WorldWideScience

Sample records for gaz periode 2009-2020

  1. Natural gas news; Gaz actualites

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1998-12-01

    This brochure is a compilation of practical information concerning the Gaz de France group: organization chart, daughter companies, services, economical activity, natural gas market, trade, regulations etc. A list of partners, directions, centres, groups, associations and other various organisms in relation with Gaz de France company is given. (J.S.)

  2. Pluri annual indicative plan of the investments in the gas sector; Plan indicatif pluriannuel des investissements dans le secteur du gaz Periode 2006-2015

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-03-15

    This indicative plan constitutes the first report to the Parliament. It is a prospective document for the period 2006-2015 containing: a forecast of the gas demand increase, a description of main investments decided in matter of gas infrastructures, a diagnostic concerning the adequation between the supplying capacities in natural gas and the national needs, a series of recommendations on the State tools to guarantee the national supplying security and on the investment. The four parts deal with the stakes and perspectives of the national natural gas supplying, the demand evolution, the offer evolution and the equilibrium offer. (A.L.B.)

  3. Gaz de France. Operation note; Gaz de France. Note d'operation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This note was published for the public at the occasion of the admission to Euronext's Eurolist of the existing shares that make the capital of Gaz de France company, the French gas utility. The note gives some informations about Gaz de France activity, and about its strategy of development in the European gas market. Then it describes the offer relative to the opening of Gaz de France capital. Some selected financial data and some precision about the risk factors and the management of the company complete the document. (J.S.)

  4. Gaz de France. Source document; Gaz de France. Document de base

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This document was issued by Gaz de France, the French gas utility, at the occasion of the opening of the capital of the company. It is intended to shareholders and presents some informations relative to the stocks admitted to Euronext's Eurolist, some general informations about the company and its capital, some informations about the activities of Gaz de France group, about its financial situation and results, about its management, and about its recent evolution and future perspectives. (J.S.)

  5. Gaz de France annual report 2003; Gaz de France rapport annuel 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    Today, Gaz de France Group ranks as one of the largest gas utilities in Europe. This success is the fruit of a growth strategy that fuses economic, social and environmental imperatives. To respond more efficiently to fluctuations in the natural gas market and continue to expand its range of competitive products and services, Gaz de France has committed to integrated development across the full spectrum of natural gas activities, from exploration and production to the sale of energy and related services. As the leading supplier of natural gas in France, Gaz de France has honed a targeted policy to acquire equity interests and assets, mainly in Europe, assuring the Group of a privileged place at the heart of the European gas grid. As European energy markets continue to open more widely to competition, the Group intends to benefit from its presence in all the sectors of the natural gas industry and in the European market to confirm its position as an integrated energy operator, focused on gas, among Europe's leaders. To achieve this goal, Gaz de France will concentrate in a balanced fashion on activities linked to infrastructures and activities related to energy supply and services. While assuming its public service responsibilities, the Group will expand the range of products and services to customers. This activity report presents: consolidated financial highlights, profile, corporate governance, Gaz de France's ambition, panorama of activities: energy supply and services (exploration - production, purchase and sale of energy, services), infrastructures (transmission and storage - France, distribution - France, transmission and distribution - international), Commitments of Gaz de France (human resources, research and development, sustainable development, map of main subsidiaries and affiliates)

  6. Gaz de France annual report 2001; Gaz de France rapport annuel 2001

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    One of Europe's leading gas utilities, the Gaz de France Group operates in all sectors of the natural gas industry, from exploration and production to energy distribution and services, to respond to customer demand efficiently and achieve sustained and profitable growth. To this end, the Group is organized in five lines of business: exploration and production, supply and trading, transmission, distribution and services. Active in 33 countries, the Gaz de France Group first targets growth in Europe, its natural environment. The opening of energy markets and its position at the center of Europe's gas grids offers the Group many opportunities in trading, transmission for third parties, distribution and services. Since August 10, 2000, Gaz de France has made it possible for other gas operators to access its transmission system. The Group capitalizes on its expertise at the global level as well, in emerging markets like Mexico and in fields in which it has recognized know-how, such as liquefied natural gas (LNG). To ensure this growth and pursue its penetration of European and world markets, the Gaz de France Group implements a policy of cooperation and partnership with other energy sector operators, demonstrates its well-developed ability to innovate and practices a customer-focused organization that offers competitive, tailored services to residential users, companies and local governments. The Group has chosen to pursue this growth through a strategy of sustainable development. By making natural gas more accessible and promoting its uses, Gaz de France integrates demand-side management of energy, fosters human development and ensures environmental protection in France, Europe and the world. This activity report presents: the corporate profile of the group, the international natural gas businesses, the financial highlights, the growth objectives of the group in all its businesses (exploration and production, supply and trading, transmission, distribution

  7. The public safety and Gaz de France; La securite du public et Gaz de France

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    In the framework of its utilities missions, Gaz de France has to assure the public safety and the continuity of the gas supply chain. To avoid accidents and help victims of accidents, Gas de France implemented a system of financial assistance but also a preventive action to verify the installations. The first part of the document presents the liabilities of Gas de France, the second part deals with the voluntarist approach of Gas de france towards the public safety. (A.L.B.)

  8. Gaz de France annual report 2000; Gaz de France rapport annuel 2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    A leader in the natural gas market in Europe, Gaz de France is an integrated group active in all sectors of the natural gas industry. In exploration and production, trading of natural gas, transmission, storage, distribution, energy management, air conditioning and heating, the Group has developed recognized skills and know-how both upstream and down to assure its customers of diversified, efficient and competitive services. A leader in liquefied natural gas, storage and distribution technologies, the Gaz de France Group has strong positions in Europe and operates throughout the world by promoting a strategy of alliances and partnerships at all levels of the gas industry. The goal of the Gaz de France Group is to continue to expand and develop its activities from the wellhead to the burner tip, and to seize, in France and throughout the world, the best opportunities offered to capitalize on its strengths. This activity report presents: the corporate profile, the financial highlights, the principal subsidiaries and affiliates, the major European trunk lines the responsive, customer-focused services (exploration-production, trading, transmission, distribution, services), the actions to ensure performance (productive research, comprehensive quality assurance, mobilized workforce ready for the opening of the markets)

  9. Gaz de France 2006 sustainable development report; Gaz de France 2006 rapport developpement durable

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    A major European energy utility, the Gaz de France Group produces, purchases, transports, distributes and sells natural gas, electricity and related services for its residential, corporate and local government customers. this report presents the actions implemented by the group to incorporate sustainable development into its strategy. From the point of view of risks and opportunities, the group analyzes what it takes to ensure development that respects people and the environment, and it implements them in all its business lines and management systems. Content: Gaz de France, portrait of a major energy utility, highlights of 2006, challenges and strategy (defining strategy and sustainable development policy, specific risks and opportunities, activities of the Gaz de France group: challenges, impact for stakeholders, transparency and independence in governing), ranking and implementing (defining sustainable development policy: reviewing priorities, meeting all the challenges, publicizing and defending positions, increasing awareness, overseeing and monitoring results), results of the 2004-2006 sustainable development action plan, dialogue and action with stakeholders, performance assessment, performance in response to challenges: energy challenges (guaranteeing regular supplies, controlling atmospheric emissions, promoting energy conservation, developing renewable energy), industrial challenges (ensuring health and safety, limiting the overall environmental impact of group activities), social responsibility challenges (advocating corporate social responsibility, promoting human rights and fighting corruption, encouraging commitment to solidarity, promoting regional development through local initiatives, reconciling acquisitions, procurement and sustainable development, ensuring transparency in natural gas rates, providing shareholders with quality information, promoting diversity, a source of enrichment, making working conditions a performance factor), indicators and

  10. Gaz de France and the sustainable development in 2005; Gaz de France et le developpement durable en 2005

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This booklet provides information on the Gaz de France group involvement in the sustainable development: the stakes, the approach, the energy challenge answers, the security and the solidarity and the active part in the territories development. (A.L.B.)

  11. Gaz de France. 2006 reference document; Gaz de France. Document de reference 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This document was issued by Gaz de France, the French gas utility, at the occasion of the opening of the capital of the company. It is intended to shareholders and presents the relevant informations relative to the annual consolidated financial statements of the group according to IFRS and French standards for the year 2005 (selected financial information, business overview, liquidity and capital resources, profit forecasts or estimates, compensation and benefits, issuer assets etc..). It includes also some complementary information about the activities of the group, its estate property, plants and equipments, its R and D and patenting activities, its management and administration, its 2005 and 2006 contracts etc.. (J.S.)

  12. Greenhouse effect gases inventory in France during the years 1990-1999; Inventaire des emissions de gaz a effet de serre en France au cours de la periode 1990-1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    The present report supplies emission data, for France and for the period 1990-1999, concerning all the substances involved in the increase in the greenhouse effect and covered under the United Nations' Framework Convention on Climate Change (UNFCCC). The substances are the six direct greenhouse gases covered by the Kyoto protocol: carbon dioxide (CO{sub 2}), methane (CH{sub 4}), nitrous oxide (N{sub 2}O), the two species of halogenous substances - hydro-fluorocarbons (HFCs) and per-fluorocarbons (PFCs), and sulphur hexafluoride (SF{sub 6}). Emissions of sulphur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), non methane volatile organic compounds (NMVOCs), and carbon monoxide (CO), gases which indirectly make a significant contribution to the greenhouse effect, are reported under the Convention. The emissions of the six gases that directly contribute to the greenhouse effect are expressed in terms of Global Warming Potential (GWP) which decreased by 2.1 % in 1999 compared to 1990. The emissions of the four gases that indirectly contribute to the greenhouse effect are moving towards decrease: this is by 17% for NO{sub x}, 23% as regards NMVOCs, 33% for CO and by 44% regarding SO{sub 2}. Out of the six greenhouse gases covered by the Kyoto Protocol, CO{sub 2} accounts for the largest share in total GWP emissions (70 %), followed by N{sub 2}O (16 %), CH{sub 4} (12 %), HFCs (0.99 %), SF{sub 6} (0.5 %), and PFCs (0.39 %). (author)

  13. Natural Gas Storage Seismic Monitoring Suivi sismique des stockages de gaz naturel

    Directory of Open Access Journals (Sweden)

    Mari J.L.

    2011-02-01

    Full Text Available IFP Energies nouvelles, CGGVeritas and GDF Suez have conducted together, since 1980, a series of seismic monitoring experiments in order to detect and follow the movements of the gas plume in natural gas geologic storages. Surface and well seismic surveys were carried out at different stages of the storage life. Permanent receiver arrays have been set down in wells. Permanent sources have been designed. Sources and receivers have been used to follow continuously the storage cycle during several years, providing time measurement accuracy within a tenth of a millisecond. Gas intrusion into an aquifer leads to an increase in the arrival times of reflections beneath the storage reservoir and to a variation of the reflection amplitudes at top and bottom of the reservoirs. Progressive variations of the seismic parameters may be followed during the initial infill period. Further movements of the gas plume with the annual in/out cycles are more difficult to follow, because of the simultaneous presence of gas and water in the pores. Arrival time variations of some tenths of a millisecond may be detected and measured. Saturations, using accurate picking of the arrival times, can be estimated in favourable cases. Because of the higher density of carbon dioxide, when stored in a supercritical phase, sensitivity of the seismic parameters, velocity, density and acoustic impedance to saturation variations will be about twice smaller for CO2 storages than it is for methane. IFP Energies nouvelles, la CGGVeritas et GDF Suez ont mené ensemble, depuis 1980, de nombreuses expériences de monitoring sismique afin de détecter et de suivre les mouvements du gaz dans des stockages géologiques de gaz naturel. Des acquisitions ont été réalisées à différents stades de la vie du stockage tant en sismique de surface qu’en sismique de puits. Des antennes de récepteurs permanentes ont été construites et implantées dans des puits. Des sources permanentes ont

  14. Gaz de France 2006 annual report; Gaz de France 2006 rapport d'activite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Gaz de France is major European energy utility, which produces, purchases, transports, distributes and sells natural gas, electricity and related services for its residential, corporate and local government customers. Its strategic focuses are to develop an ambitious marketing strategy, pursue a supply and procurement policy that guarantees the Group's competitiveness, confirm its position as a benchmark infrastructure manager, and speed up its profitable growth in Europe. Gaz de France aligns its strategy with a concrete and ambitious sustainable development policy. Its growth model is based on responsiveness to customers and constructive dialogue with its employees and partners. This document is the activity report of the group for the year 2006. It presents: 1 - the corporate profile of the group; 2 - its strategies (energy, energy supply, infrastructures); 3 - its financial highlights; 4 - its governance, shareholders and human resources; 5 - the activities of the group (exploration and production, energy procurement, energy sales, services, transmission France, storage France, LNG terminals, distribution France, transmission and distribution international, research and development); 6 - its 2006 financial data and financial summary.

  15. Gaz de France: first half 2007 results

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Paris, 29 August 2007, Gaz de France Group presents its first half 2007 results (billion euros): Sales revenue 13.78 (-11% with respect to 2006), EBITDA 3.11 (-4.9%), Operating income 2.33 ( -8.7%), Net income Group share 1.51 (-11%), Net income Group share per share 1.53 euro (-11%). The half-year results are attributable primarily to three factors: - A very difficult environment with exceptionally mild climate conditions in the first half, impacting nearly all of the businesses, and unfavourable market conditions, reflected in particular in the low gas prices on the markets; - A tariff context which did not negatively impact the sales margins following a very difficult year 2006; - Good performance in international activities. Despite the environment, the Group is maintaining its financial target for 2007, as announced in March this year: 2007 will be a year of consolidation. EBITDA is expected to be in line with that of 2006. This target assumes average climate conditions during the second half 2007.

  16. Gaz de France: first half 2007 results

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Paris, 29 August 2007, Gaz de France Group presents its first half 2007 results (billion euros): Sales revenue 13.78 (-11% with respect to 2006), EBITDA 3.11 (-4.9%), Operating income 2.33 ( -8.7%), Net income Group share 1.51 (-11%), Net income Group share per share 1.53 euro (-11%). The half-year results are attributable primarily to three factors: - A very difficult environment with exceptionally mild climate conditions in the first half, impacting nearly all of the businesses, and unfavourable market conditions, reflected in particular in the low gas prices on the markets; - A tariff context which did not negatively impact the sales margins following a very difficult year 2006; - Good performance in international activities. Despite the environment, the Group is maintaining its financial target for 2007, as announced in March this year: 2007 will be a year of consolidation. EBITDA is expected to be in line with that of 2006. This target assumes average climate conditions during the second half 2007.

  17. Gaz de France and market regulation; Gaz de France et la regulation

    Energy Technology Data Exchange (ETDEWEB)

    Carriere, J.F.; Balard, Th. [Gaz de France (GDF), 75 - Paris (France)

    2004-10-01

    Following an overview of the specific features of the European gas sector (characterised by highly concentrated production and increasing levels of production outside Europe and over long distances), the article describes the lead up to the opening of the market place in France. Following the application of the first directive in 2000, Gaz de France has carried out various measures, the aim of which was to achieve immediate efficiency (with the organizational separation of the transport and trading divisions, the separation of activities from an accounting viewpoint and the publication of a transparent TPA tariff as opposed to a discriminatory one). This opening of the gas sector has seen the start of a gradual process based on this experience. In addition to these initial measures, the opening of the gas markets has been subject to a regulatory framework as from January 2003, and the task of regulating the French gas sector has been given to the CRE (Commission de regulation de l'electricite). Thanks to the ongoing dialogue initiated by the latter with all key players in the market, progress has been achieved in various fields related to regulation. Even if this process is not complete, the French example demonstrates that the combined actions of the regulator and the market operators working together in a constructive manner and in stages, makes it possible to successfully introduce a genuinely open market. (authors)

  18. A contribution from Gaz de France to the economic performance of industries; Contribution de Gaz de France a la perfomance economique des industriels

    Energy Technology Data Exchange (ETDEWEB)

    Depail, J.C. [Gaz de France (GDF), 75 - Paris (France)

    1996-12-31

    The aim of the policy of the French national gas utility, Gaz de France, towards industries, is to promote natural gas as a competitive fuel compared to fuels and electric power, with energy efficient solutions that are easy to implement and maintain: space heating, paint curing, surface cleaning, bath heating, vapour generation, waste treatment (especially for molding sand and volatile organic compounds, sludge drying). Gaz de France proposes also expertise schemes and audits

  19. Application de la combustion catalytique aux turbines à gaz

    Science.gov (United States)

    Lebas, E.; Martin, G. H.

    2002-04-01

    La réduction des émissions d'oxydes d'azote sur turbines à gaz est obtenue par diminution de la température au sein de la chambre de combustion. Les techniques possibles comprennent l'injection d'eau ou de vapeur, la combustion pauvre et l'oxydation catalytique. Parmi celles-ci, la dernière est la plus prometteuse en terme de coûts et de performances, avec des émissions de NOx ramenées à un seul chiffre (typiquement inférieures à 3 ppm). L'IFP travaille depuis maintenant 10 ans sur l'adaptation de la combustion catalytique aux turbines à gaz. Les études ont été conduites au travers de projets européen tels que AGATA (Advance Gas Turbine for Automotive Application) et ULECAT (Ultra Low CATalytic combustor for dual fuel gas turbine). Le premier projet était destiné au développement de véhicules hybrides et le second à la combustion stationnaire de biogaz et de combustible Diesel. Les études en cours dans ce domaine portent sur le développement d'une unité de cogénération intégrant une microturbine à combustion catalytique. Les travaux menés à l'IFP concernent la mise au point de catalyseurs répondant aux exigences de la combustion catalytique en turbine à gaz et le développement de chambres de combustion permettant la mise en oeuvre de ces catalyseurs.

  20. Géochimie des gaz naturels et origine des gisements de gaz en Europe occidentale Geochemistry of Natural Gas and Origins of Gas Fields in Western Europe

    Directory of Open Access Journals (Sweden)

    Tissot B.

    2006-11-01

    Full Text Available De nombreux gisements de gaz sont connus en Europe, dans des conditions géologiques très diverses et dans des terrains d'âge Paléozoïque à Pleistocène. Le problème de leur origine peut être élucidé par l'étude de la composition chimique et isotopique des gaz associée à la connaissance de l'histoire géologique. On rappellera d'abord le schéma général de formation de l'huile et du gaz dans les bassins sédimentaires, puis on discutera les conditions particulières de formation des divers types de gaz. Enfin, on passera en revue, à titre d'exemple, un certain nombre de gisements de gaz d'Europe occidentale. A great many gas fields are known in Europe, having a wide variety of geological conditions and in formations ranging in age from the Paleozoic to the Pleistocene. The problem of their origin can be explained by analyzing the chemical and isotopic composition of the gases combined with knowing the geological history. This article first reviews the general pattern of oil and gas formation in sedimentary basins and then goes on to discuss the specific conditions for the formation of different types of gas. It concludes with a review of various gas fields in Western Europe.

  1. Le Gaz Naturel Véhicule Natural Gas for Vehicles

    Directory of Open Access Journals (Sweden)

    De Chauveron S.

