). Ils sont donc exemplaires dans divers domaines: énergie, utilisation du sol, biodiversité, matériaux. Est-ce que cela implique forcément un sur-coût? Est-il possible de rentabiliser ce sur-coût ou le développer doit-il se contenter des retombées favorables pour l'environnement et la société?

Fundamental study of ionization and dissociation processes caused by electron impact in aromatic molecules; application of the quasi-equilibrium theory to phenanthrene and to methylphenanthrenes; Etudes fondamentales des processus d'ionisation et de dissociation des molecules aromatiques par impact electronique et application de la theorie du quasi-equilibre au phenanthrene et aux methyl-phenanthrenes

Energy Technology Data Exchange (ETDEWEB)

Nounou, P [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1969-07-01

behaviour under ionizing radiations of the studied compounds. (author) [French] La theorie du quasi-equilibre n'a ete appliquee jusqu'a present qu'a la seule famille des hydrocarbures aliphatiques en chaine droite. Nous avons donc essaye de l'etendre au phenanthrene et au methyl-phenantrene, c'est-a-dire, d'une part a des molecules aromatiques et d'autre part a des molecules ayant un tres grand nombre de degres de liberte. Dans une premiere partie nous avons tente d'interpreter de facon methodique les processus d'ionisation et de dissociation des molecules phenanthreniques. Cette premiere etude experimentale du comportement des composes sous impact electronique, et son interpretation, nous ont fourni de precieux renseignements sur de profonds changements de structure des ions moleculaires et fragmentaires, voire d'excitation des molecules etudiees. L'etude approfondie des pics metastables a ensuite confirme les processus de dissociation precedents, tout en precisant certaines grandeurs thermodynamiques relatives aux reactions de decomposition. Etudes des processus d'ionisation, puis de dissociation, et enfin des pics metastables, constituent les trois temps d'une methode generale d'interpretation de la fragmentation en spectrometrie de masse. Pour donner a cette methode son assise theorique nous avons ete amenes a elaborer les diagrammes moleculaires de chacun des composes etudies, montrant ainsi l'aide efficace que peut presenter la Mecanique Quantique pour l'etude des etats excites et ionises. Dans une seconde partie, nous avons calcule les spectres de masse du phenanthrene et des methyl-phenanthrenes a partir des expressions des constantes de reaction donnees par ROSENSTOCK. Pour ce faire, nous avons propose de nouvelles methodes de calcul des facteurs de frequence, tant pour les molecules aliphatiques que les aromatiques. Si le bon accord generalement observe entre le calcul et l'experience ne peut etre attribue a coup sur a l'exactitude de la theorie, il n'en demontre

Vecteurs Singuliers des Theories des Champs Conformes Minimales

Science.gov (United States)

Benoit, Louis

En 1984 Belavin, Polyakov et Zamolodchikov revolutionnent la theorie des champs en explicitant une nouvelle gamme de theories, les theories quantiques des champs bidimensionnelles invariantes sous les transformations conformes. L'algebre des transformations conformes de l'espace-temps presente une caracteristique remarquable: en deux dimensions elle possede un nombre infini de generateurs. Cette propriete impose de telles conditions aux fonctions de correlations qu'il est possible de les evaluer sans aucune approximation. Les champs des theories conformes appartiennent a des representations de plus haut poids de l'algebre de Virasoro, une extension centrale de l'algebre conforme du plan. Ces representations sont etiquetees par h, le poids conforme de leur vecteur de plus haut poids, et par la charge centrale c, le facteur de l'extension centrale, commune a toutes les representations d'une meme theorie. Les theories conformes minimales sont constituees d'un nombre fini de representations. Parmi celles-ci se trouvent des theories unitaires dont les representation forment la serie discrete de l'algebre de Virasoro; leur poids h a la forme h_{p,q}(m)=[ (p(m+1) -qm)^2-1] (4m(m+1)), ou p,q et m sont des entiers positifs et p+q= 2. Ces representations possedent un sous-espace invariant engendre par deux sous-representations avec h_1=h_{p,q} + pq et h_2=h_{p,q} + (m-p)(m+1-q) dont chacun des vecteurs de plus haut poids portent le nom de vecteur singulier et sont notes respectivement |Psi _{p,q}> et |Psi_{m-p,m+1-q}>. . Les theories super-conformes sont une version super-symetrique des theories conformes. Leurs champs appartiennent a des representation de plus haut poids de l'algebre de Neveu-Schwarz, une des deux extensions super -symetriques de l'algebre de Virasoro. Les theories super -conformes minimales possedent la meme structure que les theories conformes minimales. Les representations sont elements de la serie h_{p,q}= [ (p(m+2)-qm)^2-4] /(8m(m+2)) ou p,q et m sont

Comparison of secondary ion emission yields for poly-tyrosine between cluster and heavy ion impacts

International Nuclear Information System (INIS)

Hirata, K.; Saitoh, Y.; Chiba, A.; Yamada, K.; Takahashi, Y.; Narumi, K.

2010-01-01

Emission yields of secondary ions necessary for the identification of poly-tyrosine were compared for incident ion impacts of energetic cluster ions (0.8 MeV C 8 + , 2.4 MeV C 8 + , and 4.0 MeV C 8 + ) and swift heavy monoatomic molybdenum ions (4.0 MeV Mo + and 14 MeV Mo 4+ ) with similar mass to that of the cluster by time-of-flight secondary ion mass analysis combined with secondary ion electric current measurements. The comparison revealed that (1) secondary ion emission yields per C 8 + impact increase with increasing incident energy within the energy range examined, (2) the 4.0 MeV C 8 + impact provides higher emission yields than the impact of the monoatomic Mo ion with the same incident energy (4.0 MeV Mo + ), and (3) the 2.4 MeV C 8 + impact exhibits comparable emission yields to that for the Mo ion impact with higher incident energy (14 MeV Mo 4+ ). Energetic cluster ion impacts effectively produce the characteristic secondary ions for poly-tyrosine, which is advantageous for highly sensitive amino acid detection in proteins using time-of-flight secondary ion mass analysis.

The Impact of Groupement des Cartes Bancaires on Competition Law Enforcement

Directory of Open Access Journals (Sweden)

Piero Fattori

2015-10-01

Full Text Available The Groupement des Cartes bancaires represents a key judgment for competition enforcement, as it provides helpful clarification on the notion of “restriction by object” and on the judicial standard of review of Commission decisions. As of the first aspect, the ruling limited the restrictions by object to those which by their very nature and on the basis of the experience reveal a sufficient degree of harm to competition. On the standard required to the Court in reviewing competition decisions, the ECJ underlines the necessity of carrying out a full review, specifying that the presence of economic issues should not dispense the Court with an in-depth review of the law and the facts. The principles expressed in the judgment could have a great impact also at national level, where it could provide useful guidance both to Italian competition authority and to the Administrative Courts.

The Emissions Impacts of Varied Energy Storage Operational Objectives Across Regions

Energy Technology Data Exchange (ETDEWEB)

Barrett, Emily L.; Thayer, Brandon L.; Studarus, Karen E.; Pal, Seemita

2017-11-15

The emissions consequences of smart grid technologies can be significant but are not always intuitive. This is particularly true in the implementation of energy storage (ES) systems that are being increasingly adopted to integrate more intermittent renewable generation, to reduce peak demand, and to participate in energy markets. Both the location of the ES system within the grid and the way it is operated will dictate its resulting impacts. The Grid Project Impact Quantification tool can provide insight into some of the emissions implications of hypothetical ES systems for a variety of operational objectives in diverse locations within the United States.

External costs of atmospheric Pb emissions: valuation of neurotoxic impacts due to inhalation

Directory of Open Access Journals (Sweden)

Frohn Lise

2010-02-01

Full Text Available Abstract Background The Impact Pathway Approach (IPA is an innovative methodology to establish links between emissions, related impacts and monetary estimates. Only few attempts have so far been presented regarding emissions of metals; in this study the external costs of airborne lead (Pb emissions are assessed using the IPA. Exposure to Pb is known to provoke impacts especially on children's cognition. As cognitive abilities (measured as IQ, intelligence quotient are known to have implications for lifetime income, a pathway can be established leading from figures for Pb emissions to the implied loss in earnings, and on this basis damage costs per unit of Pb emission can be assessed. Methods Different types of models are here linked. It is relatively straightforward to establish the relationship between Pb emissions and consequent increase in air-Pb concentration, by means of a Gaussian plume dispersion model (OML. The exposed population can then be modelled by linking the OML-output to population data nested in geo-referenced grid cells. Less straightforward is to establish the relationship between exposure to air-Pb concentrations and the resulting blood-Pb concentration. Here an Age-Dependent Biokinetic Model (ADBM for Pb is applied. On basis of previous research which established links between increases in blood-Pb concentrations during childhood and resulting IQ-loss we arrive at our results. Results External costs of Pb airborne emissions, even at low doses, in our site are in the range of 41-83 €/kg emitted Pb, depending on the considered meteorological year. This estimate applies only to the initial effects of air-Pb, as our study does not address the effects due to the Pb environmental-accumulation and to the subsequent Pb re-exposure. These are likely to be between one and two orders of magnitude higher. Conclusions Biokinetic modelling is a novel tool not previously included when applying the IPA to explore impacts of Pb emissions

The impact of residential combustion emissions on atmospheric aerosol, human health, and climate

Directory of Open Access Journals (Sweden)

E. W. Butt

2016-01-01

Full Text Available Combustion of fuels in the residential sector for cooking and heating results in the emission of aerosol and aerosol precursors impacting air quality, human health, and climate. Residential emissions are dominated by the combustion of solid fuels. We use a global aerosol microphysics model to simulate the impact of residential fuel combustion on atmospheric aerosol for the year 2000. The model underestimates black carbon (BC and organic carbon (OC mass concentrations observed over Asia, Eastern Europe, and Africa, with better prediction when carbonaceous emissions from the residential sector are doubled. Observed seasonal variability of BC and OC concentrations are better simulated when residential emissions include a seasonal cycle. The largest contributions of residential emissions to annual surface mean particulate matter (PM2.5 concentrations are simulated for East Asia, South Asia, and Eastern Europe. We use a concentration response function to estimate the human health impact due to long-term exposure to ambient PM2.5 from residential emissions. We estimate global annual excess adult (>  30 years of age premature mortality (due to both cardiopulmonary disease and lung cancer to be 308 000 (113 300–497 000, 5th to 95th percentile uncertainty range for monthly varying residential emissions and 517 000 (192 000–827 000 when residential carbonaceous emissions are doubled. Mortality due to residential emissions is greatest in Asia, with China and India accounting for 50 % of simulated global excess mortality. Using an offline radiative transfer model we estimate that residential emissions exert a global annual mean direct radiative effect between −66 and +21 mW m−2, with sensitivity to the residential emission flux and the assumed ratio of BC, OC, and SO2 emissions. Residential emissions exert a global annual mean first aerosol indirect effect of between −52 and −16 mW m−2, which is sensitive to the

Utilisation sans risque des eaux usées, des excréta et des eaux ...

International Development Research Centre (IDRC) Digital Library (Canada)

Les responsables de ce projet piloteront l'application et l'adaptation des principes directeurs relatifs à l'utilisation sans risque des eaux usées, des excreta et des eaux grises en agriculture et en aquaculture (Guidelines for the Safe Use of Wastewater, Excreta and Greywater in Agriculture and Aquaculture), que ...

Introduction of a method for presenting health-based impacts of the emission from products, based on emission measurements of materials used in manufacturing of the products

Energy Technology Data Exchange (ETDEWEB)

Jørgensen, Rikke Bramming, E-mail: rikke.jorgensen@iot.ntnu.no

2013-11-15

A method for presenting the health impact of emissions from furniture is introduced, which could be used in the context of environmental product declarations. The health impact is described by the negative indoor air quality potential, the carcinogenic potential, the mutagenic and reprotoxic potential, the allergenic potential, and the toxicological potential. An experimental study of emissions from four pieces of furniture is performed by testing both the materials used for production of the furniture and the complete piece of furniture, in order to compare the results gained by adding emissions of material with results gained from testing the finished piece of furniture. Calculating the emission from a product based on the emission from materials used in the manufacture of the product is a new idea. The relation between calculated results and measured results from the same products differ between the four pieces of furniture tested. Large differences between measured and calculated values are seen for leather products. More knowledge is needed to understand why these differences arise. Testing materials allows us to compare different suppliers of the same material. Four different foams and three different timber materials are tested, and the results vary between materials of the same type. If the manufacturer possesses this type of knowledge of the materials from the subcontractors it could be used as a selection criterion according to production of low emission products. -- Highlights: • A method for presenting health impact of emissions is introduced. • An experimental study of emissions from four pieces of furniture is performed. • Health impact is calculated based on sum of contribution from the materials used. • Calculated health impact is compared to health impact of the manufactured product. • The results show that health impact could be useful in product development and for presentation in EPDs.

Particle Reduction Strategies - PAREST. Traffic emission modelling. Model comparision and alternative scenarios. Sub-report; Strategien zur Verminderung der Feinstaubbelastung - PAREST. Verkehrsemissionsmodellierung. Modellvergleich und Alternative Szenarien. Teilbericht

Energy Technology Data Exchange (ETDEWEB)

Kugler, Ulrike; Theloke, Jochen [Stuttgart Univ. (Germany). Inst. fuer Energiewirtschaft und Rationelle Energieanwendung (IER); Joerss, Wolfram [Institut fuer Zukunftsstudien und Technologiebewertung gGmbH (IZT), Berlin (Germany)

2013-06-15

The modeling of the reference scenario and the various reduction scenarios in PAREST was based on the Central System of Emissions (CSE) (CSE, 2007). Emissions from road traffic were calculated by using the traffic emission model TREMOD (Knoerr et al., 2005) and fed into the CSE. The version TREMOD 4.17 has been used. The resulting emission levels in PAREST reference scenario were supplemented by the emission-reducing effect of the implementation of the future Euro 5 and 6 emission standards for cars and light commercial vehicles and Euro VI for heavy commercial vehicles in combination with the truck toll extension. [German] Die Modellierung des Referenzszenarios und der verschiedenen Minderungsszenarien in PAREST erfolgte auf Grundlage des Zentralen System Emissionen (ZSE) (ZSE, 2007). Emissionen aus dem Strassenverkehr wurden mit Hilfe des Verkehrsemissionsmodells TREMOD (Knoerr et al., 2005) berechnet und in das ZSE eingespeist. Dabei wurde die Version TREMOD 4.17 verwendet. Die daraus resultierenden Emissionsmengen wurden im PAREST-Referenzszenario um die emissionsmindernde Wirkung der zukuenftigen Implementierung der Abgasnormen Euro 5 und 6 fuer Pkw und leichte Nutzfahrzeuge sowie Euro VI fuer schwere Nutzfahrzeuge in Kombination einer Erweiterung der Lkw-Maut ergaenzt. Die Berechnung der Emissionen des Referenzszenarios wurde auf Grundlage des Inlandsprinzips sowie des Energiebilanzprinzips durchgefuehrt. Die auf dieser Grundlage berechneten Emissionen fuer das Basisjahr 2005 und fuer die Referenzjahre 2010, 2015 und 2020 unterscheiden sich teilweise erheblich von den mit Hilfe des Modells TREMOVE (dem von der EU Kommission verwendeten Modell fuer mobile Quellen) berechneten Emissionen.

Mesurer le droit de participer à la vie culturelle: le développement des indicateurs

NARCIS (Netherlands)

Donders, Y.; Bouchard, J.; Gandolfi, S.; Meyer-Bisch, P.

2013-01-01

Dans les domaines des droits de l'homme, de la culture et du développement, des cadres et mécanismes sont développés afin de mesurer et de qualifier les relations entre ces domaines et leur impact sur la vie des individus en des communautés. Les indicateurs constituent un élément important de ces

La microscopie ionique analytique des tissus biologiques

Science.gov (United States)

Galle, P.

Proposed in 1960 by R. Castaing and G. Slodzian, secondary ion emission microanalysis is a microanalytical method which is now largely used for the study of inert material. The instrument called the analytical ion microscope can also be used for the study of biological spécimens ; images representing the distribution of a given stable or radioactive isotope in a tissue section are obtained with a resolution of 0.5 μm. Among the characteristics of this method, two are of particular interest in biological research : its capacity for isotopic analysis and its very high sensitivity which makes possible for the first time a chemical analysis of element at a very low or even at a trace concentration in a microvolume. Proposé en 1960 par R. Castaing et G. Slodzian, la microanalyse par émission ionique secondaire est une méthode qui permet, entre autre, d'obtenir des images représentant la distribution des isotopes présents à la surface d'un échantillon solide avec une résolution de 0,5 μm. D'intérêt très général, cette méthode a été d'abord largement utilisée pour l'étude des matériaux inertes. Elle offre en outre des possibilités entièrement nouvelles dans le domaine de la recherche biomédicale. L'instrument réalisé, le microscope ionique analytique présente deux caractéristiques particulièrement intéressantes pour la biologie : la possibilité d'analyse isotopique, et l'extrême sensibilité permettant de détecter et de localiser dans une coupe histologique des éléments à des concentrations très faibles voire à l'état de trace.

ANALYSE DES PERCEPTIONS LOCALES ET DES FACTEURS ...

African Journals Online (AJOL)

AISA

1Faculté des Sciences Agronomiques (FSA), Université d'Abomey-Calavi (UAC), 01 BP 526 Cotonou Bénin. Email : cgbemavo@yahoo.fr. 2Institut National des Recherches Agricoles du Bénin, Centre de Recherches Agricoles d'Agonkanmey (CRA-A),. Laboratoire des Sciences du Sol, Eau et Environnement (LSSEE).

New methods and applications in emission spectroscopy (1960); Methodes et applications nouvelles en spectroscopie d'emission (1960)

Energy Technology Data Exchange (ETDEWEB)

Baudin, G [Commissariat a l' Energie Atomique, Grenoble (France).Centre d' Etudes Nucleaires

1960-07-01

Emission spectroscopy, are already well-established instrumental analytical technique, has in recent years known important developments. Two mains factors are responsible; firstly the demands of metallurgy for purer and purer materials or alloys which are increasingly complex and difficult to analyse by chemical means; secondly, progress in optics, especially in the production of gratings, and in electronics in the field of photomultiplier tubes. We will not here catalogue all the new applications and methods, but we will consider a few amongst the most representative outside the conventional field. (author) [French] La spectroscopie d'emission, technique analytique instrumentale deja ancienne, a pris, depuis quelques annees, une extension notable. Deux facteurs principaux ont contribue a ce succes: d'une part, l'exigence de la metallurgie en materiaux de plus en plus pur ou en alliages de plus en plus complexes, difficiles a analyser chimiquement, d'autre part, les progres realises en optique, principalement dans la fabrication des reseaux, et en electronique dans le domaine des tubes photomultiplicateurs. Nous ne ferons pas ici le recensement de toutes les applications ou methodes nouvelles, mais nous en choisirons quelques unes des plus representatives hors du domaine classique. (auteur)

variabilite des productions et des revenus des exploitations

African Journals Online (AJOL)

3Centre de coopération internationale en recherche agronomique pour le développement (CIRAD), UMR Innovation,. Montpellier, France. Doubangolo COULIBALY, Email kone_b@yahoo.fr. RESUME. La durabilité des systèmes de production à base de coton dans un contexte de variabilité des prix aux producteurs et de ...

Le statut vitaminique des individus et des populations…

Directory of Open Access Journals (Sweden)

Icart Jean-Claude

2000-05-01

Full Text Available Comme le souligne un récent rapport du Haut comité de santé publique, le statut vitaminique des individus et des populations demeure une question d’actualité. Si les études ne révèlent plus de signes évocateurs de carence, au plus des problèmes de déficiences pour certains groupes à risque, des interrogations, demeurent malgré le contexte d’abondance, concernant la couverture des besoins, laquelle pourrait s’avérer inférieure aux valeurs considérées comme satisfaisantes.

Application des TIC à l'atténuation des effets des catastrophes dans ...

International Development Research Centre (IDRC) Digital Library (Canada)

L'Amérique centrale est souvent aux prises avec des inondations et des ... (SIG) et de traitement des images, afin de cartographier les dangers et de modéliser les ... de l'Institut d'étude du développement international de l'Université McGill.

Environmental impacts of genetically modified (GM) crop use 1996-2014: Impacts on pesticide use and carbon emissions.

Science.gov (United States)

Brookes, Graham; Barfoot, Peter

2016-04-02

This paper updates previous assessments of important environmental impacts associated with using crop biotechnology in global agriculture. It focuses on the environmental impacts associated with changes in pesticide use and greenhouse gas emissions arising from the use of GM crops since their first widespread commercial use in the mid 1990s. The adoption of GM insect resistant and herbicide tolerant technology has reduced pesticide spraying by 581.4 million kg (-8.2%) and, as a result, decreased the environmental impact associated with herbicide and insecticide use on these crops (as measured by the indicator, the Environmental Impact Quotient [EIQ]) by18.5%. The technology has also facilitated important cuts in fuel use and tillage changes, resulting in a significant reduction in the release of greenhouse gas emissions from the GM cropping area. In 2014, this was equivalent to removing nearly 10 million cars from the roads.

Environmental impacts of genetically modified (GM) crop use 1996-2015: Impacts on pesticide use and carbon emissions.

Science.gov (United States)

Brookes, Graham; Barfoot, Peter

2017-04-03

This paper updates previous assessments of important environmental impacts associated with using crop biotechnology in global agriculture. It focuses on the environmental impacts associated with changes in pesticide use and greenhouse gas emissions arising from the use of GM crops since their first widespread commercial use in the mid-1990s. The adoption of GM insect resistant and herbicide tolerant technology has reduced pesticide spraying by 618.7 million kg (-8.1%) and, as a result, decreased the environmental impact associated with herbicide and insecticide use on these crops (as measured by the indicator, the Environmental Impact Quotient (EIQ)) by18.6%. The technology has also facilitated important cuts in fuel use and tillage changes, resulting in a significant reduction in the release of greenhouse gas emissions from the GM cropping area. In 2015, this was equivalent to removing 11.9 million cars from the roads.

Impact of biogenic emissions on feedbacks in the climate system

Science.gov (United States)

Krüger, Olaf

2017-04-01

Impact of biogenic emissions on feedbacks in the climate system Bio-geophysical feedback between marine or continental ecosystems and the atmosphere potentially can alter climate change. A prominent feedback loop which is under discussion since 1983 bases on the emission of biologically produced gases - molecular oxygen, sulphur containing compounds and possibly isoprene, supersaturated in oceanic waters - into the marine troposphere. These by-products of phytoplankton metabolism lead to aerosol production and procure sustained influence on climate via modulation of cloud optical properties. In this contribution some findings related to the above mentioned climate processes are presented with special emphasis on marine ecosystems. A comparison of marine and continental ecosystems is made and different processes with major impact on feedbacks in the climate system are discussed.

Etude paramétrique des effets de la stratification de la flamme sur les émissions d'oxydes d'azote (première partie Parametric Study of Statification Effects on Nitric Oxyde Emissions from Flam (Part One

Directory of Open Access Journals (Sweden)

De Soete G.

2006-11-01

actuelles concernant les mécanismes cinétiques du NO thermique et du fuel-NO. Les conséquences des différentes modalités de stratification sur le rendement thermique de la combustion ont également été étudiées. Charge staging effects on thermal NO and fuel-NO emissions are studied on premixed laminar steady and unsteady flames. Two stratification modes are considered. In the first mode, called the juxtaposition mode, the primary combustion zones, corresponding ta the individual fractions of the stratified mixture, are situated contiguously on the same plane; in the second mode, called the succession mode, they are situated on successive planes, with a primary combustion zone developing in the downstream combustion products of the other. Nitric oxide emissions are measured for stratified flames and compared with those coming from flames hoving the same overall composition and burning under identical conditions but without stratification. The results show that a distinction has ta be made between two types of stratification effects. The primary effect is the simple consequence of subdividing the flame into a certain number of individual primary combustion zones (characterized by different equivalence ratios ; it is revealed by the addition of the individual emissions from the respective mixture fractions. The total effect of the stratification is limited solely ta this primary effect, in sa far as the nitric oxide rates vanish, after the combustion products issuing from the different mixture fractions become mixed. This obviously applies in the case of unsteady flames stratified in the succession mode; charge stratification then results either in an increase or a decrease in nitric oxide emissions compared with those of the corresponding non-stratified flames, depending on the overall equivalence ratio and the degree of stratification. Whenever combustion products issuing from a given primary combustion zone are introduced into another combustion zone of the

Environmental impacts of food trade via resource use and greenhouse gas emissions

International Nuclear Information System (INIS)

Dalin, Carole; Rodríguez-Iturbe, Ignacio

2016-01-01

Agriculture will need to significantly intensify in the next decades to continue providing essential nutritive food to a growing global population. However, it can have harmful environmental impacts, due to the use of natural and synthetic resources and the emission of greenhouse gases, which alter the water, carbon and nitrogen cycles, and threaten the fertility, health and biodiversity of landscapes. Because of the spatial heterogeneity of resource productivity, farming practices, climate, and land and water availability, the environmental impact of producing food is highly dependent on its origin. For this reason, food trade can either increase or reduce the overall environmental impacts of agriculture, depending on whether or not the impact is greater in the exporting region. Here, we review current scientific understanding of the environmental impacts of food trade, focusing on water and land use, pollution and greenhouse gas emissions. In the case of water, these impacts are mainly beneficial. However, in the cases of pollution and greenhouse gas emissions, this conclusion is not as clear. Overall, there is an urgent need for a more comprehensive, integrated approach to estimate the global impacts of food trade on the environment. Second, research is needed to improve the evaluation of some key aspects of the relative value of each resource depending on the local and regional biophysical and socio–economic context. Finally, to enhance the impact of such evaluations and their applicability in decision-making, scenario analyses and accounting of key issues like deforestation and groundwater exhaustion will be required. (letter)

Environmental impacts of food trade via resource use and greenhouse gas emissions

Science.gov (United States)

Dalin, Carole; Rodríguez-Iturbe, Ignacio

2016-03-01

Agriculture will need to significantly intensify in the next decades to continue providing essential nutritive food to a growing global population. However, it can have harmful environmental impacts, due to the use of natural and synthetic resources and the emission of greenhouse gases, which alter the water, carbon and nitrogen cycles, and threaten the fertility, health and biodiversity of landscapes. Because of the spatial heterogeneity of resource productivity, farming practices, climate, and land and water availability, the environmental impact of producing food is highly dependent on its origin. For this reason, food trade can either increase or reduce the overall environmental impacts of agriculture, depending on whether or not the impact is greater in the exporting region. Here, we review current scientific understanding of the environmental impacts of food trade, focusing on water and land use, pollution and greenhouse gas emissions. In the case of water, these impacts are mainly beneficial. However, in the cases of pollution and greenhouse gas emissions, this conclusion is not as clear. Overall, there is an urgent need for a more comprehensive, integrated approach to estimate the global impacts of food trade on the environment. Second, research is needed to improve the evaluation of some key aspects of the relative value of each resource depending on the local and regional biophysical and socio-economic context. Finally, to enhance the impact of such evaluations and their applicability in decision-making, scenario analyses and accounting of key issues like deforestation and groundwater exhaustion will be required.

Research on impacts of population-related factors on carbon emissions in Beijing from 1984 to 2012

International Nuclear Information System (INIS)

Yang, Yayun; Zhao, Tao; Wang, Yanan; Shi, Zhaohui

2015-01-01

Carbon emissions related to population factors have aroused great attention around the world. A multitude of literature mainly focused on single demographic impacts on environmental issues at the national level, and comprehensive studies concerning population-related factors at a city level are rare. This paper employed STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model incorporating PLS (Partial least squares) regression method to examine the influence of population-related factors on carbon emissions in Beijing from 1984 to 2012. Empirically results manifest that urbanization is the paramount driver. Changes in population age structure have significantly positive impacts on carbon emissions, and shrinking young population, continuous expansion of working age population and aging population will keep on increasing environmental pressures. Meanwhile, shrinking household size and expanding floating population boost the discharge of carbon emissions. Besides, per capita consumption is an important contributor of carbon emissions, while industry energy intensity is the main inhibitory factor. Based upon these findings and the specific circumstances of Beijing, policies such as promoting clean and renewable energy, improving population quality and advocating low carbon lifestyles should be enhanced to achieve targeted emissions reductions. - Highlights: • We employed the STIRPAT model to identify population-related factors of carbon emissions in Beijing. • Urbanization is the paramount driver of carbon emissions. • Changes in population age structure exert significantly positive impacts on carbon emissions. • Shrinking household size, expanding floating population and improving consumption level increase carbon emissions. • Industry energy intensity decreases carbon emissions

Research on impacts of population-related factors on carbon emissions in Beijing from 1984 to 2012

Energy Technology Data Exchange (ETDEWEB)

Yang, Yayun; Zhao, Tao; Wang, Yanan, E-mail: wyn3615@126.com; Shi, Zhaohui

2015-11-15

Carbon emissions related to population factors have aroused great attention around the world. A multitude of literature mainly focused on single demographic impacts on environmental issues at the national level, and comprehensive studies concerning population-related factors at a city level are rare. This paper employed STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model incorporating PLS (Partial least squares) regression method to examine the influence of population-related factors on carbon emissions in Beijing from 1984 to 2012. Empirically results manifest that urbanization is the paramount driver. Changes in population age structure have significantly positive impacts on carbon emissions, and shrinking young population, continuous expansion of working age population and aging population will keep on increasing environmental pressures. Meanwhile, shrinking household size and expanding floating population boost the discharge of carbon emissions. Besides, per capita consumption is an important contributor of carbon emissions, while industry energy intensity is the main inhibitory factor. Based upon these findings and the specific circumstances of Beijing, policies such as promoting clean and renewable energy, improving population quality and advocating low carbon lifestyles should be enhanced to achieve targeted emissions reductions. - Highlights: • We employed the STIRPAT model to identify population-related factors of carbon emissions in Beijing. • Urbanization is the paramount driver of carbon emissions. • Changes in population age structure exert significantly positive impacts on carbon emissions. • Shrinking household size, expanding floating population and improving consumption level increase carbon emissions. • Industry energy intensity decreases carbon emissions.

Concours annuels Academie Royale des Sciences d'Outre-mer

Directory of Open Access Journals (Sweden)

Royal Academy for Overseas Sciences

2011-01-01

Full Text Available Yearly competitions Royal Academy for Overseas Sciences. L'Organisation des Nations Unies, face aux inégalités croissantes a initié le processus des Objectifs du Millénaire pour le Développement (OMD qui doivent être réalisés d'ici 2015. L'atteinte des huit OMD devrait permettre de réduire la pauvreté et d'améliorer les conditions de vie des populations. L'élevage est pratiqué par une grande partie de la population mondiale surtout les plus pauvres. Il est pourvoyeur d'emplois et contribue à l'émancipation des femmes grâce aux revenus générés par la vente des produits animaux. Les animaux d'élevage sont également utilisés pour le transport et la culture attelée. La forte densité en nutriments des produits animaux en fait des aliments de choix pour améliorer l'état nutritionnel des enfants. La domestication des espèces animales sauvages et le développement de l'aquaculture contribuent à réduire les prélèvements dans la nature et à protéger la biodiversité. Le développement d'un élevage durable et raisonné peut donc positivement impacter plusieurs secteurs et doper la croissance économique des pays. Ce qui peut aider les pays en développement à se rapprocher des OMD d'ici 2015. La note présente également les pré-requis pour rendre effective la contribution de l'élevage aux.

Study of secondary electronic emission in some piezo-electric materials: application to ultrasonic visualization; Etude de l'emission electronique secondaire de quelques materiaux piezoelectriques: application a la visualisation ultrasonore

Energy Technology Data Exchange (ETDEWEB)

Marini, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

Methods allowing the visualization of acoustic images appear at the moment to be of great interest in the field of non-destructive testing as well as in that of underwater detection. In order to carry out certain calculations on the operation of an ultrasonic camera, it has been necessary to study the secondary electron emission of some piezoelectric materials liable to be incorporated into the equipment. The secondary electron emission of insulators is a rather complex phenomenon; in order to find a rational explanation for the observations made, a theory has been developed for the energy spectrum of the emitted electrons. The experimental results of this work have then been used to build an ultrasonic visualization installation. Some examples of acoustic images which have been visualized are also presented. (author) [French] Les methodes qui permettent de visualiser des images acoustiques trouvent a l'heure actuelle un grand interet dans le domaine du controle non destructif comme dans celui de la detection sous-marine. De maniere a effectuer certains calculs sur le fonctionnement d'une camera ultrasons, il a ete necessaire d'etudier l'emission electronique secondaire de quelques materiaux piezoelectriques susceptibles d'etre utilises dans sa construction. L'emission electronique secondaire des isolants est un phenomene assez complexe et de maniere a trouver des explications coherentes aux observations effectuees, une theorie du spectre energetique des electrons emis a ete elaboree. Une installation de visualisation ultrasonore a alors ete realisee a partir des donnees experimentales de cette etude. Quelques exemples d'images acoustiques visualisees par cette methode sont egalement presentees. (auteur)

Review of avoidance reactions of tropical fish to a survey vessel = Revue des réactions d'évitement des poissons tropicaux au passage d'un navire de prospection

OpenAIRE

Gerlotto, François; Fréon, Pierre

1990-01-01

Les réactions des poissons pélagiques tropicaux au passage d'un navire de recherches sont décrites en fonction de l'impact qu'elles peuvent avoir sur les résultats des prospections acoustiques. Deux composantes principales sont décrites : déplacement du poisson latéralement ou en plongée, et situation dans les trois dimensions. Une description empirique des influences des divers stimuli d'un navire sur les poissons est proposée : les trois stimuli pris en compte sont le bruit, l'éclairement d...