    2006-11-01

    Full Text Available Cet article présente le GNV (Gaz Naturel Véhicule. Le GNV a en effet de sérieux atouts, à la fois comme carburant de substitution et comme carburant propre. Ces atouts sont aussi bien économiques que techniques. La première partie est consacrée aux enjeux du développement du GNV. Les premiers pays utilisateurs ont été ceux qui disposent sur leur sol de ressources de gaz naturel. Aujourd'hui, alors que de nombreux pays doivent faire face à l'inquiétude croissante relative à l'augmentation de la pollution urbaine, le gaz naturel apparaît également comme un carburant propre, permettant de réduire rapidement les émissions de polluants des véhicules. Dans une deuxième partie, nous donnons une description technique sommaire des stations GNV et des véhicules GNV. Il s'agit de familiariser le lecteur avec les quelques spécificités techniques du GNV, par rapport à l'essence et au gazole. On constatera d'ailleurs que les technologies GNV sont très proches des technologies classiques. Enfin, la dernière partie est consacrée aux actions en cours, qui permettront le développement du GNV en France et en Europe : programmes de recherche, réduction des coûts de la filière, actions réglementaires, communication, etc. This article presents compressed natural gas for vehicles (CNG, which can provide considerable advantages both as an alternative fuel and as a clean fuel. These assets are not only economic but also technical. The first part deals with what is at stake in developing natural gas as a motor fuel. The first countries to use CNG were those with natural gas resources in their subsoil. Today, with a large number of countries having to cope with growing concern about increasing urban pollution, natural gas is also seen as a clean fuel that can help cut vehicle pollutant emissions dramatically. In the second part a brief technical description is given of CNG stations and vehicles, with the aim of acquainting the reader with

  2. Gaz de France adopts low hydrogen, downhill welding

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-01

    Gaz de France has become the first gas transmission pipeline operator to adopt the low-hydrogen, downhill welding technique made possible by the introduction of the Phillips 27PM electrodes. The use of these electrodes permits tie-in joints at road, railway, and river crossings, where optimum security demands a low-hydrogen-content weld metal. Welding of the 90-mile section from the Nozay compressor station to Le Mans involved some 1100 tie-in weld joints. Spie-Capag, contractor for the section, confirmed the 27PM electrode's success: The downhill welding method resulted in faster filling and capping passes than for cellulosic or uphill low-hydrogen electrodes, while the repair rate compared favorably with that for regular line joints.

  3. Conversion chimique du gaz naturel Chemical Conversion of Natural Gas

    Directory of Open Access Journals (Sweden)

    Chaumette P.

    2006-11-01

    Full Text Available Dans cet article sont passés en revue les travaux de recherche et développement et les procédés existants dans le domaine de la conversion chimique du gaz naturel. Les deux voies possibles, conversion directe du méthane et conversion indirecte, via le gaz de synthèse, sont présentées. Tant la préparation d'hydrocarbures utilisables comme carburants, que celle des composés de bases pour la pétrochimie ou la chimie sont évoquées. L'accent est mis sur l'étape clé du développement de chaque procédé qui, selon le produit visé, consiste en la mise au point d'un nouveau système catalytique, en un changement de la technologie du réacteur, ou en la mise au point d'une section fractionnement moins complexe. This article reviews the research and development work and the existing processes in the area of chemical conversion of natural gas. The two possible methods, direct conversion of methane and indirect conversion via synthesis gas, are discussed. The preparation of hydrocarbons that can be used as fuels and the production of building blocks for the petrochemical and chemical industries are both dealt with. The accent is placed on the key step in developing each process. Depending on the target product, this key step consists in working out a new catalytic system, changing reactor technology or engineering a less complex fractionation section.

  4. Some results on the fluorescence of gases excited by high-energy charged particles; Quelques resultats concernant la fluorescence de gaz excites par des particules chargees de grande energie

    Energy Technology Data Exchange (ETDEWEB)

    Koch, L.; Lesureur, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    The essential characteristics of rare gases for use as scintillators are as follows: a very brief period of luminescence, generally less than 10{sup -8} s; a linear response as a function of the energy lost by the nuclear particle in the gas, even in the case of strongly ionising particles (fission fragments). In the gaseous or condensed state therefore, they are of great interest in nuclear physics. (author) [French] Les caracteristiques essentielles des gaz rares en tant que scintillateurs sont: une duree de luminescence tres breve, inferieure a 10{sup -8} s en general; une reponse lineaire en fonction de l'energie perdue par la particule nucleaire dans le gaz, meme dans le cas de particules fortement ionisantes (fragments de fission). A l'etat gazeux ou condense, ils presentent donc un grand interet en physique nucleaire. (auteur)

  5. Natural gas and laundry: an efficient duo; Conference Cegibat: Gaz naturel et blanchisserie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    Cegibat, the information-recommendation agency of Gaz de France for building engineering professionals, has organized this conference about the use of natural gas in the laundry sector. This document summarizes the content of the different talks dealing with: the history and evolution of laundry activity, the energy consumption problem, the gas appliances (dryers) and their advantages, some testimonies in the health sector (hospitals), the regulatory aspects, the economic aspects (tariffs), Gaz de France energy diagnostic offer, and the testimony of a launderette. (J.S.)

  6. Cloning and Expression of Laccase Enzyme from B. pumilus strain GAZ23

    Directory of Open Access Journals (Sweden)

    Parvin Zamani

    2014-04-01

    Full Text Available Introduction: Laccases (benzene diol oxygen oxidoreductase: EC 1.10.3.2 are one of the multicopper oxidase family members that catalyze the oxidation of various phenolic compounds by using molecular oxygen Materials and methods Laccase gene was from strain GAZ23 amplified by cloning primers. PCR product cloned in the expression vector (pET21a and transferred to BL21 strain of E. coli and sequence analysis were carried out. Biochemical properties were investigated using common laccase substrates, 2,2ˊ-azino-bis(3-ethylbenzothioazolin-6-sulphonicacid ABTS. Results: 16S rRNA gene of strain GAZ23 isolated from Iran soils, showed high similarity to Bacillus pumilus (100%. The gene of the GAZ23 has an open reading frame composed of 1533 bases, which encode 510 amino acid residues. Discussion and conclusion: The laccase gene from GAZ23 shows 67% similarity with CotA from B. subtilis. The expression was performed under microaerobic condition and decreased temperature in order to obtain high amounts of soluble protein. This protein contains four histidine rich copper-binding domains.

  7. Methode particulaire multiniveaux pour la dynamique des gaz, application au calcul d'ecoulements multifluides

    OpenAIRE

    2006-01-01

    This work is devoted to the evaluation of the ability of a particle-mesh method, inspired from Vortex-In-Cell methods, to simulate gaz dynamics, especially multifluids. We firstly develop a particle-mesh method, associated with a conservative remeshing step, which is performed with high order interpolating kernels. We study theoretically and numerically this method. This analysis gives evidence of a strong relationship between the particle method and high order Lax-Wendroff-like finite differ...

  8. Aflatoxin in pistachio nuts used as ingredients in Gaz sweets produced in Isfahan, Iran.

    Science.gov (United States)

    Jahanmard, Elham; Azarani, Farzaneh; Sharifi, Mehran; Esfandiari, Zahra

    2014-01-01

    In Isfahan province of Iran, pistachio and almond are used specifically as ingredients to produce Gaz sweets, which are a typical product of Isfahan and exported to many countries. In this survey, 112 samples were gathered from different corresponding Gaz producers from 2007 to 2012 to evaluate the occurrence of aflatoxins (AF) in these products. Samples were analysed for AFB1, AFB2, AFG1 and AFG2 using immunoaffinity column clean-up (IC) and quantified by high-performance liquid chromatography (HPLC) with fluorescence detection. Among the samples analysed, AFB1 was detected in 13.4% of the samples above the maximum limit (ML) as set in Iran (5 µg/kg). Total AF (AFT) was above the ML in 9.8% of the samples. This study showed that full consideration is equally essential for nuts used as ingredients in special food products such as the Gaz sweets as for nuts for direct human consumption. It suggests a need for modifying the current trend of supervision.

  9. Oil and Gas Prospects in Egypt Recherches d'huile et de gaz en Égypte

    Directory of Open Access Journals (Sweden)

    El Ayouti M. K.

    2006-10-01

    Full Text Available Accumulations of oil were first known in Egypt since 1968, some ten years after the famous Drake well in Pennsylvania in August 1859. These oil accumulation were found as seepages in tunnels dug for extracting sulphur in the area of Gemsa on the West coast of the Gulf of Suez. Since that time exploration activites were conducted on and off throughout a long history of operations which witnessed the use of the latest developments in exploration tools and techniques. So far, the main oil province in Egypt is the Gulf of Suez Basin, where the bulk of oil reserve have been found. Other hydrocarbon provinces are the Nile Delta Basin, the Abu Gharadig Basin and the Alamein ridge, both in the Western Desert. Three important gas discoveries were made in the Nile Delta Basin two of which are offshore, in addition to other so for non commercial gas finds. In addition to the known oil and gas discoveries the exploration activities throughout that long period contributed volumenous geological and geophysical material and data which added appreciably to the geology of Egypt at large, and in particular to the petroleum geology of the country. The Gulf of Suez oil province displayed very favourable conditions for the generation and trapping of hydrocarbons in Miocene and Pre-Miocene pools though at the same time it displayed very complicated geological setting which renders the exploration work a difficult task. The Nile Delta Basin, on the otherhand, is a relatively very recently explored area. Accordingly, extensive exploration work is still needed in order to evaluate the hydrocarbon possibilities of that basin. So for, gas has been discovered at a number of locations in lower Pliocene-Miocene pools. Whether future work would prove that oil generation took place remains to be seen. The Western Desert did not yet display the required response with regards to the exploration work conducted till now. To date, only few small discoveries have been made with oil

  10. L'approvisionnement de l'Europe en gaz naturel à l'horizon 2010 European Natural Gas Supplies in Year 2010

    Directory of Open Access Journals (Sweden)

    Bauquis P. R.

    2006-11-01

    Full Text Available Cet article présente une prévision à l'horizon 2010 des besoins et de l'approvisionnement en gaz de l'Europe (Europe occidentale et orientale. Il montre qu'à cet horizon, tant la Norvège que l'Afrique du Nord augmenteront substantiellement leurs approvisionnements destinés à l'Europe, tandis que la plus forte augmentation en terme de volumes proviendra de l'ex-URSS et principalement de Russie. D'après cette analyse, la Russie serait capable de produire les volumes requis, même sans mettre en production les gisements de la péninsule de Yamal, tandis que les réserves gazières de la mer de Barentz russe (nommément le champ de Stockmanovskoye pourraient être développées d'ici 2005 ou même plus tôt. Durant la période 1995-2005, les quantités de gaz destinées à l'Europe en provenance du Moyen-Orient resteraient très limitées, alors qu'un premier gazoduc vers l'Europe pourrait entrer en opération vers 2010. Ultérieurement, le gaz du Moyen-Orient serait nécessaire pour maintenir un approvisionnement gazier de l'Europe en ligne avec les besoins européens. This article attempts to forecast european (Western and Eastern natural gas demand and gas supplies up to 2010. It shows that at such a horizon both Norway and North Africa will have substantially increased their gas exports supplied to the European markets while the largest increase in terms of additionnal volumes will comes the former USSR, essentially from Russia. According to this analysis, Russia would be able to produce the required volumes even without putting into production the Yamal Peninsula fields, while the Russian Barentz Sea gas reserves (namely Stockmanovskoye could be developed by 2005 or even earlier. During the period 1995-2005 only very limited gas exports to Europe would be required from the Middle East gas sources but the first gas pipeline between this region and Europe could begin to operate around 2010. Later on additionnal Middle East gas will be

  11. Synthesis Gas Purification Purification des gaz de synthèse

    Directory of Open Access Journals (Sweden)

    Chiche D.

    2013-10-01

    ce faire, une étape de gazéification convertit la charge carbonée en un gaz de synthèse (mélange de CO et H2, lequel, après ajustement du ratio H2/CO et élimination du CO2, subit ensuite la réaction de FischerTropsch. Les gaz de synthèse contiennent cependant de nombreuses impuretés qui nécessitent d’être éliminées afin d’éviter l’empoisonnement des catalyseurs Fischer-Tropsch. En raison de la grande variété de charges pouvant être mises en oeuvre, la composition des gaz de synthèse est susceptible de subir d’importantes variations, en particulier de part la nature des impuretés (éléments, spéciation présentes ainsi que leurs teneurs relatives. La composition des gaz de synthèse est également soumise à des spécifications extrêmement sévères en terme de pureté liées à l’importante sensibilité aux poisons des catalyseurs FT. Pour ces raisons, la purification des gaz de synthèse constitue un défi majeur pour le développement des procédés B-XTL. Dans cet article, nous présentons les principaux enjeux liés à la purification des gaz de synthèse. Les différents types d’impuretés pouvant être présentes dans les gaz de synthèse sont présentées. L’influence de la nature de la charge, des technologies de gazéification ainsi que des conditions opératoires associées sur la nature des impuretés et leurs teneurs relatives est discutée. Une attention particulière est portée au devenir des composés soufrés, azotés, des halogènes, métaux lourds et métaux de transition. Les principales technologies de purification des gaz de synthèse (adsorption, absorption, réactions catalytiques, etc. sont finalement décrites, ainsi que les défis associés.

  12. Preparation of radioactive gaseous standard; Preparation des etalons de gaz radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Blondel, M.; Phan, X.D. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    To prepare a radioactive gaseous standard it is necessary on the one hand to put into a sealed vial a well defined quantity of the gas concerned, and on the other hand to measure its specific activity. The determination of the quantity of gas which constitutes the standard implies accurate measurements of volume, temperature and pressure. To measure the specific activity, the method of compensated internal gas counters is used. The final accuracy on the specific activity of this standards is better than 0.8 per cent. The validity of the method used for the measurements was checked by measuring the specific activity of the tritiated hydrogen extracted from a tritiated-water standard. (authors) [French] La preparation d'un etalon gazeux radioactif necessite, d'une part, la mise en ampoule scellee d'une quantite bien determinee de ce gaz et, d'autre part, la mesure de son activite specifique. La determination de la quantite de gaz constituant l'etalon conduit a des mesures precises de volume, de temperature et de pression. La mesure de l'activite specifique est effectuee par la methode des compteurs a gaz interne compenses. L'exactitude finale sur l'activite specifique de ces etalons est meilleur que 0,8 pour cent. La validite de la methode de mesure est verifiee en mesurant l'activite specifique de l'hydrogene tritie extrait d'un etalon d'eau tritiee. (auteurs)

  13. Together on the same planet. Gaz de France and sustainable development in 2006; Ensemble sur la meme planete. Gaz de France et le developpement durable en 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This document presents the sustainable development policy of Gaz de France group. It identifies the challenges the group has to face in order to control the environmental impact of the Group's activities (exploration, production, procurement, re-gasification, transmission, storage, distribution, marketing and shares, services). The approach used is based on a voluntary commitment of the Group to dialogue and share current challenges with all its stakeholders, and to imagine other roads to development. The initiatives consist in clean production practices, development of renewable energy sources, energy conservation, investment in research, safety improvement, solidarity with underprivileged people, respect of local environment and of codes of conduct, accompanying local economic development and development of clean transport systems. (J.S.)

  14. EDF and Gaz de France reinforce their solidarity actions with clients in trouble; EDF et Gaz de France renforcent leurs actions de solidarite envers les clients en difficulte

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-31

    Electricite de France (EdF)and Gaz de France (GdF) public utility companies committed themselves to apply a volontarist solidarity policy with customers undergoing financial problems. An `energy solidarity charter` was signed in November 1996 between the ministry of housing, EdF and GdF. In 1998, EdF and GdF will participate to the employment of 500 young people in territorial organizations for giving help to such customers. This press dossier presents the poverty-precariousness conventions, commissions and funds devoted to customers in need, the convention signed between EdF and the national union of federations of council house organizations (Unfohlm) to improve the electric space heating in council flats, the convention signed between GdF and the Unfohlm for the renewal of individual or collective natural gas space heating installations, and the `energy keeping service` to ensure a minimum supply of electricity to customers in need. (J.S.)

  15. 2006 annual results: Gaz de France announces record-high results and exceeds its objectives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Paris, 13 March 2007 - In fiscal year 2006, Gaz de France had the best operational performance in its history. The Group confirms the strength of its business model, with sound Infrastructure business and sharp growth in Exploration - Production, Trading and Sales: - Net income, Group share: 2.3 billion euros; - EBITDA: 5.15 billion euros; - Dynamic dividend policy: 1.1 euro per share (+62%); - Investments at stepped-up pace: 4 billion euros (+38%); - Contribution of Group's international activities doubled in two years (39% of sales); - Many operational advances: strengthened operations, Exploration-Production, LNG Infrastructures and Electricity; - Major steps completed in merger project with Suez.

  16. 2006 annual results: Gaz de France announces record-high results and exceeds its objectives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Paris, 13 March 2007 - In fiscal year 2006, Gaz de France had the best operational performance in its history. The Group confirms the strength of its business model, with sound Infrastructure business and sharp growth in Exploration - Production, Trading and Sales: - Net income, Group share: 2.3 billion euros; - EBITDA: 5.15 billion euros; - Dynamic dividend policy: 1.1 euro per share (+62%); - Investments at stepped-up pace: 4 billion euros (+38%); - Contribution of Group's international activities doubled in two years (39% of sales); - Many operational advances: strengthened operations, Exploration-Production, LNG Infrastructures and Electricity; - Major steps completed in merger project with Suez.

  17. Le potentiel d’atténuation des gaz à effet de serre en productions bovines

    OpenAIRE

    Agabriel, Jacques; Dollé, J.-B.; Faverdin, Philippe; VAN DER WERF, Hayo

    2014-01-01

    L’élevage bovin est l’un des principaux contributeurs aux émissions de gaz à effet de serre (GES), le principal poste étant la fermentation entérique. En contrepartie, le stockage de carbone par les prairies et les haies compense de 25 à 30% des émissions nationales. L’élevage est également la phase qui domine l’empreinte carbone des produits lait et viande. L’analyse à l’échelle des exploitations fait apparaître une grande variabilité des niveaux d’émissions et de compensation et permet l’id...

  18. Les perspectives du gaz naturel dans le Monde World Natural Gas Prospects

    Directory of Open Access Journals (Sweden)

    Valais M.

    2006-11-01

    Full Text Available Dans un monde en quête de diversification énergétique, le gaz naturel apparaît comme une source d'énergie particulièrement attrayante. Par son abondance, sa facilité de substitution aux produits pétroliers dans une gamme très large d'usages, il pourrait assurément jouer un rôle beaucoup plus important dans la couverture des besoins énergétiques mondiaux. Toutefois, de nombreux obstacles semblent devoir ralentir sa progression. Cet article dégage les grands paramètres techniques et économiques qui devraient conditionner le développement de l'industrie du gaz dans le monde et présente des perspectives d'évolution de sa production et de son commerce international d'ici à la fin du siècle. For a world in search of energy diversification, natural gas is a particularly attractive source. Its abundance and its facility for being substituted for petroleum products over a wide range of uses should certainly mean that it will play a much more important rote in filling world energy needs. Nonetheless, many obstacles are hindering its progress. This article outlines the leading technical and economic parameters which should influence the development of the world gas industry, and the prospects for its production and international trade evolution between now and the end of the century.

  19. Evolution dans la gestion de la détection gaz

    CERN Document Server

    Bonthond, F

    1999-01-01

    Cet article présente l'interface graphique qui a été développée pour gérer d'une façon visuelle et globale la détection des gaz inflammables utilisés dans les expériences du hall EHN1 (NA49, NA56, tests pour ATLAS, CMS, Alice, etc.). A cet effet, on utilise des détecteurs catalytiques connectés à une centrale. Afin de retransmettre les alarmes à la salle de contrôle des pompiers, cette centrale est couplée à un automate programmable connecté au réseau Ethernet du CERN. Une liaison filaire entre l'automate et le synoptique câblé des alarmes de niveau 3 assure la redondance nécessaire à ce type d'alarmes. Le logiciel de contrôle LabView a été utilisé pour développer l'interface graphique. Elle permet de visualiser sur n'importe quel PC ou X-Terminal le taux de remplissage des bouteilles de gaz, la position des électrovannes ainsi que les asservissements qui pilotent lors d'une alarme, notamment les ventilations, les panneaux de signalisation et les arrêts d'urgence.

  20. L'effet de serre par le CO2 et les gaz traces Greenhouse Effect from CO2 and Trace Gases

    Directory of Open Access Journals (Sweden)

    Bertrand A.

    2006-11-01

    Full Text Available Selon une opinion assez répandue le CO2 et les gaz traces, produits par l'activité humaine depuis le début de la révolution industrielle (1850, principalement du fait de la combustion et de la déforestation, et progressivement accumulés dans l'atmosphère terrestre, pourraient par effet de serre provoquer au XXIe siècle un réchauffement de la Terre de quelques degrés. Les conséquences climatiques (fonte des glaces. . . en seraient désastreuses. Aussi avons-nous étudié les principaux paramètres impliqués par ce phénomène : nature de l'effet de serre, cycle du carbone, transfert de CO2 à l'échelle du globe, gaz traces, conséquences climatiques de l'effet de serre dû au CO2 et aux gaz traces. Nous en sommes arrivés aux conclusions suivantes : - La concentration de l'atmosphère en CO2 et en gaz traces augmente de façon exponentielle en absence de toute réglementation et cela parallèlement à une production humaine également exponentielle de ces mêmes substances. - On n'a encore décelé aucun accroissement de la température moyenne de la Terre dû à l'effet de serre, d'ailleurs depuis 1940 nous traversons une période de refroidissement. - L'activité humaine engendre aussi des effets antagonistes de refroidissement (action des poussières dans l'atmosphère. . . assez mal connus. - L'étude des climats anciens indique une succession régulière de périodes froides et chaudes, cela doit nous rassurer sur le risque d'une brusque modification irréversible du climat. - Cependant il est absolument nécessaire d'améliorer nos connaissances fondamentales sur les principaux facteurs réglant le climat terrestre (chimie de l'atmosphère, transfert océan-atmosphère. . . et éventuellement de restreindre la production de certains gaz traces (fréons en particulier. According to a fairly widespread opinion, CO2 and trace gases, which have been produced by human activity since the start of the industrial revolution (1850

  1. Les recherches menées par le Gaz de France dans le domaine de l'hydrogène Research on Hydrogen by Gaz de France

    Directory of Open Access Journals (Sweden)

    Donat G.

    2006-11-01

    Full Text Available Les besoins en énergie de l'humanité allant croissant et les ressources en combustibles de la Terre étant obligatoirement limitées, le temps viendra où la demande en hydrocarbures excédera la capacité mondiale de production; cette situation s'aggravera encore ultérieurement du fait de l'épuisement des réserves récupérables. Un recours massif aux énergies nucléaire et solaire semble donc indispensable et l'utilisation de l'hydrogène comme vecteur de ces énergies retient depuis quelques années l'attention, notamment en France où les ressources propres en pétrole sont faibles. Le Gaz de France a entrepris des recherches sur la production massive de l'hydrogène par décomposition de l'eau et vient de parvenir à des conclusions pessimistes quant à la compétitivité, par rapport à la voie électrolytique, de la filière utilisant des cycles thermochimiques. Par contre, l'électrolyse de l'eau offre des perspectives intéressantes à condition d'améliorer ses performances et son économie. D'autre part, des études concernant le stockage et le transport de l'hydrogène ont permis d'ores et déjà de tirer quelques conclusions dans ces domaines où les vecteurs gazeux disposent d'excellents atouts. With the increasing energy needs of mankind and the earth's necessarily limited resources of fuel, the time will come when the demand for hydrocarbons will exceed the world production capacity. This situation will subsequently get even worse becouse of the depletion of recoverable reserves. Massive recourse ta nuclear and solar energy thus appears indispensable, and the use of hydrogen as a vector for such energies has been under consideration for several years, especially in France where petroleum resources are very limited. Gaz de France has been doing research on the mass production of hydrogen by the decomposition of water and has just come ta rather pessimistic conclusions as ta the competitiveness of thermochemical processes in

  2. The reactions of magnesium and its alloys with moist gases at high temperatures; Les reactions du magnesium et de ses alliages avec les gaz humides aux temperatures elevees

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-02-15

    The kinetics and mechanisms of the reaction of pure or low alloyed magnesium with various gas saturated by water vapor: oxygen, argon, nitrogen, air, carbon dioxide, have been studied and compared in the temperature range 350-600 deg C. After picturing the large chemical reactivity of magnesium surface, the more or less properties of the oxide film, always made of magnesia, have been shown depending on the nature of the gas carrying water vapor; in fact, metal sublimation occurs the more easily as the surrounding atmosphere is less oxidizing. Moreover, an activation energy change is systematic, but at a temperature which depends also on the latter. In the case of the alloys, the linear oxidation rate is generally obtained only after short induction periods, parabolic in nature. Two possibilities of corrosion inhibition of magnesium by water vapor are then demonstrated and explained: either by a partial superficial fluoridation, or when the carrier gas is carbon dioxide. Also, the extreme conditions of oxidation were studied, that is the ignition processes that occur at a particular temperature in every gas mixture. Finally, it is tried to evolve the fundamental and practical significance of all the results. (author) [French] On a etudie et compare par voie thermogravimetrique, micrographique et radiocristallographique, les cinetiques et les mecanismes de reaction du magnesium et de certains de ses alliages avec diverses atmospheres saturees en vapeur d'eau: oxygene, argon, azote, air, gaz carbonique, dans un domaine de temperatures s'etendant de 350 a 600 deg C, Apres avoir illustre l'extreme sensibilite chimique de la surface du magnesium, on a tout d'abord montre que la valeur plus ou moins protectrice de la couche d'oxyde formee, pourtant toujours constituee de magnesie normale, depend de la nature du gaz porteur de la vapeur d'eau; en effet, la sublimation du metal intervient d'autant plus facilement que les atmospheres en

  3. Solar thermal and natural gas: an efficient complementarity; Solaire thermique et gaz naturel: une complementarite performante

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-10-01

    This document summarizes the content of a conference-debate organized by Cegibat, the information service of Gaz de France for building engineering professionals, about the complementarity between natural gas and solar thermal energies, in particular for the production of domestic hot water: 1 - the market of solar thermal energy in France (development, energy efficiency, different technical solutions, financial help, questions and answers with the public); 2 - the 'Dolce Vita' solar offer for individual houses (customers expectations, available techniques, fitter's testimony, questions and answers with the public); 3 - presentation of a combines solar system: the direct solar floor; 4 - the domestic solar hot water offer 'Dolce Vita'; 5 -testimonies; 6 - results warranty; 7 - conclusion. (J.S.)

  4. Lois cinétiques et calcul des réacteurs gaz-solide

    OpenAIRE

    Soustelle, Michel; Pijolat, Michèle

    2007-01-01

    National audience; Alors que les expressions de vitesse de réactions gaz – solide utilisées dans la simulation des réacteurs supposent que la vitesse à un instant donné est déterminée par la connaissance des valeurs des variables intensives (température, pression, composition de la phase gazeuse) et du degré d'avancement de la réaction à cet instant, on montre que cette propriété n'est pas toujours vraie. On montre qu'elle est mise en défaut, en particulier, lorsque les deux processus de germ...

  5. Les émissions de CO2 et autres gaz à effets de serre

    Directory of Open Access Journals (Sweden)

    François Durand-Dastès

    2010-07-01

    Full Text Available Cette note envisage les composantes explicatives des émissions de Gaz à effet de serre : coefficient d’émission par habitant et par unité monétaire de PNB, effets des masses de population et de production. La part de ces derniers est parfois curieusement sous estimée dans la littérature, et il semble nécessaire d’insister sur leur rôle majeur. Après une présentation cartographique et graphique de quelques données essentielles, on se livre à une expérimentation prospective à partir de ces données et des objectifs couramment mentionnés dans les accords internationaux. On cherche à en tirer quelques leçons.

  6. Les gaz à effet de serre en élevage bovin : évaluation et leviers d'action

    OpenAIRE

    Dollé, Jean-Baptiste; Agabriel, Jacques; Peyraud, Jean-Louis; Faverdin, Philippe; Manneville, Vincent; Raison, Christelle; Gac, Armelle; Le Gall, André

    2011-01-01

    Le contexte environnemental actuel, tant politique (objectifs de réduction des émissions de gaz à effet de serre) que sociétal (information du consommateur), nécessite de préciser les impacts de l'activité d'élevage bovin en matière de changement climatique. L'enjeu est de connaître précisément les niveaux d'émissions de gaz à effet de serre (GES) et de stockage de carbone, des différents modes de production. Pour cela, une évaluation basée sur la méthodologie de l'Analyse du Cycle de Vie (AC...

  7. Les perspectives du commerce international de gaz naturel d'ici 2000 The World Natural Gas Trade Outlook to 2000

    Directory of Open Access Journals (Sweden)

    Valais M.

    2006-11-01

    Full Text Available L'abondance des ressources gazières mondiales et l'excellence des qualités du gaz naturel, comme combustible et matière première pétrochimique, devraient lui permettre d'accroître sa pénétration sur les marchés énergétiques internationaux. Toutefois, la répartition géographique de ses réserves prouvées coïncide de moins en moins avec celle de sa consommation. En conséquence, la croissance du commerce international de gaz naturel apparaît comme une nécessité de plus en plus vitale du développement mondial de ses marchés. A partir d'une étude prospective menée au sein de l'Association Technique de l'industrie du Gaz en France (ATG, le présent mémoire se propose d'analyser les perspectives des échanges gaziers internationaux d'ici l'horizon 2000. The abundance of the world reserves of natural gas and the excellence of its qualities as a fuel and a petrochemical feedstock should enable natural gas to increase its penetration on international energy markets. However the geographic distribution of its proved reserves coincides less and less with the distribution of its consumption. Therefore, the increase in international gas trade appears more and more to be of vital necessity for the world development of its markets. On the basis of a study carried out within the Association Technique de l'industrie du Gaz en France (ATG, the present paper will attempt to analyse the outlook for international gas trade between now and the year 2000.

  8. New combustion, environment regulations: the answers for natural gas; Nouvelles reglementations, combustion, environnement: les reponses pour le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    Le Peltier-Marc, A. [Gaz de France (GDF), 75 - Paris (France)

    1997-12-31

    This paper reports on the point of view from Gaz de France (GdF) company concerning the potential consequences of the use of natural gas in combustion systems with respect to the new regulations about combustion and environment. Details concerning the measures relative to the limitation of pollutants in small combustion installations (2 - 20 MW) are given (chimney height, SO{sub x}, NO{sub x} and dusts content in exhaust gases). (J.S.)

  9. The Mooring Pattern Study for Q-Flex Type LNG Carriers Scheduled for Berthing at Ege Gaz Aliaga LNG Terminal

    Directory of Open Access Journals (Sweden)

    Selcuk Nas

    2014-12-01

    Full Text Available Ever growing energy industry requires larger quantities of LNG to be transported by bigger ships between terminals. Every day, new kind of large vessels created by new technologies, and these are used to trade around the globe. This is the dynamic change in shipping industry. But on the other hand these new vessels need to safely berth to existing terminals which we may accept as more static part of the trade. Thus this study born by the request of Ege Gaz Aliaga LNG Terminal management to determine if it is safe to berth to the terminal by a new breed of large LNG carrier type named as Q-Flex and Q-Max. Transas Bridge Simulator NTPRO 5000 series was used in this study for extensive experiments which had been simulated by the use of hook function. During the study, every force applied to mooring hooks and dolphins by the ship lines were divided into 3 dimensions and then measured by simulation experiments. With analysis of the data, required hook and dolphins strengths were determined for the safe mooring arrangements. Upon the completion of the study Ege Gaz Aliaga LNG Terminal became the first safe berth for Q-Flex type vessels in the Mediterranean and the Black Sea. And finally all experiments were confirmed with real life experience when the first Q-Flex type LNG carrier berthed to the Ege Gaz Aliaga LNG Terminal.

  10. Contribution to the chromatography of atmospheric gases (1963); Contribution a la chromatographie des gaz de l'air (1963)

    Energy Technology Data Exchange (ETDEWEB)

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

    1963-06-15

    In the first part, the author studies the gas-phase chromatographic separation of the atmospheric rare gases, of hydrogen, and of some gaseous compounds of carbon (CO, CO{sub 2}, CH{sub 4}) using inactive gases to obtain the most favourable operational conditions far this separation. In the second part, the optimum conditions for detecting non-active gases using an ionisation chamber and a {sup 239}Pu radioactive source emitting 5.15 MeV {alpha} particles are determined. (author) [French] Dans une premiere partie, l'auteur etudie la separation par chromatographie en phase gazeuse des gaz rares de l'air, de l'hydrogene, et de quelques composes gazeux du carbone (CO, CO{sub 2}, CH{sub 4}) en utilisant des gaz inactifs an vue d'obtenir les conditions experimenales les plus favorables en vue de cette separation. Dans une deuxieme partie, les conditions optimales de detection de gaz non actifs a l'aide d'une chambre d'ionisation, en utilisant comme source radioactive du {sup 239}Pu qui emet des particules {alpha} de 5,15 MeV, sont determinees. (auteur)

  11. Behaviour of rare gases in solids at high temperature; Comportement des gaz rares dans les solides a haute temperature

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    In this article a number of simple results regarding the solubility and displacement of rare gases in solids have been assembled. These results were obtained from elementary considerations on highly compressed gases and on dislocations. They provide a better understanding of the now fairly numerous experiments dealing with the swelling of irradiated fuels, this swelling being due to the presence of a high proportion of gases in the fission products. Finally, the chances of success of the various methods which may be devised to diminish the swelling are examined. (author) [French] Nous avons rassemble dans ce texte un certain nombre de resultats simples relatifs a la solubilite et au deplacement des gaz rares dans les solides. Ces resultats ont ete obtenus par des considerations elementaires sur les gaz tres comprimes et sur les dislocations. Ils permettent de mieux comprendre les experiences, maintenant assez nombreuses, qui ont trait au gonflement des combustibles irradies; gonflement qui est du a la presence d'une forte proportion de gaz dans les produits de fission. On examine finalement les chances de succes des differents moyens que l'on peut imaginer pour attenuer le gonflement. (auteur)

  12. Contribution to the study of the ionization and heating of gases by laser radiation; Contribution a l'etude de l'ionisation et du chauffage des gaz par le rayonnement d'un laser declenche

    Energy Technology Data Exchange (ETDEWEB)

    Veyrie, P. [Commissariat a l' Energie Atomique, Limeil-Brevannes (France). Centre d' Etudes

    1968-01-01

    The ionization and heating of gases by the concentrated radiation of a neodymium laser is studied. The power is 300 MW, the gas studied is primarily deuterium between 300 mm and 2280 mm. The first part concerns a certain number of experimental results on the absorption of the radiation and on changes produced in the plasma as a function of time. From these results are deduced a certain number of consequences, amongst which may be mentioned the definition of a pre-ionization threshold. These experimental results are interpreted in the second part. A calculation is made of the length of the period during which the electrons multiply up to when the absorption becomes measurable. The last phase corresponds to the hydrodynamics evolution, the calculations are compared with the experiments. The agreement between theory and experiment is satisfactory for the different phases. (author) [French] On etudie l'ionisation et le chauffage des gaz par le rayonnement concentre d'un laser au neodyme. La puissance est de 300 MW, le gaz etudie est principalement le deuterium entre 300 mm et 2280 mm. La premiere partie concerne un certain nombre de resultats experimentaux. Il s'agit de l'absorption du rayonnement et de l'evolution chronologique du plasma. De ces resultats on deduit un certain nombre de consequences parmi lesquelles il faut citer la definition d'un seuil de preionisation. Ces resultats experimentaux sont interpretes dans la deuxieme partie. On calcule la duree de la phase pendant laquelle se multiplient les electrons jusqu'a ce que l'absorption soit mesurable. La derniere phase correspond a l'evolution hydrodynamique. Les calculs sont confrontes avec l'experience. L'accord entre theorie et experience est satisfaisant pour les differentes phases. (auteur)

  13. Gas market is today strategical; Le marche du gaz est aujourd'hui strategique

    Energy Technology Data Exchange (ETDEWEB)

    Darricarrere, Y.L. [Total, 92 - Courbevoie (France)

    2006-07-01

    The energy market, and in particular the gas market, is today seething with excitement. In France, in Europe and in the rest of the world, the energy stakes are in the center of preoccupations. This article is an interview of Y.L. Darricarrere, general director of the gas and electricity division of Total group, who explains his opinions about the opening of European and French energy markets, presents the ambitions of Total group on these markets, and comments some recent events of the European energy scene: concentration between gas and electric utilities, the Suez and Gaz de France (GdF) project of merger, the risks linked with the coming in of national companies from producing countries, like Gazprom and Sonatrach, on the European market, the restriction of access of foreign companies to hydrocarbon reserves in Russia and Latin America (come back of the 'energy nationalism'), Total's policy for anticipating the increase of the world energy demand and the depletion of fossil fuel reserves. (J.S.)

  14. Adsorption de gaz sur les materiaux microporeux modelisation, thermodynamique et applications

    Science.gov (United States)

    Richard, Marc-Andre

    2009-12-01

    Nos travaux sur l'adsorption de gaz dans les materiaux microporeux s'inscrivent dans le cadre des recherches visant a augmenter l'efficacite du stockage de l'hydrogene a bord des vehicules. Notre objectif etait d'etudier la possibilite d'utiliser l'adsorption afin d'ameliorer l'efficacite de la liquefaction de l'hydrogene des systemes a petite echelle. Nous avons egalement evalue les performances d'un systeme de stockage cryogenique de l'hydrogene base sur la physisorption. Comme nous avons affaire a des plages de temperatures particulierement etendues et a de hautes pressions dans la region supercritique du gaz, nous avons du commencer par travailler sur la modelisation et la thermodynamique de l'adsorption. La representation de la quantite de gaz adsorbee en fonction de la temperature et de la pression par un modele semi-empirique est un outil utile pour determiner la masse de gaz adsorbee dans un systeme mais egalement pour calculer les effets thermiques lies a l'adsorption. Nous avons adapte le modele Dubinin-Astakhov (D-A) pour modeliser des isothermes d'adsorption d'hydrogene, d'azote et de methane sur du charbon actif a haute pression et sur une grande plage de temperatures supercritiques en considerant un volume d'adsorption invariant. Avec cinq parametres de regression (incluant le volume d'adsorption Va), le modele que nous avons developpe permet de tres bien representer des isothermes experimentales d'adsorption d'hydrogene (de 30 a 293 K, jusqu'a 6 MPa), d'azote (de 93 a 298 K, jusqu'a 6 MPa) et de methane (de 243 a 333 K, jusqu'a 9 MPa) sur le charbon actif. Nous avons calcule l'energie interne de la phase adsorbee a partir du modele en nous servant de la thermodynamique des solutions sans negliger le volume d'adsorption. Par la suite, nous avons presente les equations de conservation de la niasse et de l'energie pour un systeme d'adsorption et valide notre demarche en comparant des simulations et des tests d'adsorption et de desorption. En plus de l

  15. Gas transport through porous media; Sur le transport des gaz a travers les milieux poreux

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-06-01

    In the first part of this work we derive a rigorous transport theory for a mixture of gases passing through a bed of spheres, when the temperature is uniform. We solve the Boltzmann equation, putting boundary conditions in the solution. Two different methods are used, according to the nature of the flow. The second part deals with the experimental work: measurements of permeability, of separation and of interdiffusion. In the last part, with the help of the new theory presented here, we are for the first time able to explain all the experimental data. (author) [French] Dans la premiere partie de ce travail nous developpons une theorie rigoureuse du transport d'un melange de gaz a travers un lit de spheres, quand la temperature est uniforme. Nous integrons l'equation de Boltzmann en introduisant des conditions aux limites dans la solution. Nous utilisons deux methodes differentes selon le regime d'ecoulement. La seconde partie est consacree a l'etude experimentale: mesures de permeametrie, de separation et d'interdiffusion. Dans la derniere partie, a l'aide de la nouvelle theorie developpee ici, nous expliquons tous les resultats experimentaux, ce qui n'avait pas ete fait jusque la. (auteur)

  16. Les techniques de séparation de gaz par membranes Gas Separation Techniques by Membranes

    Directory of Open Access Journals (Sweden)

    Avrillon R.