Controlling spontaneous emission dynamics in semiconductor micro cavities

Science.gov (United States)

Gayral, B.

Spontaneous emission of light can be controlled, cavity quantum electrodynamics tells us, and many experiments in atomic physics demonstrated this fact. In particular, coupling an emitter to a resonant photon mode of a cavity can enhance its spontaneous emission rate: this is the so-called Purcell effect. Though appealing it might seem to implement these concepts for the benefit of light-emitting semiconductor devices, great care has to be taken as to which emitter/cavity system should be used. Semiconductor quantum boxes prove to be good candidates for witnessing the Purcell effect. Also, low volume cavities having a high optical quality in other words a long photon storage time are required. State-of-the-art fabrication techniques of such cavities are presented and discussed.We demonstrate spontaneous emission rate enhancement for InAs/GaAs quantum boxes in time-resolved and continuous-wave photoluminescence experiments. This is done for two kinds of cavities, namely GaAs/AlAs micropillars (global enhancement by a factor of 5), and GaAs microdisks (global enhancement by a factor of 20). Prospects for lasers, light-emitting diodes and single photon sources based on the Purcell effect are discussed. L'émission spontanée de lumière peut être contrôlée, ainsi que nous l'enseigne l'électrodynamique quantique en cavité, ce fait a été démontré expérimentalement en physique atomique. En particulier, coupler un émetteur à un mode photonique résonnant d'une cavité peut exalter son taux d'émission spontanée : c'est l'effet Purcell. Bien qu'il semble très prometteur de mettre en pratique ces concepts pour améliorer les dispositifs semi-conducteurs émetteurs de lumière, le choix du système émetteur/cavité est crucial. Nous montrons que les boîtes quantiques semi-conductrices sont des bons candidats pour observer l'effet Purcell. Il faut par ailleurs des cavités de faible volume ayant une grande qualité optique en d'autres mots un long temps de

La gestion des résultats des entreprises innovantes

OpenAIRE

Dumas, Guillaume

2014-01-01

Cette thèse s’intéresse à la gestion des résultats dans le cadre des entreprises innovantes. Elle est constituée de trois articles. Dans le premier, il s’agit d’examiner si les résultats des entreprises innovantes sont gérés et si le stade de développement des innovations influence cette gestion des résultats. Il apparaît que les résultats des entreprises innovantes sont gérés à la hausse. Cette gestion ne semble intervenir qu’au cours de l’activité d’innovation (c’est-à-dire lorsque les entr...

Etude des erreurs d'estimation des populations par la méthode des captures successives (DeLURY, 2 captures et des captures-recaptures (PETERSEN

Directory of Open Access Journals (Sweden)

LAURENT M.

1978-01-01

Full Text Available L'estimation des populations naturelles par capture-recapture et par captures successives est souvent entachée d'erreur car, dans de nombreux cas, l'hypothèse fondamentale d'égalité des probabilités de captures pour tous les individus dans le temps et dans l'espace n'est pas respectée. Dans le cas des populations de poissons envisagés ici, les captures ont lieu par la pêche électrique. On a pu chiffrer l'ordre de grandeur des erreurs systématiques faites sur l'estimation des peuplements, en fonction des conditions particulières, biotiques et abiotiques, des différents milieux inventoriés.

Environmental impact of coal mine methane emissions and responding strategies in China

Energy Technology Data Exchange (ETDEWEB)

Cheng, Y.P.; Wang, L.; Zhang, X.L. [China University of Mining & Technology, Xuzhou (China)

2011-01-15

The impact on global climate change from coal mine methane emissions in China has been drawing attention as coal production has powered its economic development. Data on coal mine methane emissions from the State Administration of Coal Mine Safety of China has been analyzed. It is estimated that the methane emission from coal mining in China reached 20 billions of cubic meters in 2008, most of which comes from state-owned coal mines with high-gas content. China releases six times as much of methane from coal mines as compared to the United States. However, Chinese methane emission from coal production accounts for only a very small proportion on the environmental impact when compared to emissions of carbon dioxide from fossil fuel consumption. The Chinese government has shown environmental awareness and resolution on the mitigation and utilization of coal mine methane emissions. Measures have been taken to implement the programs of mitigation and utilization of coal mine methane, and at the same time, to ensure mining safety. Nearly 7.2 billions of cubic meters of methane were drained from the coal mines, and 32% of it was utilized in 2008. The slow advancement of technologies for the drainage and utilization of low-concentration methane from ventilation air hinders the progress of mitigation of atmospheric methane and the utilization of coal mine methane emissions.

impacts des rejets industriels sur les eaux souterraines

African Journals Online (AJOL)

USER

pollution et sont nombreuses, notamment les usines sidérurgiques, métalliques et pétrochimiques. Leurs rejets ont des effets néfastes sur les eaux de la région. Actuellement, les effluents industriels situés dans la région de Berrahal, contiennent d'importantes quantités de produits chimiques organiques et inorganiques et ...

Étude du vieillissement des batteries lithium-ion dans les applications "véhicule électrique" : Combinaison des effets de vieillissement calendaire et de cyclage.

OpenAIRE

REDONDO-IGLESIAS, Eduardo

2017-01-01

L'étude du vieillissement des batteries est nécessaire car la dégradation de leurs caractéristiques détermine en grande partie le coût, les performances et l'impact environnemental des véhicules électrifiés, notamment des véhicules 100 % électriques. La méthodologie choisie pour cette thèse consiste en deux étapes bien différenciées, à savoir la caractérisation et la modélisation. Pour la première étape, on s'appuie sur des essais de vieillissement accéléré d'éléments de batterie. Malgré leur...

Isotope analysis by emission spectroscopy; Analyse isotopique par spectroscopie d'emission

Energy Technology Data Exchange (ETDEWEB)

Artaud, J; Gerstenkorn, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Blaise, J [Centre National de la Recherche Scientifique (CNRS), Lab. Aime Cotton, 92 - Meudon-Bellevue (France)

1959-07-01

Quantitative analysis of isotope mixtures by emission spectroscopy is resulting from the phenomenon called 'isotope shift', say from the fact that spectral lines produced by a mixture of isotopes of a same element are complex. Every spectral line is, indeed, resulting from several lines respectively corresponding to each isotope. Then isotopic components are near one to others, and their separation is effected by means of Fabry-Perot calibration standard: the apparatus allowing to measure abundances is the Fabry-Perot photo-electric spectrometer, designed in 1948 by MM. JACQUINOT and DUFOUR. This method has been used to make abundance determination in the case of helium, lithium, lead and uranium. In the case of lithium, the utilised analysis line depends on the composition of examined isotopic mixture. For mixtures containing 7 to 93 pour cent of one of isotopes of lithium, this line is the lithium blue line: {lambda} = 4603 angstrom. In other cases the red line {lambda} = 6707 angstrom is preferable, though it allows to do easily nothing but relative determinations. Helium shows no particular difficulty and the analysis line selected was {lambda} = 6678 angstrom. For lead the line {lambda} = 5201 angstrom gives the possibility to determine the isotope abundance for the four isotopes of lead notwithstanding the presence of hyperfine structure of {sup 207}Pb. For uranium, line {lambda} 5027 angstrom is used, and this method allows to determine the composition of isotope mixtures, the content of which in {sup 235}U may shorten to 0,1 per cent. Relative precision is about 2 per cent for contents in {sup 235}U over 1 per cent. For lower contents, this line {lambda} = 5027 angstrom will allow relative measures when using previously dosed mixtures. (author) [French] L'analyse quantitative des melanges isotopiques par spectroscopie d'emission doit son existence au phenomene appele 'deplacement isotopique', c'est-a-dire au fait que les raies spectrales emises par un

Anisotropies of the neutron emission of the 'Focus' discharge compared with different theoretical models; Anisotropies de l'emission neutronique de la decharge 'Focus' comparees a divers modeles theoriques

Energy Technology Data Exchange (ETDEWEB)

Patou, Claude; Simonnet, Alain

1969-08-06

When a plasma emits enough neutrons to make an analysis of this neutrons possible, the study of emission characteristics allows the mechanism governing fusion reaction to be specified. The experimental study of neutron flow and energy anisotropies is herein compared with various possible theoretical models. It seems that the 'Boiler' model (thermal plasma in movement) matches the obtained results. Only observed flow values in the discharge axis remain unexplained. Although the study approach does not allow to be sure of plasma thermalization in the strict meaning of the term, it seems that there is a relatively well established anisotropy of the speed distribution function of reacting ions [French] Lorsqu'un plasma emet suffisamment de neutrons pour les soumettre a l'analyse, l'etude des caracteristiques de l'emission permet de preciser le mecanisme responsable des reactions de fusion. L'etude experimentale des anisotropies du flux et de l'energie des neutrons est comparee a divers modeles theoriques possibles. Il semble que le modele du 'Boiler' - plasma thermique en mouvement - s'accorde avec nos resultats. Seules les valeurs des flux observes selon l'axe de la decharge restent sans explication. Bien que ce moyen d'etude ne permette pas d'etre certain de la thermalisation du plasma au sens strict du terme, il semble cependant qu'on se trouve en presence d'une isotropie relativement bien realisee de la fonction de distribution des vitesses des ions qui entrent en reaction. (auteurs)

Measurement of the dead time of a G.M. counter and of the secondary emission of the cathode by the method of the delayed coincidences; Mesure du temps mort d'un compteur G.M. et de l'emission secondaire de la cathode par la methode des coincidences retardees

Energy Technology Data Exchange (ETDEWEB)

Picard, E; Rogozinski, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1953-07-01

The dead time of a G.M counter is measured with the method of delayed coincidences. The pulses of the counter that supplies the circuit of coincidences, arrive there, on the one hand, directly, and in the other part, after a known and variable delay. This method permits besides, to study the parasitic impulses coming from the impact of the positive ions on the cathode of the meter. From the results relative to several counters working in various conditions are given. (author) [French] Le temps mort d'un compteur G.M. est mesure a l'aide d'un methode de coincidences retardees. Les impulsions du compteur qui alimentent le circuit de coincidences, y parviennent, d'une part, directement, et, dautre part, apres un retard connu et variable. Cette methode permet de plus, d'etudier les impulsions parasites provenant de l'impact des ions positifs sur la cathode du compteur. Des resultats relatifs a plusieurs compteurs fonctionnant dans des conditions diverses sont donnes. (auteur)

Optical Engines as Representative Tools in the Development of New Combustion Engine Concepts Moteurs transparents comme outils représentatifs dans le développement de nouveaux concepts des moteurs à combustion interne

Directory of Open Access Journals (Sweden)

Kashdan J.

2011-11-01

Full Text Available Single cylinder optical engines are used for Internal Combustion (IC engine research as they allow for the application of qualitative and quantitative non-intrusive, diagnostic techniques to study in-cylinder flow, mixing, combustion and emissions phenomena. Such experimental data is not only important for the validation of computational models but can also provide a detailed insight into the physical processes occurring in-cylinder which is useful for the further development of new combustion strategies such as gasoline Homogeneous Charge Compression Ignition (HCCI and Diesel Low Temperature Combustion (LTC. In this context, it is therefore important to ensure that the performance of optical engines is comparable to standard all-metal engines. A comparison of optical and all-metal engine combustion and emissions performance was performed within the present study. The objective was to investigate the principal differences between optical and all-metal engines and understand how these differences ultimately affect mixing, combustion and emissions formation processes. Experimental results reveal the significant impact of differences in combustion chamber wall temperatures between optical and standard engine piston bowls on combustion phasing and engine-out emissions. Quantitative measurements of piston wall temperatures using a laser-induced phosphorescence technique were performed which allowed the subsequent definition of appropriate engine operating strategies so as to compensate for differences in heat transfer properties. Furthermore, differences in combustion chamber geometry were also studied. Geometrical differences can arise as a result of dynamic (compressive/tensile and thermal loading of the extended piston-liner assembly on the optical engine, potentially leading to changes in the effective Compression Ratio. In addition, intake charge dilution in optical engines is often achieved via the use of simulated Exhaust Gas Recirculation

The impacts of weather variations on energy demand and carbon emissions

International Nuclear Information System (INIS)

Considine, T.J.

2000-01-01

This paper examines the impacts of climate fluctuations on carbon emissions using monthly models of US energy demand. The econometric analysis estimates price, income, and weather elasticities of short-run energy demand. Our model simulations suggest that warmer climate conditions in the US since 1982 slightly reduced carbon emissions in the US. Lower energy use associated with reduced heating requirements offsets higher fuel consumption to meet increased air-conditioning needs. The analysis also suggests that climate change policies should allow some variance in carbon emissions due to short-term weather variations

Impact environnemental d'une désulfuration poussée des gazoles Environmental Impact of Gaz Oil Desulfurization

Directory of Open Access Journals (Sweden)

Armengol C.

2006-11-01

Full Text Available En une dizaine d'années, le diesel a connu un développement spectaculaire sur les marchés automobile français et européen et pourrait atteindre, en 1995, la moitié des immatriculations de véhicules particuliers en France et le quart en Europe de l'Ouest. Cette situation n'est évidemment pas sans poser de problèmes. Problèmes environnementaux puisque le moteur diesel est une source plus importante d'émissions d'oxydes d'azote et de particules que le convertisseur essence, mais également au niveau de l'industrie du raffinage qui, en France, n'est plus en mesure de satisfaire la demande en gazole. De plus, à compter du 1er octobre 1996, la teneur en soufre du gazole routier ne devra pas excéder 0,05 %, conformément aux nouvelles spécifications européennes. Cette perspective de production de carburants fortement désulfurés va affecter directement l'équilibre en hydrogène de la raffinerie et donc les autoconsommations et les émissions de CO2. L'objectif de cette étude est de mesurer l'impact sur l'environnement d'une réduction de la teneur en soufre des gazoles de 0,3 à 0,05 %. Le bilan est réalisé sur l'ensemble de la filière énergétique, depuis l'extraction du pétrole jusqu'à la combustion du carburant dans le moteur. Les gains et les pertes en termes de pollution locale ou globale sont évalués suivant la nature de l'hydrogène utilisé (oxydation partielle de résidus sous vide ou de charbon, reformage à la vapeur de gaz naturel ou de naphta électrolyse et la nature de la charge à traiter (gazole straight run ou light cycle oil lors de l'hydrodésulfuration. Over the past decade, diesel had made large advances in the French and European automobile markets. In 1995, diesel could account for half of all private vehicle registrations in France, and a quarter in Western Europe. This situation inevitably raises a number of problems : environmental problems, because the diesel engine emits more nitrogen oxides and

Injectabilite des coulis de ciment dans des milieux fissures

Science.gov (United States)

Mnif, Thameur

Le travail presente ici est un bilan du travaux de recherche effectues sur l'injectabilite des coulis de ciment dans lu milieux fissures. Un certain nombre de coulis a base de ciment Portland et microfin ont ete selectionnes afin de caracteriser leur capacite a penetrer des milieux fissures. Une partie des essais a ete menee en laboratoire. L'etude rheologique des differents melanges a permis de tester l'influence de l'ajout de superplastifiant et/ou de fumee de silice sur la distribution granulometrique des coulis et par consequent sur leur capacite a injecter des colonnes de sable simulant un milieu fissure donne. La classe granulometrique d'un coulis, sa stabilite et sa fluidite sont apparus comme les trois facteurs principaux pour la reussite d'une injection. Un facteur de finesse a ete defini au cours de cette etude: base sur la classe granulometrique du ciment et sa stabilite, il peut entrer dans la formulation theorique du debit d'injection avant application sur chantier. La deuxieme et derniere partie de l'etude presente les resultats de deux projets de recherche sur l'injection realises sur chantier. L'injection de dalles de beton fissurees a permis le suivi de l'evolution des pressions avec la distance au point d'injection. L'injection de murs de maconnerie a caractere historique a montre l'importance de la definition de criteres de performance des coulis a utiliser pour traiter un milieu donne et pour un objectif donne. Plusieurs melanges peuvent ainsi etre predefinis et mis a disposition sur le chantier. La complementarite des ciments traditionnels et des ciments microfins devient alors un atout important. Le choix d'utilisation de ces melanges est fonction du terrain rencontre. En conclusion, cette recherche etablit une methodologie pour la selection des coulis a base de ciment et des pressions d'injection en fonction de l'ouverture des fissures ou joints de construction.

How accounting for climate and health impacts of emissions could change the US energy system

International Nuclear Information System (INIS)

Brown, Kristen E.; Henze, Daven K.; Milford, Jana B.

2017-01-01

This study aims to determine how incorporating damages into energy costs would impact the US energy system. Damages from health impacting pollutants (NO_x, SO_2, particulate matter - PM, and volatile organic compounds - VOCs) as well as greenhouse gases (GHGs) are accounted for by applying emissions fees equal to estimated external damages associated with life-cycle emissions. We determine that in a least-cost framework, fees reduce emissions, including those not targeted by the fees. Emissions reductions are achieved through the use of control technologies, energy efficiency, and shifting of fuels and technologies used in energy conversion. The emissions targeted by fees decrease, and larger fees lead to larger reductions. Compared to the base case with no fees, in 2045, SO_2 emissions are reduced up to 70%, NO_x emissions up to 30%, PM_2_._5 up to 45%, and CO_2 by as much as 36%. Emissions of some pollutants, particularly VOCs and methane, sometimes increase when fees are applied. The co-benefit of reduction in non-targeted pollutants is not always larger for larger fees. The degree of co-reduced emissions depends on treatment of life-cycle emissions and the technology pathway used to achieve emissions reductions, including the mix of efficiency, fuel switching, and emissions control technologies. - Highlights: • Fees based on damages related to energy use are modeled on the US energy system. • Health impacting air pollutants and greenhouse gases are targeted by fees. • Both targeted and other pollutants are reduced compared to a system without fees. • Control technologies, energy efficiency, and shifts in fuels reduce emissions. • Co-benefits do not necessarily increase as fees increase.

La gouvernance des risques naturels et la problematique des ...

African Journals Online (AJOL)

Depuis quelques années, la gouvernance des risques naturels dus aux inondations remet en cause les processus de mise en oeuvre des politiques urbaines et la qualité de la structure des aménagements dans les grandes villes du Golfe de Guinée. La perception de la gouvernance et l'application des politiques de ...

Impact of population and economic growth on carbon emissions in Taiwan using an analytic tool STIRPAT

Directory of Open Access Journals (Sweden)

Jong-Chao Yeh

2017-01-01

Full Text Available Carbon emission has increasingly become an issue of global concern because of climate change. Unfortunately, Taiwan was listed as top 20 countries of carbon emission in 2014. In order to provide appropriate measures to control carbon emission, it appears that there is an urgent need to address how such factors as population and economic growth impact the emission of carbon dioxide in any developing countries. In addition to total population, both the percentages of population living in urban area (i.e., urbanization percentage, and non-dependent population may also serve as limiting factors. On the other hand, the total energy-driven gross domestic production (GDP and the percentage of GDP generated by the manufacturing industries are assessed to see their respective degree of impact on carbon emission. Therefore, based on the past national data in the period 1990–2014 in Taiwan, an analytic tool of Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT was employed to see how well those aforementioned factors can describe their individual potential impact on global warming, which is measured by the total amount of carbon emission into the atmosphere. Seven scenarios of STIRPAT model were proposed and tested statistically for the significance of each proposed model. As a result, two models were suggested to predict the impact of carbon emission due to population and economic growth by the year 2025 in Taiwan.

Characterization of the emissions impacts of hybrid excavators with a portable emissions measurement system (PEMS)-based methodology.

Science.gov (United States)

Cao, Tanfeng; Russell, Robert L; Durbin, Thomas D; Cocker, David R; Burnette, Andrew; Calavita, Joseph; Maldonado, Hector; Johnson, Kent C

2018-04-13

Hybrid engine technology is a potentially important strategy for reduction of tailpipe greenhouse gas (GHG) emissions and other pollutants that is now being implemented for off-road construction equipment. The goal of this study was to evaluate the emissions and fuel consumption impacts of electric-hybrid excavators using a Portable Emissions Measurement System (PEMS)-based methodology. In this study, three hybrid and four conventional excavators were studied for both real world activity patterns and tailpipe emissions. Activity data was obtained using engine control module (ECM) and global positioning system (GPS) logged data, coupled with interviews, historical records, and video. This activity data was used to develop a test cycle with seven modes representing different types of excavator work. Emissions data were collected over this test cycle using a PEMS. The results indicated the HB215 hybrid excavator provided a significant reduction in tailpipe carbon dioxide (CO 2 ) emissions (from -13 to -26%), but increased diesel particulate matter (PM) (+26 to +27%) when compared to a similar model conventional excavator over the same duty cycle. Copyright © 2018 Elsevier B.V. All rights reserved.

Impacts of urban form on future US passenger-vehicle greenhouse gas emissions

Energy Technology Data Exchange (ETDEWEB)

Hankey, Steve; Marshall, Julian D. [Department of Civil Engineering, University of Minnesota, 500 Pillsbury Drive SE, Minneapolis, MN 55455 (United States)

2010-09-15

Urban form - for example, sprawl versus infill development - impacts people's daily travel patterns and annual vehicle-kilometers traveled (VKT). This paper explores how urban form impacts greenhouse gas (GHG) emissions from passenger-vehicles, the largest source of urban transportation GHG emissions. Our research uses a recently published urban scaling rule to develop six scenarios for high- and low-sprawl US urban growth. We develop and apply a Monte Carlo approach that describes ensemble statistics for several dozen urban areas rather than forecasting changes in individual urban areas. Then, employing three vehicle- and fuel-technology scenarios, we estimate total passenger VKT and resulting GHG emissions for US urban areas. Our results indicate that comprehensive compact development could reduce US 2000-2020 cumulative emissions by up to 3.2 GtCO{sub 2}e (15-20% of projected cumulative emissions). In general, vehicle GHG mitigation may involve three types of approaches: more-efficient vehicles, lower-GHG fuels, and reduced VKT. Our analyses suggest that all three categories must be evaluated; otherwise, improvements in one or two areas (e.g., vehicle fuel economy, fuel carbon content) can be offset by backsliding in a third area (e.g., VKT growth). (author)

Impacts of urban form on future US passenger-vehicle greenhouse gas emissions

International Nuclear Information System (INIS)

Hankey, Steve; Marshall, Julian D.

2010-01-01

Urban form - for example, sprawl versus infill development - impacts people's daily travel patterns and annual vehicle-kilometers traveled (VKT). This paper explores how urban form impacts greenhouse gas (GHG) emissions from passenger-vehicles, the largest source of urban transportation GHG emissions. Our research uses a recently published urban scaling rule to develop six scenarios for high- and low-sprawl US urban growth. We develop and apply a Monte Carlo approach that describes ensemble statistics for several dozen urban areas rather than forecasting changes in individual urban areas. Then, employing three vehicle- and fuel-technology scenarios, we estimate total passenger VKT and resulting GHG emissions for US urban areas. Our results indicate that comprehensive compact development could reduce US 2000-2020 cumulative emissions by up to 3.2 GtCO 2 e (15-20% of projected cumulative emissions). In general, vehicle GHG mitigation may involve three types of approaches: more-efficient vehicles, lower-GHG fuels, and reduced VKT. Our analyses suggest that all three categories must be evaluated; otherwise, improvements in one or two areas (e.g., vehicle fuel economy, fuel carbon content) can be offset by backsliding in a third area (e.g., VKT growth).

Trade pattern change impact on industrial CO2 emissions in Taiwan

International Nuclear Information System (INIS)

Wu, Jung-Hua; Huang, Yun-Hsun; Chen, Yen-Yin

2007-01-01

Input-output structural decomposition analysis (I-O SDA) is applied in this paper to analyze the sources of change in industrial CO 2 emissions in Taiwan from 1989 to 2001. Owing to the fact that Taiwan is an export-oriented, trade-dependent economy, the focus is on trade transformation over the past decade and its effect over industrial CO 2 emissions. Change in trade patterns has significantly impacted many aspects of the Taiwan economy, subsequently resulting in various influences on industrial CO 2 emissions, as shown by empirical analysis results. Change in export level increased industrial CO 2 emissions, above all other effects, by 72.1%. However, changes in export mix and import coefficients imposed effects of dragging down industrial CO 2 emissions by 5.7% and 11.7%, respectively. (author)

Impact of SO2 emissions cap on Phase I compliance decisions

International Nuclear Information System (INIS)

Bissell, P.E.; Fink, C.E.; Koch, B.J.; Chomka, P.A.

1990-01-01

The SO 2 emissions cap provisions of impending clean air legislation will dramatically affect Phase I and Phase II compliance decisions by electric utilities. Technology-based SO 2 reduction alternatives could become the keystone of most compliance strategies as utilities attempt to achieve lower and lower SO 2 emission rates. Compliance with the Phase II emissions cap will require technological solutions for many utilities which must meet system-wide SO 2 emission rates well below those achievable with low-sulfur eastern coals and, in many instances, western coals. The emissions cap provision, however, will also induce more scrubbing during the Phase I compliance period. The power generation dispatch capability of a hypothetical utility system was simulated to study the impacts of an SO 2 emission cap on compliance strategies in Phase I. The effects of the cap were quantified for generation costs, total SO 2 emissions, and effective emission rates. The results show that achieving compliance by installing state-of-the-art high SO 2 removal scrubbers becomes increasingly attractive as utilities become constrained under the SO 2 cap, even in Phase I

Le rôle des intervenants non gouvernementaux dans le ...

International Development Research Centre (IDRC) Digital Library (Canada)

Ce projet servira à déterminer les facteurs stratégiques et réglementaires qui ont contribué ou nui aux efforts visant à permettre aux fournisseurs non gouvernementaux de participer au renforcement des systèmes de santé. Le rôle des fournisseurs de ... Climate Change and Water Adaptation Options. The impacts of climate ...

Contribution to the study of influences in emission spectrography on solutions. Application to a general analysis method for stainless steels (1961); Contribution a l'etude des influences en spectographie d'emission sur solution. Application a une methode generale d'analyse des aciers inoxydables (1961)

Energy Technology Data Exchange (ETDEWEB)

Baudin, G [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1961-11-15

In order to establish a general method of analysis of stainless steels, by means of spark spectroscopy on solutions, a systematic study has been made of the factors involved. The variations in acidity of the solutions, or in the ratio of concentrations of two acids at constant pH, lead to a displacement of the calibration curve. Simple relations have been established between the concentration of the extraneous elements, and the effects produced, for the constituents Fe, Ti, Ni, Cr, Mn; a general method using abacus is proposed for steels containing only these elements. The interactions in the case of the elements Mo, Nb, Ta, W, were more complex, so that the simultaneous separation was studied with the help of ion-exchange resins. A general method of analysis is proposed for stainless steels. (author) [French] En vue d'etablir une methode generale d'analyse des aciers inoxydables par spectrographie d'etincelles sur solution, on a effectue une etude systematique des influences. Les variations de l'acidite des solutions ou du rapport des concentrations de deux acides a pH constant, entrainent un deplacement des courbes d'etalonnage. On a etabli des relations simples entre la teneur des tiers elements et les effets produits pour les constituants Fe, Ti, Ni, Cr, Mn; une methode generale avec abaques est proposee pour les aciers contenant ces seuls elements. Les influences dans le cas des elements Mo, Nb, Ta, W etant plus complexes, on eut a etudier la separation simultanee a l'aide de resines echangeuses d'ions. On propose une methode generale d'analyse des aciers inoxydables. (auteur)

The Impact of Patient Education on Diabetes Empowerment Scale (DES) and Diabetes Attitude Scale (DAS-3) in Patients with Type 2 Diabetes

OpenAIRE

ATAK, Nazlı; KÖSE, Kenan; GÜRKAN, Tanju

2008-01-01

Aim: This study was conducted to assess the impact of a brief, patient-centered education program on perceived self-efficacy and attitudes towards diabetes of patients with type 2 diabetes. Materials and Methods: A randomized controlled study was designed and conducted to assess the impact of education using the DES (Diabetes Empowerment Scale) and DAS-3 (Diabetes Attitude Questionnaire-3), which were administered using a pre- and post-test design. A patient-centered education program was d...

Impacts of biogenic emissions of VOC and NOx on tropospheric ozone during summertime in eastern China.

Science.gov (United States)

Wang, Qin'geng; Han, Zhiwei; Wang, Tijian; Zhang, Renjian

2008-05-20

This study is intended to understand and quantify the impacts of biogenic emissions of volatile organic compounds (VOC) and nitrogen oxides (NO(x)) on the formation of tropospheric ozone during summertime in eastern China. The model system consists of the non-hydrostatic mesoscale meteorological model (MM5) and a tropospheric chemical and transport model (TCTM) with the updated carbon-bond chemical reaction mechanism (CBM-IV). The spatial resolution of the system domain is 30 km x 30 km. The impacts of biogenic emissions are investigated by performing simulations (36 h) with and without biogenic emissions, while anthropogenic emissions are constant. The results indicate that biogenic emissions have remarkable impacts on surface ozone in eastern China. In big cities and their surrounding areas, surface ozone formation tends to be VOC-limited. The increase in ozone concentration by biogenic VOC is generally 5 ppbv or less, but could be more than 10 ppbv or even 30 ppbv in some local places. The impacts of biogenic NO(x) are different or even contrary in different regions, depending on the relative availability of NO(x) and VOC. The surface ozone concentrations reduced or increased by the biogenic NO(x) could be as much as 10 ppbv or 20 ppbv, respectively. The impacts of biogenic emissions on ozone aloft are generally restricted to the boundary layer and generally more obvious during the daytime than during the nighttime. This study is useful for understanding the role of biogenic emissions and for planning strategies for surface ozone abatement in eastern China. Due to limitations of the emission inventories used and the highly non-linear nature of zone formation, however, some uncertainties remain in the results.

Valorisation et Recyclage des Déchets Plastiques dans le Béton

Directory of Open Access Journals (Sweden)

Benimam Samir

2014-04-01

Full Text Available La valorisation des déchets dans le génie civil est un secteur important dans la mesure où les produits que l’on souhaite obtenir ne sont pas soumis à des critères de qualité trop rigoureux. Le recyclage des déchets touche deux impacts très importants à savoir l’impact et l’impact économique. Donc plusieurs pays du monde, différents déchets sont utilisé dans le domaine de la construction et spécialement dans le ciment ou béton comme poudre, fibres ou agrégats. Ce travail s’intéresse à la valorisation d’un déchet qui est nuisible pour l’environnement vu son caractère encombrant et inesthétique il s’agit du déchet plastique. Trois types de déchets plastiques sont ajoutés dans le béton (sous forme de grains et fibres (ondulées et rectilignes. Les propriétés à l’état frais (maniabilité, air occlus et densité et à l’état durci (résistance à la compression, à la traction, retrait et absorption d’eau des différents bétons réalisés sont analysées et comparés par rapport leurs témoins respectifs. D’après les résultats expérimentaux on peut conclure que le renforcement de la matrice cimentaire avec des fibres plastiques ondulées montrent une nette amélioration de la résistance à la traction du béton ainsi qu’une diminution remarquable de sa capacité d’absorption de l’eau lorsqu’on utilise des grains plastiques.

Instruments used to measure or check {alpha}, {beta}, {gamma} activity and neutron emission in the course of processing ore or irradiated fuel; Appareils de mesure ou de controle {alpha}, {beta}, {gamma}, n, des circuits des usines de traitement du minerai ou du combustible irradie

Energy Technology Data Exchange (ETDEWEB)

Blanc, A; Brunet, M; Kermagoret, M; Labeyrie, J; Roux, G; Vasseur, J; Weil, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1959-07-01

One of the methods checking ores in the course of treatment is the rapid quantitative determination of thorium. This measurement is carried out by means of a scintillation instrument which shows the {beta} and {alpha} coincidences of ThC and ThC'. The treatment of irradiated fuel is accompanied by a large number of radioactive checks relative to the performance of the fixation and elution operations of uranium in the ion exchangers, to the concentration of radioactivity of effluent sent from the plant into watercourses. The operations of fixation and elution of the uranium are checked automatically by an instrument which takes a sample of 5 cm{sup 3} of solution, evaporates it and measures its activity every 10 or 20 minutes. Plutonium concentrations are measured: - in the presence of strong {beta} {gamma} activities, by means of rotating cylinder detectors; - in the presence of weak {beta} {gamma} activities, by means of {alpha} detectors scanning a constant level liquid surface; - by means of fission chambers relatively insensitive to {gamma}. Fission product concentrations are measured by chambers, counters or scintillators, according to the amount of {gamma} activity present. Finally, the activity of effluent to be emptied into watercourses is checked by means of a scintillation instrument, which measures the {alpha} activity on the one hand, and on the other hand the {beta} {gamma} activity of residue from a 100 cm{sup 3} sample taken and evaporated in 20 minutes. (author) [French] Parmi les controles relatifs au minerai en cours de traitement, figure le dosage rapide de thorium. Cette mesure est realisee au moyen d'un appareillage a scintillation qui met en evidence la coincidence des emissions {beta} et {alpha} du ThC et du ThC'. Le traitement des combustibles irradies s'accompagne d'un grand nombre de controles radioactifs portant sur le fonctionnement des operations de fixation et d'elution de l'uranium dans les echangeurs d'ions, sur la concentration du

Environmental impacts of genetically modified (GM) crop use 1996–2013: Impacts on pesticide use and carbon emissions

Science.gov (United States)

Brookes, Graham; Barfoot, Peter

2015-01-01

ABSTRACT This paper updates previous assessments of how crop biotechnology has changed the environmental impact of global agriculture. It focuses on the environmental impacts associated with changes in pesticide use and greenhouse gas emissions arising from the use of GM crops since their first widespread commercial use in the mid 1990s. The adoption of GM insect resistant and herbicide tolerant technology has reduced pesticide spraying by 553 million kg (−8.6%) and, as a result, decreased the environmental impact associated with herbicide and insecticide use on these crops (as measured by the indicator the Environmental Impact Quotient (EIQ)) by19.1%. The technology has also facilitated important cuts in fuel use and tillage changes, resulting in a significant reduction in the release of greenhouse gas emissions from the GM cropping area. In 2013, this was equivalent to removing 12.4 million cars from the roads. PMID:25760405

EFFET DES TRAITEMENTS THERMIQUES SUR LA REACTION ENTRE DES COUCHES MINCES DE TITANE ET DES SUBSTRATS EN ACIER

Directory of Open Access Journals (Sweden)

D Slimani

2015-06-01

Full Text Available Des couches minces du titane pur ont été déposées avec la méthode de pulvérisation cathodique sur des substrats en acier, type FF80 K-1 contenants ~1% mass. en carbone. La réaction entre les deux parties du système substrat-couche mince est activée avec des traitements thermiques sous vide dans l’intervalle de températures de 400 à900°Cpendant 30 minutes. Les Spectres de diffraction de rayons x confirment l’inter- diffusion des éléments  chimiques du système résultants la formation et la croissance des nouvelles phases en particulier le carbure binaire TiC ayant des caractéristiques thermomécaniques importantes. L’analyse morphologique des échantillons traités  avec le microscope électronique à balayage (MEB montre l’augmentation du flux de diffusion atomique avec la température de recuit, notamment la diffusion du manganèse et du fer vers la surface libre des échantillons aux températures élevées provoquant la dégradation des propriétés mécaniques des revêtements contrairement au premiers stades d’interaction où on a obtenu des bonnes valeurs de la microdureté.

Bi-Directional Ion Emission from Massive Gold Cluster Impacts on Nanometric Carbon Foils

OpenAIRE

DeBord, J. Daniel; Della-Negra, Serge; Fernandez-Lima, Francisco A.; Verkhoturov, Stanislav V.; Schweikert, Emile A.

2012-01-01

Carbon cluster emission from thin carbon foils (5–40 nm) impacted by individual Aun+q cluster projectiles (95–125 qkeV, n/q = 3–200) reveals features regarding the energy deposition, projectile range, and projectile fate in matter as a function of the projectile characteristics. For the first time, the secondary ion emission from thin foils has been monitored simultaneously in both forward and backward emission directions. The projectile range and depth of emission were examined as a function...

Bi-Directional Ion Emission from Massive Gold Cluster Impacts on Nanometric Carbon Foils.

Science.gov (United States)

Debord, J Daniel; Della-Negra, Serge; Fernandez-Lima, Francisco A; Verkhoturov, Stanislav V; Schweikert, Emile A

2012-04-12

Carbon cluster emission from thin carbon foils (5-40 nm) impacted by individual Au(n) (+q) cluster projectiles (95-125 qkeV, n/q = 3-200) reveals features regarding the energy deposition, projectile range, and projectile fate in matter as a function of the projectile characteristics. For the first time, the secondary ion emission from thin foils has been monitored simultaneously in both forward and backward emission directions. The projectile range and depth of emission were examined as a function of projectile size, energy, and target thickness. A key finding is that the massive cluster impact develops very differently from that of a small polyatomic projectile. The range of the 125 qkeV Au(100q) (+q) (q ≈ 4) projectile is estimated to be 20 nm (well beyond the range of an equal velocity Au(+)) and projectile disintegration occurs at the exit of even a 5 nm thick foil.

Hydraulic Hybrid Propulsion for Heavy Vehicles: Combining the Simulation and Engine-In-the-Loop Techniques to Maximize the Fuel Economy and Emission Benefits Propulsion hybride hydraulique des poids lourds : une approche alliant les techniques de simulation et d’« Engine-In-the-loop » (EIL afin de maximiser les économies de carburant et les avantages en termes d’émissions

Directory of Open Access Journals (Sweden)

Filipi Z.

2009-09-01

Full Text Available The global energy situation, the dependence of the transportation sector on fossil fuels, and a need for a rapid response to the global warming challenge, provide a strong impetus for development of fuel efficient vehicle propulsion. The task is particularly challenging in the case of trucks due to severe weight/size constraints. Hybridization is the only approach offering significant breakthroughs in near and mid-term. In particular, the series configuration decouples the engine from the wheels and allows full flexibility in controlling the engine operation, while the hydraulic energy conversion and storage provides exceptional power density and efficiency. The challenge stems from a relatively low energy density of the hydraulic accumulator. This places particular emphasis on development of the supervisory controller. The conventional wisdom is to operate the engine at the “sweet spot”, but the aggressive pursuit of engine efficiency as the sole objective can lead to frequent and rapid diesel engine transients, thus causing an adverse affect on the soot emissions and driver feel. Therefore, we propose a comprehensive methodology for considering a combined hybrid system fuel-economy and emissions objective. The fuel economy is addressed with the simulation-based approach, while investigating the impact of engine transients on particulate emission relies on the Engine-In-the-loop (EIL capability. The EIL study confirms advantages of a modulated state-of-charge control over the thermostatic approach, and demonstrates the ability of the Series Hydraulic Hybrid to improve the fuel economy of the medium truck by 72%, while reducing the particulate emission by 74% compared to the conventional baseline over the city driving schedule. La situation énergétique mondiale, la dépendance du secteur des transports vis-à-vis des combustibles d’origine fossile et la nécessité d’une réponse rapide face au défi présenté par le r

Promouvoir l'entrepreneuriat inclusif des jeunes et des femmes ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le projet vise à analyser la contribution réelle et potentielle de l'entrepreneuriat inclusif au bien-être des jeunes et des femmes en Côte d'Ivoire, au Burkina Faso et au Kenya. Après un état des lieux de la pratique de l'entrepreneuriat inclusif dans chacun des pays ciblés, l'équipe de recherche étudiera son incidence sur ...

The Impacts of Regulations and Financial Development on the Operations of Supply Chains with Greenhouse Gas Emissions

Science.gov (United States)

Xiao, Zhuang; Tian, Yixiang; Yuan, Zheng

2018-01-01

To establish a micro foundation to understand the impacts of greenhouse gas (GHG) emission regulations and financial development levels on firms’ GHG emissions, we build a two-stage dynamic game model to incorporate GHG emission regulations (in terms of an emission tax) and financial development (represented by the corresponding financing cost) into a two-echelon supply chain. With the subgame perfect equilibrium, we identify the conditions to determine whether an emission regulatory policy and/or financial development can affect GHG emissions in the supply chain. We also reveal the impacts of the strictness of GHG emission regulation, the financial development level, and the unit GHG emission rate on the operations of the supply chain and the corresponding profitability implications. Managerial insights are also discussed. PMID:29470451

Utilisation des données d’insémination artificielle afin d’identifier l’impact d’un évènement abortif dans les élevages de bovins laitiers

OpenAIRE

Bronner , A.; Morignat, E.; Madouasse, Aurélien; Gasqui, Patrick; Gay, E.; Calavas, D.

2015-01-01

Le présent article a pour objectif de discuter de la faisabilité et de l’intérêt que représenterait le suivi d’un indicateur indirect de survenue des avortements élaboré à partir des données d’insémination artificielle, le taux d’avortements précoces, afin d’identifier l’impact d’un évènement abortif, de manière rétrospective ou prospective. Deux études sont présentées pour illustrer le propos, ayant eu pour objet d’estimer, par l’analyse des variations du taux d’avortements précoces, l’impac...

Free-electron laser emission architecture impact on extreme ultraviolet lithography

Science.gov (United States)

Hosler, Erik R.; Wood, Obert R.; Barletta, William A.

2017-10-01

Laser-produced plasma (LPP) EUV sources have demonstrated ˜125 W at customer sites, establishing confidence in EUV lithography (EUVL) as a viable manufacturing technology. However, for extension to the 3-nm technology node and beyond, existing scanner/source technology must enable higher-NA imaging systems (requiring increased resist dose and providing half-field exposures) and/or EUV multipatterning (requiring increased wafer throughput proportional to the number of exposure passes). Both development paths will require a substantial increase in EUV source power to maintain the economic viability of the technology, creating an opportunity for free-electron laser (FEL) EUV sources. FEL-based EUV sources offer an economic, high-power/single-source alternative to LPP EUV sources. Should FELs become the preferred next-generation EUV source, the choice of FEL emission architecture will greatly affect its operational stability and overall capability. A near-term industrialized FEL is expected to utilize one of the following three existing emission architectures: (1) self-amplified spontaneous emission, (2) regenerative amplifier, or (3) self-seeding. Model accelerator parameters are put forward to evaluate the impact of emission architecture on FEL output. Then, variations in the parameter space are applied to assess the potential impact to lithography operations, thereby establishing component sensitivity. The operating range of various accelerator components is discussed based on current accelerator performance demonstrated at various scientific user facilities. Finally, comparison of the performance between the model accelerator parameters and the variation in parameter space provides a means to evaluate the potential emission architectures. A scorecard is presented to facilitate this evaluation and provides a framework for future FEL design and enablement for EUVL applications.

Impact of agricultural emission reductions on fine-particulate matter and public health

Science.gov (United States)

Pozzer, Andrea; Tsimpidi, Alexandra P.; Karydis, Vlassis A.; de Meij, Alexander; Lelieveld, Jos

2017-10-01

A global chemistry-climate model has been used to study the impacts of pollutants released by agriculture on fine-particulate matter (PM2.5), with a focus on Europe, North America, East and South Asia. Simulations reveal that a relatively strong reduction in PM2.5 levels can be achieved by decreasing agricultural emissions, notably of ammonia (NH3) released from fertilizer use and animal husbandry. The absolute impact on PM2.5 reduction is strongest in East Asia, even for small emission decreases. Conversely, over Europe and North America, aerosol formation is not immediately limited by the availability of ammonia. Nevertheless, reduction of NH3 can also substantially decrease PM2.5 concentrations over the latter regions, especially when emissions are abated systematically. Our results document how reduction of agricultural emissions decreases aerosol pH due to the depletion of aerosol ammonium, which affects particle liquid phase and heterogeneous chemistry. Further, it is shown that a 50 % reduction of agricultural emissions could prevent the mortality attributable to air pollution by ˜ 250 000 people yr-1 worldwide, amounting to reductions of 30, 19, 8 and 3 % over North America, Europe, East and South Asia, respectively. A theoretical 100 % reduction could even reduce the number of deaths globally by about 800 000 per year.

Acidifier application rate impacts on ammonia emissions from US roaster chicken houses

Science.gov (United States)

Shah, Sanjay B.; Grimes, Jesse L.; Oviedo-Rondón, Edgar O.; Westerman, Philip W.

2014-08-01

Due to its potential environmental and public health impacts, emissions of ammonia (NH3) as well as several other gases from US livestock farms may be regulated. Broiler houses are important sources of NH3 emissions. However, there are no emissions data from roaster (8-12 wk old broilers, ˜4 kg ea.) houses. Producers treat the litter in broiler houses with acidifiers, such as sodium bisulfate (SBS, NaHSO4) to reduce ammonia production and protect bird health. However, there is very little data on the effect of acidifiers, particularly at high application rates on ammonia emissions. The impact of different SBS application rates [High (0.95-1.46 kg m-2, whole house), Medium (0.73 kg m-2, whole house), Low (0.37-0.49 kg m-2, whole house), and Control (0.37-0.49 kg m-2, brood chamber)] on ammonia emissions was evaluated in commercial roaster houses over 22 months spanning eight flocks. Ammonia emission from each fan was measured with an acid scrubber that operated only when the fan operated. Emissions were calculated using >95% measured data with the rest being estimated using robust methods. Exhaust ammonia-N concentrations were inversely correlated with the SBS application rates. Emission rates on animal unit (AU, where 1 AU = 500 kg live-mass) basis (ER, g d-1 AU-1) were reduced by 27, 13, and 5%, respectively, in the High, Medium, and Low treatments vs. the Control treatment (mean: 100 g d-1 AU-1, range: 86-114 g d-1 AU-1). Emission rates for the Control treatment measured in this study on roasters were mostly higher than ERs in the literature. Differences in ERs are not only due to diet, environmental and management conditions, but also due to measurement methods.

Global and local emission impact assessment of distributed cogeneration systems with partial-load models

International Nuclear Information System (INIS)

Mancarella, Pierluigi; Chicco, Gianfranco

2009-01-01

Small-scale distributed cogeneration technologies represent a key resource to increase generation efficiency and reduce greenhouse gas emissions with respect to conventional separate production means. However, the diffusion of distributed cogeneration within urban areas, where air quality standards are quite stringent, brings about environmental concerns on a local level. In addition, partial-load emission worsening is often overlooked, which could lead to biased evaluations of the energy system environmental performance. In this paper, a comprehensive emission assessment framework suitable for addressing distributed cogeneration systems is formulated. Local and global emission impact models are presented to identify upper and lower boundary values of the environmental pressure from pollutants that would be emitted from reference technologies, to be compared to the actual emissions from distributed cogeneration. This provides synthetic information on the relative environmental impact from small-scale CHP sources, useful for general indicative and non-site-specific studies. The emission models are formulated according to an electrical output-based emission factor approach, through which off-design operation and relevant performance are easily accounted for. In particular, in order to address the issues that could arise under off-design operation, an equivalent load model is incorporated within the proposed framework, by exploiting the duration curve of the cogenerator loading and the emissions associated to each loading level. In this way, it is possible to quantify the contribution to the emissions from cogeneration systems that might operate at partial loads for a significant portion of their operation time, as for instance in load-tracking applications. Suitability of the proposed methodology is discussed with respect to hazardous air pollutants such as NO x and CO, as well as to greenhouse gases such as CO 2 . Two case study applications based on the emission

Impact of cold temperature on Euro 6 passenger car emissions.

Science.gov (United States)

Suarez-Bertoa, Ricardo; Astorga, Covadonga

2018-03-01

Hydrocarbons, CO, NOx, NH 3 , N 2 O, CO 2 and particulate matter emissions affect air quality, global warming and human health. Transport sector is an important source of these pollutants and high pollution episodes are often experienced during the cold season. However, EU vehicle emissions regulation at cold ambient temperature only addresses hydrocarbons and CO vehicular emissions. For that reason, we have studied the impact that cold ambient temperatures have on Euro 6 diesel and spark ignition (including: gasoline, ethanol flex-fuel and hybrid vehicles) vehicle emissions using the World-harmonized Light-duty Test Cycle (WLTC) at -7 °C and 23 °C. Results indicate that when facing the WLTC at 23 °C the tested vehicles present emissions below the values set for type approval of Euro 6 vehicles (still using NEDC), with the exception of NOx emissions from diesel vehicles that were 2.3-6 times higher than Euro 6 standards. However, emissions disproportionally increased when vehicles were tested at cold ambient temperature (-7 °C). High solid particle number (SPN) emissions (>1 × 10 11 # km -1 ) were measured from gasoline direct injection (GDI) vehicles and gasoline port fuel injection vehicles. However, only diesel and GDI SPN emissions are currently regulated. Results show the need for a new, technology independent, procedure that enables the authorities to assess pollutant emissions from vehicles at cold ambient temperatures. Harmful pollutant emissions from spark ignition and diesel vehicles are strongly and negatively affected by cold ambient temperatures. Only hydrocarbon, CO emissions are currently regulated at cold temperature. Therefore, it is of great importance to revise current EU winter vehicle emissions regulation. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Observation of reduction of secondary electron emission from helium ion impact due to plasma-generated nanostructured tungsten fuzz

International Nuclear Information System (INIS)

Hollmann, E M; Doerner, R P; Nishijima, D; Pigarov, A Yu

2017-01-01

Growth of nanostructured fuzz on a tungsten target in a helium plasma is found to cause a significant (∼3×) reduction in ion impact secondary electron emission in a linear plasma device. The ion impact secondary electron emission is separated from the electron impact secondary electron emission by varying the target bias voltage and fitting to expected contributions from electron impact, both thermal and non-thermal; with the non-thermal electron contribution being modeled using Monte-Carlo simulations. The observed (∼3×) reduction is similar in magnitude to the (∼2×) reduction observed in previous work for the effect of tungsten fuzz formation on secondary electron emission due to electron impact. It is hypothesized that the observed reduction results from re-absorption of secondary electrons in the tungsten fuzz. (paper)

A missing link? The case of Norway and Sweden: Does increased renewable energy production impact domestic greenhouse gas emissions?

International Nuclear Information System (INIS)

Blindheim, Bernt

2015-01-01

This article examines how the EU's RES directive will impact domestic greenhouse gas emissions in Norway and Sweden by 2020. The directive aims for a higher RES share in the energy consumption mix, and Norway and Sweden have established a common electricity certificate scheme to help achieve these RES goals. In terms of how these two national RES plans will impact domestic emissions by 2020, factors such as nuclear power, consumption changes and the energy balance must be considered. The most practical approach to evaluate the plans’ impact on emissions is to focus on changes in carbon-based consumption within the three directive sectors. The Norwegian RES action plan will not affect domestic emissions unless the electricity surplus generated by the certificate market is used to phase out fossil fuels in domestic sectors beyond the scope of the RES directive. The use of electricity to phase out fossil fuel consumption in the offshore sector would substantially reduce Norwegian emissions figures. The Swedish plan would positively impact Swedish greenhouse gas emissions; however, this impact is limited, primarily because a substantial increase in energy consumption is expected. - Highlights: • Implementation of the EU directive on use of energy from renewable sources (RES). • A comparison between Norway and Sweden. • The common green certificate market. • Does increased share of renewable energy impact on greenhouse gas emissions. • Calculations indicate that increased RES share has limited impact on emissions

High-Impact Actions for Individuals to Reduce Greenhouse Gas Emissions

Science.gov (United States)

Nicholas, K. A.; Wynes, S. C.

2015-12-01

Climate change is the result of greenhouse gas accumulation in the atmosphere, which records the aggregation of billions of individual decisions. While systemic and structural changes receive great attention for addressing climate change, the contribution that individual citizens can make is often overlooked, especially in developed countries where per-capita emissions are highest. Here we consider a broad range of individual lifestyle choices and calculate their potential to reduce greenhouse gas emissions. We find that four widely applicable high-impact actions have the potential to reduce personal emissions by more than 1 tonne CO2-equivalent per year: having one fewer child (59.2 tonnes of reductions), living car-free (2.3 tonnes), avoiding airplane travel (1.5 tonnes per flight) and eating a plant-based diet (0.82 tonnes). These actions have much greater potential to reduce emissions than commonly promoted strategies like recycling (4 times less effective than a plant-based diet) or changing lightbulbs (8 times). However, high school textbooks from Canada and government resources from the EU, USA, Canada, and Australia largely fail to mention these actions, instead focusing on incremental changes with much smaller potential impact. We conclude that climate policy should focus not only on national and international targets, but also on encouraging responsible behaviour, especially for adolescents who will grow up in the era of climate change and are poised to establish a lifelong pattern of sustainable lifestyle choices.

Exploitation Agricole des Berges : Une Strategie D'Adaptation aux ...

African Journals Online (AJOL)

et socio-économique. ... dynamique des paysages agraires et son impact sur le capital naturel surtout sur les .... favoriser leur germination et amorcer leur croissance. ..... similaires ont été relevées au Bénin où l'impact humain se traduit par le ...

Prise en charge des urgences au service d'accueil des urgences ...

African Journals Online (AJOL)

Introduction: La prise en charge des patients dans les services d'accueil des urgences est une des meilleures vitrines d'un système de santé. En Afrique subsaharienne, la gestion des urgences se heurte à des difficultés humaines et matérielles. Le but de ce travail était d'évaluer les difficultés de prise en charge au Service ...

Final report of the project. Emission of nitrogen oxides by the soils. Measures, modelization, land registry and inventory. Impact on the air quality, the climatic change and the evaluation of possibilities of these emissions reduction; Rapport final du projet. Emissions d'oxydes d'azote par les sols. Mesures, modelisation, cadastre et inventaire. Impact sur la qualite de l'air, le changement climatique, et evaluation des gisements de reduction de ces emissions

Energy Technology Data Exchange (ETDEWEB)

Serca, D.; Cortinovis, J. [LA Laboratoire d' Aerologie UMR 5560, 31 - Toulouse (France); Laville, P.; Gabrielle, B. [Institut National de Recherches Agronomiques (INRA), Environnement et Grandes Cultures, 78 - Thiverval-Grignon (France); Beekmann, M.; Ravetta, F. [Universite Pierre et Marie Curie, SA Service d' Aeronomie, 75 - Paris (France); Henault, C. [Institut National de Recherches Agronomiques (INRA-LMS) UMR Microbiologie des Sols-Geosol, 21 - Dijon (France)

2007-07-01

This project deals with NOx biosphere-atmosphere exchanges, NOx being considered as an indirect greenhouse gases (tropospheric O{sub 3} precursor). It relies on four laboratory specialized both on the soil-plant-atmosphere interface, and on the atmospheric chemistry. Methodology used bear on a set of in situ and laboratory measurements aiming at improving existing emission parameterization, or building new ones for the agro-ecosystems encountered in France or Europe. In situ measurements allowed to study the emission phenology in relation with relevant environmental parameters (meteorological, soil characteristics, and agricultural). Laboratory measurements allowed to establish an emission algorithm related to the three main parameters, that is, soil temperature, water and ammonia content. This algorithm has been adapted and simplified to spatialize the emissions at the France level. This spatialization was performed using environmental parameters accessible through data base (ECMWF) or agricultural statistics (such as nitrogen inputs, land use, crops). Spatial and temporal extrapolation allowed reaching the main objective, that is, to build a national inventory for a reference year (2002). This inventory allowed determining the contribution of NOx emitted by soil as compared to total emitted NOx, and the proportion of NOx emitted by soil due to fertilizer use. Our study, based on 57% of the French used agricultural area, and extrapolated to the whole arable surface, shows that soils would be responsible of about 5% of the total NOx emissions. On these 5%, 20%, which finally is a rather low percentage, would be linked to fertilizer use. The impact of these emissions on the atmospheric chemistry has been evaluated using the CHIMERE chemistry-transport model. We found that NOx emissions from soil would be of minor importance when compared to the industrial emissions, being a factor of ten lower in France. As a matter of consequence, the impact of the emissions on the

Climate change impacts on agriculture in 2050 under a range of plausible socioeconomic and emissions scenarios

International Nuclear Information System (INIS)

Wiebe, Keith; Islam, Shahnila; Mason-D’Croz, Daniel; Robertson, Richard; Robinson, Sherman; Lotze-Campen, Hermann; Biewald, Anne; Bodirsky, Benjamin; Müller, Christoph; Popp, Alexander; Sands, Ronald; Tabeau, Andrzej; Van Meijl, Hans; Van der Mensbrugghe, Dominique; Kavallari, Aikaterini; Willenbockel, Dirk

2015-01-01

Previous studies have combined climate, crop and economic models to examine the impact of climate change on agricultural production and food security, but results have varied widely due to differences in models, scenarios and input data. Recent work has examined (and narrowed) these differences through systematic model intercomparison using a high-emissions pathway to highlight the differences. This paper extends that analysis to explore a range of plausible socioeconomic scenarios and emission pathways. Results from multiple climate and economic models are combined to examine the global and regional impacts of climate change on agricultural yields, area, production, consumption, prices and trade for coarse grains, rice, wheat, oilseeds and sugar crops to 2050. We find that climate impacts on global average yields, area, production and consumption are similar across shared socioeconomic pathways (SSP 1, 2 and 3, as we implement them based on population, income and productivity drivers), except when changes in trade policies are included. Impacts on trade and prices are higher for SSP 3 than SSP 2, and higher for SSP 2 than for SSP 1. Climate impacts for all variables are similar across low to moderate emissions pathways (RCP 4.5 and RCP 6.0), but increase for a higher emissions pathway (RCP 8.5). It is important to note that these global averages may hide regional variations. Projected reductions in agricultural yields due to climate change by 2050 are larger for some crops than those estimated for the past half century, but smaller than projected increases to 2050 due to rising demand and intrinsic productivity growth. Results illustrate the sensitivity of climate change impacts to differences in socioeconomic and emissions pathways. Yield impacts increase at high emissions levels and vary with changes in population, income and technology, but are reduced in all cases by endogenous changes in prices and other variables. (paper)

Environmental impacts of genetically modified (GM) crop use 1996–2014: Impacts on pesticide use and carbon emissions

Science.gov (United States)

Brookes, Graham; Barfoot, Peter

2016-01-01

ABSTRACT This paper updates previous assessments of important environmental impacts associated with using crop biotechnology in global agriculture. It focuses on the environmental impacts associated with changes in pesticide use and greenhouse gas emissions arising from the use of GM crops since their first widespread commercial use in the mid 1990s. The adoption of GM insect resistant and herbicide tolerant technology has reduced pesticide spraying by 581.4 million kg (−8.2%) and, as a result, decreased the environmental impact associated with herbicide and insecticide use on these crops (as measured by the indicator, the Environmental Impact Quotient [EIQ]) by18.5%. The technology has also facilitated important cuts in fuel use and tillage changes, resulting in a significant reduction in the release of greenhouse gas emissions from the GM cropping area. In 2014, this was equivalent to removing nearly 10 million cars from the roads. PMID:27253265

Environmental impacts of genetically modified (GM) crop use 1996–2015: Impacts on pesticide use and carbon emissions

Science.gov (United States)

Brookes, Graham

2017-01-01

ABSTRACT This paper updates previous assessments of important environmental impacts associated with using crop biotechnology in global agriculture. It focuses on the environmental impacts associated with changes in pesticide use and greenhouse gas emissions arising from the use of GM crops since their first widespread commercial use in the mid-1990s. The adoption of GM insect resistant and herbicide tolerant technology has reduced pesticide spraying by 618.7 million kg (−8.1%) and, as a result, decreased the environmental impact associated with herbicide and insecticide use on these crops (as measured by the indicator, the Environmental Impact Quotient (EIQ)) by18.6%. The technology has also facilitated important cuts in fuel use and tillage changes, resulting in a significant reduction in the release of greenhouse gas emissions from the GM cropping area. In 2015, this was equivalent to removing 11.9 million cars from the roads. PMID:28414252

Dynamic impact of urbanization, economic growth, energy consumption, and trade openness on CO 2 emissions in Nigeria.

Science.gov (United States)

Ali, Hamisu Sadi; Law, Siong Hook; Zannah, Talha Ibrahim

2016-06-01

The objective of this paper is to examine the dynamic impact of urbanization, economic growth, energy consumption, and trade openness on CO 2 emissions in Nigeria based on autoregressive distributed lags (ARDL) approach for the period of 1971-2011. The result shows that variables were cointegrated as null hypothesis was rejected at 1 % level of significance. The coefficients of long-run result reveal that urbanization does not have any significant impact on CO 2 emissions in Nigeria, economic growth, and energy consumption has a positive and significant impact on CO 2 emissions. However, trade openness has negative and significant impact on CO 2 emissions. Consumption of energy is among the main determinant of CO 2 emissions which is directly linked to the level of income. Despite the high level of urbanization in the country, consumption of energy still remains low due to lower income of the majority populace and this might be among the reasons why urbanization does not influence emissions of CO 2 in the country. Initiating more open economy policies will be welcoming in the Nigerian economy as the openness leads to the reduction of pollutants from the environment particularly CO 2 emissions which is the major gases that deteriorate physical environment.

Impacts of global, regional, and sectoral black carbon emission reductions on surface air quality and human mortality

Science.gov (United States)

Anenberg, S. C.; Talgo, K.; Arunachalam, S.; Dolwick, P.; Jang, C.; West, J. J.

2011-07-01

As a component of fine particulate matter (PM2.5), black carbon (BC) is associated with premature human mortality. BC also affects climate by absorbing solar radiation and reducing planetary albedo. Several studies have examined the climate impacts of BC emissions, but the associated health impacts have been studied less extensively. Here, we examine the surface PM2.5 and premature mortality impacts of halving anthropogenic BC emissions globally and individually from eight world regions and three major economic sectors. We use a global chemical transport model, MOZART-4, to simulate PM2.5 concentrations and a health impact function to calculate premature cardiopulmonary and lung cancer deaths. We estimate that halving global anthropogenic BC emissions reduces outdoor population-weighted average PM2.5 by 542 ng m-3 (1.8 %) and avoids 157 000 (95 % confidence interval, 120 000-194 000) annual premature deaths globally, with the vast majority occurring within the source region. Most of these avoided deaths can be achieved by halving emissions in East Asia (China; 54 %), followed by South Asia (India; 31 %), however South Asian emissions have 50 % greater mortality impacts per unit BC emitted than East Asian emissions. Globally, halving residential, industrial, and transportation emissions contributes 47 %, 35 %, and 15 % to the avoided deaths from halving all anthropogenic BC emissions. These contributions are 1.2, 1.2, and 0.6 times each sector's portion of global BC emissions, owing to the degree of co-location with population globally. We find that reducing BC emissions increases regional SO4 concentrations by up to 28 % of the magnitude of the regional BC concentration reductions, due to reduced absorption of radiation that drives photochemistry. Impacts of residential BC emissions are likely underestimated since indoor PM2.5 exposure is excluded. We estimate ∼8 times more avoided deaths when BC and organic carbon (OC) emissions are halved together, suggesting

Connaissances, attitudes et pratiques des prestataires de santé des ...

African Journals Online (AJOL)

... des prestataires interrogés avaient respectivement une bonne connaissance des facteurs de risque et des moyens de dépistage. Les signes évocateurs et les examens complémentaires nécessaires au diagnostic du cancer du sein étaient connus par 15,3 % des prestataires. La définition du cancer du sein et les moyens ...

Des données locales sur les changements climatiques assurent la ...

International Development Research Centre (IDRC) Digital Library (Canada)

13 mai 2015 ... La capacité financière est un facteur essentiel pour les agriculteurs, et les options choisies dépendent des coûts perçus. Par exemple, au Malawi, 21 % des agriculteurs choisissent de ne ... Communication en vue d'un impact stratégique. L'équipe de recherche a utilisé divers outils pour communiquer les ...

Évolution des politiques environnementales et tourisme de montagne au Népal

Directory of Open Access Journals (Sweden)

Isabelle Sacareau

2009-12-01

Full Text Available Le développement du trekking au Népal a suscité des inquiétudes qui ont abouti à la création d’aires protégées sur la foi d’un scénario de crise environnementale dont les touristes et les paysans étaient jugés responsables. Devant les conflits entre la conservation et les nécessités de développement des régions concernées, la gouvernance des aires protégées a évolué dans le sens d’une meilleure prise en compte des sociétés locales. Pour autant les mesures prises ne font qu’accompagner et diriger des dynamiques touristiques plus anciennes qui s’exercent à des échelles plus vastes. Le trekking constitue ainsi un système touristique très largement aux mains des sociétés montagnardes du pays qui a permis l’amélioration de leurs conditions de vie tout en limitant ses impacts environnementaux. En ce sens le trekking répond assez largement aux principes du développement durable.Against a backdrop of environmental crisis, attributed to the impact of tourism and the practices of rural populations, Nepal has created protected areas with a view to preserving the Himalayan environment and promoting sustainable tourism in the regions concerned. Given the conflicts between conservation needs and development needs, local communities are now being given a bigger role in the governance of these protected areas. Yet the measures being taken simply accompany and guide well-established tourism dynamics that operate on a much greater scale. Trekking is thus a tourism system largely in the hands of the country’s mountain communities and is an activity that has enabled these communities to improve their living conditions while at the same time limiting environmental impacts. In this sense it is very much in line with the principles of sustainable development.