    2006-11-01

    Full Text Available Deux types de membranes peuvent être utilisés pour la séparation des gaz. Les unes sont poreuses et séparent les gaz sur la base de leur masse moléculaire selon un mécanisme de diffusion de Knudsen dans des micropores. Les facteurs de séparation obtenus sont généralement trop faibles pour présenter un intérêt industriel. Les autres, appelées membranes non poreuses, mettent en oeuvre un mécanisme de dissolution-diffusion des gaz dans une fine couche de polymère dénuée de toute porosité. C'est de ces dernières que nous allons parler. Commencé il y a une vingtaine d'années, le développement de ce type de membranes a conduit aux premières applications industrielles en 1979 avec l'introduction par Monsanto des séparateurs PRISM pour la récupération d'hydrogène à partir de différents gaz de raffinerie et de pétrochimie. Après des débuts modestes par suite de la compétition avec des technologies éprouvées comme la cryogénie, l'adsorption et l'absorption, la perméation gazeuse est en train de conquérir sa place parmi les techniques de séparation de gaz. Elle est aujourd'hui l'une des techniques membranaires présentant le plus fort taux de progression (30 % par an. Après un rappel des principes de base de la perméation gazeuse on abordera successivement les points suivants : - le choix du polymère constituant la couche séparatrice, - l'élaboration des membranes à structure asymétrique présentant une peau dense et fine, - les principales applications industrielles. Cela permettra de mettre en évidence les avantages et les limitations actuelles de la perméation gazeuse et de souligner les différents domaines où les efforts de R et D peuvent amener des progrès significatifs. Principle of Gas permeation - Gas permeation is a technique for fractionating gas mixtures by using nonporous polymer membranes having a selective permeability to gas according to a dissolution-diffusion mechanism. Gas is made to pass

  17. Ecoulements intermittents de gaz et de liquide en conduite verticale Intermittent Gas and Liquid Flows in a Vertical Pipe.

    Directory of Open Access Journals (Sweden)

    Line A.

    2006-11-01

    Full Text Available Le modèle présenté ici permet la pré-détermination du gradient de pression, du taux global de gaz, et de grandeurs caractéristiques de l'intermittence, dans un écoulement à poches et bouchons en conduite verticale. L'écriture des lois de conservation en moyenne phasique conditionnelle conduit à la définition d'une cellule moyenne équivalente. La fermeture du modèle est assurée par des lois de contrainte de cisaillement film-paroi, film-poche, bouchon-paroi, par une loi d'arrachage du gaz au culot de la poche, une loi de glissement du gaz dans les bouchons et par une loi de la vitesse moyenne de propagation des fronts de poches. Le calibrage et la qualification du modèle s'appuient sur deux banques de données, dont l'une a été obtenue avec des fluides pétroliers dans des conditions proches des situations industrielles (boucle diphasique de Boussens. The model described here can be used to predetermine the pressure gradient, the overall gas rate and the characteristic intermittence magnitudes in pocket and slug flow in a vertical pipe. The way governing equations in the conditional phase average are written defines an equivalent average cell. The model is closed by film/wall, film/pocket and slug/wall shear-stress laws, by a pulloff law for the gas at the bottom of the pocket, a slippage law for the gas in the slugs, and a mean propagation velocity law for the pocket fronts. The calibration and qualification of the model are based on two data banks, one of which contains data on petroleum fluids under conditions close to industrial situations (two-phase loop at Boussens.

  18. Energy efficiency in buildings with the natural gas; L'efficacite energetique dans le batiment avec le gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-11-01

    This document summarizes the content of a conference-debate organized by Cegibat, the information service of Gaz de France (GdF) for building engineering professionals, about the improvement of the energy efficiency of buildings thanks to the use of natural gas: 1 - the environmental stakes of energy savings in buildings; 2 -evolution of the regulatory context; 3 - the R and D answers of appliance manufacturers; 4 - GdF's choices and commitments; 5 - efficiency analysis (technical inspections and audits); 6 - efficiency maintenance (renovation and follow-up); 7 - conclusions. (J.S.)

  19. La modelisation mathematique dans l'enseignement de la chimie des gaz a des eleves de la cinquieme annee du secondaire

    Science.gov (United States)

    Gauthier, Diane

    Les problemes d'enseignement de la chimie des gaz parfaits sont donc importants. Si plusieurs etudes ont ete realisees dans le but d'identifier et d'interpreter ces problemes, aucune recherche, a notre connaissance, n'a ete realisee sur l'enseignement des lois sur les gaz parfaits. Notre recherche sur l'enseignement est donc pionniere. Elle a pour objectif general de construire et d'analyser une sequence d'enseignement de la chimie des gaz comportant diverses situations de modelisation mathematique des conduites des gaz. Les principaux objectifs specifiques sont les suivants: (1) identifier et caracteriser les situations qui provoquent une evolution des conceptions naives des eleves, evolution vers des connaissances plus adequate sur les gaz; (2) identifier et caractEriser les situations qui provoquent une evolution des connaissances mathematiques des eleves leur permettant d'interpreter convenablement les resultats des experiences, d'eprouver leurs conceptions, de donner un sens aux notions et aux relations impliquees dans les lois des gaz parfaits, lois de Boyle-Mariotte et Gay-Lussac. Une sequence d'enseignement comportant huit situations est d'eleves de secondaire V. La construction de ces situations est orientee par les recherches sur les conceptions naives des eleves, par les etudes sur l'evolution historique des conceptions sur les gaz et des pratiques scientifiques, ainsi que par les etudes theoriques et empiriques realisees en didactique des sciences et des mathematiques. La methodologie de l'ingenierie didactique (Artigue, 1998) qui constitue une application de la theorie des situations didactiques (Brousseau, 1986) est utilisee dans la construction et l'analyse des situations d'enseignement. Une analyse a priori de chacune des situations d'enseignement est effectuee; elle a pour but dexpliquer les choix des taches qui font partie des situations et de preciser la gestion didactique des situations. Diverses situations d'enseignement de la chimie ont ainsi

  20. Excitations Solitoniques Du Gaz D'electrons Bidimensionnel Dans Un Double Puits Quantique En Champ Magnetique (french Text)

    CERN Document Server

    Doiron, C

    2005-01-01

    L'état fondamental du gaz d'électrons bidimensionnel (GE2D) dans un double puits quantique (DPQ) en champ magnétique à remplissage ν = 4N + 1 est, pour une certaine gamme de distances interpuits, une onde de densité de charge cohérente. Cette phase présente des canaux cohérents unidimensionnels où l'électron est totalement délocalisé dans les deux puits. Il a été proposé que ces canaux puissent jouer un rôle important sur les propriétés de transport du gaz électronique dans la phase onde de densité de charge cohérente en permettant l'existence d'excitations topologiques chargées de faible énergie, des solitons de pseudospin. Dans ce mémoire, on présente une vérification théorique de la pertinence de ces excitati...

  1. A Geochemical Approach for Monitoring a CO2 Pilot Site: Rousse, France. A Major gases, CO2-Carbon Isotopes and Noble Gases Combined Approach Une méthode géochimique pour la surveillance d’un site pilote de stockage de CO2 : Rousse, France. Approche combinant les gaz majeurs, l’isotopie du carbone du CO2 et les gaz rares

    Directory of Open Access Journals (Sweden)

    Garcia B.

    2012-02-01

    storage pilot suggest that noble gas compositions produced by oxyfuel process are sufficiently exotic compared to compositions found in nature (reservoir, aquifer and air to be directly used as tracers of the injected CO2, and to detect and quantify leaks at soil and aquifer levels. Ce papier presente la caracterisation geochimique des differents gaz, naturels et anthropogeniques, impliques dans un pilote de stockage de CO2 en champ de gaz naturel appauvri (Rousse, France. Dans ce pilote, le CO2 est produit par oxycombustion d’un gaz naturel transforme en gaz domestique a l’usine de Lacq. Ce CO2 est transporte dans un pipeline de 30 km de longueur jusqu’au reservoir de gaz appauvri de Rousse. Les gaz produits a Rousse avant injection de CO2, le gaz commercial de Lacq et le CO2 resultant de l’oxycombustion ont ete echantillonnes, ainsi que les gaz situes dans un puits de surveillance (a une profondeur de 45 m et les gaz du sol situes au voisinage de Rousse. Pour tous ces echantillons, la composition en gaz majeurs, la signature isotopique du carbone ainsi que l’abondance et signature isotopique des gaz rares ont ete determinees. Les compositions gazeuses du gaz naturel de Rousse sont comparables a celle du gaz domestique de Lacq avec le methane comme compose principal et la fraction C2-C5 et CO2 comme gaz residuels. Les gaz des sols refletent typiquement des melanges entre l’air (pole pur et le CO2 d’origine biogenique (avec des teneurs maximales de l’ordre de 9-10 %, tandis que les gaz presents dans le puits de monitoring refletent typiquement la composition de l’air sans exces de CO2. Le gaz de Rousse et le gaz domestique du site de Lacq ont une composition isotopique δ13CCH4 egale a –41,0 ‰ et –43,0 ‰ respectivement. Le CO2 injecte sur Rousse a une composition isotopique δ13CCO2 egale a –40,0 ‰ a la sortie de la chambre d’oxycombustion, tandis que la composition isotopique δ13CCO2 des gaz des sols est comprise entre –15 et –25

  2. On Mist Formation in Natural Gas Sur la formation de buée dans le gaz naturel

    Directory of Open Access Journals (Sweden)

    Muitjens M. J. E. H.

    2006-11-01

    Full Text Available Mist formation that occurs during production, handling, and transport of natural gas is shown to be the result of non equilibrium thermodynamic processes. A simple analysis is presented of these nucleation and droplet growth phenomena in natural gas, and an estimate is given of the rate at which droplets are formed for typical process conditions. A model of droplet growth due to condensation is presented. The nucleation and condensation behaviour of two samples of a natural gas is investigated in a Wilson expansion cloud chamber for the initial pressure range of 5 to 50 bar and initial temperatures of 294-297 K (21-24°C. For a cooling rate of about 1 K/ms, a typical undercooling at the onset of condensation is found of 32 ý 3K and 60 ý 5K respectively for the two samples, which emphasizes the importance of non-equilibrium effects. La formation de buée au cours de la production, du maniement et du transport de gaz naturel est le résultat d'un déséquilibre thermodynamique. Une analyse simple de la nucléation et de la croissance des gouttelettes dans le gaz naturel est présentée. Une estimation du taux de formation dans de tels processus ainsi qu'un modèle de croissance des gouttelettes par condensation sont alors établis. La nucléation et la condensation de deux échantillons de gaz naturel ont été examinées dans une chambre d'expansion de Wilson dont les gammes de pression et de température initiales sont respectivement de 5 à 10 bar et de 294 à 297 K (21-24°C. Pour un taux de refroidissement de 1 K/ms, les valeurs de sous-refroidissement trouvées au moment de l'initialisation de la condensation sont respectivement pour les deux échantillons 32 ý 3K et 60 ý 5K, ce qui souligne l'importance des effets de déséquilibre.

  3. Effet de l'interaction coulombienne sur la localisation d'Anderson dans le gaz bidimensionnel d'électrons

    Science.gov (United States)

    Fleury, G.

    2010-09-01

    Nous étudions l’effet des interactions coulombiennes sur la localisation d’Anderson dans le gaz bidimensionnel d’électrons désordonné. L’objectif est de statuer sur la question de l’existence de métaux à deux dimensions. En l’absence d’interaction, la théorie d’échelle de la localisation prédit qu’un désordre infinitésimal suffit à localiser la fonction d’onde électronique et donc à rendre le système isolant à température nulle (Abrahams et al., 1979). Dans certaines limites extrêmes, les interactions peuvent être prises en compte et l’on aboutit également à un état isolant. Cependant, aucune théorie analytique ne permet de traiter le régime quantique non-perturbatif où désordre et interaction sont intermédiaires. Expérimentalement, il est possible de l’explorer dans des échantillons de haute mobilité et basse densité. Depuis 1994, des comportements métalliques inexpliqués y ont été observés (Kravchenko et al., 1994). Nous avons mis au point une méthode numérique permettant d’étudier le problème couplé de la localisation d’Anderson en présence d’interaction. Cette méthode mêle Monte Carlo quantique à température nulle et théorie d’échelle pour la conductance de Thouless. Nous trouvons que la théorie d’échelle de la localisation est préservée en présence d’interaction et donc que le gaz bidimensionnel, même corrélé, est isolant à température nulle. Nos résultats montrent de plus que les interactions délocalisent le gaz bidimensionnel et que cet effet de délocalisation est accru en présence de dégénérescence de vallées. Ils nous permettent de proposer un mécanisme simple rendant compte des principales caractéristiques des comportements métalliques observés expérimentalement.

  4. Désulfuration sélective du gaz soutiré d'un stockage souterrain Selective Desulfurization of Gas Withdrawn from an Underground Storage Facility

    Directory of Open Access Journals (Sweden)

    Jaubertou G.

    2006-11-01

    Full Text Available La présence d'H2S constatée dès les premiers soutirages de gaz au stockage souterrain en nappe aquifère de Chémery avait nécessité la mise en place d'unités de désulfuration. Le gaz injecté étant exempt de gaz carbonique, le procédé par voie liquide utilisant la monoéthanolamine avait été retenu. Depuis 1977, le gaz injecté contenant des quantités appréciables de gaz carbonique a rendu inutilisable ce procédé. Parallèlement à l'injection de ce composé acide, la production d'H2S a fortement augmenté. La mise en oeuvre d'une amine sélective (MDEA a permis d'éliminer les composés soufrés en laissant pratiquement inchangée la composition du gaz chargé en C02. Les installations existantes ont pu être conservées, la banalisation des circuits facilitant l'utilisation de cette nouvelle amine. La communication présente les études et essais réalisés ainsi que les résultats d'exploitation qui se sont révélés particulièrement intéressants tant au point de vue technique qu'économique The presence of H2S in the first gas withdrawn from the underground storage aquifer at Chémery, France, required the installation of desulfurization units. Since there was no carton dioxide in the injected gas, a liquid process using monoethanolamine was selected. This process has become unusable since 1977 because the injected gas contains appreciable amounts of carton dioxide. At the same time as the injection of this acid compound, the production of H2S has considerably increased. A selective amine (MDEA was used tg eliminate the sulfur-containing compounds while leaving the composition of the C02-containing gas almost unchanged. The existing installations have been maintained as the result of the standardizing of the circuits for this new amine. This article describes the research and tests performed as well as the operational results which have turned out to be particularly intersting from both the technical and economic stand

  5. No 3017. Resolution proposal aiming at creating an inquiry commission relative to the project of merger between Gaz de France and Suez, to the conditions of its preparation and announcement and to the consequences of Gaz de France privatization on users and on the energy market balance; N. 3017. Proposition de resolution tendant a la creation d'une commission d'enquete relative au projet de fusion entre Gaz de France et Suez, aux conditions de sa preparation et de son annonce et aux consequences de la privatisation de Gaz de France pour les usagers et l'equilibre du marche de l'energie

    Energy Technology Data Exchange (ETDEWEB)

    Balligand, J.P.; Ayrault, J.M.; Hollande, F.; Besson, E.; Migaud, D.; Emmanuelli, H.; Brottes, F.; Bataille, Ch.; Ducout, P.; Gaubert, J.; Habib, D

    2006-04-15

    On February 25, 2006, the French government took the decision of merging together Gaz de France and Suez energy companies as an answer to Enel's project of takeover bid on Suez. This document wonders about: the real motivations of Gaz de France (the French gas utility) privatization, the possible intervention of public authorities in Enel and Veolia companies project of controlling the Suez group, the governing way of the share-holding government and the preservation of its industrial interests, and the consequences for consumers. Therefore, the creation of a parliamentary inquiry commission is requested to shade light on these different points and to give notice of any bad practices in this affair. (J.S.)

  6. Natural gas air conditioning in the tertiary sector. Ambitions, realizations and tools; Climatisation au gaz naturel dans le tertiaire. Ambitions, realisations et outils

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-04-01

    This meeting, organized by the research center of Gaz de France (Cegibat), makes a status of the market of natural gas air conditioning in office and public buildings: experience feedback, improvements of the technology, available tools. After a brief presentation of the status and perspectives of this market in France, the representatives of different companies involved in the fitting of natural gas air conditioning systems present their point of view about this technology. A last part presents the 'climogaz.com' tool launched by Gaz de France. It consists in a web site devoted to the share of knowledge and experience about this technology between professionals and applied to hotels, swimming pools, office buildings, food trade and other trades. (J.S.)

  7. Fick Sistemini Kullanarak Dört Bilesenli Su-Gaz Degisim Reaksiyonunun Difüzyon Katsayılarının Teoriksel İncelenmesi

    Directory of Open Access Journals (Sweden)

    Murat ÖZTÜRK

    2009-04-01

    Full Text Available Bu çalısmada; izotermik kosulu saglanmıs, ideal boru reaktörde, ekzoterm, heterojen katalitik bir gaz reaksiyonu olan su-gaz degisim reaksiyonu model olarak alınarak dört bilesenli gaz difüzyonu incelenmistir. T=523 oK ve 623 oK'de dört bilesene ait on iki adet poliner difüzyon katsayısı Fick sistemi için elde edilmistir. Teoriksel olarak hesaplanan poliner difüzyon katsayıları CO mol sayısının (x1 degisim miktarına baglı olarak diyagramlar halinde sunulmustur. Bu diyagramlardan altı tanesinin karbonmonoksit mol sayısı azalınca arttıgı, diger altı tanesinin ise azaldıgı görülmüstür. Ayrıca, artan reaksiyon sıcaklıgı ile beraber difüzyon katsayılarının degerlerinde artıs oldugu tespit edilmistir.

  8. Gaz de France first quarter 2007 sales: an 11 per cent drop due to an exceptionally warm winter: a 1.3 per cent increase on an average-climate basis. Non-audited IFRS data

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Paris, May 14 2007 - For the first quarter 2007, Gaz de France Group posted euro 9,053 million in consolidated sales. This 11 per cent decrease on the same period in 2006 is a direct result of the extremely warm weather conditions in France and Europe this winter. In contrast, under average climate conditions sales improved by 1.3 per cent. In France, where the winter of 2006/2007 was the warmest in fifty years, sales were impacted by 18 billion kWh in the quarter compared to a quarter with average-climate conditions and 32 billion kWh compared to the first quarter 2006 which, in contrast, was colder than normal. The impact of the weather had similar effects on sales outside France. The highly unusual weather conditions also had an indirect impact on the market and, consequently, on both gas production and the arbitrage activities. Not withstanding these effects, the Group continued to consolidate its position in foreign markets, with sales outside France reaching euro 3,341 million. The share of sales outside France increased by 3 points in the first quarter of 2007 versus first quarter 2006 to 37 per cent as at end March 2007. The group reiterates the 2007 financial objective as presented at the full year 2006 results: '2007 will be a year of consolidation and the EBITDA should be in line with that of 2006'.

  9. Étude et modélisation du comportement d'un écoulement annulaire dispersé : application à la mesure de débit de gaz humide à l'aide d'un débitmètre à Venturi

    OpenAIRE

    Lupeau, Alexandre

    2005-01-01

    Le travail proposé a pour but d'apporter des éléments de compréhension sur le comportement d’un débitmètre gaz sec de type Venturi en configuration d'écoulement annulaire dispersé (gaz humide). Ce type d'écoulement se présente sous la forme d’un mélange gaz/liquide avec des fractions volumiques de gaz supérieures à 99%. Le liquide se répartit à l'intérieur des conduites sous forme de gouttes et d'un film ruisselant sur les parois. Ce sont les interactions entre le gaz et ces différents constitu...

  10. Etude du déplacement de l'huile par le gaz Analysis of Oil Displacement by Gas

    Directory of Open Access Journals (Sweden)

    Delclaud J.

    2006-11-01

    Full Text Available Les ingénieurs « réservoir u prévoient avec beaucoup de difficultés l'exploitation des gisements en utilisant les relations perméabilités relatives-saturations fournies par les laboratoires. Ceci amène à se demander si le concept est valide en écoulement transitoire, si les mesures sont effectuées selon des procédures convenables, si la relation statique entre la pression capillaire et la saturation est conservée en régime variable, si enfin la méconnaissance des lois de combinaison de ces fonctions n'est pas la cause de l'insatisfaction des ingénieurs. Le travail présenté ici traite des trois premiers points. Deux séries d'expériences sont réalisées à cet effet : - d'une part, des expériences de déplacement de l'huile par le gaz, où l'on s'intéresse à l'établissement et à la caractérisation de phénomènes pseudo-stationnaires. Les échantillons poreux choisis sont de faibles dimensions. Ils permettent ainsi de réduire la durée des périodes transitoires; - d'autre part, des expériences de déplacement sur des échantillons homogènes de grandes dimensions où l'on étudie les phénomènes transitoires. On mesure, tout au long du massif, la pression dans les deux phases et la saturation. Les perméabilités relatives sont calculées en tout point et à tout instant, à partir des équations de continuité. II ressort de ces travaux que la relation perméabilité relative-saturation est la même en tout point du milieu poreux, tout au long de l'écoulement transitoire, qu'elle ne dépend pas de la vitesse d'écoulement et que la relation pression capillaire-saturation coïncide avec celle établie par la méthode des états restaurés. La validité du concept en écoulement transitoire est donc prouvée. La méthode de WELGE, JOHNSON, BOSSLER et NAUMANN conduit à des résultats différents de ceux obtenus. On montre, pour expliquer ces écarts, que les hypothèses théoriques de cette méthode sont

  11. La gazéification souterraine profonde du charbon en France. L'expérience de Bruay-en-Artois Underground Coal Gasification At Great Depth. The French Field Test of Bruay-En-Artois

    OpenAIRE

    Gadelle C.; Lessi J.; Sarda J. P.

    2006-01-01

    Le projet français de gazéification souterraine du charbon, dont l'objectif à terme est la production d'un substitut de gaz naturel, vise la gazéification de veines de charbon de faible épaisseur, situées à grande profondeur et non exploitables par les méthodes classiques. De nombreuses difficultés sont liées à la profondeur (plus de 1000 m), en particulier la nécessité d'opérer sous pression élevée dans un charbon très peu perméable. Les premiers essais, effectués sur un pilote à 1200 m de l...

  12. Procédé de fabrication de Gaz Naturel de Synthèse par couplage d'une méthanation avec une électrolyse de vapeur d'eau à haute température

    OpenAIRE

    De Saint Jean, Myriam; Lacroix, Vincent; Baurens, Pierre; Bouallou, Chakib

    2013-01-01

    National audience; Le procédé présenté ici est un procédé de type Power-to-Gas dont l'objectif est de produire un gaz de synthèse injectable sur les réseaux de gaz naturel, en couplant une électrolyse de vapeur d'eau à haute température à cellule à oxyde solide (Solid Oxide Electrolysis Cell) et une hydrogénation de CO2 afin de produire du méthane, composant majeur du gaz naturel de synthèse. La simulation de ce procédé est réalisée avec le logiciel de simulation ProSim Plus 3® et des modèles...

  13. Unconventional Gas Resources in the Paleozoic of Central Europe Ressources de gaz non conventionnels dans le Paléozoïque de l’Europe Centrale

    Directory of Open Access Journals (Sweden)

    Littke R.

    2011-05-01

    Full Text Available Whereas gas production from unconventional reserves has greatly increased over the past decades, there is still a largely unexplored potential in the Paleozoic of Central Europe. For this area, the paper summarizes some important aspects of the geology of tight sandstone gas reservoirs, gas shales and coalbed methane. Tight sandstones with low permeabilities are especially present in the Permian (Rotliegend Formation of The Netherlands and northern Germany, but also in the underlying Carboniferous. There is already active production from some of these reservoirs. Further development greatly depends on understanding of gas charge as well as the regional distribution of porosity and permeability which in turn depend on facies and diagenesis. In contrast exploration for gas shales is just at the very beginning. Whereas Mesozoic shales in the southern Lower Saxony Basin have to be regarded as prime targets due to thickness, maturity and organic matter content, there are additional targets in the Mississippian, but also in older rocks. Currently an international gas shale research programme (Gas shales in Europe, GASH gathers relevant data for these units. Coalbed methane exploration started already about 20 years ago in the Ruhr Basin, but was not successful at that time due to small flow rates. On the other hand, production from abandoned coal mines provided substantial amounts of gas. Due to the abundance of coal seams and the suitable maturity conditions and gas contents, there is a high potential for future substantial coalbed methane in the area. Alors que l’extraction du gaz naturel des gisements non conventionnels a fortement augmenté ces dernières dizaines d’années, un large potentiel de ressources reste inexploré dans les couches paléozoïques de l’Europe Centrale. Cet article présente, pour cette région, quelques aspects importants de la géologie des grès de faible perméabilité (tight gas sands, des gaz de schiste (gas

  14. Experimental contribution to the study of gas bearings; Contribution experimentale a l'etude des paliers a gaz

    Energy Technology Data Exchange (ETDEWEB)

    Gobert, G

    1962-07-01

    Developments for gas-lubricated bearings are discussed. The study of how the fluid film behaves compared to what one can expect is discussed. Various devices are described which have allowed us to go up to peripheral velocity greater than 400 m/s, leading to rotational speed of several thousand revolutions per second. This is obtained by using an automatic setting for the distance between fixed and rotating walls. (author) [French] Le present travail debute par un apercu de l'etat actuel des connaissances sur le processus de la lubrification, notamment sur les paliers a lubrification par gaz. Apres une analyse effectuee au moyen des recentes theories de R. Comolet sur le film fluide entre disques paralleles, nous decrivons des machines dont les charges axiales et radiales specialement etudiees ont permis, au moyen d'un reglage automatique des jeux entre parois fixes et parois tournantes, d'atteindre des vitesses peripheriques superieures a 400 m/s correspondant a des vitesses de plusieurs milliers de tours par seconde. (auteur)

  15. Natural Gas Potential of the United States Ressources potentielles en gaz naturel des États Unis

    Directory of Open Access Journals (Sweden)

    Kent H. C.

    2006-10-01

    Full Text Available Updated resource estimates of the natural gas potential for the United States using the results of developments through 1978 are now available. The estimated resources include 200 trillion cubic feet of proved reserves and 1,019 trillion cubic feet of potential resources from conventional reservoirs. More than 50% of the proved reserves are located in three principal areas: South Louisiana; Alaska; and the Mid-Continent region of Oklahoma, Kansas and the Texas Panhandle. Approximately 50% of the potential resources are located in four areas: the northern and central Rocky Mountain states, the Mid-Continent region, offshore Alaska, and offshore Louisiana. Projections indicate that these potential sources, including Alaska, can continue to provide through the year 2000 approximately the same amount of gas, on an annual basis, as is currently being produced in the US. Slnce 1968, proved reserves of gas in the lower 48 states have declined. Part of the decline can be attributed to the decline in drilling activity from 1956 through 1972, but location and depth of wells are also important. About 14% of oil wells drilled in the United States in 1978 were drilled as new field wildcats and only 4% of the successful gas wells completed were drilled as new field wildcats. In 1977, 80% of the wells were completed in areas and at depths where only 22% of the natural gas resource potential is believed to exist. Clearly, the emphasis on exploration and drilling must be redirected toward those areas of greater gas resource potential in order to meet future needs. On dispose maintenant d'estimation à jour des ressources potentielles en gaz naturel pour les États-Unis utilisant les résultats des développements en 1978. Les ressources estimées comprennent 200 Tcf (± 5,7 Tm3 de réserves prouvées et 1,019 Tcf (± 29 Tm3 de ressources potentielles pour les réservoirs conventionnels. Plus de 50 % des réserves prouvées se situent dans trois secteurs

  16. Étude des équilibres thermodynamiques des réactions de gazéification en vue de l'optimisation du rapport vapeur/comburant injecté dans un gazogène souterrain Study of Thermodynamic Equilibria in Gasification Reactions So As to Optimise the Steam/Oxidizer Ratio Injected Into an Underground Gas Generator

    OpenAIRE

    Pirard J. P.

    2006-01-01

    Le but de cette étude est de déterminer sur la base des équilibres thermodynamiques des réactions de gazéification le rapport vapeur/comburant à injecter dans un gazogène fonctionnant sous pression pour optimaliser les compositions, les pouvoirs calorifiques, les rendements de gazéification et la consommation d'agent gazéifiant. The aim of this study is to determine, on the basis of the thermodynamic equilibria of gazification reactions, the steam/oxidizer ratio to be injected into a gas g...

  17. Can-rupture detection in gas-cooled nuclear reactors; La detection des ruptures de gaine dans les piles nucleaires refroidies par gaz

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    Can-rupture detection (DRG) is one important aspect of pile safety, more particularly so in the case of gas-cooled reactors. A rapid and sure detection constitutes also an improvement as far as the efficiency of electricity-producing nuclear power stations are concerned. Among the numerous can-rupture detection methods, that based on the measurement of the concentration of short-lived fission gases in the heat-carrying fluid has proved to be the most sensitive and the most rapid. A systematic study of detectors based on the electrostatic collection of the daughter products of fission gases has been undertaken with a view to equip the reactors EL 2, G 3, EDF 1, EDF 2 and EDF 3, the gas loops of PEGASE and EL 4. The different parameters are studied in detail in order to obtain a maximum sensitivity and to make it possible to construct detection devices having the maximum operational reliability and requiring the minimum maintenance. The primary applications of these devices are examined in the case of the above-mentioned reactors. (author) [French] La Detection des Ruptures de Gaines (D. R. G.) est un aspect important de la securite des piles et plus particulierement des piles refroidies par un gaz. Une detection rapide et sure constitue aussi un element d'amelioration du rendement des centrales nucleaires productrices d'energie electrique. Parmi les nombreuses methodes de detection des ruptures de gaines, la mesure de la concentration dans le fluide caloporteur des gaz de fission a vie courte s'est revelee comme la plus sensible et la plus rapide. Une etude systematique des detecteurs a collection electrostatique des descendants des gaz de fission a ete entreprise en vue d'equiper les piles EL 2, G 3, EDF 1, EDF 2 et EDF 3, les boucles a gaz de la pile Pegase et la pile EL 4. Les divers parametres sont etudies en detail pour obtenir une sensibilite maximum et permettre la realisation de dispositifs de detection ayant le maximum de securite de

  18. Dosage du mercure dans le gaz naturel par absorption atomique sans flammes Mercury Titration in Natural Gas by Flameless Atomic Absorption

    Directory of Open Access Journals (Sweden)

    La Villa F.

    2006-11-01

    Full Text Available Cet article présente la méthode mise au point par l'Institut Français du Pétrole pour déterminer par absorption atomique sans flamme, les traces de mercure métallique contenu dans un gaz naturel. La méthode d'analyse nécessite une extraction du mercure soit sous forme d'ion mercurique en faisant passer le gaz dans une solution oxydante, soit sous forme d'amalgame avec de l'or ou de l'argent. Le premier mode opératoire s'applique aux échantillons dont la concentration en mercure est supérieure à I ttg/Nm3, le second pour des concentrations inférieures à 5 pg/Nm3. Les seuils de détection sont respectivement 10 ng (en solution et 0,3 ng (en amalgame. La répétabilité pour 100 ng de mercure (en amalgame est de ± 7% pour une probabilité de.95 %. En conclusion, dans un échantillon de gaz naturel, compte tenu du volume des prélèvements effectués, il est possible de détecter des concentrations de l'ordre du nanogramme de mercure par mètre cube de gaz. This article describes the method developed by IFP using flameless atomic absorption to determine metallic mercury traces in a natural gas. The analyst method requires a mercury extraction either in the form of mercuric ions by making the gas pass through an oxidizing solution or in the form of an amalgam with gold or silver. The former operating method applies ta samples having a mercury concentration greater than I !ag/Nm3, and the latter for concentrations smaller than 5 (-Lg/Nm3. Detection thresholds are respectively 10 ng (in solution and 0.3 ng (in amalgam. The repeatability for 100 ng of mercury (in amalgam is ± 7 % with a probability of 95%. To conclude, in a sample of natural gas, considering the volume of the samples taken, it is possible ta detect concentrations in the vicinity of one nanogrom of mercury per cubic meter of gas.

  19. Irreversibility of Gas-Condensate Flow in Gas Cycling Projects: Kinetically Stable Saturation Patterns Irréversibilité des écoulements de gaz à condensat dans les projets de recyclage de gaz : profils stationnaires de saturation

    Directory of Open Access Journals (Sweden)

    Mitlin V.

    2006-12-01

    Full Text Available The dynamics of a two-phase multicomponent reservoir system which is approaching the steady-state flow regime are studied. First, the compositional model is analyzed in the linear approximation, for the case of a small initial deviation from the steady-state regime. An analytical expression is obtained for the characteristic relaxation time. Next, numerical simulations are performed for situations where there is a substantial deviation from the steady-state regime. The linear injection of an enriched gas into a gas-condensate reservoir, followed by the extraction regime, is simulated. It is shown that the change in phase compositions and pressure on the way to equilibrium proceeds with characteristic times of the order of the injection time. However, the change in the saturation and overall composition takes approximately 200 times longer than the injection time. Thus, the reservoir system manifests a spatially inhomogeneous saturation distribution for an abnormally long time. Similar kinetically stable patterns have been also discovered in the nonlinear dynamics of phase transitions, plasma, and thin films. The question of the existence of discontinuous steady states for this multicomponent flow is considered. In the case of a binary mixture, it is shown that such solutions do not exist. Cet article présente une étude de la dynamique d'un réservoir biphasique multiconstituant approchant le régime d'écoulement stationnaire. En premier lieu, nous procédons à une approximation linéaire du modèle compositionnel dans le cas des petites fluctuations autour du régime permanent. Une expression analytique est ainsi obtenue pour le temps caractéristique de transition. Des simulations numériques sont ensuite effectuées pour les déviations importantes par rapport au régime permanent. Nous avons ainsi pu étudier le déplacement linéaire d'un mélange gaz/condensat par un gaz enrichi suivi d'un régime de production. On montre alors que le

  20. Plasmas pour valorisation totale ou partielle des gaz contenant de l'H2S Plasmas for Total Or Partial Upgrading of H2s Containing Gases

    Directory of Open Access Journals (Sweden)

    Czernichowski A.

    2006-12-01

    Full Text Available Des procédés par plasmas alternatifs au procédé Claus sont proposés pour produire de l'hydrogène et récupérer du soufre à partir des gaz contenant une forte teneur en H2S. Quand la teneur en H2S est moins importante, des techniques plasma peuvent également être utiles pour assister certains étages du procédé classique Claus ou réaliser ce procédé pour des gaz non conventionnels. Les tests allant jusqu'à l'échelle industrielle sont menés dans divers réacteurs à plasmas et les résultats encourageants rapportés de la littérature et de la recherche propre laissent envisager des prochaines applications. Plasma assisted processes are proposed to act as an alternative to the Claus process in order to recover hydrogen and sulphur from high H2S gases. For less concentrated gases plasma techniques may also be inserted into classical Claus plant or may allow treatment of non conventional gases. Up to industrial scale tests are performed using different plasma reactors. The literature-based results as well as our own ones make the future applications quite optimistic.

  1. World Gas Prospects: Which Role for the Middle East? Perspectives mondiales du gaz naturel : quel rôle pourrait jouer le Moyen-Orient ?

    Directory of Open Access Journals (Sweden)

    Chabrelie M. F.

    2006-12-01

    Full Text Available Since the early 1970s, the policies of energy diversification that have been implemented in the industrialized countries and in many developing countries have enabled natural gas to regularly increase its role in the world energy balance. Thus, during the past twenty years, natural gas recorded the highest growth rate among fossil fuels, and its share in the energy market has gradually risen from 18. 9% in 1975 to 23% in 1997. Today, thanks to favorable economic and environmental factors, natural gas has become the fuel of choice on many markets. Indeed, gas is blessed with a certain number of favorable assets (abundant reserves, flexibility, high-performance uses which give it a major role in all energy demand forecast scenarios. The most spectacular development will indisputably take place in the power generation sector. Endowed with a considerable gas potential, the Middle East will represent an essential source of supply for many industrialized countries and several gas export projects, either by LNG tanker or by pipelines are currently being contemplated. During the past decade, the contribution of natural gas to the energy mix also grew substantially in most Middle Eastern countries. The increase in gas demand should continue at a sustained rate, mainly driven by the power generation sector, petrochemicals and energy consumption by the hydrocarbons industry. These promising prospects for gas demand in most of the markets in the region might lead to the development of an intra-regional network. However, although opportunities exist, the region will have to meet many challenges in order to contribute more largely to the world gas balance in the years to come. de diversification énergétique mises en Suvre dans les pays industrialisés et dans de nombreux pays en voie de développement depuis le début des années 1970 ont permis au gaz naturel d'accroître régulièrement sa présence dans le bilan énergétique mondial. Ainsi, au cours des

  2. Period Cramps

    Science.gov (United States)

    ... Too Tall or Too Short All About Puberty Period Cramps KidsHealth > For Kids > Period Cramps Print A ... re a girl who gets them. What Are Period Cramps? Lots of girls experience cramps before or ...

  3. 2001-2003 ''public utility'' contract between the French government and Gaz de France; Contrat de ''service public'' 2001-2003 entre l'etat et Gaz de France

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The ''public utility'' contract aims at specifying the actions of Gaz de France (GdF), the French gas utility, in terms of national development and public utility presence at the local scale. It extends and completes the 'contract of group' established between the government and GdF in the domain of quality of the services offered to clients, development of gas infrastructures and extension of gas supplies, and sustainable development. (J.S.)

  4. Ecoulements diphasiques gaz-liquide à poches et à bouchons en conduites Two-Phase Gas-Liquid Slug Flow in Pipes

    Directory of Open Access Journals (Sweden)

    Ferschneider G.

    2006-11-01

    Full Text Available Les écoulements diphasiques gaz-liquide ont été étudiés afin de contribuer à développer des modèles de calculs prédictifs des pertes de charge dans les conduites de production des bruts pétroliers. Les expériences nécessaires ont été réalisées sur la boucle diphasique de Boussens dans les conditions suivantes représentatives des conditions industrielles : diamètre 6 , longueur 120 m, disposition de la conduite horizontale ou faiblement ascendante, couple de fluide gaz naturel-huile légère. Le gradient de pression, le contenu global, et la distribution locale des phases ont été mesurés. Le traitement des équations de conservation phasique intégrées sur la section par différents types de moyennes a permis de développer un modèle cellulaire qui inclue un nombre limité d'équations constitutives nécessaires à sa fermeture. Ce modèle prédétermine convenablement le gradient de pression, le contenu gaz global et la longueur des poches et des bouchons. Two-phase gas-liquid flows were analyzed so as to develop models for prediction of pressure drops in crude-oil production lines. The experiments were performed on the two-phase loop at Boussens under the following representative industrial conditions: 6 diameter, 120 m length, horizontal or slightly rising pipe, couple of fluids natural gas and light oil. The pressure gradient, average content and local phase distribution were measured. Conservation phase equations integrated along the cross-section were processed by different time-averaged operators so as to develop a cellular model including a limited number of constitutive equations required for its closure. This model suitably predetermines the pressure gradient, the average gas content and the length of gas and liquid slug.

  5. Matériaux pour la dépollution des gaz d'échappement automobile

    Science.gov (United States)

    Mouaddib-Moral, N.; Gauthier, C.