Impacts of Aging Emission Control Systems on In-Use Heavy-Duty Diesel Truck Emission Rates

Science.gov (United States)

Preble, C.; Cados, T.; Harley, R.; Kirchstetter, T.

2017-12-01

Heavy-duty diesel trucks are a major source of nitrogen oxides (NOx) and black carbon (BC) in urban environments, contributing to persistent ozone and particulate matter air quality problems. Recently, diesel particle filter (DPF) and selective catalytic reduction (SCR) emission control systems have become standard equipment on new trucks. Particle filters can also be installed as a retrofit on older engines. Prior work has shown that exhaust filters and SCR systems effectively reduce BC and NOx emission rates by up to 90 and 80%, respectively (Preble et al., ES&T 2015). There is concern, however, that DPFs may promote the formation of ultrafine particles (UFP) and increase tailpipe emissions of nitrogen dioxide (NO2). Additionally, urea-based SCR systems for NOx control may form nitrous oxide (N2O), an important contributor to stratospheric ozone depletion. The effectiveness of these emission controls has been thoroughly evaluated in the laboratory, but the long-term durability of in-use systems and their impacts on co-emitted species have not been well characterized. To evaluate the in-use performance of DPF and SCR systems, pollutant emissions from thousands of diesel trucks were measured over several years at the Port of Oakland and the Caldecott Tunnel in the San Francisco Bay Area. Pollutants present in the exhaust plumes of individual trucks were measured at high time resolution (≥1 Hz) as trucks passed under a mobile lab stationed on an overpass. Fuel-based emission factors (g pollutant emitted per kg fuel burned) were calculated for individual trucks and linked via recorded license plates to vehicle attributes, including engine model year and installed emission control systems. Use of DPFs reduced the BC emission rate by up to 95% at both locations. SCR systems were more effective at reducing NOx emissions under the uphill, highway driving conditions at the Caldecott Tunnel. The emission rates of co-emitted species NO2, UFP, and N2O depended on driving

The relative magnitude of the impacts and effects of GHG-related emission reductions

International Nuclear Information System (INIS)

Chiotti, Q.; Urquizo, N.

2000-01-01

A preliminary assessment of the current knowledge related to the co-benefits associated with climate change mitigation was provided in this document. One of the benefits of the reduction of greenhouse gas emissions is the reduction of other pollutants like sulphur dioxide, nitrogen oxides, carbon monoxide, volatile organic compounds, particulate matter, ground-level ozone, heavy metals and other toxic pollutants. Since these pollutants have an effect on acid deposition, ozone depletion and air quality, the environment, social welfare and human health, this paper provided an initial outline of the complex processes, interactions and uncertainties associated with this issue. Fossil fuels represent the major source of greenhouse gas (GHG) emissions in Canada. The reduction of emissions of GHG could have an impact on the Long Range Transport of air toxic substances, would help increase oxygen concentrations in the Northern Hemisphere, and lead to less carbon monoxide being released in the atmosphere, among others effects. Reductions of GHG emissions would also have an impact on ecosystems by reducing ground-level ozone concentrations. There would be less acid deposition and more dissolved organic carbon, allowing less ultraviolet-B penetration in aquatic ecosystems. In the case of human health, improved air quality impacts on the avoidance of premature mortality and reduced morbidity. Numerous other co-benefits were listed and discussed in this document. The first section stated the purpose and objectives. In section 2, that authors described the science and policy context and discussed building an analytical framework in section 3. The impact of GHG emission reductions on atmospheric pollution and ecosystems was dealt with in section 4 and section 5 was devoted to providing an assessment of the relative magnitude of effects. In section 6, the significance of scope was reviewed, and the authors concluded with section 7 in which they discussed the next steps: phase II

Impacts of Federal Tax Credit Extensions on Renewable Deployment and Power Sector Emissions

Energy Technology Data Exchange (ETDEWEB)

Mai, Trieu [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cole, Wesley [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lantz, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Marcy, Cara [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sigrin, Benjamin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-02-01

Federal tax credits for renewable energy (RE) have served as one of the primary financial incentives for RE deployment over the last two decades in the United States. In December 2015, the wind power production tax credit and solar investment tax credits were extended for five years as part of the Consolidated Appropriations Act of 2016. This report explores the impact that these tax credit extensions might have on future RE capacity deployment and power sector carbon dioxide (CO2) emissions. The analysis examines the impacts of the tax credit extensions under two distinct natural gas price futures as natural gas prices have been key factors in influencing the economic competitiveness of new RE development. The analysis finds that, in both natural gas price futures, RE tax credit extensions can spur RE capacity investments at least through the early 2020s and can help lower emissions from the U.S. electricity system. More specifically, the RE tax credit extensions are estimated to drive a net peak increase of 48-53 GW in installed RE capacity in the early 2020s -- longer term impacts are less certain. In the longer term after the tax credits ramp down, greater RE capacity is driven by a combination of assumed RE cost declines, rising fossil fuel prices, and other clean energy policies such as the Clean Power Plan. The tax credit extension-driven acceleration in RE capacity development can reduce fossil fuel-based generation and lower electric sector CO2 emissions. Cumulative emissions reductions over a 15-year period (spanning 2016-2030) as a result of the tax credit extensions are estimated to range from 540 to 1420 million metric tonnes CO2. These findings suggest that tax credit extensions can have a measurable impact on future RE deployment and electric sector CO2 emissions under a range of natural gas price futures.

Usages des TIC et socialisation professionnelle des enseignants-chercheurs

OpenAIRE

Lavielle-Gutnik, Nathalie; Massou, Luc

2013-01-01

En prenant appui sur une nouvelle analyse des données recueillies dans l’enquête Tec-Meus (2008-2011, MSH Lorraine) sur la place accordée par des enseignants-chercheurs en sciences humaines et sociales aux technologies de l’information et de la communication (TIC) dans leur activité d’enseignement, nous souhaitons nous focaliser dans cet article sur la compréhension des processus de socialisation professionnelle en jeu dans leur usage déclaré des TIC. Par socialisation professionnelle, nous e...

Evaluer des études de gestion des entreprises : combiner des éléments principales avec des éléments pratiques

NARCIS (Netherlands)

Pennink, B.J.W.

2002-01-01

Evaluer la recherche de gestion demande une combinaison des critères classiques et des critères pratiques. Par cette combinaison il est possible de trouver une réponse cerrecte concernant la validité et l'effet de la recherche. Dans cet article nous allons décrire comment une combinaison des

Contribution to the experimental study of excited levels of some light nuclei by using the method of angular correlation of internal conversion pairs and monopolar pairs; Contribution a l'etude experimentale de niveaux excites de quelques noyaux legers par la methode des Correlations angulaires des paires de conversion interne Et des paires monopolaires

Energy Technology Data Exchange (ETDEWEB)

Armbruster, Raymond

1950-07-01

In a first part, the author presents a brief theory of angular correlations of internal conversion pairs and monopolar pairs, and indicates the complete formulations which are used to compute all the angular correlations corresponding to the performed experiments. In a second part, he describes a beta spectrometer, outlines factors which govern the energy resolving power, and the peculiarity of summation of two pulses proportional to the energy of the electron and positron which build up an internal pair. In a third part, the author reports experiments of angular correlations, indicates the shapes of monopolar spectra for different angles between electron and positron emission directions, determines the multipolarity of gamma radiations from the first excited levels of {sup 13}C and {sup 12}C, and gives the angular moments, parity and isobaric spin of two excited levels of the {sup 12}C [French] Dans la premiere partie de notre travail, nous exposons une theorie sommaire des correlations angulaires des paires de conversion interne et des paires monopolaires. A la fin de cette premiere partie sont indiquees les formules completes, qui nous ont servi a calculer pratiquement toutes les correlations angulaires correspondant a nos experiences. Dans la deuxieme partie, nous decrivons un spectrometre beta a scintillation. Nous insistons surtout sur les elements qui determinent le pouvoir de resolution en energie et sur la particularite de sommation de deux impulsions proportionnelles a l'energie de l'electron et du positron formant une paire interne. Dans la troisieme partie, nous exposons nos experiences de correlations angulaires. Nous avons repris une mesure precise de la correlation angulaire des paires monopolaires provenant du niveau 6,05 Mev de l'Oxygene 16. Il nous a ete egalement possible de donner l'allure des spectres monopolaires pour differents angles formes par les directions d'emission de l'electron et du positron. Nous avons determine par la methode des

Aspects des Onychomycoses chez des patients camerounais de ...

African Journals Online (AJOL)

... biologiques et évolutifs des onychomycoses chez des patients camerounais. Méthode : Il s'agit d'une étude rétrospective et descriptive menée de mars 2011 à mars 2014 dans l'unité de dermatologie de l'hôpital général de Douala (HGD), incluant des patients chez lesquels le diagnostic d'onychomycose avait été posé.

Impacts of nationally determined contributions on 2030 global greenhouse gas emissions: uncertainty analysis and distribution of emissions

Science.gov (United States)

Benveniste, Hélène; Boucher, Olivier; Guivarch, Céline; Le Treut, Hervé; Criqui, Patrick

2018-01-01

Nationally Determined Contributions (NDCs), submitted by Parties to the United Nations Framework Convention on Climate Change before and after the 21st Conference of Parties, summarize domestic objectives for greenhouse gas (GHG) emissions reductions for the 2025-2030 time horizon. In the absence, for now, of detailed guidelines for the format of NDCs, ancillary data are needed to interpret some NDCs and project GHG emissions in 2030. Here, we provide an analysis of uncertainty sources and their impacts on 2030 global GHG emissions based on the sole and full achievement of the NDCs. We estimate that NDCs project into 56.8-66.5 Gt CO2eq yr-1 emissions in 2030 (90% confidence interval), which is higher than previous estimates, and with a larger uncertainty range. Despite these uncertainties, NDCs robustly shift GHG emissions towards emerging and developing countries and reduce international inequalities in per capita GHG emissions. Finally, we stress that current NDCs imply larger emissions reduction rates after 2030 than during the 2010-2030 period if long-term temperature goals are to be fulfilled. Our results highlight four requirements for the forthcoming ‘climate regime’: a clearer framework regarding future NDCs’ design, an increasing participation of emerging and developing countries in the global mitigation effort, an ambitious update mechanism in order to avoid hardly feasible decarbonization rates after 2030 and an anticipation of steep decreases in global emissions after 2030.

Impact of Agricultural Emission Reductions on Fine Particulate Matter and Public Health

Science.gov (United States)

Pozzer, A.; Tsimpidi, A.; Karydis, V.; De Meij, A.; Lelieveld, J.

2017-12-01

A global chemistry-climate model has been used to study the impacts of pollutants released by agriculture on fine particulate matter (PM2.5), with a focus on Europe, North America, South and East Asia. Hypothetical reduction of agricultural emission of 50%, 66% and 100% have been simulated and compared with the reference simulation. The simulations results reveal that a relatively strong reduction in PM2.5 levels can be achieved by decreasing agricultural emissions, and this effect can almost be exclusively explain by the reduction of ammonia (NH3) emissions, released from fertilizer use and animal husbandry. The absolute impact on PM2.5 reduction is strongest in East Asia, even for small emission decreases, although the relative reduction is very low (below 13% for a full removal of agricultural emissions) . Conversely, over Europe and North America, aerosol formation is not directly limited by the availability of ammonia. Nevertheless, reduction of NH3 can also substantially decrease PM2.5concentrations over the latter regions, especially when emissions are abated systematically and an ammonia limited regions of aerosol growth is reached. Further, our results document how reduction of agricultural emissions decreases aerosol pH due to the depletion of aerosol ammonium, which affects particle liquid phase and heterogeneous chemistry. It is calculated that ammonia emission controls could reduce the particle pH up to 1.5 pH-units in East Asia during winter, and more than 1.7 pH-units in South Asia, theoretically assuming complete agricultural emission removal, which could have repercussions for the reactive uptake of gases from the gas phase and the outgassing of relative weak acids. It is finally shown that a 50% reduction of agricultural emissions could prevent the mortality attributable to air pollution by 250 thousands people per year worldwide, amounting to reductions of 30%, 19% , 8% and 3% over North America, Europe and South Asia and East Asia, respectively

Estimating the Impact of US Agriculture Subsidies on Greenhouse Gas Emissions

Science.gov (United States)

Eshel, G.; Martin, P. A.

2006-12-01

It has been proposed in the popular media that US agricultural subsidies contribute deleteriously to both the American diet and environment. In this view, subsidies render mostly corn-based, animal products and sweeteners artificically cheap, leading to enhanced consumption. Problems accompanying this structure mentioned include enhanced meat, fat and sugar consumption and the associated enhancement of obesity, cardiovascular diseases, type II diabetes and possible various types of cancer, as well as air, soil and water pollution. Often overlooked in these discussions is the potential enhancement of greenhouse gas emissions accompanying this policy-based steering of food consumption toward certain products at the expense of others, possibly more nutritionally and environmentally benign. If such enhancements are in fact borne out by data, the policies that give rise to them will prove to constitute government-sponsored enhancement of greenhouse gas emissions, in contrast to any climate change mitigation efforts. If so, they represent low- hanging fruits in the national effort to reduce greenhouse gas emissions which may one day be launched. Agriculture subsidies impact the emissions of CO2 (by direct energy consumption), nitrous oxide (by land use alteration and manure management), and methane (by ruminant digestion and manure treatment). Quantifying the impacts of agricultural subsidies is complicated by many compounding and conflicting effects (many related to human behavior rather than the natural sciences) and the relatively short data timeseries. For example, subsidy policies change over time, certain subsidy types are introduced or eliminated, food preferences change as nutritional understanding (or propaganda) shift, etc. Despite the difficulties, such quantification is crucial to better estimate the overall effect and variability of dietary choices on greenhouse gas emissions, and ultimately minimize environmental impacts. In this study, we take preliminary

Professional practice assessment. Pertinence of positron emission tomography clinical indications in oncology; Evaluation des pratiques professionnelles. Pertinence des indications de la tomographie a emission de positons en cancerologie

Energy Technology Data Exchange (ETDEWEB)

Le Stanc, E.; Tainturier, C. [Hopital Foch, Service de Medecine Nucleaire, 92 - Suresnes (France); Swaenepoel, J. [Hopital Foch, Cellule Qualite, 92 - Suresnes (France)

2009-09-15

Introduction As part of the health care quality and safety policy in France, Professional Practice Assessment (P.P.A.) are mandatory in the health services 'certification' process. We present our study regarding the pertinence of Positron Emission Tomography (PET) indications in oncology. Materials and methods A multidisciplinary task group used the Quick Audit method with two rounds of 100 request forms each. The assessment list of criteria comprised four items of decreasing relevance grading the PET scans clinical indications, which were derived from the three French published guidelines (S.O.R. [F.N.C.L.C.C]., 'Guide du bon usage des examens d'imagerie medicale' [S.F.R.-S.F.M.N.], 'Guide pour la redaction de protocoles pour la TEP au F.D.G. en cancerologie' [S.F.M.N.]) and five additional items: clinical information, patient's body weight, previous treatments dates, diabetes, claustrophobia. Results The first round showed that 68% of the requested scans corresponded to the two most relevant groups of indications (S.O.R. Standards and Options). The request forms were correctly filled in regarding the clinical information, but this was not the case for the other items we tested. Several actions were conducted: dedicated PET request form, availability of the S.O.R. on the hospital intranet, boost of the referring physicians awareness during the multidisciplinary oncology meetings (Reunions de Concertation Pluridisciplinaires RCP). The second round showed a better pertinence of the PET scans indications (75% versus 68%); the patient's body weight was more frequently mentioned on the request form. Discussion This study is an example of P.P.A. in our discipline. It led to an improvement of the oncologic PET scans clinical indications in our hospital. This work is pursued in everyday discussion with the referring clinicians, especially during the RCP. (authors)

Impact of agricultural emission reductions on fine-particulate matter and public health

Directory of Open Access Journals (Sweden)

A. Pozzer

2017-10-01

Full Text Available A global chemistry-climate model has been used to study the impacts of pollutants released by agriculture on fine-particulate matter (PM2.5, with a focus on Europe, North America, East and South Asia. Simulations reveal that a relatively strong reduction in PM2.5 levels can be achieved by decreasing agricultural emissions, notably of ammonia (NH3 released from fertilizer use and animal husbandry. The absolute impact on PM2.5 reduction is strongest in East Asia, even for small emission decreases. Conversely, over Europe and North America, aerosol formation is not immediately limited by the availability of ammonia. Nevertheless, reduction of NH3 can also substantially decrease PM2.5 concentrations over the latter regions, especially when emissions are abated systematically. Our results document how reduction of agricultural emissions decreases aerosol pH due to the depletion of aerosol ammonium, which affects particle liquid phase and heterogeneous chemistry. Further, it is shown that a 50 % reduction of agricultural emissions could prevent the mortality attributable to air pollution by  ∼ 250 000 people yr−1 worldwide, amounting to reductions of 30, 19, 8 and 3 % over North America, Europe, East and South Asia, respectively. A theoretical 100 % reduction could even reduce the number of deaths globally by about 800 000 per year.

Architecture, des normes et des systèmes d'information libres, phase ...

International Development Research Centre (IDRC) Digital Library (Canada)

Architecture, des normes et des systèmes d'information libres, phase II (OASIS II) - Renforcement des capacités dans l'ensemble de l'Afrique. Sur presque tout le continent africain, la prestation des services de santé est limitée en raison des maigres ressources disponibles et de la charge de morbidité de plus en plus ...

Livestock-related greenhouse gas emissions: impacts and options for policy makers

International Nuclear Information System (INIS)

Garnett, Tara

2009-01-01

Research shows that livestock account for a significant proportion of greenhouse gas (GHG) emissions and global consumption of livestock products is growing rapidly. This paper reviews the life cycle analysis (LCA) approach to quantifying these emissions and argues that, given the dynamic complexity of our food system, it offers a limited understanding of livestock's GHG impacts. It is argued that LCA's conclusions need rather to be considered within a broader conceptual framework that incorporates three key additional perspectives. The first is an understanding of the indirect second order effects of livestock production on land use change and associated CO 2 emissions. The second compares the opportunity cost of using land and resources to rear animals with their use for other food or non-food purposes. The third perspective is need-the paper considers how far people need livestock products at all. These perspectives are used as lenses through which to explore both the impacts of livestock production and the mitigation approaches that are being proposed. The discussion is then broadened to consider whether it is possible to substantially reduce livestock emissions through technological measures alone, or whether reductions in livestock consumption will additionally be required. The paper argues for policy strategies that explicitly combine GHG mitigation with measures to improve food security and concludes with suggestions for further research.

Estimate of Fuel Consumption and GHG Emission Impact on an Automated Mobility District: Preprint

Energy Technology Data Exchange (ETDEWEB)

Chen, Yuche; Young, Stanley; Gonder, Jeff; Qi, Xuewei

2015-12-11

This study estimates the range of fuel and emissions impact of an automated-vehicle (AV) based transit system that services campus-based developments, termed an automated mobility district (AMD). The study develops a framework to quantify the fuel consumption and greenhouse gas (GHG) emission impacts of a transit system comprised of AVs, taking into consideration average vehicle fleet composition, fuel consumption/GHG emission of vehicles within specific speed bins, and the average occupancy of passenger vehicles and transit vehicles. The framework is exercised using a previous mobility analysis of a personal rapid transit (PRT) system, a system which shares many attributes with envisioned AV-based transit systems. Total fuel consumption and GHG emissions with and without an AMD are estimated, providing a range of potential system impacts on sustainability. The results of a previous case study based of a proposed implementation of PRT on the Kansas State University (KSU) campus in Manhattan, Kansas, serves as the basis to estimate personal miles traveled supplanted by an AMD at varying levels of service. The results show that an AMD has the potential to reduce total system fuel consumption and GHG emissions, but the amount is largely dependent on operating and ridership assumptions. The study points to the need to better understand ride-sharing scenarios and calls for future research on sustainability benefits of an AMD system at both vehicle and system levels.

L'exode des cerveaux et le renforcement des capacités en Afrique ...

International Development Research Centre (IDRC) Digital Library (Canada)

1 févr. 2011 ... Ce phénomène ébranle les assises économiques et politiques de bien des pays africains. ... le défi consiste à recruter ces cerveaux. ... des missions africaines, des organisations non gouvernementales et des groupes de la diaspora réunis pour parler de l'exode des cerveaux en Afrique et des stratégies à ...

Les impacts humains des changements organisationnels autour des TIC Human impacts of organizational changes based on ITC Impactos humanos de los cambios organizacionales en torno a los TIC

Directory of Open Access Journals (Sweden)

Robert Picard

2007-10-01

Full Text Available La taille des systèmes mis en place dans les grandes organisations, leur caractère exogène par rapport aux pratiques de l’entreprise (progiciels de gestion intégrés, posent des défis relativement nouveaux, difficiles à relever pour les acteurs. En effet, les métiers des informaticiens comme ceux des utilisateurs en sont le plus souvent profondément affectés.Les informaticiens doivent réviser leur mode d’action, révision qui s’accompagne d’une moindre autonomie, d’exigences de coopération plus élevées, et d’une multidisciplinarité à laquelle ils n’ont pas nécessairement été préparés.Les professionnels utilisateurs peuvent perdre des repères professionnels historiques, changement accompagné d’une révision des pratiques, de la modification des structures et de l’environnement de travail. Ils doivent parfois acquérir de nouvelles qualifications, de façon coûteuse, et certains peuvent perdre leur travail.Ces problématiques seront illustrées par deux situations concrètes très récentes, observées dans un grand groupe de service, pour chacune des populations.Many organizational changes are related to (or initiated by the introduction of information and communication technology (ICT tools.The size of the systems implemented in large organizations, their external nature vis-à-vis the company’s practices (Enterprise Resource Planning are rather new challenges, which are difficult for the actors to tackle. In fact, the jobs of data processing people as well as of professional users are often the most affected.Data processing people must revise their way of doing things, a change that is accompanied by a loss of autonomy and greater demands for cooperation and multidisciplinarity that they are not necessarily prepared for.Professional users may lose some historical guidelines, a change that is accompanied by a review of their practices, organizational changes, and changes in the work environment. They

Impacts of global, regional, and sectoral black carbon emission reductions on surface air quality and human mortality

Directory of Open Access Journals (Sweden)

S. C. Anenberg

2011-07-01

Full Text Available As a component of fine particulate matter (PM_2.5, black carbon (BC is associated with premature human mortality. BC also affects climate by absorbing solar radiation and reducing planetary albedo. Several studies have examined the climate impacts of BC emissions, but the associated health impacts have been studied less extensively. Here, we examine the surface PM_2.5 and premature mortality impacts of halving anthropogenic BC emissions globally and individually from eight world regions and three major economic sectors. We use a global chemical transport model, MOZART-4, to simulate PM_2.5 concentrations and a health impact function to calculate premature cardiopulmonary and lung cancer deaths. We estimate that halving global anthropogenic BC emissions reduces outdoor population-weighted average PM_2.5 by 542 ng m⁻³ (1.8 % and avoids 157 000 (95 % confidence interval, 120 000–194 000 annual premature deaths globally, with the vast majority occurring within the source region. Most of these avoided deaths can be achieved by halving emissions in East Asia (China; 54 %, followed by South Asia (India; 31 %, however South Asian emissions have 50 % greater mortality impacts per unit BC emitted than East Asian emissions. Globally, halving residential, industrial, and transportation emissions contributes 47 %, 35 %, and 15 % to the avoided deaths from halving all anthropogenic BC emissions. These contributions are 1.2, 1.2, and 0.6 times each sector's portion of global BC emissions, owing to the degree of co-location with population globally. We find that reducing BC emissions increases regional SO₄ concentrations by up to 28 % of the magnitude of the regional BC concentration reductions, due to reduced absorption of radiation that drives photochemistry. Impacts of residential BC emissions are likely underestimated since indoor PM_2.5 exposure is excluded. We estimate ∼8 times

Impact of distributed and independent power generation on greenhouse gas emissions: Sri Lanka

International Nuclear Information System (INIS)

Wijayatunga, P.D.C.; Shrestha, R.M.

2004-01-01

Sri Lanka has a hydropower dominated power system with approximately two thirds of its generation capacity based on large hydro plants. The remaining one third are based on oil fired thermal generation with varying technologies, such as oil steam, Diesel, gas turbines and combined cycle plants. A significant portion of this capacity is in operation as independent power plants (IPPs). In addition to these, Sri Lanka presently has about 40 MWs of mini-hydro plants, which are distributed in the highlands and their surrounding districts, mainly connected to the primary distribution system. Further, there are a few attempts to build fuel wood fired power plants of small capacities and connect them to the grid in various parts of the country. The study presented in this paper investigates the impact of these new developments in the power sector on the overall emissions and the greenhouse gas (GHG) emissions in particular. It examines the resulting changes to the emissions and costs in the event of developing the proposed coal power plant as an IPP under different investment and operational conditions. The paper also examines the impact on emissions with 80 MWs of distributed power in different capacities of wind, mini-hydro and wood fired power plants. It is concluded that grid connected, distributed power generation (DPG) reduces emissions, with only a marginal increase in overall costs, due to the reduction in transmission and distribution network losses that result from the distributed nature of generation. These reductions can be enhanced by opting for renewable energy based DPGS, as the case presented in the paper, and coupling them with demand side management measures. It is also concluded that there is no impact on overall emissions by the base load IPPs unless they are allowed to change over to different fuel types and technologies. (author)

The role of population density on the impact of urbaniza-tion on GHG emissions in China

Science.gov (United States)

Liu, Yonghong; Gao, Chaochao; Lu, Yingying

2017-04-01

Urbanization directly drives rural to urban population migration and indirectly causes west to east migration in China, two phenomena that may significantly impact China's greenhouse gas emissions given its huge population and vast difference between the western rural and eastern urban areas. These two phenomena were analyzed by using emissions as a per capita term, and extending the impact from the traditional urbanization rate effect to include population density effect. The results show that population density has actually been the dominant demographic player in changing per capita emissions for the past two decades in China, and its elasticity changed from positive in economically less-developed provinces to negative for the developed provinces. This study provides a new perspective in the study of the relationship between urbanization and greenhouse gas emissions, and the results indicate that population density change should be taken into account to accurately assess the impact of urbanization.

GENOMIQUE ET LIPIDES Génomique et métabolisme des lipides des plantes

Directory of Open Access Journals (Sweden)

Delseny Michel

2002-03-01

Full Text Available Il existe dans les bases de données publiques une énorme quantité de séquences d’ADN dérivées de plantes, et notamment la séquence complète du génome d’Arabidopsis thaliana, une plante modèle pour les oléagineux, proche parente du colza. Ces données constituent une ressource importante non seulement pour la compréhension de métabolisme lipidique et de sa régulation, mais aussi pour la sélection et le développement de variétés nouvelles d’oléagineux produisant davantage d’huiles ou des huiles de composition nouvelle. Cette abondance de séquences peut être exploitée, en utilisant les recherches d’homologies, pour identifier les gènes, pour obtenir des informations sur leur fonction, comme pour repérer des gènes candidats codant des fonctions nouvelles. L’analyse de ces bases de données a révélé que la majeure partie des gènes codant des enzymes impliquées dans le métabolisme lipidique appartient à des petites familles multigéniques, reflétant la diversification des fonctions des isoformes. Une analyse du catalogue des ADNc séquencés en aveugle reflète les niveaux d’expression des différents gènes et fournit un aperçu des régulations des flux au travers des voies métaboliques conduisant à la biosynthèse des lipides de réserve. La disponibilité de mutants et de lignées transgéniques d’Arabidopsis et le développement de puces à ADN qui permettent l’analyse simultanée de plusieurs milliers de gènes conduiront à une meilleure compréhension des facteurs qui régulent le métabolisme des huiles dans les graines. Une telle connaissance facilitera la manipulation de la composition des huiles et des quantités produites dans les graines.

Gestion des risques

CERN Document Server

Louisot, Jean-Paul

2009-01-01

Depuis le début du lie siècle, la gestion des risques connaît une véritable révolution culturelle. Jusqu'alors fonction technique, centrée autour de l'achat de couverture d'assurances, elle est devenue une discipline managériale et transversale : une valise d'instruments que chaque manager doit connaître et appliquer quels que soient son domaine de compétence et ses missions au sein de l'organisation. En effet, la gestion des risques est une culture qui doit être assimilée par chacun des acteurs. C'est précisément l'ambition des 101 questions rassemblées dans cet ouvrage : apporter à chaque manager d'entreprise, de collectivité, d'établissement de santé..., des réponses claires au " pourquoi " et au " comment " : Comment identifier les risques ? Comment analyser les risques ? Quels sont les objectifs de la gestion des risques ? Une carte des risques pour quoi faire ? Pourquoi faut-il financer les risques ? Les entreprises ont-elles des responsabilités pénales ? En quoi consiste la gestion...

Comportement des polluants des eaux pluviales urbaines en ...

African Journals Online (AJOL)

développement et la croissance des organismes vivant dans l'eau et particulièrement les micro- organismes. Le suivi des températures enregistrées oscille entre 9 et 16°C dans les trois sites d'observation durant la période ... de la lumière du soleil. Le site C est bien aéré et .... Effets de différents modes de gestion des eaux ...

Study of luminous emissions associated to electron emissions in radiofrequency cavities; Etude des emissions lumineuses associees aux emissions electroniques dans les cavites hyperfrequences

Energy Technology Data Exchange (ETDEWEB)

Maissa, S

1996-11-26

This study investigates luminous emissions simultaneously to electron emissions and examines their features in order to better understand the field electron emission phenomenon. A RF cavity, operating at room temperature and in pulsed mode, joined to a sophisticated experimental apparatus has been especially developed. The electron and luminous emissions are investigated on cleaned or with metallic, graphitic and dielectric particles contaminated RF surfaces in order to study their influence on these phenomena. During the surface processing, unstable luminous spots glowing during one RF pulse are detected. Their apparition is promoted in the vicinity of the metallic particles or scratches. Two hypotheses could explain their origin: the presence of micro-plasmas associated to electronic explosive emission during processing or the thermal radiation of the melted metal during this emission. Stable luminous spots glowing during several RF pulses are also detected and appear to increase on RF surfaces contaminated with dielectric particles, leading to strong and explosive luminous emissions. Two interpretations are considered: the initiation of surface breakdowns on the dielectric particles or the heating by the RF field at temperatures sufficiently intense to provoke their thermal radiation then their explosion. Finally a superconducting cavity has been adapted to observe luminous spots, which differ from the former ones bu their star shape and could be associated to micro-plasmas, revealed by the starbursts observed on superconducting cavity walls. (author) 102 refs.

Report of the seminar modeling of pollutants emissions by road transport; Compte-rendu du seminaire modelisation des emissions de polluants par le transport routier

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

This seminar was organised by A.D.E.M.E. around the following themes: uncertainties and sensitivity analysis of the C.O.P.E.R.T. 3 model (computer programme to calculate emissions from road transport), presentation of studies using the C.O.P.E.R.T. 3 model for the estimation of road transport emissions, the future of the modeling of transport emissions from C.O.P.E.R.T.3 to A.R.T.E.M.I.S. (assessment and reliability of transport emission models and inventory systems). The interventions were as follow: uncertainties and sensitivity analysis of the C.O.P.E.R.T. 3 model, emissions from road transport in the E.S.C.O.M.P.T.E. programme (study of sensitivity), analysis of sensitivity at the level of temporal aggregation of the spatialized traffic (to evaluate the sensitivity of an inventory at the level of temporal aggregation of traffic data on an important geographic area) application in the case of the I.N.T.E.R.R.E.G. project (Alsace), the road transport part of the regional plan for air quality in Bourgogne taking into account the road network, intercomparison of tools and inventory methods of road transport emissions, evolution of the French automobile park until 2005 and new projections, application of C.O.P.E.R.T. 3 to the French context a new version of I.M.P.A.C.T.- A.D.E.M.E., the European project A.R.T.E.M.I.S. structures novelties considered for the road transport emissions modeling. (N.C.)

Caractérisation des plantes médicinales à flavonoïdes des marchés ...

African Journals Online (AJOL)

Les espèces guinéo-congolaises sont les plus abondantes et le mode de dissémination majoritaire des diaspores est la zoochorie. Les plantes à flavonoïdes les plus utilisées sont : Combretum micranthum, Aloe vera, Ageratum conyzoïdes et Cylicodiscus gabonensis. Elles rentrent dans le traitement de 73 maladies parmi ...

Biomass District Energy Trigeneration Systems: Emissions Reduction and Financial Impact

International Nuclear Information System (INIS)

Rentizelas, A.; Tolis, A.; Tatsiopoulos, I.