    2002-04-01

    Les premières législations antipollution ont été mises en place suite à la détection, aux Etats Unis plus particulièrement en Californie, du smog photochimique et des pluies acides, néfastes pour la faune et la flore. Les estimations de la contribution de l'automobile aux émissions de composés, considérés comme précurseurs de ces phénomènes, ont été suffisantes pour provoquer la mise en place de normes draconiennes en matière d'émissions automobiles. Les matériaux catalytiques ont été évalués en tant que solution possible pour réduire les émissions à l'échappement. En Europe, l'utilisation des catalyseurs trois voies a été généralisée sur les véhicules essence fonctionnant à richesse stoechiométrique à partir de 1993. Une nouvelle génération de catalyseurs appelée piège à oxydes d'azote (NOx) est maintenant nécessaire pour le post-traitement des gaz d'échappement des motorisations à essence fonctionnant en mélange pauvre (combustion en présence d'un excès d'oxygène) pour diminuer la consommation et par conséquent réduire les émissions du CO2 connu pour son impact sur l'effet de serre. La dépollution des moteurs diesel via un catalyseur d'oxydation a été généralisée en Europe depuis 1996. La sévérisation des normes européennes impose pour les moteurs diesel le recours à des matériaux spécifiques pour le traitement des oxydes d'azotes et des particules par l'intermédiaire de filtres à particules dont l'efficacité de filtration est supérieure à 95%, mais doivent subir des régénérations périodiques.

  6. Arrimer le Nord au Sud pour réduire les émissions de gaz à effet de serre grâce au MDP

    Directory of Open Access Journals (Sweden)

    Moïse Tsayem Demaze

    2013-06-01

    Full Text Available Le Mécanisme pour un développement propre (MDP est le seul outil du Protocole de Kyoto qui associe les pays développés aux pays en développement afin de réduire les émissions de gaz à effet de serre. Les relations Nord-Sud qu’il crée sont illustrées dans cet article par les exemples du Royaume-Uni, des Pays-Bas, de la France et de la Belgique, qui prennent part à plus de la moitié des projets MDP. Ces exemples confirment la position dominante des pays émergents (Chine, Inde, Brésil qui, grâce à divers facteurs (économique, géographique, institutionnel, sont les principaux bénéficiaires de ce mécanisme.

  7. La formation de l'oxyde azotique dans les flammes de diffusion de gaz naturel Nitrogen. Oxyde Formation in Natural-Gas Diffusion Flams

    Directory of Open Access Journals (Sweden)

    Portrait L. M.

    2006-11-01

    Full Text Available L'étude de la formation de l'oxyde azotique dans des flammes de diffusion de ga naturel est effectuée depuis deux ans sur le four expérimental du Groupe d'Etude des Flammes de Gaz Naturel situé à Toulouse. Un certain nombre de variables ont été explorées : type de flamme, excès d'air, préchauffage de l'air, teneur en oxygène du comburant, puissance calorifique, et débit de moment cinétique. L'étude a mis en évidence une corrélation générale, quelle que soit la variable considérée, entre la quantité maximale d'oxyde d'azote formé et la température maximale de la flamme. Certains des résultats précédents ont été exploités à l'Institut Français du Pétrole, en vue d'établir une équation de vitesse de formation de NO applicable aux flammes axiales de diffusion de gaz naturel. Les calculs s'appuient sur les connaissances obtenues lors de l'étude cinétique de formation de NO effectuée au Laboratoire d'Aérothermique Fondamentale. Les résultats du calcul théorique confirment ceux de l'étude sur le four expérimental en ce qui concerne l'influence prépondérante de la température sur la formation de l'oxyde azotique. Par ailleurs, le calcul théorique retrouve bien les résultats obtenus lors de l'étude fondamentale, selon lesquels la cinétique de formation de NO évolue le long de la flamme depuis le front de flamme jusqu'aux gaz brûlés. La généralisation à un grand nombre de flammes de l'équation cinétique expérimentale obtenue nécessite maintenant de prendre en compte certains phénomènes de diffusion négligés jusqu'à présent. Research on the formation of nitrogen oxide in natural-gas diffusion flammes has been going on for two years in the experimental furnace of the Groupe d'Etude des Flammes de Gaz Naturel located in Toulouse. Different variables have been investigoted such as type of flamme, air excess, air preheating, oxygen content in the oxidant, heating power and kinetic moment output

  8. Ecoulement de gaz dans un long micro-canal : comparaison des modèles continu et cinétique

    OpenAIRE

    De Izarra, Léonard; Trouette, Benoît; Rouet, Jean-Louis; Izrar, Boujema

    2013-01-01

    National audience; Les écoulements de gaz dans des micro ou nano conduites mettent en jeu des effets de raréfaction et de compressibilité. Différents régimes d'écoulement (hydrodynamique, de glissement ou transitionnel) sont alors susceptibles de cohabiter et il est nécessaire d'utiliser une approche et des méthodes numériques adaptées. Les solutions obtenues par une méthode de résolution de l'équation de Boltzmann-BGK sont comparées aux solutions des équations de Navier-Stokes compressibles ...

  9. Olgunlaşma Döneminin Kinoa (Chenopodium quinoa Willd.)’da Ot Verimi ve Kalitesi ile Gaz ve Metan Üretimine Etkisi

    OpenAIRE

    KAPLAN, Mahmut; ÜKE, Özlem; KALE, Hasan; KAMALAK, Adem

    2016-01-01

    Çalışmanın amacı farklı olgunlaşma dönemlerinde (çiçeklenme öncesi, tam çiçeklenme ve tohum bağlama) hasat edilen kinoa bitkisinin (Chenopodium quinoa Willd.) yeşil ve kuru ot verimi, besleme değeri, in vitro gaz ve metan üretimi, metabolik enerji (ME) ve organik madde sindirim derecesine (OMS) etkisini belirlemektir. Kinoa bitkisinin olgunlaşması araştırmada incelenen tüm parametreleri etkilemiştir (P≤0.01). Çalışma sonuçlarına göre olgunlaşma döneminin ilerlemesiyle yeşil ve kuru ot verimle...

  10. Modélisation et simulation de la boucle des gaz dans un moteur diesel suralimenté à injection directe

    OpenAIRE

    Sabeh, Zahi; Ragot, José; Maquin, Didier

    2008-01-01

    National audience; La complexité des moteurs diesel modernes contrôlés par l'électronique, avec un nombre croissant de capteurs et d'actionneurs, nécessite des systèmes de mesure et de diagnostic améliorés et automatisés à bord des véhicules utilisant ces moteurs. La surveillance appropriée et la détection précoce des défauts nécessite de disposer de modèles de bon fonctionnement des composants et, dans cette communication, on s'intéresse à la boucle des gaz d'un moteur diesel à injection dir...

  11. Guidebook of natural gas air conditioning in the buildings of territorial organizations; Guide de la climatisation gaz naturel dans les batiments des collectives territotiales

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-06-01

    In the framework of the 'common energy' approach, a partnership between Gaz de France (GdF) and the territorial associations (association of French territorial engineers (AITF) and association of French territorial graduate technicians (ATTF)), the publication since 15 years of this book of good practices makes a status of the implementation of natural gas air-conditioning in the buildings of the territorial organizations. Its aim is to supply information about the absorption principle, the existing products, the design of a natural gas air-conditioning system, its implementation, exploitation and maintenance. It presents also some experience feedbacks (town halls, swimming pools..) and three reference files in appendix. (J.S.)

  12. Microgénérateurs à aimants permanents entraînés par des microturbines à air ou des micromachines à gaz chaud

    OpenAIRE

    Herrault, Florian

    2009-01-01

    L'énergie nécessaire au fonctionnement des systèmes électroniques est en train de surpasser les capacités des batteries actuelles. Par conséquent, l'application des technologies MEMS pour la conception de nouvelles sources de puissance à haute performance est très attractive. Cette thèse considère la fabrication de microgénérateurs entraînés par gaz froid ou chaud. Tout d'abord, nous avons développé des microgénérateurs à aimants permanents compatibles avec le fonctionnement de micromachin...

  13. Transport diphasique de gaz et de condensat. Aspects techniques et économiques Technical and Economic Aspects of Two-Phase Pipelining of Gas and Condensate

    Directory of Open Access Journals (Sweden)

    Bourgeois T.

    2006-11-01

    Full Text Available L'évacuation diphasique de la production d'un gisement de gaz à condensat présente des avantages importants, en particulier sur le plan économique. Les caractéristiques des écoulements diphasiques sont exposées, avec les conséquences principales sur la définition d'un schéma d'exploitation. Une comparaison économique est ensuite présentée, pour illustrer la réduction des investissements qui peut être apportée par l'évacuation diphasique de la production. Enfin, les recherches françaises sur les écoulements diphasiques dans les conduites pétrolières sont brièvement décrites, ainsi qu'un exemple de calcul sur une conduite de gaz à condensat en exploitation diphasique. The two-phase pipelining of a wet gas field production presents many advantages, especially from an economic point of view. The characteristics of two-phase flow are described, together with their main consequences on the operational scheme. Then an economic comparison is made to illustrate the reduction in investment costs that can by achieved with two-phase pipelining. Research in France on two-phase flow in gas and condensate pipelines is briefly described, and an example is given of the designing of a wet-gas pipeline currently being operated in the two-phase mode.

  14. Strategy of adaptation to competition of a local public utility company in a situation of monopoly: the case of Gaz de Strasbourg SA; Strategie d'adaptation a la concurrence d'une societe locale de service public en monopole: le cas de Gaz de Strasbourg SA

    Energy Technology Data Exchange (ETDEWEB)

    Carbonnier, R.

    2001-07-01

    This work deals with the creation process and the definition of the strategy content of Gaz de Strasbourg company at a time when this local monopoly company has to face the deregulation of the gas market and the competition. Its aim is to give help to the company in the identification of the stakes and to adopt and implement the proper strategies in a context dominated by the 'essential facility doctrine' which makes a distinction between the activities linked with the physical network infrastructures, considered as 'natural monopoly', and the commercialization activities of the natural gas product. The strategy proposals are built with the prospect of splitting of the company into two or three different layers of activities and using the concepts and tools of structural analysis, inspired from Michael Porter, and the resources and competences model. It includes an analysis of the activities of a natural gas network company, like Gaz de Strasbourg, and of their evolution in an integrated or in a disintegrated structure. (J.S.)

  15. Gasification in Petroleum Refinery of 21st Century La gazéification dans la raffinerie du pétrole du XXIe siècle

    Directory of Open Access Journals (Sweden)

    Furimsky E.

    2006-12-01

    goudrons, le coke et l'asphalte, résultant respectivement de la viscoréduction, de la carbonisation et du désasphaltage. Les résidus finaux peuvent être, à leur tour, convertis en produits utilisables comme l'hydrogène, la vapeur, l'électricité, l'ammoniac et des produits chimiques. Dans ce contexte, la gazéification est apparue comme la technologie de choix pour la valorisation des résidus en raison de ses meilleures performances. De même, les boues de raffinerie peuvent être cogazéifiées avec les résidus finaux et devenir alors des produits valorisables. Intégrée à la raffinerie de pétrole, la gazéification peut aider à résoudre les problèmes environnementaux liés à l'élimination des résidus et des boues. Les résultats économiques de la raffinerie peuvent également être améliorés. Les tendances de déréglementation du marché de l'énergie permettent aux raffineries de pétrole d'y pénétrer, soit toutes seules, soit en partenariat avec les fournisseurs d'utilités. Le potentiel de coproduction de produits chimiques et de vapeur avec l'électricité offre une souplesse de réaction permettant de répondre aux demandes du marché. L'intérêt de la technologie de la gazéification est commercialement démontré. Parmi d'autres, les gazéificateurs à lit entraîné sont les gazéificateurs de prédilection. Plusieurs projets commerciaux en Europe, en Asie et aux États-Unis font appel à un gazéificateur utilisant soit un système d'alimentation en suspension, soit un système d'alimentation par voie sèche.

  16. Periodic paralysis.

    Science.gov (United States)

    Fontaine, Bertrand

    2008-01-01

    Periodic paralyses are rare diseases characterized by severe episodes of muscle weakness concomitant to variations in blood potassium levels. It is thus usual to differentiate hypokalemic, normokalemic, and hyperkalemic periodic paralysis. Except for thyrotoxic hypokalemic periodic paralysis and periodic paralyses secondary to permanent changes of blood potassium levels, all of these diseases are of genetic origin, transmitted with an autosomal-dominant mode of inheritance. Periodic paralyses are channelopathies, that is, diseases caused by mutations in genes encoding ion channels. The culprit genes encode for potassium, calcium, and sodium channels. Mutations of the potassium and calcium channel genes cause periodic paralysis of the same type (Andersen-Tawil syndrome or hypokalemic periodic paralysis). In contrast, distinct mutations in the muscle sodium channel gene are responsible for all different types of periodic paralyses (hyper-, normo-, and hypokalemic). The physiological consequences of the mutations have been studied by patch-clamp techniques and electromyography (EMG). Globally speaking, ion channel mutations modify the cycle of muscle membrane excitability which results in a loss of function (paralysis). Clinical physiological studies using EMG have shown a good correlation between symptoms and EMG parameters, enabling the description of patterns that greatly enhance molecular diagnosis accuracy. The understanding of the genetics and pathophysiology of periodic paralysis has contributed to refine and rationalize therapeutic intervention and will be without doubts the basis of further advances.

  17. Gas and electric power opening of the markets. Reality, limits and paradoxes the position of the cogeneration; Gaz electricite ouverture des marches. Realite, limites et paradoxes place de la cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    During these two days of the colloquium on gas and electric power market opening, industrial and french administration discussed about the new market deregulation impacts and the cogeneration position in this context. The position of EDF and Gaz De France, the european competition and the government policy are presented. These nineteen papers proposed an economic analysis and the state of the art of the situation. (A.L.B.)

  18. Detection of radioactive gases in the CO{sub 2} cooling the reactors G 2 - G 3; Detection des gaz radioactifs dans le CO{sub 2} de refroidissement des piles G2 - G3

    Energy Technology Data Exchange (ETDEWEB)

    Pouthier, J.; Rossi, J. [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

    1968-07-01

    The carbon dioxide cooling the reactors G2 - G3 contains activation gases and fission gases. It is of interest to know their concentration, for example to be able to deduce rapidly the norms which would have to be applied in the case of an incident in the circuit. Gas-phase chromatography is applied daily for carrying out analyses. The chromatogram has separate peaks due to tritium, argon 41, krypton 85 and the 133 and 135 isotopes of xenon. By integrating each peak it is possible to calculate the specific activity of each product. The construction of an apparatus for carrying out continuous measurements is under consideration. (authors) [French] Le gaz carbonique, refroidissant les reacteurs G2 - G3, contient des gaz d'activation et des gaz de fission. Il est interessant de connaitre leur teneur par exemple pour etre en mesure de deduire rapidement les normes qu'il y aurait lieu d'appliquer en cas d'incidents sur le circuit. La methode de chromatographie en phase gazeuse est employee quotidiennement pour faire des analyses. Le chromatogramme se presente sous forme de pics distincts dus au tritium, a l'argon 41, au krypton 85 et aux isotopes 133 et 135 du xenon. L'integration de chaque pic permet de calculer l'activite specifique de chaque compose. Il est envisage de construire un appareil pour des mesures en continu. (auteurs)

  19. Depo Gazı Enerji Üretim Tesisi Baca Gazı Atık Isısının Seralarda Değerlendirilmesi: İstanbul Örneği / Utilization of Waste Heat in Energy Production Plant from Landfill Gas at Greenhouses – Case Study in Istanbul

    Directory of Open Access Journals (Sweden)

    Volkan Enç

    2012-12-01

    Full Text Available Evsel atık düzenli depolama sahaları kullanım ömrü dolduktan sonra yararlı kullanım alanları sınırlı sahalardır. Çoğunlukla yeşil alan olarak kullanılan bu yerler ekonomik ve çevresel anlamda atıl durumda bulunmaktadır. Depolama sahalarının İstanbul gibi arazi sıkıntısı çeken bir şehirde yararlı amaçlar için kullanılması elzemdir. Depolama sonrası sahalarda metan gazı oluşmakta ve farklı yöntemlerle kontrol altına alınmaktadır. Bu gazların toplanması, taşınması ve özel motorlarda yakılması ile elektrik enerjisi üretilmektedir. Tesislerde gazın yakılması, depo gazı içerisinde bulunan CH4 (metan gazının CO2’e indirgenmesini sağlayarak sera etkisini azaltmakta, elektrik enerjisi üreterek ekonomiye katkı sağlamaktadır. Çevresel ve ekonomik yarar göz önüne alındığında, depo gazından enerji üretim tesislerinde, enerji üretiminde mümkün olabilecek maksimum verime ulaşılmalıdır. Bu düşünce ile bakıldığında, depo gazı enerji üretim tesisinde oluşan atık ısının değerlendirilemeden atmosfere verilmesi önemli bir sorun olarak ortaya çıkmaktadır. Oldukça yüksek debi ve sıcaklığa sahip bu ısı, enerji bakımından önemli bir potansiyele sahiptir. Bu sıcaklıktaki ve debideki ısının değerlendirilmeden atmosfere verilmesi, çevreyi olumsuz etkilemesinin yanında ekonomik kayıplara yol açmaktadır. Seralarda mevsimlik çiçek üretimi, maliyeti yüksek bir faaliyettir. Maliyetlerin önemli bir kısmını sera ısıtılması ve gübre kullanımı oluşturmaktadır. Isıtma işlemi için Türkiye’nin büyük bir bölümünde kömür ve doğalgaz kullanılmaktadır. Kışın seraların ısıtılması için kullanılan fosil yakıtların hem maliyeti yüksek, hem de çevresel standardı düşüktür. Bu çalışma, İstanbul Kalkınma Ajansı (İSTKA tarafından desteklenen “Depo Gazı Enerji Üretim Tesisi Atık Isının ve Kompostun Seralarda

  20. Irregular Periods

    Science.gov (United States)

    ... blood become too low or too high. Some women have irregular periods because their bodies produce too much androgen, which is a hormone that causes increased muscle mass, facial hair, and deepening of the voice in males and ...

  1. Period Pain

    Science.gov (United States)

    ... You may also have other symptoms, such as lower back pain, nausea, diarrhea, and headaches. Period pain is not ... Taking a hot bath Doing relaxation techniques, including yoga and meditation You might also try taking over- ...

  2. Gaz - almaz / Jekaterina Rodina

    Index Scriptorium Estoniae

    Rodina, Jekaterina

    2008-01-01

    Venemaa Energiapoliitika Instituudi arvutuste kohaselt võib maagaasi tootmise ja nõudluse vahe ulatuda 2010. aastaks 100 miljardi kuupmeetrini, Kui maagaasi tarned Eestisse ära jäävad, saab meie riik omal jõul hakkama kõige rohkem kuu aega. Vt. samas: Gaas arvudes

  3. Gas mission; Mission gaz

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

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

  4. Gaz - almaz / Jekaterina Rodina

    Index Scriptorium Estoniae

    Rodina, Jekaterina

    2008-01-01

    Venemaa Energiapoliitika Instituudi arvutuste kohaselt võib maagaasi tootmise ja nõudluse vahe ulatuda 2010. aastaks 100 miljardi kuupmeetrini, Kui maagaasi tarned Eestisse ära jäävad, saab meie riik omal jõul hakkama kõige rohkem kuu aega. Vt. samas: Gaas arvudes

  5. Application of Continuous Thermodynamics to Natural-Gas Mixtures Application de la thermodynamique continue aux mélanges de gaz naturel

    Directory of Open Access Journals (Sweden)

    Prausnitz J. M.