2009-01-01

Biomass cogeneration is widely used for district heating applications in central and northern Europe. Biomass trigeneration on the other hand, constitutes an innovative renewable energy application. In this work, an approved United Nations Framework Convention on Climate Change baseline methodology has been extended to allow the examination of biomass trigeneration applications. The methodology is applied to a case study in Greece to investigate various environmental and financial aspects of this type of applications. The results suggest that trigeneration may lead to significant emissions reduction compared to using fossil fuels or even biomass cogeneration and electricity generation. The emissions reduction achieved may be materialized into a considerable revenue stream for the project, if traded through a trading mechanism such as the European Union Greenhouse Gas Emission Trading Scheme. A sensitivity analysis has been performed to compensate for the high volatility of the emission allowances' value and the immaturity of the EU Trading Scheme, which prevent a reliable estimation of the related revenue. The work concludes that emission allowances trading may develop into one of the major revenue streams of biomass trigeneration projects, significantly increasing their financial yield and attractiveness. The impact on the yield is significant even for low future values of emission allowances and could become the main income revenue source of such projects, if emission allowances increase their value substantially. The application of trigeneration for district energy proves to lead to increased environmental and financial benefits compared to the cogeneration or electricity generation cases

TIC ET PERFORMANCE D'ENTREPRISE : ÉTUDE D'IMPACT - CAS ...

African Journals Online (AJOL)

impacts de la numérisation sur l'organisation et la gestion des entreprises économiques ... OCDE : Mesurer les impacts des TIC au moyen des statistiques officielles, ...... au-teur, publié dans, La comptabilité, le contrôle et l'audit entre.

Transient Climate Impacts for Scenarios of Aerosol Emissions from Asia: A Story of Coal versus Gas

Science.gov (United States)

Grandey, B. S.; Cheng, H.; Wang, C.

2014-12-01

Projections of anthropogenic aerosol emissions are uncertain. In Asia, it is possible that emissions may increase if business continues as usual, with economic growth driving an increase in coal burning. But it is also possible that emissions may decrease rapidly due to the widespread adoption of cleaner technology or a shift towards non-coal fuels, such as natural gas. In this study, the transient climate impacts of three aerosol emissions scenarios are investigated: an RCP4.5 (Representative Concentration Pathway 4.5) control; a scenario with reduced Asian anthropogenic aerosol emissions; and a scenario with enhanced Asian anthropogenic aerosol emissions. A coupled atmosphere-ocean configuration of CESM (Community Earth System Model), including CAM5 (Community Atmosphere Model version 5), is used. Enhanced Asian aerosol emissions are found to delay global mean warming by one decade at the end of the century. Aerosol-induced suppression of the East Asian and South Asian summer monsoon precipitation occurs. The enhanced Asian aerosol emissions also remotely impact precipitation in other parts of the world: over the Sahel, West African monsoon precipitation is suppressed; and over Australia, austral summer monsoon precipitation is enhanced. These remote impacts on precipitation are associated with a southward shift of the ITCZ. The aerosol-induced sea surface temperature (SST) response appears to play an important role in the precipitation changes over South Asia and Australia, but not over East Asia. These results indicate that energy production in Asia, through the consequent aerosol emissions and associated radiative effects, might significantly influence future climate both locally and globally.

Impact des changements climatiques sur l’agriculture dans la plaine de Jeffara sud-est tunisien

Directory of Open Access Journals (Sweden)

Houcine Jeder

2013-12-01

Full Text Available Cette étude évalue la vulnérabilité de l’agriculture dans la plaine de Jeffera sud-est tunisien aux changements climatiques en utilisant la méthode Ricardienne. Cette méthode consiste à exprimer les revenus nets agricoles en fonction des variables climatiques, édaphiques et socio-économiques. Ces modèles ricardiens ont été testés sur la base des données d’une enquête réalisée dans le cadre de projet de développement dans la plaine Jeffera pour la compagne agricole 2002-2003.  Ces modèles ont permis d’exprimer d’une part la relation qui existe entre le revenu agricole et les variables climatiques (température et précipitation et d’autre part, d’analyser la sensibilité des revenus agricoles par rapport à ces variables climatiques. Des simulations ont été faites sur la base de scenario A2 résultat de la projection faite par le modèle HadCM3 à l’échelle nationale et régionale de la Tunisie.Les résultats de l’étude ont montré que la relation entre le revenu agricole et le climat est non linéaire. De même, les effets négatifs de certaines options d’adaptation ont montré que  l’agriculture dans la plaine de Jeffera est une agriculture paysanne basée sur le travail familial qui nécessite aujourd’hui un capital financier important et une marge de modernisation afin d’améliorer l’activité agricole dans les années futures. Tandis que les effets positifs de certaines autres options peuvent être servir comme des points de réflexion dans l’élaboration des stratégies d’adaptation aux changements climatiques comme l’utilisation des nouvelles technologies d’irrigation et l’intégration de l’activité de l’élevage dans l’exploitation agricole.

Etudes optiques de nouveaux materiaux laser: Des orthosilicates dopes a l'ytterbium: Le yttrium (lutetium,scandium) pentoxide de silicium

Science.gov (United States)

Denoyer, Aurelie

La decouverte et l'elaboration de nouveaux materiaux laser solides suscitent beaucoup d'interet parmi la communaute scientifique. En particulier les lasers dans la gamme de frequence du micron debouchent sur beaucoup d'applications, en telecommunication, en medecine, dans le domaine militaire, pour la, decoupe des metaux (lasers de puissance), en optique non lineaire (doublage de frequence, bistabilite optique). Le plus couramment utilise actuellement est le Nd:YAG dans cette famille de laser, mais des remplacants plus performants sont toujours recherches. Les lasers a base d'Yb3+ possedent beaucoup d'avantages compares aux lasers Nd3+ du fait de leur structure electronique simple et de leur deterioration moins rapide. Parmi les matrices cristallines pouvant accueillir l'ytterbium, les orthosilicates Yb:Y 2SiO5, Yb:Lu2SiO5 et Yb:Sc2SiO 5 se positionnent tres bien, du fait de leur bonne conductivite thermique et du fort eclatement de leur champ cristallin necessaire a l'elaboration de lasers quasi-3 niveaux. De plus l'etude fine et systematique des proprietes microscopiques de nouveaux materiaux s'avere toujours tres interessante du point de vue de la recherche fondamentale, c'est ainsi que de nouveaux modeles sont concus (par exemple pour le champ cristallin) ou que de nouvelles proprietes inhabituelles sont decouvertes, menant a de nouvelles applications. Ainsi d'autres materiaux dopes a l'ytterbium sont connus pour leurs proprietes de couplage electron-phonon, de couplage magnetique, d'emission cooperative ou encore de bistabilite optique, mais ces proprietes n'ont encore jamais ete mises en evidence dans Yb:Y 2SiO5, Yb:Lu2SiO5 et Yb:Sc2SiO 5. Ainsi, cette these a pour but l'etude des proprietes optiques et des interactions microscopiques dans Yb:Y2SiO 5, Yb:Lu2SiO5 et Yb:Sc2SiO5. Nous utilisons principalement les techniques d'absorption IR et de spectroscopie Raman pour determiner les excitations du champ cristallin et les modes de vibration dans le materiau

EVALUATION DE L’IMPACT ENVIRONNEMENTAL : Vers une compréhension de la dynamique des populations de colza « échappées » des cultures à l’échelle d’une région agricole

Directory of Open Access Journals (Sweden)

Pessel Fabrice-Del

2000-07-01

Full Text Available Dans le cadre des études de risques agro-environnementaux, comme dans celui de la mise en place de stratégies de gestion des cultures transgéniques (par exemple la segmentation des filières de production OGM/non OGM, s’il est indispensable de quantifier les différents processus d’échappement des transgènes depuis les parcelles cultivées (flux de pollen et/ou de graines, il est également nécessaire de déterminer leurs potentialités de maintien en dehors des parcelles cultivées (aptitudes écologiques des hybrides interspécifiques et/ou de la plante dans des environnements hors des parcelles cultivées. En effet, des populations, dans lesquelles seraient présents un ou plusieurs transgènes, seraient suceptibles de se comporter comme des réservoirs et/ou des relais de pollutions génétiques entre deux filières de production avec et sans OGM. À plus long terme, la connaissance des processus gouvernant la dynamique et la persistance de ces populations s’avère indispensable pour une gestion efficace des différentes situations de crise possibles (sanitaire, écologique ou agronomique, en particulier pour déterminer la durée des suivis après un arrêt éventuel des cultures transgéniques.

Impacts of Low-Carbon Innovation and Its Heterogeneous Components on CO2 Emissions

Directory of Open Access Journals (Sweden)

Zheming Yan

2017-04-01

Full Text Available This paper aims to investigate the impact of low-carbon innovation on CO2 emissions. Using patent statistics, we measured low-carbon innovations for 15 major economies during the period of 1992–2012. Then, we classified low-carbon technology into clean and gray technology according to the patent classification system. Following the empirical Environmental Kuznets Curve (EKC framework, we explored the effects of low-carbon innovation and its components on CO2 emissions. We did not find any evidence of significant influence of low-carbon innovation. Through further estimations, a significantly negative effect of clean innovation was found while the effect of gray innovation is not clear. Heterogeneous impacts within low-carbon technology provide an explanation for the insignificant impact of low-carbon innovation.

Characterization of volatile organic compounds emissions from municipal landfill and their dispersion in the environment; Caracterisation des emissions de composes organiques volatils issus des centre de stockage de dechets menagers et assimiles et de leur dispersion dans l'environnement

Energy Technology Data Exchange (ETDEWEB)

Chiriac, R.E.

2004-12-15

A municipal landfill causes atmospheric pollution by the emission of trace volatile organic compounds (VOCs) that are harmful for health and environment. Beyond the adsorption technique on sorbent tubes followed by solvent extraction and GC/MS analysis in the laboratory, a pre-concentrator-thermodesorption /micro-gas chromatograph coupling was developed for on-site monitoring of trace VOCs. To evaluate the environmental impact of this traces various studies were realized: 'Study of the emission of VOCs from landfill cells in use', 'Study of the formation of VOCs from a pilot-scale municipal landfill', 'Study of the dispersion of VOCs from a municipal landfill'. All the results permitted a closer appraisal of the emission and dispersion phenomena of VOCs from a municipal landfill. (author)

La cire cuticulaire des grains de raisin et des feuilles de la vigne

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F. RADLER

1968-06-01

Full Text Available Je voudrais parler ici des recherches que j'ai effectuées dans le cadre d'un programme de recherches de l'Organisation australienne de recherches (C.S.I.R.O.. Ce sont des recherches sur la structure, la composition chimique et le rôle de la cire cuticulaire des grains de raisins et des feuilles. Ces recherches ont été effectuées principalement lors de l'étude des problèmes relatifs au séchage des raisins pour la production des raisins. Cependant, l'importance de la cire cuticulaire ne se limite pas seulement au séchage des raisins, car elle concerne aussi l'œnologie et les problèmes de la conservation des raisins de table. Je pense donc que mon exposé peut présenter pour vous un certain intérêt.

Indemnisation des dommages résultant de soins de santé. Phase V : impact budgétaire de la transposition du système français en Belgique

OpenAIRE

Yerna, Benoît-Laurent; Maréchal, Xavier; Denuit, Michel; Closon, Jean-Pierre; Vinck, Imgard

2009-01-01

L’objectif de la présente étude consiste, d’une part, à décrire le système français d’indemnisation des victimes de dommages médicaux et, d’autre part, à calculer l’impact budgétaire de la transposition d’un tel système en Belgique. Les spécificités du système qui sera introduit en Belgique n’étant pas connues au moment de l’étude, le coût a été calculé sur la base des modalités du système en vigueur en France. Les statistiques françaises de fréquences des différents types de dommages (infect...

Impacts of Urban Transportation Mode Split on CO2 Emissions in Jinan, China

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Kebin He

2011-04-01

Full Text Available As the world’s largest developing country, China currently is undergoing rapid urbanization and motorization, which will result in far-reaching impacts on energy and the environment. According to estimates, energy use and carbon emissions in the transportation sector will comprise roughly 30% of total emissions by 2030. Since the late 1990s, transportation-related issues such as energy, consumption, and carbon emissions have become a policy focus in China. To date, most research and policies have centered on vehicle technologies that promote vehicle efficiency and reduced emissions. Limited research exists on the control of greenhouse gases through mode shifts in urban transportation—in particular, through the promotion of public transit. The purpose of this study is to establish a methodology to analyze carbon emissions from the urban transportation sector at the Chinese city level. By using Jinan, the capital of China’s Shandong Province, as an example, we have developed an analytical model to simulate energy consumption and carbon emissions based on the number of trips, the transportation mode split, and the trip distance. This model has enabled us to assess the impacts of the transportation mode split on energy consumption and carbon emissions. Furthermore, this paper reviews a set of methods for data collection, estimation, and processing for situations where statistical data are scarce in China. This paper also describes the simulation of three transportation system development scenarios. The results of this study illustrate that if no policy intervention is implemented for the transportation mode split (the business-as-usual (BAU case, then emissions from Chinese urban transportation systems will quadruple by 2030. However, a dense, mixed land-use pattern, as well as transportation policies that encourage public transportation, would result in the elimination of 1.93 million tons of carbon emissions—approximately 50% of the BAU

Assessing the Climate Impacts of Cookstove Projects: Issues in Emissions Accounting

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Carrie M. Lee

2014-03-01

Full Text Available An estimated 2.6 billion people rely on traditional biomass for home cooking and heating, so improving the efficiency of household cookstoves could provide significant environmental, social and economic benefits. Some researchers have estimated that potential greenhouse gas emission reductions could exceed 1 billion tons of carbon dioxide equivalent (CO2e per year. Carbon finance offers a policy mechanism for realizing some of this potential and could also bring improved monitoring to cookstove projects. However, there are formidable methodological challenges in estimating emission reductions. This paper evaluates the quantification approaches to three key variables in calculating emission impacts: biomass fuel consumption, fraction of non-renewable biomass, and emission factors for fuel consumption. It draws on a literature review as well as on interviews with technical experts and market actors, and identifies lessons learned and knowledge gaps. Key research needs identified include incorporating accounting for uncertainty; development of additional default factors for biomass consumption for baseline stoves; refinement of monitoring approaches for cookstove use; broadened scope of emission factors used for cookstoves; accounting for non-CO2 gases and black carbon; and refinement of estimates and approaches to considering emissions from bioenergy use across methodologies.

statut de la matiere organique des cambisols et des lixisols sous

African Journals Online (AJOL)

Administrateur

L'étude vise à évaluer la matière organique des Cambisols et des Lixisols sous formations naturelles de longue durée en zone climatique nord-soudanienne et à établir, les relations entre ... sont supérieures à celles des sols des zones sahélienne et sud-soudanienne. ... globale a eu une corrélation positive avec le pH.

The economic impact of peste des petits ruminants in India.

Science.gov (United States)

Bardhan, D; Kumar, S; Anandsekaran, G; Chaudhury, J K; Meraj, M; Singh, R K; Verma, M R; Kumar, D; Kumar P T, N; Ahmed Lone, S; Mishra, V; Mohanty, B S; Korade, N; De, U K

2017-04-01

Peste des petits ruminants (PPR) is an economically important livestock disease which affects a vast section of the small ruminant population in India. However, data on the incidence of PPR are limited and scant literature is available on the economic losses caused by the disease. In the present study, a structured sampling design was adopted, which covered the major agro-climatic regions of the country, to ascertain the morbidity and mortality rates of PPR. Available estimates of the economic losses in India due to various livestock diseases are based on single values of various epidemiological and economic parameters. Stochastic modelling was used to estimate the economic impact of PPR. Overall annual morbidity and mortality rates of PPR for small ruminants in India have been estimated from the sample as being 8%and 3.45%, respectively. The authors have analysed variations in these rates across species, age group, sex, season and region. The expected annual economic loss due to PPR in India ranges from as little as US $2 million to $18 million and may go up to US $1.5 billion; the most likely range of expected economic losses is between US $653 million and $669 million. This study thus reveals significant losses due to the incidence of PPR in small ruminants in India.

Fiabilité des structures mécaniques adaptatives: effet de la panne des actionneurs ou des capteurs sur la stabilité

Science.gov (United States)

Fall, H.; Charon, W.; Kouta, R.

2002-12-01

Ces dernières décennies, des activités significatives dans le monde étaient dirigées autour du contrôle actif. Le but de ces recherches était essentiellement d'améliorer les performances, la fiabilité et la sécurité des systèmes. Notamment dans le cas des structures soumises à des vibrations aléatoires. D'importants travaux ont été consacré à l'utilisation des “matériaux intelligents” comme capteurs et actionneurs. Cette article propose l'analyse de la fiabilité des systèmes mécaniques en étudiant les pannes des actionneurs ou des capteurs. L'effet de ces pannes sur la stabilité et la performance du système y est démontré. Les méthodologies de conception y sont rappelées. Des exemples numériques sont fournis à travers le contrôle d'un panneau sous chargement dynamique pour illustrer la méthode proposée.

Évaluation des émissions de gaz à effet de serre des filières de traitement et de valorisation des boues issues du traitement des eaux usées

OpenAIRE

Reverdy, A.L.; Pradel, M.

2011-01-01

/ Ce rapport présente l'inventaire des différentes consommations énergétiques, en consommables et des GES pour chaque poste de traitement et de valorisation des boues issues du traitement des eaux usées.

Investigation of granular impact using positron emission particle tracking

KAUST Repository

Marston, Jeremy O.

2015-04-01

We present results from an experimental study of granular impact using a combination of high-speed video and positron emission particle tracking (PEPT). The PEPT technique exploits the annihilation of photons from positron decay to determine the position of tracer particles either inside a small granular bed or attached to the object which impacts the bed. We use dense spheres as impactors and the granular beds are comprised of glass beads which are fluidised to achieve a range of different initial packing states. For the first time, we have simultaneously investigated both the trajectory of the sphere, the motion of particles in a 3-D granular bed and particles which jump into the resultant jet, which arises from the collapse of the cavity formed by the impacting sphere.

Study of the secondary electron emission during bombardment of metal targets by positive D{sup +} and D{sub 2}{sup +} ions (1960); Etude de l'emission secondaire d'electrons au cours du bombardement de cibles metalliques par des ions positifs D{sup +} et D{sub 2}{sup +} (1960)

Energy Technology Data Exchange (ETDEWEB)

Leroy, J [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Prelec, K [Institut Rudjer Boskovic, Zagreb (Croatia)

1960-07-01

The secondary electron yield {gamma}-bar due to primary positive ions D{sup +} and D{sup +}{sub 2} has been measured in the 70 keV to 300 keV ion energy range. Several metallic targets have been used. The variation of this yield with the angle of incidence is proportional to sec {theta} where {theta} is the angle between the beam of primary ions and the normal to the target surface. The values {gamma}-bar decrease for increasing energy ions. At a given energy all the targets tried gave approximately the same electron yield. (author) [French] Le facteur d'emission secondaire a ete mesure pour des ions positifs D{sup +} et D{sup +}{sub 2} ayant une energie comprise entre 70 keV et 300 keV, sur differentes cibles metalliques. La variation de ce facteur avec l'angle d'incidence suit une loi de la forme {gamma}{sub 0} sec {theta}, {theta} etant l'angle entre le faisceau et la normale a la cible. Les valeurs de {gamma}-bar trouvees decroissent lorsque l'energie des ions incidents augmente, mais sont assez voisines les unes des autres, a une energie donnee, pour les differentes cibles essayees. (auteur)

The climate fund. Some notions on the socio-economic impacts of greenhouse gas emissions and emission reductions in an international context

International Nuclear Information System (INIS)

Tol, R.S.J.; Van der Burg, T.; Jansen, H.M.A.; Verbruggen, H.

1995-05-01

The title project investigates the possibility of setting up an international climate fund and the way in which this could be arranged. A climate fund is a potential method to enhance the efficiency and efficacy of the reduction of the increase in the amount of greenhouse gases (GHGs) in the atmosphere. It would allow countries to transfer capital, for instance through the here proposed climate fund, and to redistribute the damages caused by global warming. This project focuses on the economic aspects of a climate fund, although some attention will also be given to its political feasibility. The system of tradeable emission permits, of which joint implementation is often seen as a pilot phase, presumes that fixed emission targets exist. In this report the emissions are not prefixed, but optimised in a cost-benefit analysis in which the impact of international capital transfer is examined. In order to determine the impact of international capital transfer on the efficiency and efficacy on optimal greenhouse gas emission reduction, three building blocks are needed. The first block concerns the costs of climate change, or the benefits of climate change control. The second block concerns the costs of emission reduction. The third block is the model to integrate costs and benefits, and calculate the optimal emission control with and without international capital transfers. The project is split into four conceptual phases. In the first phase, a literature survey has been performed of the socio-economic costs and benefits of greenhouse gas emission reductions, with a particular focus on the international distribution of costs and benefits. In the second phase, the costs and benefits are modelled in the Climate Framework for Uncertainty, Negotiation and Distribution (FUND). In the third phase the optimal emission reductions are calculated with and without international capital transfers in several game-theoretic settings. (Abstract Truncated)

Le vernis des apparences

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Grazia Nicosia

2010-04-01

Full Text Available Le but de cet article est de comprendre l’incidence sémiotique du nettoyage d’un tableau ainsi que la résultante cognitive induite sur l’observateur. Cette étude confronte l’analyse des phénomènes visuels engendrés par le jaunissement du vernis et son retrait, à des entretiens réalisés à dessein. Le retrait d’un vernis jauni change considérablement l’image. L’heure, le climat, la saison et l’activité même des personnages s’en trouvent ainsi modifié. La patine peut être perçue, soit comme un obstacle à l’exploration, soit pour ceux qui l’apprécient, comme le medium d’une relation plus intime entre l’œuvre et l’observateur.The purpose of this article is to understand the semiotic impact of the cleaning of a painting and the cognitive effects induced on the observer. This study analyses conjointly the visual phenomenon generated by yellowing varnish and its removal and controlled interviews of observers.The removal of yellowing varnish modifies considerably the perception of the picture. Daytime, climate, season and characters activities are modified. The patina may be perceived either as an obstacle to the painting exploration, or, for those who appreciate it, as a medium for a closer relationship between the painting and the observer.

Renforcement de l'autonomie des collectivités au moyen des ...

International Development Research Centre (IDRC) Digital Library (Canada)

Cette subvention permettra au ministère des Communications et des Technologies de l'information de l'Égypte ainsi qu'au fonds spécial réservé aux TI de consolider le modèle actuel des clubs de TI en Égypte, par l'entremise de services d'assistance sur demande, d'activités de formation à l'intention du personnel des ...

L' approche des options stratégiques des acteurs dans i' etude des relations tu travail

OpenAIRE

López Pino, Carmen Marina

2011-01-01

Faire une analyse de la proposition analytique développée par le MIT (Masachussetts Institute of Tecnology) inspirée du concept des options stratégiques pour I' objet de cet article. En premier lieu, les sujets traités seront la problematique des relations du travail et les découvertes fondamentales des différentes recherches de I' equipe du MIT. Après, I' étude fait une courte présentatión sur I' approche des systémes de Dunlop dont I' èquipe cherche améliorer. Ensuite, sont présentés...

Influence des matières végétales et des engrais NPK sur la biologie de Aedes aegypti (Diptera : Culicidae

Directory of Open Access Journals (Sweden)

Darriet F.

2010-06-01

Full Text Available Dans cette étude de laboratoire, les auteurs ont mesuré sur des femelles gravides de Aedes aegypti, l’attractivité à la ponte de milieux aqueux contenant un engrais NPK, de la matière végétale (MV et un mélange composé de MV+NPK. Tandis que les analyses physico-chimiques ont permis d’identifier puis de doser les constituants de chaque milieu, le suivi des larves et la pesée des femelles émergentes nous ont renseigné sur l’impact des composés minéraux et organiques sur le développement des moustiques. Sur les 23 jours qu’a duré l’expérience, la solution NPK est restée aussi attractive que le mélange MV+NPK sans toutefois pouvoir assurer le développement des larves. L’infusion MV a révélé une attractivité à la ponte moins importante, mais elle a apporté aux larves de moustiques les substances organiques dont la solution NPK était dépourvue. Enfin le mélange MV+NPK a attiré les femelles à la ponte tout en assurant pleinement la croissance des larves de Ae. aegypti. Alors que les analyses physico-chimiques de NPK ont révélé une composition essentiellement minérale (NH4++NO3–+P+K et celles de MV de fortes concentrations en carbone et en azote organiques, le mélange MV+NPK s’est distingué par une composition mixte organique et minérale qui a favorisé la prolifération des bactéries et le développement des larves de moustiques. Ce sont des observations importantes qui pourraient aider à la fabrication de pièges à la fois attractifs et létaux (NPK+larvicide et dont les fonctions seraient de piéger les femelles gravides à la recherche d’un lieu de ponte et de tuer les larves à l’éclosion des oeufs.

Assessment of the impact of the European CO2 emissions trading scheme on the Portuguese chemical industry

International Nuclear Information System (INIS)

Tomas, R.A.F.; Ramoa Ribeiro, F.; Santos, V.M.S.; Gomes, J.F.P.; Bordado, J.C.M.

2010-01-01

This paper describes an assessment of the impact of the enforcement of the European carbon dioxide (CO 2 ) emissions trading scheme on the Portuguese chemical industry, based on cost structure, CO 2 emissions, electricity consumption and allocated allowances data from a survey to four Portuguese representative units of the chemical industry sector, and considering scenarios that allow the estimation of increases on both direct and indirect production costs. These estimated cost increases were also compared with similar data from other European Industries, found in the references and with conclusions from simulation studies. Thus, it was possible to ascertain the impact of buying extra CO 2 emission permits, which could be considered as limited. It was also found that this impact is somewhat lower than the impacts for other industrial sectors.

Renforcement des capacités de recherche sur les TIC-D au Moyen ...

International Development Research Centre (IDRC) Digital Library (Canada)

La recherche sur les incidences et les impacts des technologies de l'information et de la communication (TIC) sur le développement social et humain est embryonnaire au Moyen-Orient et en Afrique du Nord (région MOAN). Ce projet vise à encourager les chercheurs de la région MOAN à entreprendre des recherches ...

Impact des changements climatiques sur les écosystèmes alpins : comment les mettre en évidence et les prévoir ?

Directory of Open Access Journals (Sweden)

Nigel G. Yoccoz

2011-01-01

Full Text Available Les écosystèmes alpins vont être grandement influencés par les changements climatiques à venir, mais d’autres facteurs, tels que l’utilisation des terres ou les espèces invasives, pourront aussi jouer un rôle important. Le climat peut influencer les écosystèmes à différents niveaux, et nous en décrivons certains, en mettant l’accent sur les méthodes utilisées et les données disponibles. Le climat peut d’abord modifier la phénologie des espèces, comme la date de floraison des plantes ou la date d’éclosion des insectes. Il peut ensuite affecter directement la démographie des espèces (survie, reproduction, dispersion et donc à terme leur répartition. Il peut enfin agir sur les interactions entre espèces – le couvert neigeux par exemple modifie le succès de certains prédateurs. Une caractéristique des écosystèmes alpins est la présence d’un manteau neigeux important et pourtant l’influence de la neige reste relativement mal connue, en particulier pour des raisons logistiques. Même si nous avons fait des progrès importants dans le développement de modèles prédictifs, surtout pour ce qui est de la répartition des plantes alpines, il reste à mettre en place des réseaux d’observations et d’expériences permettant de mieux tenir compte de la variabilité des écosystèmes alpins et des interactions avec le climat.Alpine ecosystems will be greatly impacted by climatic change, but other factors, such as land use and invasive species, are likely to play an important role too. Climate can influence ecosystems at several levels. We describe some of them, stressing methodological approaches and available data. Climate can modify species phenology, such as flowering date of plants and hatching date in insects. It can also change directly population demography (survival, reproduction, dispersal, and therefore species distribution. Finally it can effect interactions among species –snow cover for example

Modeled Full-Flight Aircraft Emissions Impacts on Air Quality and Their Sensitivity to Grid Resolution

Science.gov (United States)

Vennam, L. P.; Vizuete, W.; Talgo, K.; Omary, M.; Binkowski, F. S.; Xing, J.; Mathur, R.; Arunachalam, S.

2018-01-01

Aviation is a unique anthropogenic source with four-dimensional varying emissions, peaking at cruise altitudes (9–12 km). Aircraft emission budgets in the upper troposphere lower stratosphere region and their potential impacts on upper troposphere and surface air quality are not well understood. Our key objective is to use chemical transport models (with prescribed meteorology) to predict aircraft emissions impacts on the troposphere and surface air quality. We quantified the importance of including full-flight intercontinental emissions and increased horizontal grid resolution. The full-flight aviation emissions in the Northern Hemisphere contributed ~1.3% (mean, min–max: 0.46, 0.3–0.5 ppbv) and 0.2% (0.013, 0.004–0.02 μg/m3) of total O3 and PM2.5 concentrations at the surface, with Europe showing slightly higher impacts (1.9% (O3 0.69, 0.5–0.85 ppbv) and 0.5% (PM2.5 0.03, 0.01–0.05 μg/m3)) than North America (NA) and East Asia. We computed seasonal aviation-attributable mass flux vertical profiles and aviation perturbations along isentropic surfaces to quantify the transport of cruise altitude emissions at the hemispheric scale. The comparison of coarse (108 × 108 km2) and fine (36 × 36 km2) grid resolutions in NA showed ~70 times and ~13 times higher aviation impacts for O3 and PM2.5 in coarser domain. These differences are mainly due to the inability of the coarse resolution simulation to capture nonlinearities in chemical processes near airport locations and other urban areas. Future global studies quantifying aircraft contributions should consider model resolution and perhaps use finer scales near major aviation source regions. PMID:29707471

Modeled Full-Flight Aircraft Emissions Impacts on Air Quality and Their Sensitivity to Grid Resolution

Science.gov (United States)

Vennam, L. P.; Vizuete, W.; Talgo, K.; Omary, M.; Binkowski, F. S.; Xing, J.; Mathur, R.; Arunachalam, S.

2017-12-01

Aviation is a unique anthropogenic source with four-dimensional varying emissions, peaking at cruise altitudes (9-12 km). Aircraft emission budgets in the upper troposphere lower stratosphere region and their potential impacts on upper troposphere and surface air quality are not well understood. Our key objective is to use chemical transport models (with prescribed meteorology) to predict aircraft emissions impacts on the troposphere and surface air quality. We quantified the importance of including full-flight intercontinental emissions and increased horizontal grid resolution. The full-flight aviation emissions in the Northern Hemisphere contributed 1.3% (mean, min-max: 0.46, 0.3-0.5 ppbv) and 0.2% (0.013, 0.004-0.02 μg/m3) of total O3 and PM2.5 concentrations at the surface, with Europe showing slightly higher impacts (1.9% (O3 0.69, 0.5-0.85 ppbv) and 0.5% (PM2.5 0.03, 0.01-0.05 μg/m3)) than North America (NA) and East Asia. We computed seasonal aviation-attributable mass flux vertical profiles and aviation perturbations along isentropic surfaces to quantify the transport of cruise altitude emissions at the hemispheric scale. The comparison of coarse (108 × 108 km2) and fine (36 × 36 km2) grid resolutions in NA showed 70 times and 13 times higher aviation impacts for O3 and PM2.5 in coarser domain. These differences are mainly due to the inability of the coarse resolution simulation to capture nonlinearities in chemical processes near airport locations and other urban areas. Future global studies quantifying aircraft contributions should consider model resolution and perhaps use finer scales near major aviation source regions.

Developpement des betons semi autoplacants a rheologie adaptee pour des infrastructures

Science.gov (United States)

Sotomayor Cruz, Cristian Daniel

Au cours des dernières décennies, les infrastructures canadiennes et québécoises comportent plusieurs structures en béton armé présentant des problèmes de durabilité dus aux conditions climatiques sévères, à la mauvaise conception des structures, à la qualité des matériaux, aux types des bétons choisis, aux systèmes de construction ou à l'existence d'événements incontrôlables. En ce qui concerne le choix du béton pour la construction des infrastructures, une vaste gamme de béton divisée en deux principaux types peut être utilisée: le béton conventionnel vibré (BCV) et le béton autoplaçant (BAP). Dans le cas d'un BCV, la consolidation inadéquate par vibration a été un problème récurrent, occasionnant des dommages structuraux. Ceci a conduit à une réduction de la durabilité et à une augmentation du coût d'entretien et de réparation des infrastructures. Rien que l'utilisation d'un BAP a des avantages tels que l'élimination de la vibration, la réduction des coûts de main d'oeuvre et l'amélioration de la qualité des structures, néanmoins, le coût initial d'un BAP par rapport à un BCV ne permet pas encore de généraliser son utilisation dans l'industrie de la construction. Ce mémoire présente la conception d'une nouvelle gamme de béton semi-autoplaçant pour la construction des infrastructures (BSAP-I) exigeant une vibration minimale. Il s'agit de trouver un équilibre optimal entre la rhéologie et le coût initial du nouveau béton pour conférer une bonne performance structurale et économique aux structures. Le programme expérimental établi a premièrement permis d'évaluer la faisabilité d'utilisation des BSAP-I pour la mise en place des piliers d'une infrastructure de pont à Sherbrooke. En plus, l'utilisation d'un plan d'expériences a permis l'évaluation de trois paramètres de formulation sur les propriétés des mélanges de BSAP-I à l'état frais et durci. Finalement, l'évaluation de la performance des

Libération des acides gras par autolyse enzymatique des triglycérides des graines oléoprotéagineuses

Directory of Open Access Journals (Sweden)

Alibert Gilbert

2001-01-01

Full Text Available Les acides gras produits par hydrolyse chimique des lipides des plantes sont des matériaux de base pour l’industrie des biocarburants, des lubrifiants, des plastiques, des détergents et également des adjuvants de préparations commerciales d’herbicides. Cependant les procédés actuels de production des acides gras sont hautement polluants et coûteux en énergie. Dans ce travail nous développons un nouveau procédé de production des acides gras mettant en œuvre des plantes génétiquement modifiées. Nous avons introduit dans le tabac, retenu comme plante modèle, une construction génétique comprenant un gène de lipase (de la levure Geotrichum candidum sous le contrôle d’un promoteur graine spécifique (promoteur AtEm1 d’Arabidopsis thaliana. Ce promoteur devrait permettre l’expression du gène de lipase au niveau de l’axe embryonnaire tandis que les lipides s’accumulent dans les corps lipidiques des cotylédons. Dans ces conditions, les lipides de la graine devraient être séparés de la lipase par une compartimentation tissulaire et ne pas interférer. Après broyage des graines on peut penser que la mise en contact des lipides et de la lipase conduira à la libération d’acides gras. Plusieurs transformants ont été produits par transfert de gène à l’aide d’Agrobacterium tumefaciens, quelques-uns d’entre eux exprimant, comme attendu, la lipase dans leurs graines. Trois clones (2, 19 et 43 présentent une activité lipase significative et ont été retenus pour des études complémentaires. Cependant l’activité enzymatique observée est faible et certains clones présentent un défaut de compartimentation entre l’enzyme et les lipides se traduisant par la production d’acides gras dans la graine intacte. Lorsque les graines du clone 43 sont broyées dans un tampon, des acides gras sont produits dans le milieu réactionnel, validant le procédé imaginé. De nouvelles constructions réalisées, soit

The impact of temperature and humidity on perception and emission of indoor air pollutants

DEFF Research Database (Denmark)

Fang, Lei; Clausen, Geo; Fanger, Povl Ole

1996-01-01

Sensory response to air polluted by five building materials under different combinations of temperature and humidity in the ranges 18°C-28°C and 30%-70% was studied in the laboratory. The experiments were designed to study separately the impact of temperature and humidity on the perception of air...... polluted by materials, and on the emission of pollutants from the materials. At all tested pollution levels of the five materials, the air was perceived significantly less acceptable with increasing temperature and humidity, and the impact of temperature and humidity on perception decreased with increasing...... pollution level. A significant linear correlation between acceptability and enthalpy of the air was found to describe the influence of temperature and humidity on perception. The impact of temperature and humidity on sensory emission was less significant than the impact on perception; however, the sensory...

Investigations of the Impact of Biodiesel Metal Contaminants on Emissions Control Devices

Energy Technology Data Exchange (ETDEWEB)

Brookshear, D. W.; Lance, M. J.; McCormick, Robert L.; Toops, T. J.

2017-02-27

Biodiesel is a renewable fuel with the potential to displace a portion of petroleum use. However, as with any alternative fuel, in order to be a viable choice it must be compatible with the emissions control devices. The finished biodiesel product can contain up to 5 ppm Na+K and 5 ppm Ca+Mg, and these metal impurities can lead to durability issues with the devices used to control emissions in diesel vehicles. Significant work has been performed to understand how the presence of these metals impacts each individual component of diesel emissions control systems, and this chapter summarizes the findings of these research efforts.

Paternité des articles et intérêts concurrents : une analyse des recommandations aux auteurs des journaux traitant de pratique pharmaceutique

Science.gov (United States)

Courbon, Ève; Tanguay, Cynthia; Lebel, Denis; Bussières, Jean-François

2014-01-01

RÉSUMÉ Contexte : La présence d’auteurs honorifiques et fantômes ainsi que les intérêts concurrents représentent des difficultés bien documentées, liées à la publication d’articles scientifiques. Il existe des lignes directrices encadrant la rédaction et la publication de manuscrits scientifiques, notamment celles de l’International Committee of Medical Journal Editors (ICMJE). Objectifs : L’objectif principal de cette étude descriptive et transversale visait à recenser les instructions portant sur la paternité des articles et les intérêts concurrents provenant des recommandations aux auteurs des journaux traitant de pratique pharmaceutique. L’objectif secondaire visait à déterminer des mesures correctrices pour une paternité des articles plus transparente. Méthode : La recherche a débuté par l’identification des journaux traitant de pratique pharmaceutique. La consultation des instructions aux auteurs des journaux a permis ensuite de recenser les recommandations destinées à éviter les problèmes de paternité des articles et d’intérêts concurrents. Finalement, les membres de l’équipe de recherche se sont consultés afin de définir des mesures correctrices possibles à l’intention des chercheurs. Résultats : Des 232 journaux traitant de pharmacie, 33 ont été définis comme traitant de pratique pharmaceutique. Un total de 24 (73 %) journaux mentionnaient suivre la politique de l’ICMJE, 14 (42 %) demandaient aux auteurs de remplir un formulaire de déclaration d’intérêts concurrents au moment de la soumission de l’article, 17 (52 %) présentaient une définition de la qualité d’auteur et 5 (15 %) demandaient de détailler les contributions de chaque auteur. Une grille de 40 critères a été élaborée pour définir l’attribution du statut d’auteur. Conclusion : Moins de la moitié des journaux demandait aux auteurs de transmettre un formulaire de déclaration des intérêts concurrents au moment de la

The impact of soil amendments on greenhouse gas emissions: a comprehensive life cycle assessment approach

Science.gov (United States)

DeLonge, M. S.; Ryals, R.; Silver, W. L.

2011-12-01

Soil amendments, such as compost and manure, can be applied to grasslands to improve soil conditions and enhance aboveground net primary productivity. Applying such amendments can also lead to soil carbon (C) sequestration and, when materials are diverted from waste streams (e.g., landfills, manure lagoons), can offset greenhouse gas (GHG) emissions. However, amendment production and application is also associated with GHG emissions, and the net impact of these amendments remains unclear. To investigate the potential for soil amendments to reduce net GHG emissions, we developed a comprehensive, field-scale life cycle assessment (LCA) model. The LCA includes GHG (i.e., CO2, CH4, N2O) emissions of soil amendment production, application, and ecosystem response. Emissions avoided by diverting materials from landfills or manure management systems are also considered. We developed the model using field observations from grazed annual grassland in northern California (e.g., soil C; above- and belowground net primary productivity; C:N ratios; trace gas emissions from soils, manure piles, and composting), CENTURY model simulations (e.g., long-term soil C and trace gas emissions from soils under various land management strategies), and literature values (e.g., GHG emissions from transportation, inorganic fertilizer production, composting, and enteric fermentation). The LCA quantifies and contrasts the potential net GHG impacts of applying compost, manure, and commercial inorganic fertilizer to grazing lands. To estimate the LCA uncertainty, sensitivity tests were performed on the most widely ranging or highly uncertain parameters (e.g., compost materials, landfill emissions, manure management system emissions). Finally, our results are scaled-up to assess the feasibility and potential impacts of large-scale adoption of soil amendment application as a land-management strategy in California. Our base case results indicate that C sinks and emissions offsets associated with

Contribution des radios communautaires a l'education des ...

African Journals Online (AJOL)

Contribution des radios communautaires a l'education des populations rurales pour un developpement durable au Benin: etude de cas. ... Journal de la Recherche Scientifique de l'Université de Lomé. Journal Home · ABOUT THIS JOURNAL ...

Rôle des germes parasites des bactéries pathogènes dans l'autoépuration des eaux

Directory of Open Access Journals (Sweden)

GUELIN A.

1969-04-01

Full Text Available Existence dans les eaux polluées de germes parasites qui s'attaquent aux bactéries pathogènes. Le pouvoir bactéricide des eaux polluées dû, en grande partie à la présence dans ces eaux de différents représentants des germes parasites. Possibilité d'application pratique des germes parasites pour l'assainissement des eaux polluées.

Occupational Health and Safety in a Vocational Training Program: How Gender Impacts Teachers' Strategies and Power Relationships: Santé et sécurité des stagiaires dans un programme de formation professionnelle: Impact du genre sur les stratégies et rapports de pouvoir.

Science.gov (United States)

Laberge, Marie; Tondoux, Aurélie; Camiré Tremblay, Fanny; MacEachen, Ellen

2017-11-01

In Quebec (Canada), the Work-Oriented Training Path, a work-study program, prepares students who are having difficulty at school for the job market. Occupational health and safety is an important part of their training. This article aims to analyze the impact of gender on the interpersonal dynamics among teachers, trainees, and key actors from the businesses involved. This article also looks at the influence of gender on teachers' strategies and capacity to act regarding occupational health and safety. Using a work activity analysis lens, a multiple case-study analysis of teachers' work activity was carried out. The findings show that gendered social relationships create a specific supervisory context that influences occupational health and safety training. Solutions aimed at reducing the negative impact of gender-associated prejudice on work injury prevention include training for teachers, attention to work organization at the schools, and the creation of cohesive teachers' work teams. Résumé Au Québec, le Parcours de formation axée sur l'emploi (WOTP), un programme en alternance, offre une préparation au marché du travail aux élèves en difficultés scolaires. La santé et la sécurité du travail (SST) est un enjeu important de la formation. L'article vise à analyser l'impact du genre dans la dynamique relationnelle entre les enseignant.es, leurs élèves et les interlocuteurs clés des entreprises impliquées, et son influence sur les stratégies et la capacité d'agir des enseignant.es en matière de SST. Une analyse de cas multiples basée sur l'analyse ergonomique de l'activité des enseignants a été menée. Les résultats montrent que les relations sociales de genre déterminent un contexte spécifique de supervision qui influence la formation à la SST. La formation des enseignant.es, l'organisation scolaire et la création de collectifs enseignants cohésifs sont des pistes de solution pour réduire l'effet négatif des préjugés liés au genre

Effets des extraits vegetaux sur la dynamique de populations des ...

African Journals Online (AJOL)

La présente étude se propose de trouver une alternative de l'utilisation des pesticides chimiques en testant l'effet insecticide des extraits aqueux des feuilles de Hyptis suaveolens, graines de Ricinus communis et de Azadirachta indica contre les ravageurs du niébé en conditions de champ en utilisant le cyperméthrine ...

Rehabilitation of the natural gas field Thoense with wet transport of natural gas; Sanierung des Erdgasfeldes Thoense unter Anwendung des Erdgasnasstransports

Energy Technology Data Exchange (ETDEWEB)

Neumann, W.; Gerhartz, B.; Schmitt, D.; Uphoff, T. [BEB Erdgas und Erdoel GmbH, Hannover (Germany)

1998-12-31

Natural gas has been extracted the gas field of Thoense situated at the Northern fringe of the city of Hannover for over forty years. At all 10 bore sites the gas was dried with glycol dryers. While dealing with the problem of hydrocarbon emissions from the dryers it became evident, that some of the very old plants had to be rehabilitated. BEB operates the Thoense field on behalf of Elwerath/Brigitta/Deutz. An integrated concept, based on wet transport of natural gas, was used to remove the emission of hydrocarbons and rehabilitate the surface plants in order to cut operating costs. The field at Thoense is now economically efficient enough to continue operations for a long time. [Deutsch] Aus dem am nordoestlichen Stadtrand Hannovers liegenden Gasfeld Thoense wird seit ueber vierzig Jahren Erdgas gefoerdert. Die Gastrocknung erfolgte dort in ueblicher Weise mit Glykoltrocknungsanlagen an allen zehn Bohrungen. Bei der Bearbeitung des damit verbundenen Problems der Kohlenwasserstoffemissionen aus den Trocknungsanlagen wurde der Sanierungsbedarf an den z.T. sehr alten Anlagen deutlich. Das Feld Thoense wird von BEB fuer das Konsortium Elwerath/Brigitta/Deutz betrieben. Es wird gezeigt, wie mit einem integrierten Konzept auf der Basis des Erdgasnasstransportes die KW-Emissionen beseitigt wurden und gleichzeitig eine betriebskostensenkende Sanierung der obertaegigen Anlagen durchgefuehrt werden konnte. Damit wurde die wirtschaftliche Voraussetzung geschaffen, die Gasversorgung aus Thoense noch lange aufrecht erhalten zu koennen. (orig.)

Study of the performances of acoustic emission testing for glass fibre reinforced plastic pipes containing defects; Etude des performances du controle par emission acoustique de tubes en materiaux composites resine-fibre de verre contenant des defauts

Energy Technology Data Exchange (ETDEWEB)

Villard, D.; Vidal, M.C.

1995-08-01

Glass fibre reinforced plastic pipes are more and more often used, in nuclear power plants, for building or replacement of water pipings classified `nuclear safety`. Tests have been performed to evaluate the performances of acoustic emission testing for in service inspection of these components. The tests were focused on glass fibre reinforced polyester and vinyl-ester pipes, in as received conditions or containing impacts, and intentionally introduced defects. They have been carried out by CETIM, following the ASTM Standard E 1118 (code CARP), to a maximum pressure lever of 25 Bar The results show that the CARP procedure can be used for detection of defects and evaluation of their noxiousness towards internal pressure: most of the tubes containing low energy impacts could not be distinguished from tubes without defect; on the other hand the important noxiousness of lacks of impregnation of roving layer appeared clearly. Complementary tests have been performed on some tubes at a more important pressure lever, for which the damage of the tubes in enough to deteriorate there elastic properties. The results showed that CARP procedure give valuable informations on damage level. It would be interesting to evaluate acoustic emission on tubes containing realistic in-service degradations. (author). 11 refs., 15 figs., 6 tabs., 2 appends.

La participation des femmes à la vie politique se traduit par des ...

International Development Research Centre (IDRC) Digital Library (Canada)

La participation des femmes à la vie politique se traduit par des économies locales plus vigoureuses. 08 juin 2016. Image. Des femmes assistent à une réunion d'un groupe d'entraide près d'. Edgard Rodriguez - IDRC. Des femmes assistent à une réunion d'un groupe d'entraide près d'Hyderabad, en Inde. Keenara ...

Incidence des prix et des taxes sur la consommation de produits du ...

International Development Research Centre (IDRC) Digital Library (Canada)

Incidence des prix et des taxes sur la consommation de produits du tabac en Argentine, en Bolivie et au Chili. Partout en Amérique du Sud, les adultes et les enfants font une grande consommation de tabac. Un nouveau projet de recherche se penchera sur les avantages et les limites des stratégies de fixation des prix et de ...

Simulation analysis of emissions trading impact on a non-utility power plant

International Nuclear Information System (INIS)

Imran, Kashif; Ahmad, Intesar; Hassan, Tehzeebul; Aslam, Muhammad Farooq; Ngan, Hon-Wing

2009-01-01

Non-utility power plants can competitively participate in open electricity market to reduce operational costs but in the absence of pollution charges or emissions trading such generators are tempted to cause greater pollution for profit maximization. This paper presents a solution that incorporates pollution charges for nitrogen oxides and sulphur dioxide emissions in line with existing national environmental quality standards and a new carbon dioxide emissions trading mechanism. A novel approach has been used for allocation of allowable emissions that favors efficiently fuelled and environmentally friendly operation for maximizing profit. Impact of proposed carbon trading on economical utilization of enormous indigenous coal reserves has been analyzed and determined to be acceptable. Software developed in this paper, harnessing Sequential Quadratic Programming capabilities of Matlab, is shown to be adequate simulation tool for various emissions trading schemes and an useful operational decision making tool for constrained non-linear optimization problem of a non-utility power plant. (author)

Simulation analysis of emissions trading impact on a non-utility power plant

Energy Technology Data Exchange (ETDEWEB)

Imran, Kashif; Ahmad, Intesar [Department of Electrical Engineering, COMSATS Institute of IT, Lahore (Pakistan); Hassan, Tehzeebul [Department of Electrical Engineering, University of Engineering and Technology (UET), Lahore (Pakistan); Aslam, Muhammad Farooq [Department of Electrical Engineering, University of Management and Technology (UMT), Lahore (Pakistan); Ngan, Hon-Wing [Department of Electrical Engineering, Hong Kong Polytechnic University (China)

2009-12-15

Non-utility power plants can competitively participate in open electricity market to reduce operational costs but in the absence of pollution charges or emissions trading such generators are tempted to cause greater pollution for profit maximization. This paper presents a solution that incorporates pollution charges for nitrogen oxides and sulphur dioxide emissions in line with existing national environmental quality standards and a new carbon dioxide emissions trading mechanism. A novel approach has been used for allocation of allowable emissions that favors efficiently fuelled and environmentally friendly operation for maximizing profit. Impact of proposed carbon trading on economical utilization of enormous indigenous coal reserves has been analyzed and determined to be acceptable. Software developed in this paper, harnessing Sequential Quadratic Programming capabilities of Matlab, is shown to be adequate simulation tool for various emissions trading schemes and an useful operational decision making tool for constrained non-linear optimization problem of a non-utility power plant. (author)

Neutron noise in nuclear reactors; Le bruit neutronique des reacteurs nucleaires

Energy Technology Data Exchange (ETDEWEB)

Blaquiere, A. [Institut National des Sciences et Techniques Nucleaires (France); Pachowska, R. [Universite Technique de Varsovie (Poland)

1961-06-15

The power of a nuclear reactor, in the operating conditions, presents fluctuations due to various causes. This random behaviour can be included in the study of 'noises'. Among other sources of noise, we analyse hereafter the fluctuations due: a) to the discontinuous emissions of neutrons from an independent source; b) to the multiplication of neutrons inside the reactor. The method which we present makes use of the analogies between the rules governing a nuclear reactor in operation and a number of radio-electrical systems, in particular the feed-back loops. The reactor can be characterized by its 'passing band' and is described as a system submitted to a sequence of random pulses. In non linear operating condition, the effect of neutron noise is defined by means of a non-linear functional, this theory is thus related to previous works the references of which are given at the end of the present report. This leads us in particular in the case of nuclear reactors to some results given by A. Blaquiere in the case of radio-electrical loops. (author) [French] La puissance d'un reacteur nucleaire, dans les conditions du regime, est affectee de fluctuations dont les causes sont tres diverses. Ce comportement aleatoire rentre dans le cadre general de l'etude des 'bruits'. Entre autres sources ce bruit, nous analysons ici les fluctuations dues: a) a l'emission discontinue des neutrons provenant d'une source autonome; b) a la multiplication des neutrons au sein du reacteur. La methode que nous introduisons exploite les analogies entre les lois qui regissent un reacteur nucleaire au regime et certains systemes radioelectriques, en particulier les circuits a boucle de reaction. Le reacteur est caracterise par sa 'bande passante' et est decrit comme un systeme soumis a une succession d'impulsions aleatoires. Dans les conditions de fonctionnement non lineaires, l'effet du bruit neutronique est precise en utilisant une fonctionnelle non lineaire, ce qui relie cette theorie a

Economic impact assessment of Turkey's post-Kyoto vision on emission trading

International Nuclear Information System (INIS)

Akın Olçum, Gökçe; Yeldan, Erinç

2013-01-01

For the post-Kyoto period, Turkey strongly emphasizes the establishment of national emission trading system by 2015 and its integration with the EU ETS along its accession process to the EU. In this paper, we study the mechanisms of adjustment and economic welfare consequences of various ETS regimes that Turkey considers to apply by 2020, i.e. regional ETS and international trading within the EU ETS. We conduct our analysis under the current EU 20–20–20 emission target, 20%, and also under its revised version, 30%. We find that Turkey has economic gains from linking with the EU ETS under the 20% cap, in comparison to the domestic ETSs. Despite the EU's welfare loss under linkage in comparison to the case where Turkey has domestic abatement efforts, it still prefers linking as it increases economic well being compared to the case where Turkey does not abate. Under 30% cutback, Turkey has critical output loss under linkage due to high abatement burden on the EU, while the EU is better off as it passes some of its abatement burden to Turkey. Therefore, emission quotas and their allocation across the ETS and non ETS sectors become highly critical in distributing the overall economic gains from bilateral trading. - Highlights: • We conduct welfare analysis of Turkey's post-Kyoto vision on emission trading. • Welfare impacts of having Turkey in the EU ETS via EU accession are analyzed. • Analysis is done with the current EU target of 20%, and the revised target of 30%. • Welfare impacts of linkage on both regions highly depend on the emission targets. • The EU has welfare gains when Turkey engages in abatement actions

Greenhouse Gas and Particulate Emissions and Impacts from Cooking Technologies in Africa

Science.gov (United States)

Kammen, D. M.; Bailis, R.; Kituyi, E.; Ezzati, M.

2003-12-01

In much of Africa, the largest fraction of energy consumption occurs within the residential sector and is derived primarily from woodfuels burned in simple stoves with poor combustion characteristics. Many of the products of incomplete combustion (PICs) are damaging to human health, particularly when they are concentrated in poorly ventilated indoor environments. Incomplete combustion also has potentially harmful impacts on the climate. Prevalent PICs include methane, a potent greenhouse gas (GHG) that is among the pollutants subject to controls under the Kyoto Protocol as well as carbon monoxide (CO), non-methane hydrocarbons (NMHCs) and particulate matter (PM), which can all have an effect on climate, but are not subject to controls under Kyoto. In addition, when woodfuels are used at a rate that reduces standing stocks of trees over the medium or long term, the CO2 released by combustion also has an impact. The choice of stove and fuel technology can have a significant impact on the emission of GHGs as well as on human exposure to health damaging pollutants. In this paper we analyze the emissions of different household energy technologies on a life-cycle basis. We use emission factors to estimate the emissions associated with production, distribution and end-use of common household fuels and assess the likely impacts of these emissions on public health and the global environment. We focus largely on charcoal, a popular fuel in many sub-Saharan African countries. Charcoal is produced by heating wood in the absence of sufficient air for complete combustion to occur. This process removes moisture and most of the volatile compounds. The compounds driven off in the process consist of condensable tars as well as many gaseous hydrocarbons, including ~40 g CH4 per kg of charcoal produced. Combining upstream and end-use emissions, every meal cooked with charcoal has 2-10 times the global warming effect of cooking the same meal with firewood and 5-12 times the effect of

Location matters: The impact of renewable power on transmission congestion and emissions

International Nuclear Information System (INIS)

Hitaj, Claudia

2015-01-01

Many governments offer subsidies for renewable power to reduce greenhouse gas emissions in the power sector. However, most support schemes for renewable power do not take into account that emissions depend on the location of renewable and conventional power plants within an electricity grid. I simulate optimal power flow in a test grid when 4 renewable power plants connect to the grid across 24 potential sites, amounting to over 10,000 configurations. Each configuration is associated with different levels of emissions and renewable power output. I find that emission reductions vary by a factor of 7 and that curtailment due to transmission congestion is more likely when renewable power plants are concentrated in an area of the grid with low demand. Large cost savings could be obtained by allowing subsidies for renewable power to vary across locations according to abatement potential or by replacing subsidies with a price on emissions. - Highlights: • Analyze the impact of renewable power plant location on congestion and emissions. • Simulate optimal power flow in a test grid for over 10,000 configurations. • Determine that emission reductions vary by a factor of 7. • Find that renewable power is curtailed due to transmission congestion. • Pricing emissions is most efficient since abatement potential varies across locations.

Catastrophes et consommation des substances psychoactives

Directory of Open Access Journals (Sweden)

Krivokapić Žilijeta

2009-01-01

Full Text Available (francuski Les catastrophes, les accidents, les stress, les traumatismes sont des expériences négatives de vie accompagnées de changements physiologiques, cognitifs, émotionnels et comportementaux. Les stratégies les plus courantes inefficaces à résoudre les expériences de vie négatives sont: l' agression - ouverte (physique et / ou verbale, passive et latente, le retrait social, le placage, la dépression, l'impuissance, l' isolement et l' abus de médicaments, en particulier de drogues. Les personnes se trouvant dans des situations stressantes essayent de s' aider elles-mêmes souvent en recourant à des substances qui procurent une amélioration de leur état et suppriment le malaise momentané. Cette 'thérapie par auto-thérapie' comporte de graves risques La personne qui, après une période de consommation de ces substances devenaient dépendante, manifeste des changements visibles au niveau physique et psychologique. Elle se dérobe à ses obligations, rompt avec les activités auxquelles elle prenait plaisir autrefois de même qu' avec ses loisirs et ses intérêts; elle change des amis, ses relations familiales et amicales deviennent pauvres et remplies de nombreux conflits; elle devient moins critique et plus manipulative, commence à mentir, trompe pour dissimuler sa toxicomanie, rejoint un groupe de ses semblables, se livre à des activités criminogènes, de plus en plus se dégrade physiquement. L' alcool qui, étant le plus accessible et par conséquent généralement 'la première mesure d' auto-thérapie', a un impact particulièrement dévastateur sur l' organisme sensible au point de vue psycho-physique. Nous assistons à de nombreuses difficultés et des problèmes qui, à la suite de la consommation d' alcool, aggravent ceux liés à des expériences des événements traumatisants. De même l' efficacité de certains comprimés de réduire les tensions ou d' améliorer l' état du patient conduit fréquemment �

Roles et taches des accompagnateurs des patients hospitalises ...

African Journals Online (AJOL)

Roles et taches des accompagnateurs des patients hospitalises dans le service de pneumo-phtysiologie au Centre Hospitalier Universitaire Yalgado Ouedraogo de ... Logistical support represented by material support, drug supply, cleaning of premises, and littering occupied respectively 100%, 91%, 42% and 73%.

35 Contribution à l'étude de l'influence des paramètres d'élaboration ...

African Journals Online (AJOL)

t

l'élaboration du compound et de l'injection-moulage (des granulats issus de ... requires further physico-chemical characterization of raw materials, .... Microscope : Les fractures des échantillons issus de l'essai d'impact ont été observées au.

Climate and Health Impacts of US Emissions Reductions Consistent with 2 C

Science.gov (United States)

Shindell, Drew T.; Lee, Yunha; Faluvegi, Greg

2016-01-01

An emissions trajectory for the US consistent with 2 C warming would require marked societal changes, making it crucial to understand the associated benefits. Previous studies have examined technological potentials and implementation costs and public health benefits have been quantified for less-aggressive potential emissions-reduction policies, but researchers have not yet fully explored the multiple benefits of reductions consistent with 2 C. We examine the impacts of such highly ambitious scenarios for clean energy and vehicles. US transportation emissions reductions avoid approx.0.03 C global warming in 2030 (0.15 C in 2100), whereas energy emissions reductions avoid approx.0.05-0.07 C 2030 warming (approx.0.25 C in 2100). Nationally, however, clean energy policies produce climate disbenefits including warmer summers (although these would be eliminated by the remote effects of similar policies if they were undertaken elsewhere). The policies also greatly reduce damaging ambient particulate matter and ozone. By 2030, clean energy policies could prevent approx.175,000 premature deaths, with approx.22,000 (11,000-96,000; 95% confidence) fewer annually thereafter, whereas clean transportation could prevent approx.120,000 premature deaths and approx.14,000 (9,000-52,000) annually thereafter. Near-term national benefits are valued at approx.US$250 billion (140 billion to 1,050billion) per year, which is likely to exceed implementation costs. Including longer-term, worldwide climate impacts, benefits roughly quintuple, becoming approx.5-10 times larger than estimated implementation costs. Achieving the benefits, however, would require both larger and broader emissions reductions than those in current legislation or regulations.

Standardization in dust emission measurement; Mesure des emissions de poussieres normalisation

Energy Technology Data Exchange (ETDEWEB)

Perret, R. [INERIS, 60 - Verneuil-en-Halatte, (France)

1996-12-31

The European Standardization Committee (CEN TC 264WG5) is developing a new reference method for measuring particulate emissions, suitable for concentrations inferior to 20 mg/m{sup 3} and especially for concentrations around 5 mg/m{sup 3}; the measuring method should be applicable to waste incinerator effluents and more generally to industrial effluents. Testing protocols and data analysis have been examined and repeatability and reproducibility issues are discussed

Impacts économiques et sociaux des changements climatiques sur l ...

International Development Research Centre (IDRC) Digital Library (Canada)

Le projet étudiera l'attribution de l'eau dans les divers secteurs productifs des trois bassins et estimera la demande d'eau pour l'agriculture, l'industrie et la consommation domestique. La recherche identifiera les groupes vulnérables touchés par le stress hydrique engendré par les changements climatiques. On fera appel à ...

Impact of Carbon Quota Allocation Mechanism on Emissions Trading: An Agent-Based Simulation

Directory of Open Access Journals (Sweden)

Wei Jiang

2016-08-01

Full Text Available This paper establishes an agent-based simulation system of the carbon emissions trading in accordance with the complex feature of the trading process. This system analyzes the impact of the carbon quota allocation mechanism on emissions trading for three different aspects including the amount of emissions reduction, the economic effect on the emitters, and the emissions reduction cost. Based on the data of the carbon emissions of different industries in China, several simulations were made. The results indicate that the emissions trading policy can effectively reduce carbon emissions in a perfectly competitive market. Moreover, by comparing separate quota allocation mechanisms, we obtain the result that the scheme with a small extent quota decrease in a comprehensive allocation mechanism can minimize the unit carbon emission cost. Implementing this scheme can also achieve minimal effects of carbon emissions limitation on the economy on the basis that the environment is not destroyed. However, excessive quota decrease cannot promote the emitters to reduce emission. Taking into account that several developing countries have the dual task of limiting carbon emissions and developing the economy, it is necessary to adopt a comprehensive allocation mechanism of the carbon quota and increase the initial proportion of free allocation.

Cell for studying electron-adsorbed gas interactions; Cellule d'etudes des interactions electron-gaz adsorbe

Energy Technology Data Exchange (ETDEWEB)

Golowacz, H; Degras, D A [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires, Deptartement de Physique des Plasmas et de la Fusion Controlee, Service de Physique Appliquee, Service de Physique des Interractions Electroniques, Section d' Etude des Interactions Gaz-Solides

1967-07-01

The geometry and the technology of a cell used for investigations on electron-adsorbed gas interactions are described. The resonance frequencies of the surface ions which are created by the electron impact on the adsorbed gas are predicted by simplified calculations. The experimental data relative to carbon monoxide and neon are in good agreement with these predictions. (authors) [French] Les caracteristiques geometriques et technologiques generales d'une cellule d'etude des interactions entre un faisceau d'electrons et un gaz adsorbe sont donnees. Un calcul simplifie permet de prevoir les frequences de resonance des ions de surface crees par l'impact des electrons sur le gaz adsorbe. Les donnees experimentales sur l'oxyde de carbone et le neon confirment les previsions du calcul. (auteurs)

Investissement à impact social: augmenter l'investissement du ...

International Development Research Centre (IDRC) Digital Library (Canada)

Les investisseurs privés et les organismes philanthropiques investissent de plus en plus dans des organisations et des entreprises sociales qui fournissent des biens et des services prisés par la société. La portée du marché des investissements à impact social est désormais mondiale, et elle s'étend rapidement dans ...

Utilisation des mousses et des pâtes syntactiques pour combler les lacunes des poteries archéologiques

Directory of Open Access Journals (Sweden)

Viviane Bechoux

2008-10-01

Full Text Available Filling potteries missing parts with plaster raises now complex problems during the de-restoration treatments. Ceramics restorers have recurrently questions on the use of plaster in the field of archaeological ceramics restoration. Some researches point to the choice of other filling materials. At the present time other methods can be devised by proposing plaster replacement by a lightened composite material: syntactic foams and pastes.Le comblement des lacunes des poteries à partir du plâtre pose actuellement des problèmes complexes lors des traitements de dérestauration. Les restaurateurs de céramiques s'interrogent de manière récurrente sur l'utilisation du plâtre dans le domaine de la restauration des céramiques archéologiques. Des recherches s'orientent vers le choix d'autres matériaux d'obturation. Actuellement, d'autres méthodes peuvent être mises en place en proposant le remplacement du plâtre par un matériau composite allégé, les mousses et les pâtes syntactiques.

Développer le leadership dans des villes de l'Amérique latine et des ...

International Development Research Centre (IDRC) Digital Library (Canada)

Développer le leadership dans des villes de l'Amérique latine et des Caraïbes dans le contexte des changements climatiques. En raison des changements climatiques, de la croissance démographique et de l'urbanisation rapide non planifiée, les villes des pays en développement sont à la fois le principal déclencheur des ...