    2006-11-01

    Full Text Available This work reviews recent progress in the application of continuous thermodynamics towards calculation of phase equilibria in natural-gas mixtures. In such mixtures, there may be too many components to identify each component individually. Continuous thermodynamics provides a theoretical framework for representing the composition of a portion of the natural-gas mixture by a continuous distribution function. Advances in continuous thermodynamics are discussed in three areas :(1 Characterization and representation of composition in a many-component mixture(2 Development and application of molecular-thermodynamic models for continuous mixtures, and(3 Implementation of efficient numerical techniques for solving material-balance and phase-equilibrium equations. While continuous thermodynamics provides a useful tool for calculation of phase equilibria in natural-gas mixtures, successful implementation requires better chemical-analytical characterization methods. Further, improved semi-theoretical techniques must be developed to relate experimental characterization information to physically significant parameters in molecular-thermodynamic models. Ce travail examine les récents développements de l'application de la thermodynamique continue au calcul des équilibres de phases de mélanges de gaz naturel. Dans ces mélanges, les composants sont souvent en trop grand nombre pour qu'on puisse les identifier individuellement. La thermodynamique continue fournit un schéma théorique permettant de représenter la composition d'une partie de mélange de gaz naturel par une fonction de distribution continue. Les progrès de la thermodynamique continue sont examinés dans les trois domaines suivants : 1 caractérisation et représentation de la composition d'un mélange de plusieurs produits; 2 mise au point et application des modèles de thermodynamique moléculaire aux mélanges continus; 3 mise en oeuvre de techniques numériques efficaces pour r

  6. Gazâlî ve Thomas Aquinas’ta Tanrı’nın Kudreti ve İmkânsızlık

    Directory of Open Access Journals (Sweden)

    Özcan Akdağ

    2016-06-01

    Full Text Available Ortaçağ’da, İslam düşüncesi içerisinde yazılmış olan İbn Sînâ’nın eş-Şifâ: İlahiyat’ı, Gazâlî’nin Makâsıdu’l-Felâsife’si ve İbn Rüşd’ün, Aristoteles’in eserlerine yazmış olduğu şerhler gibi pek çok felsefî ve teolojik eser Latinceye çevrilmiştir. Söz konusu çeviri eserler vasıtasıyla, İslam düşüncesinde carî olan, Tanrı’nın tikelleri kendi zatlarında bilip bilmediği, Tanrı’nın zatı gereği fiilde bulunup bulunmadığı, din ve felsefenin uzlaşıp uzlaşmayacağı gibi tartışmalı pek çok mesele Batı’ya intikal etmiştir. Bunlara ilaveten Tanrı’nın mutlak kudretinin alanının ne olduğu sorunu da Batı düşüncesinde bilinir hale gelmiştir. Bu çalışmada, “Tanrı mantıksal olarak mümkün olanı yapabilir ve bu durum Tanrı’nın mutlak kudretine halel getirmez” anlayışının Latin Batı dünyasına İbn Sînâ’nın eş-Şifâ’sı ve Gazâlî’nin Makâsıd’ının çevrileri vasıtasıyla intikal ettiği ortaya konulmaya çalışılmıştır. Tespit edebildiğimiz kadarıyla, Gazâlî’nin Makâsıd’ta bu konuya ilişkin serdettiği fikirler ile Hıristiyan teolog/düşünür Thomas Aquinas’ın fikirleri arasında önemli ölçüde benzerlik söz konusudur. Söz konusu benzerlik temele alınarak, Thomas Aquinas’ın bu hususta İslam düşüncesinden beslendiği düşüncesinin kuvvetle muhtemel olduğu söylenebilir.

  7. Periodic behaviors

    CERN Document Server

    Napp, Diego; Shankar, Shiva

    2010-01-01

    This paper studies behaviors that are defined on a torus, or equivalently, behaviors defined in spaces of periodic functions, and establishes their basic properties analogous to classical results of Malgrange, Palamodov, Oberst et al. for behaviors on R^n. These properties - in particular the Nullstellensatz describing the Willems closure - are closely related to integral and rational points on affine algebraic varieties.

  8. PERIODIC BEHAVIORS

    NARCIS (Netherlands)

    Napp, Diego; Put, Marius van der; Shankar, Shiva

    2010-01-01

    This paper studies behaviors that are defined on a torus, or equivalently, behaviors defined in spaces of periodic functions, and establishes their basic properties analogous to classical results of Malgrange, Palamodov, Oberst et al. for behaviors on R(n). These properties-in particular the Nullste

  9. Étude des équilibres thermodynamiques des réactions de gazéification en vue de l'optimisation du rapport vapeur/comburant injecté dans un gazogène souterrain Study of Thermodynamic Equilibria in Gasification Reactions So As to Optimise the Steam/Oxidizer Ratio Injected Into an Underground Gas Generator

    Directory of Open Access Journals (Sweden)

    Pirard J. P.

    2006-11-01

    Full Text Available Le but de cette étude est de déterminer sur la base des équilibres thermodynamiques des réactions de gazéification le rapport vapeur/comburant à injecter dans un gazogène fonctionnant sous pression pour optimaliser les compositions, les pouvoirs calorifiques, les rendements de gazéification et la consommation d'agent gazéifiant. The aim of this study is to determine, on the basis of the thermodynamic equilibria of gazification reactions, the steam/oxidizer ratio to be injected into a gas generator operating under pressure so as to optimize the compositions, the heating values, the gasification efficiencies and the consumption of gasifying agent.

  10. CO{sub 2} direct cycles suitable for AGR type reactors; Cycles directs de gaz carbonique applicables aux reacteurs du genre AGR

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-10-01

    The perspectives given by the gas turbines under pressure, to build simple nuclear power plants and acieving significantly high yield, are specified. The CO{sub 2} is characterised by by good efficiency under moderate temperature (500 to 750 Celsius degrees), compactness and the simpleness of machines and the safe exploitation (supply, storage, relief cooling, thermosyphon). The revision of thermal properties of the CO{sub 2} and loss elements show that several direct cycles would fit in particular to the AGR type reactors. Cycles that would diverge a little from classical models and able to lead to power and heat generation can lead by simple means to the best results. Several satisfying solutions present for the starting up, the power regulation and the stopping. The nuclear power plant components and the functioning safety are equally considered in the present report. The conclusions stimulate the studies and realizations of carbon dioxide gas turbines in when approprite. [French] Les perspectives offertes par la turbine a gaz sous pression, pour construire des centrales nucleaires simples et de rendement progressivement eleve, se precisent actuellement. le CO{sub 2} se distingue par sa bonne efficacite a temperature moderee (500 a 750 degres celsius), la compacite et la simplicite des machines, et la surete qu'il apporte a l'exploitation ( approvisionnement, stockage, refroidissement de secours, thermosiphon). La revision des proprietes thermophysiques du CO{sub 2} et des elements de pertes montre que divers cycles directs conviendraient en particulier aux reacteurs agr ou derives. Des cycles s'ecartant peu des modeles classiques, et se pretant ulterieurement a la production simultanee d'electricite et de chaleur, peuvent conduire par des moyens simples aux meilleurs resultats d'ensemble. Plusieurs solutions satisfaisantes se presentent pour le demarrage, le reglage de la puissance et l'arret. Les composants de la centrale et la

  11. PAMUK YAĞI-GAZ YAĞI KARIŞIMI KULLANILAN BİR DİZEL MOTORUNUN PERFORMANS DEĞERLENDİRMESİ

    OpenAIRE

    2007-01-01

    Bu çalışmada, pamuk yağı değişik oranlarda gaz yağına katılarak hazırlanan yakıt karışımı(COK), 4 zamanlı, tek silindirli hava soğutmalı bir dizel motorunda test edilmiştir. Değişik oranlarda hazırlanan karışımlar kullanılarak motor gücü, motor momenti, özgül yakıt tüketimi ve özgül enerji tüketimi parametreleri tespit edilmiş ve dizel yakıtı ile karşılaştırılmıştır. Deneysel sonuçlar motor gücü, motor momenti ve özgül yakıt tüketimi gibi parametrelerin dizel yakıtına göre çok az farklı olduğ...

  12. Epidemiological Surveillance at Electricite de France and Gaz de France: Health Assessment of Nuclear Power Plant Employers between 1993 and 1998

    Energy Technology Data Exchange (ETDEWEB)

    Chevalier, A.; Gros, H.; Carrier, E.; Labon, G.

    2004-07-01

    Because the 17,500 employees working in nuclear power plants at Electricite de France, the national power company, may be exposed to a wide variety of industrial hazards, the health insurance department of the company has set up an epidemiologic surveillance programme for them. This descriptive, cross-sectional,and exhaustive study examined sick-leaves, mortality and cancer incidence to assess the health of the employees working from 1993 through 1998. The analysis comparing the employees in nuclear power plants, considered exposed, to the rest of the personnel of Electricite de France-Gaz de France, the non-exposed (125,000 persons) showed that globally, the employees in the nuclear sector appeared to have fewer health problems than the other company employees. This was true regardless of age and especially for men, operating employees, and supervisory employees. Nonetheless three points must be noted: non-work accidents generated a non-significant excess of absenteeism and mortality among these employees, especially among management and supervisory personnel; suicides affected supervisors in particular; and an excess of primary malignant brain tumors affected both mortality (RR{sub 1}.96, NS) and incidence, especially among operating employees (RR=2.87, 95% CL=(1.00-8.43)). No excess of malignant blood disease was observed. (Author) 38 refs.

  13. La gazéification souterraine profonde du charbon en France. L'expérience de Bruay-en-Artois Underground Coal Gasification At Great Depth. The French Field Test of Bruay-En-Artois

    Directory of Open Access Journals (Sweden)

    Gadelle C.

    2006-11-01

    Full Text Available Le projet français de gazéification souterraine du charbon, dont l'objectif à terme est la production d'un substitut de gaz naturel, vise la gazéification de veines de charbon de faible épaisseur, situées à grande profondeur et non exploitables par les méthodes classiques. De nombreuses difficultés sont liées à la profondeur (plus de 1000 m, en particulier la nécessité d'opérer sous pression élevée dans un charbon très peu perméable. Les premiers essais, effectués sur un pilote à 1200 m de la surface sur le site de Bruay-en-Artois (nord de la France, ont consisté à :- relier deux puits distants de 65 m par fracturation hydraulique, un test de la liaison par injection d'azote indiquant un taux de récupération du gaz injecté proche de 50 % ; - allumer le charbon au moyen d'un allumeur électrique ; - initier et tenter de propager une combustion à contre-courant avec injection d'air à faible débit. Des expériences de laboratoire, consécutives à cet essai pilote, ont mis en évidence les risques d'allumage spontané du charbon lorsque la pression partielle d'oxygène dans le gaz injecté est élevée. Un nouvel essai de combustion à contre-courant a alors été entrepris sur le site de Bruay-en-Artois, avec injection d'un gaz contenant 5 % d'oxygène et 95 % d'azote. Les résultats de cette expérimentation arrêtée en juillet 1981 sont en cours d'exploitation. The French underground coal gasification (UCG project, which has the objective of producing synthetic natural gas, aims to gasify deep thin coal seams that cannot be mined by conventional methods. Many difficulties are connected with depth (more than 1000 m, in particular the necessity to operate under high pressure in low permeable coal. The initial pilot tests performed at a depth of 1200 m from the surface at Bruay-en-Artois (northern France consisted in: (a linking two boreholes 65 m apart by hydraulic fracturing, a linkage test by nitrogen injection

  14. Risk Analysis of Flare Flame-out Condition in a Gas Process Facility Analyse des risques des conditions d’extinction de torche au sein d’une installation de traitement de gaz

    Directory of Open Access Journals (Sweden)

    Zadakbar O.

    2011-02-01

    Full Text Available Flaring is a common method of disposal of flammable waste gases in the downstream industries. Flare flame out (flame lift-off or blow-outs often occurs causing toxic vapors to discharge. The toxic gases released may have hazardous effects on the surrounding environment. To study the effect of inhalation exposure of these toxic gases on human health, the four steps of the EPA (Environmental Protection Agency framework with the field data to quantify the cancer and non-cancer health risks are integrated in this paper. As a part of exposure assessment, gas dispersion modeling using AERMOD and UDM-PHAST is applied in two different conditions of normal flaring and flare flame out during a particular climate condition in Khangiran region. Recommendations to avoid flare flame out conditions are also presented here. Le torchage est un procédé courant d’élimination des gaz résiduaires inflammables dans les industries de traitement. L’extinction de la torche (par décollage ou soufflage de flamme provoque souvent une émission de vapeurs toxiques. Ces gaz toxiques libérés peuvent présenter des effets dangereux sur le milieu environnant. Pour étudier l’effet d’une exposition par inhalation de ces gaz toxiques sur la santé, cet article croise les quatre étapes de la démarche de l’EPA (Environmental Protection Agency, Agence de protection de l’environnement avec les données d’exploitation afin de quantifier le risque sanitaire cancérologique et non cancérologique. Dans le cadre de l’estimation d’exposition, une modélisation de dispersion des gaz utilisant AERMOD et UDM-PHAST est évaluée dans deux configurations différentes de torchage normal et d’extinction de torche à l’occasion de conditions climatiques particulières dans la région du Khangiran. L’article propose également des recommandations destinées à éviter les conditions d’une extinction de flamme de torche.

  15. Libéralisation du marché de l'énergie, réorganisation du travail et mobilisation collective dans l'entreprise. Le cas de Gaz de Bordeaux

    OpenAIRE

    Dif-Pradalier, Maël

    2011-01-01

    Thèse réalisée dans le cadre d'une convention CIFRE (convention industrielle de formation par la recherche); Formerly in a monopolistic situation and running on a politico-administrative mode, Gaz de Bordeaux is a network industry now part of a competitive market. The present case study of this local public utility is meant to identify the nature of its modernisation and to measure its effects as well on the system of social regulations and professional identities, as on the capacities of act...

  16. Economical and geopolitical aspects bond to the foreseen development of the natural gas in an open market; Aspects economiques et geopolitiques lies au developpement prevu du gaz naturel dans un marche ouvert

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-15

    For the first time in 2000, the part of natural gas is equal to those of coal in the world energy accounting. The economy and the geo-policy of this developing energy is analyzed, showing an economy dominated by the transport costs, the specificity of the european sector and the opening market since 1980. The european market opening incertitudes and opportunities are detailed. In conclusion the Gaz De France role in the european energy pole and the new regulations are discussed. (A.L.B.)

  17. Possibilités de contribution de la gazéification Lurgi à notre approvisionnement énergétique futur Potential Contribution of Lurgi Gasification to Our Future Energy Supplies

    Directory of Open Access Journals (Sweden)

    Eckert G.

    2006-11-01

    Full Text Available Pour la valorisation du charbon, la gazéification est une possibilité immédiatement utilisable et industriellement éprouvée, qui présente l'avantage de permettre la production des formes d'énergie secondaire, auxquelles nous sommes habitués. Indépendamment du produit final, une unité de conversion du charbon est toujours constituée d'étapes de transformation successives, mettant en oeuvre des procédés adaptés, parmi lesquels la gazéification de charbon proprement dite constitue la première étape qui n'est cependant qu'une opération parmi d'autres. Le traitement des gaz et la séparation des produits secondaires sont mis en oeuvre également et sont importants dans l'ensemble du complexe de traitement. Dans la communication présentée, trois possibilités différentes sont évoquées : - production de gaz de chauffage de différents pouvoirs calorifiques ; - production de méthanol et transformation éventuelle de celui-ci en essence ; - production d'hydrocarbures par la synthèse de Fischer-Tropsch. Une approche économique générale dégage une idée d'ensemble sur la situation et l'intérêt des techniques de conversion du charbon à l'heure actuelle. For the upgrading of coal, gasification is an immediately available and industrially well-proven possibility which has the advantage of making it possible to produce the types of secondary energy to which we have become accustomed. Independently of the end product, a coal conversion plant always consists of successive transformation steps making use of suitable processes, among which coal gasification itself is the first such step, although being only one operation among others. Gas processing and secondary products separation are also implemented and are important in the overall processing complex. This article brings out three different possibilities: (a production of fuel gas with different heating values; (b production of methanol and eventual transformation into gasoline

  18. Descriptif et qualification d'un mode opératoire de soudage pour les matériaux métalliques - Épreuve de qualification d'un mode opératoire de soudage - Partie 6: Soudage à l'arc et aux gaz du cuivre et de ses alliages

    CERN Document Server

    2006-01-01

    Descriptif et qualification d'un mode opératoire de soudage pour les matériaux métalliques - Épreuve de qualification d'un mode opératoire de soudage - Partie 6: Soudage à l'arc et aux gaz du cuivre et de ses alliages

  19. Hydrodynamique, transfert de chaleur et combustion de gaz naturel en lit fluidisé circulant Hydrodynamics, Heat Transfer and Combustion of Natural Gas in a Circulating Fluidized Bed

    Directory of Open Access Journals (Sweden)

    Feugier A.

    2006-11-01

    Full Text Available L'hydrodynamique, les transferts de chaleur et la combustion du gaz naturel ont été étudiés dans un réacteur à lit circulant de 15 cm de diamètre et de 7 m de haut. Ce réacteur peut opérer avec des vitesses de gaz allant jusqu'à 15 m/s, jusqu'à des températures de 880-900°C et avec des débits de solides compris entre 0 et 15t/h. Les charges utilisées sont des sables de granulométrie allant de 95 à 625 microns. Le profil de concentration en solides dans le réacteur est déterminé à partir du profil de pression. Une corrélation reliant la vitesse de glissement des particules aux principaux paramètres opératoires, rend compte de façon très satisfaisante de l'ensemble des résultats expérimentaux. La mise en place d'un échangeur en paroi dans la partie supérieure du réacteur a permis la détermination de coefficients d'échange thermique. Ces derniers sont essentiellement fonction de la, concentration en particules au droit de l'échangeur et de la granulométrie des particules. Des valeurs allant jusqu'à 200 W/m2 K peuvent, être obtenues. Enfin, la combustion du méthane s'avère très sensible à la présence de particules dans le réacteur. Ces particules ont un effet inhibiteur. Hydrodynamics, heat transfer and combustion of natural gas have been investigated in a circulating-bed reactor 15 cm in diameter and 7 m high. This reactor can operate with gas velocities up to 15 m/s, at temperature up to 880-900°C and with solids flow rates of between 0 and 15 t/h. The solids used are sands with a particle size ranging from 95 to 625 microns. The solids concentration profile in the reactor is determined from the pressure profile. A correlation linking the slippage velocity of particles to the principal operating parameters very satisfactorily takes into consideration the overall experimental results. The installation of a wall heat exchanger in the upper part of the reactor enabled the heat exchange coefficients to be

  20. Enjeux juridiques du contrôle des émissions personnelles de gaz à effet de serre par un dispositif de carte carbone

    Directory of Open Access Journals (Sweden)

    Sandrine Rousseaux

    2011-02-01

    Full Text Available La carte carbone individuelle est un dispositif innovant, qui permet d’impliquer les particuliers dans la lutte face au changement climatique. Ce dispositif consiste à limiter leurs émissions de gaz à effet de serre, ce qui suppose de suivre leur consommation de certains produits et services. Ce mode de contrôle des émissions personnelles soulève parfois des controverses, la carte carbone pouvant être perçue comme un instrument de rationnement potentiellement liberticide. Ces deux aspects sont discutés sur la base d’une analyse comparative de la conception et des modalités de mise en œuvre des différents dispositifs de carte carbone, établis ou envisagés en Europe et aux États-Unis. Il en ressort que les controverses ne sont pas réellement fondées.The individual carbon card is an innovative mechanism that helps involve individuals in the fight against climate change. It consists in limiting their greenhouse gas emissions, which requires monitoring a part of their goods and services consumption. This method of personal emissions control is much debated since the carbon card may be perceived as a rationing tool and raises civil liberty issues. Both of these controversial aspects are discussed on the basis of a comparative analysis of how the various carbon card programs, established or contemplated in Europe and in the USA, are designed and implemented. The findings are these controversies are somewhat groundless.