La Question de L'impunité des Auteurs de Violations des Droits de L'homme

Directory of Open Access Journals (Sweden)

Maria dos Remédios Fontes Silva

2010-10-01

Full Text Available Ce travail pretend faire reflechir à propos de la question de l'impunite des autorites de L'Etat face aux violations des droits de l'homme. On abordera cet egard: a le role de I'amnistie ble complicite des autoritesadministratives c la lenteur des procedures judicieuse.     L'analyse de cette question montre qui L'impunite des responsables des violations des droits de l'homme fait peser une menace sur I'ensemble du systeme de protection universelle des droits de l'homme.          On peut on conduire qu 'aucune societe que aspire à la democratie et ala justice ne peut se construire sur I'amoralite des crimes impunis et I'amnesie officielle.

Etude aerodynamique d'un jet turbulent impactant une paroi concave

Science.gov (United States)

LeBlanc, Benoit

Etant donne la demande croissante de temperatures elevees dans des chambres de combustion de systemes de propulsions en aerospatiale (turbomoteurs, moteur a reaction, etc.), l'interet dans le refroidissement par jets impactant s'est vu croitre. Le refroidissement des aubes de turbine permet une augmentation de temperature de combustion, ce qui se traduit en une augmentation de l'efficacite de combustion et donc une meilleure economie de carburant. Le transfert de chaleur dans les au bages est influence par les aspects aerodynamiques du refroidissement a jet, particulierement dans le cas d'ecoulements turbulents. Un manque de comprehension de l'aerodynamique a l'interieur de ces espaces confinees peut mener a des changements de transfert thermique qui sont inattendus, ce qui augmente le risque de fluage. Il est donc d'interet pour l'industrie aerospatiale et l'academie de poursuivre la recherche dans l'aerodynamique des jets turbulents impactant les parois courbes. Les jets impactant les surfaces courbes ont deja fait l'objet de nombreuses etudes. Par contre des conditions oscillatoires observees en laboratoire se sont averees difficiles a reproduire en numerique, puisque les structures d'ecoulements impactants des parois concaves sont fortement dependantes de la turbulence et des effets instationnaires. Une etude experimentale fut realisee a l'institut PPRIME a l'Universite de Poitiers afin d'observer le phenomene d'oscillation dans le jet. Une serie d'essais ont verifie les conditions d'ecoulement laminaires et turbulentes, toutefois le cout des essais experimentaux a seulement permis d'avoir un apercu du phenomene global. Une deuxieme serie d'essais fut realisee numeriquement a l'Universite de Moncton avec l'outil OpenFOAM pour des conditions d'ecoulement laminaire et bidimensionnel. Cette etude a donc comme but de poursuivre l'enquete de l'aerodynamique oscillatoire des jets impactant des parois courbes, mais pour un regime d'ecoulement transitoire, turbulent

Membrane fluidization by alcohols inhibits DesK-DesR signalling in Bacillus subtilis.

Science.gov (United States)

Vaňousová, Kateřina; Beranová, Jana; Fišer, Radovan; Jemioła-Rzemińska, Malgorzata; Matyska Lišková, Petra; Cybulski, Larisa; Strzałka, Kazimierz; Konopásek, Ivo

2018-03-01

After cold shock, the Bacillus subtilis desaturase Des introduces double bonds into the fatty acids of existing membrane phospholipids. The synthesis of Des is regulated exclusively by the two-component system DesK/DesR; DesK serves as a sensor of the state of the membrane and triggers Des synthesis after a decrease in membrane fluidity. The aim of our work is to investigate the biophysical changes in the membrane that are able to affect the DesK signalling state. Using linear alcohols (ethanol, propanol, butanol, hexanol, octanol) and benzyl alcohol, we were able to suppress Des synthesis after a temperature downshift. The changes in the biophysical properties of the membrane caused by alcohol addition were followed using membrane fluorescent probes and differential scanning calorimetry. We found that the membrane fluidization induced by alcohols was reflected in an increased hydration at the lipid-water interface. This is associated with a decrease in DesK activity. The addition of alcohol mimics a temperature increase, which can be measured isothermically by fluorescence anisotropy. The effect of alcohols on the membrane periphery is in line with the concept of the mechanism by which two hydrophilic motifs located at opposite ends of the transmembrane region of DesK, which work as a molecular caliper, sense temperature-dependent variations in membrane properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact du comportement vibratoire et acoustique des joints de portes et de vitrages sur le bruit d'origine aérodynamique

OpenAIRE

Oliver , Clara; Jézéquel , Louis; Besset , Sébastien; VAN HERPE , François; Abbadi , Zouhir

2015-01-01

International audience; Dans la modélisation des joints de portes et de vitrages pour la prédiction du bruit aérodynamique il est nécessaire de sortir du domaine classique du calcul vibro-acoustique linéaire, en raison du caractère fortement non-linéaire des joints. La déformation lors de la fermeture des portes ou vitres provoque des modifications des raideurs statique et dynamique, de l'amortissement et de la transparence acoustique des joints. Ensuite les efforts aérodynamiques modifient c...

Global volcanic emissions: budgets, plume chemistry and impacts

Science.gov (United States)

Mather, T. A.

2012-12-01

Over the past few decades our understanding of global volcanic degassing budgets, plume chemistry and the impacts of volcanic emissions on our atmosphere and environment has been revolutionized. Global volcanic emissions budgets are needed if we are to make effective use of regional and global atmospheric models in order to understand the consequences of volcanic degassing on global environmental evolution. Traditionally volcanic SO2 budgets have been the best constrained but recent efforts have seen improvements in the quantification of the budgets of other environmentally important chemical species such as CO2, the halogens (including Br and I) and trace metals (including measurements relevant to trace metal atmospheric lifetimes and bioavailability). Recent measurements of reactive trace gas species in volcanic plumes have offered intriguing hints at the chemistry occurring in the hot environment at volcanic vents and during electrical discharges in ash-rich volcanic plumes. These reactive trace species have important consequences for gas plume chemistry and impacts, for example, in terms of the global fixed nitrogen budget, volcanically induced ozone destruction and particle fluxes to the atmosphere. Volcanically initiated atmospheric chemistry was likely to have been particularly important before biological (and latterly anthropogenic) processes started to dominate many geochemical cycles, with important consequences in terms of the evolution of the nitrogen cycle and the role of particles in modulating the Earth's climate. There are still many challenges and open questions to be addressed in this fascinating area of science.

Photonique des Morphos

CERN Document Server

Berthier, Serge

2010-01-01

La photonique est déjà présente dans notre vie quotidienne, et on attend maintenant que la manipulation des photons permette aussi le traitement logique des informations. Cependant, l’élément de base qui permet cette manipulation de la lumière, le cristal photonique, est d’une réalisation complexe et mal contrôlée. Dans la course à la maîtrise de la lumière, les structures photoniques naturelles ont beaucoup à nous apprendre. C’est ce que nous montre Serge Berthier qui étudie dans ce livre la structure des écailles des Morphos. Tenant compte de l’essor récent des approches biomimétiques, il présente de manière détaillée plus de dix-huit techniques expérimentales utilisées pour ses analyses, ainsi que les diverses approches théoriques développées pour la modélisation de structures multi-échelles complexes. Première étude quasi-exhaustive des structures fines d’un genre et des propriétés optiques ainsi que colorimétriques générées, ce livre fournit aux entomologiste...

Dissociative Excitation of Acetylene Induced by Electron Impact: Excitation-emission Cross-sections

Energy Technology Data Exchange (ETDEWEB)

Országh, Juraj; Danko, Marián; Čechvala, Peter; Matejčík, Štefan, E-mail: matejcik@fmph.uniba.sk [Department of Experimental Physics, Faculty of Mathematics, Physics and Informatics, Comenius University in Bratislava, Mlynská dolina F-2, 842 48 Bratislava (Slovakia)

2017-05-20

The optical emission spectrum of acetylene excited by monoenergetic electrons was studied in the range of 190–660 nm. The dissociative excitation and dissociative ionization associated with excitation of the ions initiated by electron impact were dominant processes contributing to the spectrum. The spectrum was dominated by the atomic lines (hydrogen Balmer series, carbon) and molecular bands (CH(A–X), CH(B–X), CH{sup +}(B–A), and C{sub 2}). Besides the discrete transitions, we have detected the continuum emission radiation of ethynyl radical C{sub 2}H(A–X). For most important lines and bands of the spectrum we have measured absolute excitation-emission cross sections and determined the energy thresholds of the particular dissociative channels.

Screening phytochimique et identification spectroscopique des ...

African Journals Online (AJOL)

Origin

plante, effectuée pour la première fois, a révélé la présence des alcaloïdes, des flavonoïdes, des tanins catéchiques, des terpènes, des coumarines et des composés cyanogénétiques. Quant aux saponines et les quinones libres, ils sont présents chez les fleurs et absents chez les feuilles. La caractérisation des molécules.

The relative importance of impacts from climate change vs. emissions change on air pollution levels in the 21st century

Directory of Open Access Journals (Sweden)

G. B. Hedegaard

2013-04-01

Full Text Available So far several studies have analysed the impacts of climate change on future air pollution levels. Significant changes due to impacts of climate change have been made clear. Nevertheless, these changes are not yet included in national, regional or global air pollution reduction strategies. The changes in future air pollution levels are caused by both impacts from climate change and anthropogenic emission changes, the importance of which needs to be quantified and compared. In this study we use the Danish Eulerian Hemispheric Model (DEHM driven by meteorological input data from the coupled Atmosphere-Ocean General Circulation Model ECHAM5/MPI-OM and forced with the newly developed RCP4.5 emissions. The relative importance of the climate signal and the signal from changes in anthropogenic emissions on the future ozone, black carbon (BC, total particulate matter with a diameter below 2.5 μm (total PM2.5 including BC, primary organic carbon (OC, mineral dust and secondary inorganic aerosols (SIA and total nitrogen (including NHx + NOy has been determined. For ozone, the impacts of anthropogenic emissions dominate, though a climate penalty is found in the Arctic region and northwestern Europe, where the signal from climate change dampens the effect from the projected emission reductions of anthropogenic ozone precursors. The investigated particles are even more dominated by the impacts from emission changes. For black carbon the emission signal dominates slightly at high latitudes, with an increase up to an order of magnitude larger, close to the emission sources in temperate and subtropical areas. Including all particulate matter with a diameter below 2.5 μm (total PM2.5 enhances the dominance from emissions change. In contrast, total nitrogen (NHx + NOy in parts of the Arctic and at low latitudes is dominated by impacts of climate change.

Assessing Development Impacts Associated with Low Emission Development Strategies: Lessons Learned from Pilot Efforts in Kenya and Montenegro

Energy Technology Data Exchange (ETDEWEB)

Cox, S. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Katz, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wurtenberger, L. [Energy Research Centre of the Netherlands (ECN), Petten (Netherlands)

2014-01-01

Low emission development strategies (LEDS) articulate economy-wide policies and implementation plans designed to enable a country to meet its long-term development objectives while reducing greenhouse gas emissions. A development impact assessment tool was developed to inform an analytically robust and transparent prioritization of LEDS actions based on their economic, social, and environmental impacts. The graphical tool helps policymakers communicate the development impacts of LEDS options and identify actions that help meet both emissions reduction and development goals. This paper summarizes the adaptation and piloting of the tool in Kenya and Montenegro. The paper highlights strengths of the tool and discusses key needs for improving it.

Characterization of in-use light-duty gasoline vehicle emissions by remote sensing in Beijing: impact of recent control measures.

Science.gov (United States)

Zhou, Yu; Fu, Lixin; Cheng, Linglin

2007-09-01

China's national government and Beijing city authorities have adopted additional control measures to reduce the negative impact of vehicle emissions on Beijing's air quality. An evaluation of the effectiveness of these measures may provide guidance for future vehicle emission control strategy development. In-use emissions from light-duty gasoline vehicles (LDGVs) were investigated at five sites in Beijing with remote sensing instrumentation. Distance-based mass emission factors were derived with fuel consumption modeled on real world data. The results show that the recently implemented aggressive control strategies are significantly reducing the emissions of on-road vehicles. Older vehicles are contributing substantially to the total fleet emissions. An earlier program to retrofit pre-Euro cars with three-way catalysts produced little emission reduction. The impact of model year and driving conditions on the average mass emission factors indicates that the durability of vehicles emission controls may be inadequate in Beijing.

L'accumulation des métaux lourds au niveau des cultures : Cas des ...

African Journals Online (AJOL)

Le Bassin de Sebou présente une importance socio-économique pour le Maroc. En effet, il est sujet de diverses utilisations ; eau potable, eau d'irrigation et eau industrielle. Toutefois, ce bassin subit des pressions multiples, notamment par la pollution métallique. Considérant le risque de bioaccumulation des métaux par ...

Ion emission from micrometeorite impacts on atmosphereless planets

International Nuclear Information System (INIS)

Wekhof, A.

1980-01-01

Conclusions have been drawn on the generation of intensive high-velocity ions and atoms fluxes on the surfaces of the Moon, Mercury and the atmosphereless satellites of Jupiter by micrometeorite impacts. About 30% of each flux is ejected at small angles and detained by planetary reliefs, forming surface-active layer of alkalines. The combined erosional effect of that layer, the thermocycling and the radiational tracks have been studied. The ion fluxes leaving Jupiter's atmosphereless satellites may well be one of the main sources of the short UV-emission in their vicinities. (Auth.)

The global impact of the transport sectors on atmospheric aerosol: simulations for year 2000 emissions

Directory of Open Access Journals (Sweden)

M. Righi

2013-10-01

Full Text Available We use the EMAC (ECHAM/MESSy Atmospheric Chemistry global model with the aerosol module MADE (Modal Aerosol Dynamics model for Europe, adapted for global applications to quantify the impact of transport emissions (land transport, shipping and aviation on the global aerosol. We consider a present-day (2000 scenario according to the CMIP5 (Climate Model Intercomparison Project Phase 5 emission data set developed in support of the IPCC (Intergovernmental Panel on Climate Change Fifth Assessment Report. The model takes into account particle mass and number emissions: The latter are derived from mass emissions under different assumptions on the size distribution of particles emitted by the three transport sectors. Additional sensitivity experiments are performed to quantify the effects of the uncertainties behind such assumptions. The model simulations show that the impact of the transport sectors closely matches the emission patterns. Land transport is the most important source of black carbon (BC pollution in the USA, Europe and the Arabian Peninsula, contributing up to 60–70% of the total surface-level BC concentration in these regions. Shipping contributes about 40–60% of the total aerosol sulfate surface-level concentration along the most-traveled routes of the northern Atlantic and northern Pacific oceans, with a significant impact (~ 10–20% along the coastlines. Aviation mostly affects aerosol number, contributing about 30–40% of the particle number concentration in the northern midlatitudes' upper troposphere (7–12 km, although significant effects are also simulated at the ground, due to the emissions from landing and take-off cycles. The transport-induced perturbations to the particle number concentrations are very sensitive to the assumptions on the size distribution of emitted particles, with the largest uncertainties (about one order of magnitude obtained for the land transport sector. The simulated climate impacts, due to

Modelling the impact of EVs on electricity generation, costs and CO2 emissions

International Nuclear Information System (INIS)

Calnan, P.; Deane, J.P.; Ó Gallachóir, B.P.

2013-01-01

This paper focuses on the impact of electric vehicles on electricity generation in Ireland in 2025 based on five alternative generation portfolios. The year 2025 was selected for assessment due to the information on the composition of the five generation portfolios from Eirgrid the system operator in Ireland being provided. Detailed market simulations were undertaken on the five possible generation portfolios to assess the impact of the Government targets for electric vehicles on the generation costs, emissions, generation stack and the cost to load of this additional demand. This paper also studied the impact between a standard and least cost electric vehicle loading regime to ascertain the benefits that could be achieved. The results show that gas will be the dominant source of electricity generation to load electric vehicles and that wind as an electricity source will experience a minor reduction in curtailment, with the least cost charging profile showing a more pronounced reduction. The capital benefits of the Standard and Least Cost EV load are found to be negligible. The portfolios studied generated CO 2 emissions per kilometre between 52 and 70 gCO 2 /km. All portfolios with the exception of coal were found to comply with EU regulation 443/2009. - Highlights: • This paper focuses on the impact of electric vehicles on electricity generation in Ireland in 2025. • It uses the PLEXOS software package by Energy Exemplar to model the Irish electricity market. • Government targets for electric vehicle penetration have a limited impact on the power system. • Electric vehicles will meet EU requirements in terms of emissions created per kilometre

Estimating biogenic contributions to secondary pollutants: formation at regional scale (Fosse Rhenan, France); Impact des emissions naturelles sur les episodes de pollution photochimique: application a la region du Fosse Rhenan

Energy Technology Data Exchange (ETDEWEB)

Moukhtar, S.

2005-02-15

Biotic volatile organic compounds (VOCs) play a significant role in the formation and development of photochemical pollution events. In this context, the integration of biotic VOCs in the CHIMERE chemical transport model has been improved by the use of a double numerical and experimental approach. Field measurements have permitted to determine the flux of emissions of biotic VOCs from three tree species particularly abundant in France: Abies alba, Fagus sylvatica and Pseudotsuga menziesii. A database has been updated and used to estimate the annual VOC emissions by the French forestry system. A critical synthesis of the bibliography about the reactivity of biotic VOCs has led to the elaboration of a new chemical mechanism which has been implemented in the CHIMERE model. The results of this model have been compared to the observations available for the region of the Rhine through (Fosse Rhenan) characterized by strong biotic VOC emissions. These modifications does not change much the ozone concentrations but they have strong impacts on the modeling of peroxy-acetyl-nitrate (PAN) and formaldehyde concentrations. (J.S.)

The impact of lifestyle on energy use and CO2 emission: An empirical analysis of China's residents

International Nuclear Information System (INIS)

Wei, Y.-M.; Liu, L.-C.; Fan Ying; Wu Gang

2007-01-01

Based on the application of a Consumer Lifestyle Approach (CLA), this paper quantifies the direct and indirect impact of lifestyle of urban and rural residents on China's energy use and the related CO 2 emissions during the period 1999-2002. The results show that approximately 26 per cent of total energy consumption and 30 per cent of CO 2 emission every year are a consequence of residents' lifestyles, and the economic activities to support these demands. For urban residents the indirect impact on energy consumption is 2.44 times greater than the direct impact. Residence; home energy use; food; and education, cultural and recreation services are the most energy-intensive and carbon-emission-intensive activities. For rural residents, the direct impact on energy consumption is 1.86 times that of the indirect, and home energy use; food; education, and cultural recreation services; and personal travel are the most energy-intensive and carbon-emission-intensive activities. This paper provides quantitative evidence for energy conservation and environmental protection focused policies. China's security for energy supply is singled out as a serious issue for government policy-makers, and we suggest that government should harmonize the relationships between stakeholders to determine rational strategies

Contrôle des Circuits Auxiliaires des PFW (arrêt machines 2002/2003)

CERN Document Server

Ottaviani, J

2003-01-01

Les PFW sont des nappes polaires installées sur les pôles des aimants du PS. Elles sont au nombre de 4 par unité d aimant et constituées d un circuit principal (dans lequel circule le courant désiré selon le cycle magnétique utilisé) et de circuits auxiliaires. Les circuits auxiliaires sont des enroulements de correction (boucles de tour et pick-up brasés sur les enroulements). Pendant la variation du champ magnétique de l aimant PS, on utilise des tensions induites dans ces circuits auxiliaires pour corriger les erreurs de champ dues aux courants de Foucault dans la chambre à vide. Chaque année, pendant l arrêt machine, on vérifie si les caractéristiques des circuits auxiliaires correspondent aux normes (mesures des résistances des boucles de tours, résistances entre pick-up et isolation des circuits) afin de faire un suivi. Les 404 PFW sont ainsi vérifiées. Dans cette note, on ne relèvera que les PFW ayant des défauts (valeurs hors tolérances, boucles ouvertes ou en court-circuit, déf...

Assessment of the impact of the European CO{sub 2} emissions trading scheme on the Portuguese chemical industry

Energy Technology Data Exchange (ETDEWEB)

Tomas, R.A.F. [Artenius Sines, Zona Industrial, 7520 Sines (Portugal); Ramoa Ribeiro, F.; Bordado, J.C.M. [Centro de Engenharia Quimica e Biologica, IBB-Instituto de Biotecnologia e Bioengenharia, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Santos, V.M.S. [Instituto Superior de Economia e Gestao, R. do Quelhas, 6, 1200-781 Lisboa (Portugal); Gomes, J.F.P. [Centro de Engenharia Quimica e Biologica, IBB-Instituto de Biotecnologia e Bioengenharia, Instituto Superior Tecnico, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Departamento de Engenharia Quimica, Instituto Superior de Engenharia de Lisboa, R. Conselheiro Emidio Navarro 1949-014 Lisboa (Portugal)

2010-01-15

This paper describes an assessment of the impact of the enforcement of the European carbon dioxide (CO{sub 2}) emissions trading scheme on the Portuguese chemical industry, based on cost structure, CO{sub 2} emissions, electricity consumption and allocated allowances data from a survey to four Portuguese representative units of the chemical industry sector, and considering scenarios that allow the estimation of increases on both direct and indirect production costs. These estimated cost increases were also compared with similar data from other European Industries, found in the references and with conclusions from simulation studies. Thus, it was possible to ascertain the impact of buying extra CO{sub 2} emission permits, which could be considered as limited. It was also found that this impact is somewhat lower than the impacts for other industrial sectors. (author)

Nitrous Oxide Formation and Destruction by Industrial No Abatement Techniques Including Scr Emissions des protoxides d'azote par des techniques industrielles d'abattement de NO y compris le SCR

Directory of Open Access Journals (Sweden)

De Soete G. G.

2006-11-01

Full Text Available Systematic investigations on N2O emission from full scale stationary combustion units, equipped with primary or secondary NO control techniques, are scarce or inexistent. Recent results obtained from laboratory scale studies are presented, from which it appears that fuel staging, selective non catalytic NO reduction with ammonia and selective catalytic NO reduction in the presence of ammonia, should be considered as potential sources of nitrous oxide emission enhancement. For the two mentioned gas phase NO abatement techniques (fuel staging and NCSR, this N2O emission enhancement is clearly linked with a decrease of the temperature, a result that might have been expected from the known gas phase reactions of N2O formation and destruction. Production of N2O from NCSR is more important than from fuel staging, and increases with ammonia concentration; this probably is related to the fact that ammonia yields N2O precursors (NH, NH2 readily by its decomposition. Separate injection of pure NO or NH3 suggests that N2O is a product of the interaction of those two reactants, whereas NO also is formed as a primary ammonia decomposition product in the presence of oxygen. A kinetic investigation of N2O formation from SCR has been made. It is shown that catalytic decomposition of neat ammonia yields both NO and N2O, the former as a primary product (from adsorbed ammonia and solid bound oxygen, the latter as a secondary product (from NO and adsorbed ammonia. Both NO and N2O subsequently undergo catalytic decomposition. In the presence of molecular oxygen, another NO formation (from O2 and adsorbed ammonia manifests itself at somewhat higher temperatures, creating the well known optimum temperature window . Comparative tests conducted on a number of metal oxides, tend to show that high efficiency for NO decomposition is often related to high production of N2O within the temperature window . On ne dispose actuellement pas encore de résultats d

Gestion des risques, valorisation et stratégie : applications aux industries agro-alimentaire et de transport aérien

OpenAIRE

Hassane Amadou, Rahila

2014-01-01

Ce travail de recherche apporte des éléments de compréhension supplémentaires sur l’impact des stratégies de gestion des risques sur la valeur et sur la stratégie des entreprises. Une première analyse examine un échantillon de 378 observations d’entreprises du secteur agroalimentaire sur 5 ans. Il ressort de cette analyse que l’intensité d’utilisation des produits dérivés pour couvrir les risques de change, taux d’intérêt et prix des matières premières n’influence pas sensiblement la valeur d...

Impact of policy on greenhouse gas emissions and economics of biodiesel production.

Science.gov (United States)

Olivetti, Elsa; Gülşen, Ece; Malça, João; Castanheira, Erica; Freire, Fausto; Dias, Luis; Kirchain, Randolph

2014-07-01

As an alternative transportation fuel to petrodiesel, biodiesel has been promoted within national energy portfolio targets across the world. Early estimations of low lifecycle greenhouse gas (GHG) emissions of biodiesel were a driver behind extensive government support in the form of financial incentives for the industry. However, studies consistently report a high degree of uncertainty in these emissions estimates, raising questions concerning the carbon benefits of biodiesel. Furthermore, the implications of feedstock blending on GHG emissions uncertainty have not been explicitly addressed despite broad practice by the industry to meet fuel quality standards and to control costs. This work investigated the impact of feedstock blending on the characteristics of biodiesel by using a chance-constrained (CC) blend optimization method. The objective of the optimization is minimization of feedstock costs subject to fuel standards and emissions constraints. Results indicate that blending can be used to manage GHG emissions uncertainty characteristics of biodiesel, and to achieve cost reductions through feedstock diversification. Simulations suggest that emissions control policies that restrict the use of certain feedstocks based on their GHG estimates overlook blending practices and benefits, increasing the cost of biodiesel. In contrast, emissions control policies which recognize the multifeedstock nature of biodiesel provide producers with feedstock selection flexibility, enabling them to manage their blend portfolios cost effectively, potentially without compromising fuel quality or emissions reductions.

Impact of H{sub 2} emissions of a global hydrogen economy on the stratosphere

Energy Technology Data Exchange (ETDEWEB)

Grooss, Jens-Uwe; Feck, Thomas; Vogel, Baerbel; Riese, Martin [Forschungszentrum Juelich (Germany)

2010-07-01

''Green'' hydrogen is seen as a major element of the future energy supply to reduce greenhouse gas emissions substantially. However, due to the possible interactions of hydrogen (H{sub 2}) with other atmospheric constituents there is a need to analyse the implications of additional atmospheric H{sub 2} that could result from hydrogen leakage of a global hydrogen infrastructure. Emissions of molecular H{sub 2} can occur along the whole hydrogen process chain which increase the tropospheric H{sub 2} burden. The impact of these emissions is investigated. Figure 1 is a sketch that clarifies the path way and impact of hydrogen in the stratosphere. The air follows the Brewer-Dobson circulation in which air enters the stratosphere through the tropical tropopause, ascends then to the upper stratosphere and finally descends in polar latitudes within a typical transport time frame of 4 to 8 years. (orig.)

Contribution des TICs à l'abandon des mutilations génitales ...

International Development Research Centre (IDRC) Digital Library (Canada)

Contribution des TIC à l'abandon des MGF en Afrique de l'Ouest francophone : rôle des jeunes citoyennes; rapport technique no. 5 (rapport technique final), 18 octobre 2008 - 31 mars 2009. Download PDF. Related content. New website will help record vital life events to improve access to services for all. A new website ...

utilisation des donnees pour l'evaluation de l'heterogeneite des sols

African Journals Online (AJOL)

AISA

étude a permis de caractériser l'hétérogénéité des sols ferrallitiques, à travers sa couleur. Mots-clés : Couleur ... ainsi qu'à l'application des recommandations des doses de fertilisant. ..... de « système sol » en zone de contact forêt- savane du ...

Reduction of CO2 emissions from road transport in cities impact of dynamic route guidance system on greenhouse gas emission

CERN Document Server

Markiewicz, Michal

2017-01-01

Michal Markiewicz presents the outcomes of his research regarding the influence of dynamic route guidance system on overall emission of carbon dioxide from road transport in rural areas. Sustainable transportation in smart cities is a big challenge of our time, but before electric vehicles replace vehicles that burn fossil fuels we have to think about traffic optimization methods that reduce the amount of greenhouse gas emissions. Contents Comparison of Travel Time Measurements Using Floating Car Data and Intelligent Infrastructure Integration of Cellular Automata Traffic Simulator with CO2 Emission Model Impact of Dynamic Route Guidance System on CO2 Emission Naxos Vehicular Traffic Simulator Target Groups Lecturers and students of computer science, transportation and logistics Traffic engineers The Author Dr. Michal Markiewicz defended his PhD thesis in computer science at the University of Bremen,TZI Technologie-Zentrum Informatik und Informationstechnik, Germany. Currently, he is working on commercializat...

The Impact of a Potential Shale Gas Development in Germany and the United Kingdom on Pollutant and Greenhouse Gas Emissions

Science.gov (United States)

Weger, L.; Cremonese, L.; Bartels, M. P.; Butler, T. M.

2016-12-01

Several European countries with domestic shale gas reserves are considering extracting this natural gas resource to complement their energy transition agenda. Natural gas, which produces lower CO2 emissions upon combustion compared to coal or oil, has the potential to serve as a bridge in the transition from fossil fuels to renewables. However, the generation of shale gas leads to emissions of CH4 and pollutants such as PM, NOx and VOCs, which in turn impact climate as well as local and regional air quality. In this study, we explore the impact of a potential shale gas development in Europe, specifically in Germany and the United Kingdom, on emissions of greenhouse gases and pollutants. In order to investigate the effect on emissions, we first estimate a range of wells drilled per year and production volume for the two countries under examination based on available geological information and on regional infrastructural and economic limitations. Subsequently we assign activity data and emissions factors to the well development, gas production and processing stages of shale gas generation to enable emissions quantification. We then define emissions scenarios to explore different storylines of potential shale gas development, including low emissions (high level of regulation), high emissions (low level of regulation) and middle emissions scenarios, which influence fleet make-up, emission factor and activity data choices for emissions quantification. The aim of this work is to highlight important variables and their ranges, to promote discussion and communication of potential impacts, and to construct possible visions for a future shale gas development in the two study countries. In a follow-up study, the impact of pollutant emissions from these scenarios on air quality will be explored using the Weather Research and Forecasting model with chemistry (WRF-Chem) model.

Prevalence, correlates, and impact of coronary calcification on adverse events following PCI with newer-generation DES: Findings from a large multiethnic registry.

Science.gov (United States)

Copeland-Halperin, Robert S; Baber, Usman; Aquino, Melissa; Rajamanickam, Anitha; Roy, Swathi; Hasan, Choudhury; Barman, Nitin; Kovacic, Jason C; Moreno, Pedro; Krishnan, Prakash; Sweeny, Joseph M; Mehran, Roxana; Dangas, George; Kini, Annapoorna S; Sharma, Samin K

2018-04-01

We sought to determine the prevalence, predictors, and clinical impact of target lesion calcification in patients undergoing percutaneous coronary intervention (PCI) with newer generation drug-eluting stents (DES) and devices. Coronary calcification is independently associated with adverse outcomes following PCI. While newer DES and contemporary devices are considered safer and more efficacious, their influence on outcomes following PCI of heavily calcified lesions is unknown. We performed a retrospective analysis of a large, multiethnic cohort of patients undergoing PCI with new generation DES at an academic center between 2009 and 2013. Coronary calcification was qualitatively assessed as none/mild, moderate, or severe. Independent demographic, clinical, and anatomic predictors of moderate/severe calcification were identified using logistic regression. Associations between coronary calcification and 1-year MACE (death, myocardial infarction, or target vessel revascularization) were examined using Cox modeling. Compared to patients with none/mild (n = 10,180; 82.0%), those with moderate (n = 1,271; 10.0%) or severe (n = 994; 8.0%) calcification were older, more often Caucasian, had more complex target lesions, and worse renal function. The strongest demographic, clinical, and anatomic correlates of moderate/severe calcification were age, Caucasian race, renal dysfunction, lesion length, and left main location. Unadjusted MACE rates among those with none/mild, moderate, and severe calcification were 8.3, 14.6, and 17.8%, respectively (P < 0.001). After multivariable adjustment, the hazard ratio (95% CI) for MACE associated with moderate or severe coronary calcification was 1.63. Target lesion calcification remains independently associated with adverse outcomes in patients treated with newer generation DES and modern devices. © 2017 Wiley Periodicals, Inc.

Impact of Future Emissions and Climate Change on Surface Ozone over China

Science.gov (United States)

Ma, C. T.; Westervelt, D. M.; Fiore, A. M.; Rieder, H. E.; Kinney, P.; Wang, S.; Correa, G. J. P.

2017-12-01

China's immense ambient air pollution problem and world-leading greenhouse gas emissions place it at the forefront of global efforts to address these related environmental concerns. Here, we analyze the impact of ECLIPSE (Evaluating the Climate and Air Quality Impacts of Short-Lived Pollutants) future emissions scenarios representative of current legislation (CLE) and maximum technically feasible emissions reductions (MFR) on surface ozone (O3) concentrations over China in the 2030s and 2050s, in the context of a changing climate. We use a suite of simulations performed with the NOAA Geophysical Fluid Dynamics Laboratory's AM3 global chemistry-climate model. To estimate the impact of climate change in isolation on Chinese air quality, we hold emissions of air pollutants including O3 precursors fixed at 2015 levels but allow climate (global sea surface temperatures and sea ice cover) to change according to decadal averages for the years 2026-2035 and 2046-2055 from a three-member ensemble of GFDL-CM3 simulations under the RCP8.5 high warming scenario. Evaluation of the present-day simulation (2015 CLE) with observations from 1497 chiefly urban air quality monitoring stations shows that simulated surface O3 is positively biased by 26 ppb on average over the domain of China. Previous studies, however, have shown that the modeled ozone response to changes in NOx emissions over the Eastern United States mirrors the magnitude and structure of observed changes in maximum daily average 8-hour (MDA8) O3 distributions. Therefore, we use the model's simulated changes for the 2030s and 2050s to project changes in policy-relevant MDA8 O3 concentrations. We find an overall increase in MDA8 O3 for CLE scenarios in which emissions of NOx precursors are projected to increase, and under MFR scenarios, an overall decrease, with the highest changes occurring in summertime for both 2030 and 2050 MFR. Under climate change alone, the model simulates a mean summertime decrease of 1.3 ppb

Remind of the classification of some known isomeric transitions; Rappel de la classification des transitions isomeriques connues

Energy Technology Data Exchange (ETDEWEB)

Ballini, R; Levi, C; Papineau, L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1953-07-01

Relations of Berthelot (model of the liquid drop) and of Weisskopf (odd core to 'single' proton), between l'energie of a transition and her 'partial period' of emission of a {alpha} photon, are represented by easily usable diagrams. These relations are compared to the empiric relations for a certain number of groups of transitions. With regard to the M4 transitions, a rectification is given to the mode of treatment of the experimental results who had been proposed by Goldhaber and SUNYAR (1951). A test of systematic has been done, concerning the energy of isomeric transitions (grouping around some energies, variation of the nature, and of the energy of the transitions with Z, N and A). (author) [French] Les relations de Berthelot (modele de la goutte liquide) et de Weisskopf (noyau impair a proton ''celibataire''), entre l'energie d'une transition et la ''periode partielle'' d'emission d'un photon {alpha}, sont representees par des graphiques facilement utilisables. Ces relations sont comparees aux relations empiriques pour un certain nombre de groupes de transitions. En ce qui concerne les transitions M4, une rectification est donnee au mode de traitement des resultats experimentaux qui avait ete propose par GOLDHABER et SUNYAR (1951). Un essai de systematique a ete effectue, concernant l'energie des transitions isomeriques (groupement autour de certaines energies, variation de la nature et de l'energie des transitions avec Z, N et A). (auteur)

Life cycle air emissions impacts and ownership costs of light-duty vehicles using natural gas as a primary energy source.

Science.gov (United States)

Luk, Jason M; Saville, Bradley A; MacLean, Heather L

2015-04-21

This paper aims to comprehensively distinguish among the merits of different vehicles using a common primary energy source. In this study, we consider compressed natural gas (CNG) use directly in conventional vehicles (CV) and hybrid electric vehicles (HEV), and natural gas-derived electricity (NG-e) use in plug-in battery electric vehicles (BEV). This study evaluates the incremental life cycle air emissions (climate change and human health) impacts and life cycle ownership costs of non-plug-in (CV and HEV) and plug-in light-duty vehicles. Replacing a gasoline CV with a CNG CV, or a CNG CV with a CNG HEV, can provide life cycle air emissions impact benefits without increasing ownership costs; however, the NG-e BEV will likely increase costs (90% confidence interval: $1000 to $31 000 incremental cost per vehicle lifetime). Furthermore, eliminating HEV tailpipe emissions via plug-in vehicles has an insignificant incremental benefit, due to high uncertainties, with emissions cost benefits between -$1000 and $2000. Vehicle criteria air contaminants are a relatively minor contributor to life cycle air emissions impacts because of strict vehicle emissions standards. Therefore, policies should focus on adoption of plug-in vehicles in nonattainment regions, because CNG vehicles are likely more cost-effective at providing overall life cycle air emissions impact benefits.

Greenhouse impact of CH{sub 4}, N{sub 2}O and CFC emissions in Finland and its control potential

Energy Technology Data Exchange (ETDEWEB)

Pipatti, R.; Savolainen, I.; Sinisalo, J. [VTT Energy, Espoo (Finland)

1995-12-31

Methane (CH{sub 4}), nitrous oxide (N{sub 2}O) and chlorofluorocarbon (CFC) emissions contribute considerably to the anthropogenic enhancement of Earth`s greenhouse effect. The limitation of atmospheric concentrations of CH{sub 4} and N{sub 2}O is considered important also in the Climate Convention. Chlorine released from the CFCs in the stratosphere destroys ozone (O{sub 3}) and the emissions are therefore regulated with the Montreal Protocol. The greenhouse impact of CFCs might be, at least to some extent, compensated by the depletion of O{sub 3} which is also a greenhouse gas. The objective of the presentation is to assess the role of anthropogenic CH{sub 4}, N{sub 2}O, and CFC emissions in the total direct greenhouse impact due to human activities in Finland. The emission estimates for the gases are presented, as well as scenarios for emission history, future development and control potential. The greenhouse impact of the gases is compared with that of carbon dioxide (CO{sub 2}) emissions in Finland. (author)

Greenhouse impact of CH{sub 4}, N{sub 2}O and CFC emissions in Finland and its control potential

Energy Technology Data Exchange (ETDEWEB)

Pipatti, R; Savolainen, I; Sinisalo, J [VTT Energy, Espoo (Finland)

1996-12-31

Methane (CH{sub 4}), nitrous oxide (N{sub 2}O) and chlorofluorocarbon (CFC) emissions contribute considerably to the anthropogenic enhancement of Earth`s greenhouse effect. The limitation of atmospheric concentrations of CH{sub 4} and N{sub 2}O is considered important also in the Climate Convention. Chlorine released from the CFCs in the stratosphere destroys ozone (O{sub 3}) and the emissions are therefore regulated with the Montreal Protocol. The greenhouse impact of CFCs might be, at least to some extent, compensated by the depletion of O{sub 3} which is also a greenhouse gas. The objective of the presentation is to assess the role of anthropogenic CH{sub 4}, N{sub 2}O, and CFC emissions in the total direct greenhouse impact due to human activities in Finland. The emission estimates for the gases are presented, as well as scenarios for emission history, future development and control potential. The greenhouse impact of the gases is compared with that of carbon dioxide (CO{sub 2}) emissions in Finland. (author)

Les lexiques des jeunes dans les discours écrits des blogs : pour une approche descriptive

Directory of Open Access Journals (Sweden)

Lorenz Paulina

2014-07-01

Full Text Available S’il ne faut pas confondre ce qui est appelé communément « langage SMS » et « langage des jeunes », nous avancerons toutefois que les pratiques langagières écrites des jeunes sur les supports modernes de communication, et notamment dans les blogs, présentent des particularités encore peu étudiées. Les traits observables les plus saillants sont ceux de la morphologie graphique, mais il n’en reste pas moins que certains jeunes utilisent des lexiques particuliers dans les blogs qui méritent une attention particulière. Nous nous proposons donc d’étudier les différents lexiques utilisés par des jeunes de 12 à 22 ans dans les blogs de la plateforme skyrock.com aux niveaux de sa diversité, de ses usages sémantiques variable d’un scripteur à l’autre pour un même mot, et de ses particularités morphosyntaxiques. En effet, nous observerons des lexiques divers allant des lexiques perçus comme relevant des cités à des lexiques perçus comme étant « branchés-jeunes », ou encore à des lexiques propres aux supports modernes de communication. Ainsi, nous analyserons des lexiques variés dans leurs usages écrits tels que bolos, bédave, gérer, ouf, tigen, ou encore des lexiques empruntés tels que mouv, full, etc., ainsi que des emplois particuliers de séquences autonomes comme lol. Quelques questions périphériques complèteront notre analyse telle que celles qui concerne l’influence des usages lexicaux entre pairs et le savoir partagé, la distinction de différentes communautés en fonction des lexiques utilisés, ou encore la variabilité des représentations graphiques d’un même mot.

Impacts of decadal variations in natural emissions due to land-cover changes on ozone production in southern China

Directory of Open Access Journals (Sweden)

Mengmeng Li

2015-09-01

Full Text Available The decadal variations in emissions of high-reactivity biogenic volatile organics (BVOCs, as a result of land-cover changes, could significantly impact ozone (O3 production. In this study, the Weather Research and Forecasting/Chemistry (WRF/Chem modelling system, coupled with dynamic vegetation data sets derived from Moderate Resolution Imaging Spectroradiometer (MODIS, 2001–2012 and Advanced Very High Resolution Radiometer (AVHRR, early 1990s measurements, were used to investigate the impacts of land-cover changes on natural emissions, and consequently O3 production, in the Pearl River Delta (PRD region of southern China over the past two decades. Model results indicate that BVOC emissions were highly dependent on forest area. The total BVOC emissions in the modelling domain increased by a factor of two due to afforestation since the early 1990s, declined slowly (−5.8% yr−1 until 2006 and then increased continuously (+9.1% yr−1 to 2012. The decadal variations in BVOC emissions have complex implications for summer O3 production in PRD, depending on the chemical regimes and prevailing winds. The impacts on O3 production were most sensitive in downwind areas, and it was found that the large increase in BVOC emissions during 2006–2012 tended to reduce surface O3 concentrations by 1.6–2.5 ppb in rural regions, but caused an increment of O3 peaks by up to 2.0–6.0 ppb in VOC-limited urban areas (e.g., Guangzhou, Foshan and Zhongshan. The opposite was true in the period 2001–2006, when the reduced BVOC emissions resulted in 1.3–4.0 ppb increases in daytime O3 concentrations over northern rural regions. Impact of the two-fold increase in BVOC emissions since the early 1990s to 2006 was a 0.9–4.6 ppb increment in surface O3 concentrations over the downwind areas. This study suggests that the potential impacts on ozone chemistry should be considered in long-term land-use planning and air-quality management.

Evaluating the impacts of power plant emissions in Mexico

Energy Technology Data Exchange (ETDEWEB)

Lopez Villegas, M.T.; Tzintzun Cervantes, M.G.; Iniestra Gomez, R.; Garibay Bravo, V.; Zuk, M.; Rojas Bracho, L.; Fernandez Bremautz, A. [Direccion de Investigacion sobre Calidad del Aire, Inst. Nacional de Ecologia (Mexico)

2004-07-01

Mexican electricity generation has proven to be a large source of air pollution nationwide. According to the Energy Secretariat, electricity generation in Mexico accounts for 68% of SO{sub 2} emissions, 24% of PM{sub 10} emissions and 20% of NO{sub x} emissions nationwide. The country's total effective installed capacity is 42,067 MW, of which 67% corresponds to thermoelectric power plants. Heavy fuel oil, known as 'combustoleo', is used in many thermoelectric plants primarily for regular operation. The typical sulphur content of 'combustoleo' is approximately 2.5 to 4%. As a first step to determine the potential impacts of Mexican power plants on regional air pollution and health, we conducted a case study on the Adolfo Lopez Mateos power plant, located in the town of Tuxpan in the eastern state of Veracruz. The plant is located on the northern coast of the Gulf of Mexico; therefore greatly influenced by the weather of the region. We used the CALPUFF Lagrangian puff model (Earth Tech, Concord, MA) to simulate the dispersion of SO{sub 2}, NO{sub x} and primary PM{sub 10} emissions from the power plant stacks and the formation of secondary particulate matter. We considered a 120km x 120km grid, with a resolution of 2km x 2km and height of 2500 km. This area comprises approximately 791,000 inhabitants, including rural and urban populations. (orig.)

Evaluation de l'impact des activités anthropiques sur les organismes aquatiques dulçaquicoles. Méthodes et modèles pour la mesure de l'impact des rejets chimiques

OpenAIRE

Garric, J.

2008-01-01

/ Avant toute chose, je crois nécessaire de replacer le contexte de mes activités de chercheur à la fois au sein de l'organisme où j'ai réalisé ma carrière, mais également dans le cadre du domaine où j'ai travaillé, l'écotoxicologie. Après une formation en Sciences et Techniques de l'Eau à la faculté des Science de Montpellier (USTL) dans laquelle étaient étroitement associées des formations en chimie et en biologie, j'ai obtenu en 1980 un doctorat en Ecotoxicologie et Chimie de l'Environneme...

Cybergouvernement local en Égypte - intégration des ...

International Development Research Centre (IDRC) Digital Library (Canada)

Université du Caire d'examiner la maturité, l'efficacité et l'impact des services de cybergouvernement offerts par les gouvernorats sur Internet et par le truchement de bornes électroniques (dites " centres intelligents "). Le cadre d'évaluation ...

Including impacts of particulate emissions on marine ecosystems in life cycle assessment: the case of offshore oil and gas production.

Science.gov (United States)

Veltman, Karin; Huijbregts, Mark A J; Rye, Henrik; Hertwich, Edgar G

2011-10-01

Life cycle assessment is increasingly used to assess the environmental performance of fossil energy systems. Two of the dominant emissions of offshore oil and gas production to the marine environment are the discharge of produced water and drilling waste. Although environmental impacts of produced water are predominantly due to chemical stressors, a major concern regarding drilling waste discharge is the potential physical impact due to particles. At present, impact indicators for particulate emissions are not yet available in life cycle assessment. Here, we develop characterization factors for 2 distinct impacts of particulate emissions: an increased turbidity zone in the water column and physical burial of benthic communities. The characterization factor for turbidity is developed analogous to characterization factors for toxic impacts, and ranges from 1.4 PAF (potentially affected fraction) · m(3) /d/kg(p) (kilogram particulate) to 7.0 x 10³ [corrected] for drilling mud particles discharged from the rig. The characterization factor for burial describes the volume of sediment that is impacted by particle deposition on the seafloor and equals 2.0 × 10(-1) PAF · m(3) /d/kg(p) for cutting particles. This characterization factor is quantified on the basis of initial deposition layer characteristics, such as height and surface area, the initial benthic response, and the recovery rate. We assessed the relevance of including particulate emissions in an impact assessment of offshore oil and gas production. Accordingly, the total impact on the water column and on the sediment was quantified based on emission data of produced water and drilling waste for all oil and gas fields on the Norwegian continental shelf in 2008. Our results show that cutting particles contribute substantially to the total impact of offshore oil and gas production on marine sediments, with a relative contribution of 55% and 31% on the regional and global scale, respectively. In contrast, the

Contrôle des circuits auxiliaires des P.F.W. (arret machine 2004/2006)

CERN Document Server

Ottaviani, J

2005-01-01

Les PFW sont des nappes polaires installées sur les pôles des aimants du PS. Elles sont au nombre de 4 par unité d’aimant et constituées d’un circuit principal (dans lequel circule le courant désiré selon le cycle magnétique utilisé) et de circuits auxiliaires. Les circuits auxiliaires sont des enroulements de correction (boucles de tour et “pick-up” brasés sur les enroulements principaux). Pendant la variation du champ magnétique de l’aimant PS, on utilise des tensions induites dans ces circuits auxiliaires pour corriger les erreurs de champ dues aux pertes par courants de Foucault dans la chambre à vide. Chaque année, pendant l’arrêt machine, on vérifie si les caractéristiques des circuits auxiliaires correspondent aux normes (mesures des résistances des boucles de tours, résistances entre “pick-up” et isolation des circuits) afin de faire un suivi. Les 404 PFW sont ainsi vérifiées. Dans cette note, on ne relèvera que les PFW ayant des défauts (valeurs hors tolérances, ...

Impacts of energy crop cultivation on nature and landscape. Development and application of an evaluation method; Auswirkungen des Energiepflanzenanbaus auf Natur und Landschaft. Entwicklung und Anwendung einer Bewertungsmethode

Energy Technology Data Exchange (ETDEWEB)

Wiehe, Julia

2011-08-15

For long-term planning, knowledge about the interrelationship of effects of the cultivation method and the sensitivity of ecological balance is essential. Hence, the objective of this thesis is the development of a method for the evaluation of the impacts of bioenergy crop production for biogas use on the natural environment. The developed method is in alignment with existing methods. It is also in alignment with those methods used within the practice of landscape planning, so that the method as well as the derived conclusions can be implemented into landscape planning practice in the future. The evaluation method has been applied in the three model regions Hildesheim, Soltau-Fallingbostel and Emsland. These test areas represent different physical regions in Lower Saxony and typical agricultural production conditions. On the basis of these results, general statements on the impact of bioenergy crop production on the ecological balance of the area can be made. [German] Grundlage fuer eine vorausschauende Steuerung des Ausbaus erneuerbarer Energien ist die Kenntnis der Zusammenhaenge der Wirkung des Energiepflanzenanbaus und der Empfindlichkeit des Naturhaushaltes. Ziel der Arbeit ist daher die Erarbeitung einer Methode zur umfassenden Bewertung dieser Auswirkungen auf den Naturhaushalt. Die Methode orientiert sich an bereits bestehenden und in der Praxis der Landschaftsplanung angewendeten Bewertungsmethoden, so dass sie ebenso wie die daraus abgeleiteten Schlussfolgerungen zukuenftig Eingang in die Planungspraxis finden kann. Die Bewertungsmethode wird in den drei Modellregionen Hildesheim, Soltau-Fallingbostel und Emsland angewendet, mit denen die verschiedenen Naturraeume und fuer Niedersachsen typischen landwirtschaftlichen Produktionsbedingungen abgebildet werden. Auf Grundlage dieser Ergebnisse koennen dann allgemeine Aussagen zu den Auswirkungen des Energiepflanzenanbaus auf den Naturhaushalt gemacht werden.

Update on emissions and environmental impacts from the international fleet of ships: the contribution from major ship types and ports

Directory of Open Access Journals (Sweden)

S. B. Dalsøren

2009-03-01

Full Text Available A reliable and up-to-date ship emission inventory is essential for atmospheric scientists quantifying the impact of shipping and for policy makers implementing regulations and incentives for emission reduction. The emission modelling in this study takes into account ship type and size dependent input data for 15 ship types and 7 size categories. Global port arrival and departure data for more than 32 000 merchant ships are used to establish operational profiles for the ship segments. The modelled total fuel consumption amounts to 217 Mt in 2004 of which 11 Mt is consumed in in-port operations. This is in agreement with international sales statistics. The modelled fuel consumption is applied to develop global emission inventories for CO₂, NO₂, SO₂, CO, CH₄, VOC (Volatile Organic Compounds, N₂O, BC (Black Carbon and OC (Organic Carbon. The global emissions from ships at sea and in ports are distributed geographically, applying extended geographical data sets covering about 2 million global ship observations and global port data for 32 000 ships. In addition to inventories for the world fleet, inventories are produced separately for the three dominating ship types, using ship type specific emission modelling and traffic distributions.

A global Chemical Transport Model (CTM was used to calculate the environmental impacts of the emissions. We find that ship emissions is a dominant contributor over much of the world oceans to surface concentrations of NO₂ and SO₂. The contribution is also large over some coastal zones. For surface ozone the contribution is high over the oceans but clearly also of importance over Western North America (contribution 15–25% and Western Europe (5–15%. The contribution to tropospheric column ozone is up to 5–6%. The overall impact of ship emissions on global methane lifetime is large due to the high NO_x emissions. With

Etat des lieux des soins de premier recours des malades mentaux à Antananarivo : étude rétrospective

Science.gov (United States)

Bakohariliva, Hasina Andrianarivony; Rafehivola, Imisanavalona Hanitrinihaja; Raobelle, Evah Norotiana; Raharivelo, Adeline; Rajaonarison, Bertille Hortense

2018-01-01

Résumé Religion et guérisseurs traditionnels occupent encore une place prépondérante dans la prise en charge des maladies mentales à Madagascar. Ainsi, nous nous sommes fixés comme objectif d'établir un état des lieux sur les soins de premier recours des malades mentaux. Nous avons mené une étude rétrospective descriptive s'étalant sur une période de 16 mois allant de janvier 2014 en avril 2015 au sein du service de psychiatrie du CHU de Befelatanana à Antananarivo. La prévalence des psychoses était de 25%. Le genre féminin (53%), l'ethnie merina (77%), les étudiants (45%), le niveau d'étude secondaire (40%), les célibataires (72%), la religion protestante (45%), ainsi que le niveau socio-économique moyen (57,5%) étaient prédominants. Dans les paramètres cliniques, le mode de début brutal (52%), le premier recours à la religion (40%), la présence d'antécédents des cas similaire (90%), étaient majoritaires. La schizophrénie était la pathologie la plus rencontrée dans la moitié des cas. Le délai d'amélioration en cas de traitement religieux et traditionnels était dans la moitié des cas de plus de 10 jours d'hospitalisation. Les patients ayant reçu une prise en charge psychiatrique en premier recours, étaient améliorés dans 75 % cas en moins de 10jours. Le retard du recours aux soins psychiatriques est une réalité à Madagascar qui aggrave le pronostic des psychoses. PMID:29632623

Agriculture and greenhouse gases emissions reduction; Agriculture et reduction des emissions de gaz a effet de serre

Energy Technology Data Exchange (ETDEWEB)

Leguet, B.

2005-09-15

In France, the agriculture is the third sector of greenhouse gases emitter. Meanwhile since 1990 this sector poorly reduces its greenhouse gases. It is necessary to find mechanisms which allow the valorization of emissions reduction. In this framework the author presents the specificities of the greenhouse gases emissions of the agricultural sector, the possible incentives of emissions reduction, the reduction projects in France and abroad. (A.L.B.)

Reversible and irreversible impacts of greenhouse gas emissions in multi-century projections with the NCAR global coupled carbon cycle-climate model

Energy Technology Data Exchange (ETDEWEB)

Froelicher, Thomas L.; Joos, Fortunat [University of Bern, Climate and Environmental Physics, Physics Institute, Bern (Switzerland); University of Bern, Oeschger Centre for Climate Change Research, Bern (Switzerland)

2010-12-15

The legacy of historical and the long-term impacts of 21st century greenhouse gas emissions on climate, ocean acidification, and carbon-climate feedbacks are investigated with a coupled carbon cycle-climate model. Emission commitment scenarios with zero emissions after year 2100 and 21st century emissions of 1,800, 900, and 0 gigatons of carbon are run up to year 2500. The reversibility and irreversibility of impacts is quantified by comparing anthropogenically-forced regional changes with internal, unforced climate variability. We show that the influence of historical emissions and of non-CO{sub 2} agents is largely reversible on the regional scale. Forced changes in surface temperature and precipitation become smaller than internal variability for most land and ocean grid cells in the absence of future carbon emissions. In contrast, continued carbon emissions over the 21st century cause irreversible climate change on centennial to millennial timescales in most regions and impacts related to ocean acidification and sea level rise continue to aggravate for centuries even if emissions are stopped in year 2100. Undersaturation of the Arctic surface ocean with respect to aragonite, a mineral form of calcium carbonate secreted by marine organisms, is imminent and remains widespread. The volume of supersaturated water providing habitat to calcifying organisms is reduced from preindustrial 40 to 25% in 2100 and to 10% in 2300 for the high emission case. We conclude that emission trading schemes, related to the Kyoto Process, should not permit trading between emissions of relatively short-lived agents and CO{sub 2} given the irreversible impacts of anthropogenic carbon emissions. (orig.)

Climate and competitiveness: An economic impact assessment of EU leadership in emission control policies

Energy Technology Data Exchange (ETDEWEB)

Alexeeva-Talebi, V.; Boehringer, C.; Moslener, U. [Centre for European Economic Research, Mannheim (Germany)

2007-07-01

The European Council has recently claimed to consider ambitious emission reduction targets (15 to 30 percent by 2020 as compared to 1990 levels) to limit global climate change. In light of the coexistent EU priorities under the Lisbon process, the authors analyze alternative unilateral EU emission control policies against their effects on EU (sectoral and economy-wide) competitiveness using a multi-sector, multi-region computable general equilibrium (CGE) model framework. For a given emission reduction target, the simulations show that alternative implementation rules (uniform versus sectorally differentiated carbon taxes) induce ambiguous impacts on sectoral competitiveness: For a uniform tax, relatively carbon-intensive EU industries face competitiveness losses, while carbon-extensive sectors improve their ability to compete internationally. Losses and gains are reinforced by the stringency of unilateral emission reduction targets. Thus, the implementation of an (economically efficient) uniform carbon tax induces structural change which inevitably goes at the expense of carbon-intensive industries. Vice versa, the authors find that more pronounced tax differentiation in favor of carbon-intensive industries can largely neutralize the negative impacts of emission constraints on their competitiveness, but goes at the expense of overall efficiency. In this case, adjustment costs of emission abatement will to a large extent be born by energy-extensive sectors in terms of a deteriorated ability to compete. As a middle course, moderate tax differentiation allows to sectorally balance competitiveness effects of emission control policies and at the same time limit overall efficiency losses. The authors find also that the level of tax differentiation to balance sectoral competitiveness effects and to limit overall efficiency losses is independent of the emission reduction target. Furthermore, the results indicate that the magnitude of sectoral competitiveness effects is

Profil bactériologique du pied diabétique et son impact sur le choix des antibiotiques

Science.gov (United States)

Zemmouri, Adil; Tarchouli, Mohamed; Benbouha, Abdellatif; Lamkinsi, Tarik; Bensghir, Mustapha; Elouennass, Mostafa; Haimeur, Cherqui

2015-01-01

Introduction Analyse du profil bactériologique des pieds diabétiques pris en charge à l'hôpital militaire de Rabat et son influence sur l'antibiothérapie de première intention. Méthodes Etude prospective non randomisée étalée sur 18 mois, ayant concerné 105 patients. Après recueil des données et en attente des résultats bactériologiques nos patients ont été divisés en deux groupes: un groupe a été mis sous Amoxicilline + Acide clavulanique + Gentamycine (59 patients) et un groupe sous Ertapénème±Gentamycine (46 patients). Résultats L’étude a regroupé 85 hommes et 20 femmes (sexe ratio = 4.26). L’âge moyen est de 64.4 ans. La gangrène a été observée chez 79% des malades; elle était humide-donc surinfectée en principe- dans 43% des cas. Par ailleurs, 67% des malades ont un chiffre de globules blancs 12000 définissant une infection sévère. L'ostéolyse a été mise en évidence chez 27% de nos patients. Parmi les différentes techniques de prélèvements: 81% ont été profonds dont 21% de biopsie osseuse per opératoire et 14% de prélèvements combinés. 42% de ces prélèvements sont poly microbiens et 21% sont stériles. Les résultats bactériologiques viennent confirmer la prédominance des bactéries aérobies à Gram positif. Le taux de remplacement de l'Ertapénème est de 22% contre un taux de 50% pour l'Amoxiclav. Conclusion L'antibiothérapie ne doit être instaurée qu'en cas d'infection du pied diabétique diagnostiquée sur les critères cliniques établis par les consensus internationaux récents. Le respect des mesures de lutte contre la diffusion de la résistance bactérienne s'avère primordiale. PMID:27386024

Kinetic electron emission from metal surfaces induced by impact of slow ions

Czech Academy of Sciences Publication Activity Database

Šroubek, Zdeněk; Lorinčík, Jan

-, č. 625 (2014), s. 7-9 ISSN 0039-6028 R&D Projects: GA MŠk(CZ) ME10086 Institutional support: RVO:67985882 Keywords : Ion induced kinetic electron emission * Electronic excitation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.925, year: 2014

Accès à l'eau : des solutions techniques et sociales aident des ...

International Development Research Centre (IDRC) Digital Library (Canada)

Grâce à la modélisation par ordinateur faisant appel à des techniques de pointe et à la consultation des collectivités, l'organisme bolivien Agua Sustentable a trouvé des solutions politiques à des conflits qui auraient pu s'avérer désastreux au sujet de l'accès à l'eau. Cet organisme de recherche subventionné par le CRDI a ...

Le Débat des semences

International Development Research Centre (IDRC) Digital Library (Canada)

Solutions pour les lois nationales régissant le contrôle des ressources génétiques et des ...... des pouvoirs) qui reconnaissent, dans une certaine mesure, les droits de gestion collectifs des ...... documentés, les performances physiques, etc.

Impact de la qualité de l'audit externe sur la liquidité des titres des entreprises tunisiennes cotées : Investigation théorique et évidence empirique

OpenAIRE

Hakim Ghorbel , Faten

2008-01-01

International audience; Cette recherche a pour objectif d'étudier l'impact de la qualité d'audit externe sur la liquidité. Nous appréhendons la qualité d'audit dans le cadre de notre étude par "la qualité de l'auditeur", et notamment de son indépendance et de ses compétences. Après avoir contrôlé l'effet d'autres variables censées, d'après la théorie, influencer la liquidité, les tests effectués ont permis de dégager une relation positive entre l'appartenance des auditeurs à un réseau interna...

Assessment of chemical emissions in life cycle impact assessment - focus on low substance data availability and

DEFF Research Database (Denmark)

Larsen, Henrik Fred

2004-01-01

impact approaches, i.e. the assessment factor-based PNEC approach and the PAF-based approach, shows pros and cons for both. However, taking the comparative nature of LCA and its aim for best estimate into account, and combining this with the possibilities for reducing the data demand of an EC50-based PAF......Life cycle assessment (LCA) studies on products or services seem generally to be carried out without a proper inclusion of potential toxic impacts from emissions of chemicals. The first goal of the thesis is to investigate this statement and to clarify whether or not the outcome of an LCA can...... of substance data on known emissions. To be able to characterize the potential toxic impacts on humans and the environment of chemical emissions, substance data on fate and effect are needed. The second goal of this thesis is to investigate how to deal with low substance data availability on especially effect...

Fuel choices for fuel-cell vehicles : well-to-wheel energy and emission impacts

International Nuclear Information System (INIS)

Wang, M.

2002-01-01

Because of their high energy efficiencies and low emissions, fuel-cell vehicles (FCVs) are undergoing extensive research and development. While hydrogen will likely be the ultimate fuel to power fuel-cell vehicles, because of current infrastructure constraints, hydrogen-carrying fuels are being investigated as transitional fuel-cell fuels. A complete well-to-wheels (WTW) evaluation of fuel-cell vehicle energy and emission effects that examines (1) energy feedstock recovery and transportation; (2) fuel production, transportation, and distribution; and (3) vehicle operation must be conducted to assist decision makers in selecting the fuel-cell fuels that achieve the greatest energy and emission benefits. A fuel-cycle model developed at Argonne National Laboratory--called the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model--was used to evaluate well-to-wheels energy and emission impacts of various fuel-cell fuels. The results show that different fuel-cell fuels can have significantly different energy and greenhouse gas emission effects. Therefore, if fuel-cell vehicles are to achieve the envisioned energy and emission reduction benefits, pathways for producing the fuels that power them must be carefully examined.

Effet de la mise en culture des forêts secondaires sur les ...

African Journals Online (AJOL)

L'impact de la mise en culture des forêts sur les peuplements de macroinvertébrés du sol a été étudié en moyenne Côte d'Ivoire avec pour objectif d'identifier les plus sensibles à la perturbation des forêts. Les macroinvertébrés du sol de parcelles de forêt secondaire et de cultures vivrières ont été échantillonnés en utilisant ...

Performances de ponte et qualité des oeufs des poules pondeuses ...

African Journals Online (AJOL)

Les performances de ponte et la qualité des oeufs de 216 poules pondeuses ISA Brown âgées de 21 semaines ont été déterminées en les alimentant avec des rations contenant des feuilles séchées de manioc (Manihot esculenta, Crantz). Pendant douze semaines, trois groupes de 72 poules chacun (réparties en trois ...

Freins et leviers à la diversification des cultures : étude au niveau des exploitations agricoles et des filières

Directory of Open Access Journals (Sweden)

Meynard Jean-Marc

2013-07-01

Full Text Available La diversification des cultures est souvent présentée comme un levier d’action pour accroître la durabilité des systèmes de production agricoles. Bien raisonnée, elle favorise en effet une réduction de l’usage d’intrants extérieurs à l’exploitation – pesticides, engrais, eau – et des nuisances environnementales associées à leur utilisation excessive. À l’inverse, la simplification des systèmes de culture engagée depuis plus de 40 ans s’est accompagnée d’un recours croissant aux intrants. Cependant, malgré son intérêt pour les systèmes de production en termes de durabilité écologique mais aussi économique (répartition des risques, et son inscription dans divers plans et dispositifs incitatifs, la diversification des cultures progresse peu. Les ministères en charge de l’agriculture et de l’environnement ont donc commandé à l’INRA une étude visant à identifier les freins à la diversification des cultures en France et les leviers mobilisables, par les pouvoirs publics notamment, pour la favoriser. L’hypothèse de travail est que ces freins relèvent du fonctionnement global du système agro-industriel, et de la capacité de développement de filières valorisant les cultures de diversification. L’étude a examiné un certain nombre de cas représentatifs de la diversité des filières et notamment de leurs modes d’organisation, qui déterminent la coordination et l’engagement des acteurs économiques impliqués dans le développement d’une culture de diversification.

Effets des pesticides seuls et en mixtures sur les biofilms périphytiques

OpenAIRE