  1. A study on the isotope effects in the reduction of carbon dioxide by zinc; Etude des effets isotopiques dans la reduction du gaz carbonique par le zinc

    Energy Technology Data Exchange (ETDEWEB)

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

    1957-06-15

    We have determined the isotope effects which occur in the reduction of carbon dioxide by zinc. It has been shown that in the case of irreversible surface reactions, Bernstein's equation which permits the calculation of the fractionation factor is still valid. These experimental factors are in good agreement with those obtained by calculating the partition functions of the adsorbed activated complexes. In the reaction mechanism used, the model of the activated complex corresponds to the dissociation of one of the carbon oxygen bonds CO{sub 2} {yields} CO + O. Perturbations arising from the slight reversibility of the reaction Zn + CO{sub 2} {r_reversible} ZnO + CO on the isotope effects on the carbon and oxygen atoms have also been calculated. (author) [French] Nous avons etudie les effets isotopiques qui ont lieu dans la reduction du gaz carbonique par le zinc. La validite de l'equation de Bernstein qui permet de calculer le facteur de fractionnement a ete demontree pour le cas d'une reaction irreversible de surface. Ces facteurs de fractionnement experimentaux sont en bon accord avec ceux obtenus par le calcul des fonctions de partition isotopiques des complexes actives adsorbes. Dans le mecanisme de reaction utilise, le modele du complexe active correspond a la dissociation d'une des liaisons carbone oxygene CO{sub 2} {yields} CO + O. Les effets perturbateurs de la reversibilite de la reduction Zn + CO{sub 2} {r_reversible} ZnO + CO sur les effets isotopiques du carbone et ceux de l'oxygene ont ete egalement evalues. (auteur)

  2. Description d'un nouveau brûleur compact. Fonctionnement en régime de gaz prémélangés Description of a New Compact Premixed Gas Burner

    Directory of Open Access Journals (Sweden)

    Minetti R.

    2006-11-01

    Full Text Available On décrit un nouveau brûleur compact à gaz, de haut rendement et d'une puissance variable de 1 à 5 kW. La source de chaleur est une flamme plate d'un prémélange stoechiométrique de gaz naturel et d'air stabilisé sur une grille d'une surface de 100 cm2. Plusieurs grilles en acier inoxydable sont comparées. Elles diffèrent par leur épaisseur, le nombre et la dimension des trous. Un échangeur de chaleur en laiton à circulation d'eau peut être approché jusqu'à 7 mm de la surface du brûleur. La température des gaz frais, le débit et la position de l'échangeur ont été modifiés et les conditions optimales de fonctionnement sont décrites. Les températures à travers les gaz frais, la flamme, les gaz brûlés et les fumées, ont été mesurées. Un modèle simple des échanges de chaleurs est présenté. Il permet une meilleure compréhension des processus de transfert et facilite le choix des conditions opératoires. Dans les meilleures conditions, 93 % du contenu thermique du mélange gazeux est transféré à l'échangeur. Some general characteristics of a compact and efficient gas burner are described (1-5 kW. The heat source is a premixed flat flame stabilized on a 100 cm2 grid fed by a stoechiometric mixture of air and natural gas. Various types of stainless steel grids have been investigated. They differ according to their thickness and to the number and size of the holes. A circulating water heat exchanger made of brass can be approached to the flame as close as 7 mm above the burner surface. The temperature of the inlet gas mixture, the flow rate, and the position of the heat exchanger have been varied. The best working conditions are given as well as the temperature through the fresh gaseous mixture, the temperature profiles of the flame and the temperature of the fumes. From heat transfer calculations a simple model is presented. It gives better insight into the heat transfer processes and facilitates a judicious

  3. Etudes préliminaires à la gazéification souterraine profonde des charbons. Perspectives et problèmes Preliminary Research on the Deep Underground Gasification of Coal. Outlook and Problems

    Directory of Open Access Journals (Sweden)

    Pottier M.

    2006-11-01

    Full Text Available Après création dans une couche de charbon d'une communication entre deux forages, la gazéification in situ vise à réaliser l'extraction de l'énergie du charbon grâce au soutirage par l'un des puits de gaz combustible résultant de la combinaison du charbon en place avec les réactifs gazeux injectés par l'autre puits. Si une méthode de mise en communication des forages peut être découverte pour des couches de charbon profondes (plus de 800 m il restera à déterminer comment conduire l'opération de gazéification et à évaluer la quantité de gaz, susceptible de méthanation, récupérable, dans un gisement donné, par un doublet de forages ; cette quantité gouverne en effet l'intérêt économique de l'opération. Un recensement des couches de charbon situées en France au delà de 800 m de profondeur, d'épaisseur au moins égale à 2 m et que rien n'empêche actuellement de considérer comme utilisables pour le procédé fournit une estimation totale, avec pondération suivant l'incertitude, de 2 milliards de tonnes. L'ampleur de ces ressources incite sur le plan français à s'efforcer d'établir si le procédé de gazéification souterraine permet leur récupération à un coût acceptable. Sur le plan mondial l'enjeu est, bien entendu, encore plus considérable. After a communication has been created between two boreholes in a Goal bed, insitu gasification is a way of trying to extract the energy contained tn the coal by with-drowing, via one of the wells, the combustible gas resulting from the combination of the Goal in place with gaseous reactants injected via the other well. If a method con be discovered for creating a communication betwen boreholes for deep Goal beds (deeper than 800 m, a method will still have ta be discovered for carrying out the gasification operation and for evaluating the amount of gas available for methanationthot is recoverable in a given deposit via a pair of boreholes. This amount effectively

  4. Improvements in gas supply systems for heavy-water moderated reactors; Etudes de perfectionnements aux systemes d'alimentation en gaz d'un reacteur modere a l'eau lourde

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, G.; Hassig, J.M.; Laurent, N.; Thomas, B. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    In a heavy-water moderated reactor cooled by pressurized gas, an important problem from the point of view, of the reactor block and its economics is the choice of the gas supply system. In the pressure tube solution, the whole of the reactor block structure is at a relatively low temperature, whereas the gas supply equipment is at that of the gas, which is much higher. These parts, through which passes the heat carrying fluid have to present as low a resistance as possible to it so as to avoid costly extra blowing power. Finally, they may only be placed in the reactor block after it has been built; the time required for putting them in position should therefore not be too long. The work reported here concerns the various problems arising in the case of each channel being supplied individually by a tube at the entry and the exit which is connected to a main circuit made up of large size collectors. This individual tubing is sufficiently flexible to absorb the differential expansion and the movement of its ends without stresses or prohibitive reactions being produced; the tubing is also of relatively short length so as to reduce the pressure head of the pressurized gas outside the channels; the small amount of space taken up by the tubing makes it possible to assemble it in a manner which is satisfactory from the point of view both of the time required and of the technical quality. (authors) [French] Dans un reacteur modere a l'eau lourde et refroidi au gaz sous pression, un probleme important du point de vue du trace du bloc pile et de son economie est le choix du systeme d'alimentation en gaz. Pour une solution a tubes de force, l'ensemble des structures du bloc reacteur est a temperature relativement faible, alors que les organes d'alimentation en gaz sont a celle, notablement plus elevee, du gaz. Ces organes, traverses par le debit du caloporteur, doivent lui opposer le minimum de resistance afin de ne pas necessiter un supplement onereux de

  5. Cost of wound treatment to increase significantly in Denmark over the next decade

    DEFF Research Database (Denmark)

    Hjort, Anne Mette; Gottrup, F

    2010-01-01

    To demonstrate that changes in demography, life expectancy and incidence of background diseases (including type 2 diabetes mellitus) during the period 2009-2020 will significantly increase the costs of wound care in Denmark.......To demonstrate that changes in demography, life expectancy and incidence of background diseases (including type 2 diabetes mellitus) during the period 2009-2020 will significantly increase the costs of wound care in Denmark....

  6. Climate and greenhouse effect gas: glaciated archives data. Climat et gaz a effet de serre: les donnees des archives glaciaires

    Energy Technology Data Exchange (ETDEWEB)

    Lorius, C. (Laboratoire de Glaciologie et Geophysique de l' Environnement, 38 - Saint-Martin-d' Heres (FR))

    1991-01-01

    Ice caps in Antarctica or Greenland have recorded the anthropogenic effect on atmospheric composition and especially on greenhouse effect gases such as carbon dioxide and methane. 2000 meter depth drilling samples allowed to study the climates for 150 000 years ago; hot and cold climates are ruled by periodic movement of the Earth around the sun and by more or less elevated concentration of greenhouse effect gases in the atmosphere. Prospects for to morrow climates and anthropogenic contribution are then possible.

  7. Recovering Energy at Entry of Natural Gas into Customer Premises by Employing a Counter-Flow Vortex Tube Récupération d’énergie à l’arrivée du gaz naturel dans les installations des usagers grâce à l’emploi d’un tube Vortex à contre-courant

    Directory of Open Access Journals (Sweden)

    Farzaneh-Gord M.

    2010-10-01

    Full Text Available Throttling valves are currently utilised to reduce high-pressure natural gas flowing through the distribution pipeline to the working level of customers’ equipment. This wastes valuable energy of the gas. Due to low natural gas consumption at customer premises, it is not feasible to utilise expansion machines. In this study, a new idea is proposed to take advantage of the Vortex Tube and natural gas pressure reduction. The idea is to replace the throttling valve with a Vortex Tube in the natural gas pressure reduction system and take advantage of the generated cooling capacity. An experimental investigation was made to determine the effects of the cold orifice diameter and the energy separation of the counter-flow Vortex Tube when air and natural gas are used as the fluid. The energy separation was investigated by use of the experimentally obtained data. La reduction de la pression de gaz naturel entre les conduites de distribution haute pression et les installations des usagers est aujourd’hui assuree par des vannes de reduction de pression. Ce dispositif entraine une perte importante du contenu energetique du gaz. Les installations des usagers consommant trop peu de gaz naturel pour envisager d’avoir recours a des dispositifs d’expansion, notre etude explore les avantages potentiels de l’utilisation d’un tube Vortex pour la reduction de la pression de gaz naturel. Il s’agit de remplacer la vanne de reduction de pression par un tube Vortex dans le dispositif de reduction de la pression de gaz naturel et de tirer profit de la capacite de refroidissement produite. L’etude experimentale avait pour objectif de determiner l’effet du diametre de l’orifice froid ainsi que de l’utilisation de l’air et du gaz naturel comme fluides sur la production d’energie dans le tube Vortex a contre-courant. Le taux de recuperation de l’energie est determine a partir des mesures experimentales.

  8. Project of law relative to the electricity and gas public utilities and to the power and gas companies; Projet de loi relatif au service public de l'electricite et du gaz et aux entreprises electriques et gazieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This document is the definitive text of this project of law adopted by the French house of commons. The aim of this law is to allow the administrations to avoid to use their eligibility right with the opening of the electricity and gas markets to competition. It changes the juridical status of the two public utilities Electricite de France (EdF) and Gaz de France (GdF) into two anonymous companies and creates two additional companies for the management of the power and gas networks. It ensures also the transposition of the European directives from June 26, 2003 (2003/54/CE and 2003/55/CE). It contains some proper dispositions and modifies various existing French laws, in particular the law no. 46-628 from April 8, 1946 about the electricity and gas nationalization and the law no. 2000-108 from February 10, 2000 relative to the modernization and development of the electric public utility. (J.S.)

  9. Model-Based Throttle Control using Static Compensators and Pole Placement Commande des gaz basée sur un modèle utilisant des compensateurs statiques et un placement de pôles

    Directory of Open Access Journals (Sweden)

    Thomasson A.

    2011-10-01

    Full Text Available In modern spark ignited engines, the throttle is controlled by the Electronic Control Unit (ECU, which gives the ECU direct control of the air flow and thereby the engine torque. This puts high demands on the speed and accuracy of the controller that positions the throttle plate. The throttle control problem is complicated by two strong nonlinear effects, friction and limp-home torque. This paper proposes the use of two, simultaneously active, static compensators to counter these effects and approximately linearize the system. A PID controller is designed for the linearized system, where pole placement is applied to design the PD controller and a gain scheduled I-part is added for robustness against model errors. A systematic procedure for generating compensator and controller parameters from open loop experiments is also developed. The controller performance is evaluated both in simulation, on a throttle control benchmark problem, and experimentally. A robustness investigation pointed out that the limp-home position is an important parameter for the controller performance, this is emphasized by the deviations found in experiments. The proposed method for parameter identification achieves the desired accuracy. Au sein des moteurs à allumage commandé modernes, les gaz sont régulés par le boîtier de commande électronique (ECU; Electronic Control Unit, qui permet la régulation directe par l’ECU du flux d’air et ainsi du couple moteur. Cela conduit à des exigences élevées quant à la vitesse et à la précision du régulateur qui positionne le papillon des gaz. Le problème de commande des gaz est compliqué par deux forts effets non linéaires, le frottement et le couple de mode de secours (“limp-home”. Cet article propose l’utilisation de deux compensateurs statiques, actifs simultanément, pour contrer ces effets et linéariser approximativement le système. Un régulateur PID est conçu pour le système linéarisé, où un

  10. High Pressure Behavior of Hydrocarbons. Joule-Thomson Expansion of Gas Condensates Comportement des hydrocarbures à haute pression. Détente de Joule-Thomson de gaz à condensats

    Directory of Open Access Journals (Sweden)

    Kortekaas W. G.

    2006-12-01

    Full Text Available This paper presents calculations of Joule-Thomson inversion effects in high-pressure-high-temperature gas condensates. Isenthalpic expansions were modeled for several gas condensate mixtures reported in literature using the Soave-Redlich-Kwong and the Peng-Robinson equations of state. The calculations confirmed qualitatively the heating of gas condensates at expansion. Although reservoir temperatures are in the region where cooling occurs, i. e. , inside the inversion curve, it was shown that reservoir pressures lie outside this region, and that the temperature will increase until the inversion curve is reached. The calculated temperature increases are not very large. Although exact values depend on fluid composition, reservoir conditions, and pressure drop, typical calculated temperature increases are in the range of 10-30°C for reservoir pressures of 1000 bar. A sensitivity study showed that both reservoir pressure and fluid composition greatly affect the temperature increase. With increasing pressures and increasing amounts of heavy constituents present in gas condensate mixtures, the maximum possible temperature effect will also increase. Unfortunately, due to lack of experimental information, the reliability of the calculated results could not be verified. Cet article présente des calculs de l'effet d'inversion de Joule-Thomson pour des gaz à condensats à haute température et haute pression. La détente isenthalpique a été modélisée pour plusieurs compositions de gaz à condensats trouvées dans la littérature, en utilisant les équations d'état de Soave-Redlich-Kwong et de Peng-Robinson. Ces calculs confirment qualitativement le réchauffement des gaz à condensat lors de la détente. Bien que les températures de gisement se trouvent dans la région où un refroidissement s'observe, c'est-à-dire à l'intérieur de la courbe d'inversion, on a montré que les pressions de gisement correspondent à l'extérieur de cette r

  11. GAZ ABSORPSİYONUNDA KULLANILABİLİR SCHIFF BAZI-METAL KOMPLEKSLERİNİN KUARTZ KRİSTAL MEMBRAN SENSÖRÜ OLARAK GELİŞTİRİLMESİ

    OpenAIRE

    NAZIR, Hasan

    1990-01-01

    Bu çalışmada, gravimetrik sensör uygulamalarından biri olan Kuartz Kristal Mikrobalans (QCM; Quartz Crystal Microbalance) sisteminin elle taşınabilir, pille de çalışabilen ve bilgisayar ile kontrol edilebilir küçük bir modülünün geliştirilmesi, sentezlenecek Schiff bazı-metal kompleksleriyle de sistemin gaz fazında çalışmasının test edilmesi amaçlanmıştır. QCM sistemi temel olarak üç ana parçadan oluşmaktadır; Frekansmetre, kristal ösilatör ve SiO2 kristali. Yapılan çalışmada, PIC (Peripheral...

  12.  Standardy rachunkowości stanowiące podstawę sporządzania sprawozdań finansowych przez jednostki wydobywające gaz łupkowy w Polsce i w Stanach Zjednoczonych

    Directory of Open Access Journals (Sweden)

    Anna Galimska

    2015-12-01

    Full Text Available Celem artykułu jest analiza oraz porównanie standardów rachunkowości wykorzystywanych przez przedsiębiorstwa poszukujące i wydobywające gaz łupkowy w Stanach Zjednoczonych i w Polsce. Autorka dokonała zestawienia regulacji służących do sporządzania i prezentacji sprawozdań finansowych, na których opierają się jednostki eksploatujące węglowodory niekonwencjonalne. Wciąż postępujący rozwój rynków kapitałowych znajduje swoje odzwierciedlenie w intensyfikacji oczekiwań interesariuszy względem atrybutów, którymi winny charakteryzować się sprawozdania finansowe. Rozważania zawarte w artykule ukazują wysoki poziom specjalizacji amerykańskich standardów rachunkowości, na których bazują podmioty wydobywające gaz łupkowy w Stanach Zjednoczonych. Natomiast standardy międzynarodowe poruszają jedynie kwestię początkowego stadium procesu wydobycia alternatywnych węglowodorów, co rzutuje na spójność przygotowywanych na ich podstawie sprawozdań finansowych. Ponadto istotna jest kwestia rozbieżności merytorycznych czy też interpretacyjnych analizowanych standardów zarówno w zakresie identyfikacji kosztów oraz ich klasyfikacji, jak i określania wysokości odpisów z tytułu utraty wartości.

  13. Karabük İlindeki Hava Kirliliğinin Doğal Gaz Kullanımı İle Değişimi

    Directory of Open Access Journals (Sweden)

    Abdülaziz YILDIZ

    2012-12-01

    Full Text Available ÖzetFosil kaynaklı yakıtların kullanımı, hava kirliliğine sebebiyet veren en önemli unsurlardan bir tanesidir. Bu yakıtların bilinçsizce kullanılması sonucunda çevre problemlerine özellikle de hava kirliliğine neden olmaktadır. Yapılan bu çalışmada, Karabük ilinin doğalgaz kullanmaya başlamadan önceki ve doğalgaza geçiş ile hava kirlilik parametreleri (SO2 ve PM10 incelenmiştir. Doğal gaz kullanımının hava kalitesine etkisi araştırılmıştır. İlde ısınma ihtiyacını karşılamak için kömür, fuel-oil ve mazot kullanılırken 2010 yılı itibariyle doğal gaza geçilmiştir. Doğal gazın kullanılmaya başlanmasıyla bu yakıtların kullanımı azalmıştır. Çalışmanın sonunda, Hava Kalitesi Değerlendirme ve Yönetimi Yönetmeliğinde (HKDYY belirtilen, SO2 için 250 μg/m3 değerinin doğal gaz kullanımına geçilmeden önce bazı aylarda üzerinde olduğu görülmüş ve doğal gaz kullanılmaya başlanmasından sonraki dönemlerde ise 250 μg/m3 değerinin aşılmadığı görülmüştür. PM10 için yönetmelikte belirtilen 200 μg/m3 değerinin kış sezonunda aşıldığı tespit edilmiştir. 2010 yılında Doğal gaz kullanımına geçiş ile birlikte bu değerde tekrar bir düşüş gözlenmiştir. Doğal gaz kullanım oranı artıkça havadaki SO2 ve PM10 değerlerinde ciddi düşüşler olduğu gözlenmiştir.AbstractThe Usage of fossil origin fuels is one of the most important cause of air pollution. The usage of these fuels unconsciously causes environmental problems especially air pollution. In this study air pollution parameters (SO2 ve PM10 were analyzed before and after the usage of natural gas in Karabuk. The effect of usage natural gas on air quality is researched. In this city before 2010 coal, foul-oil and diesel were used to provide heat demanded then it is started using natural gas by 2010.With starting the usage of natural gas, the usage of these kind of fuels (coal, foul

  14. Visual Investigation of Retrograde Phenomena and Gas Condensate Flow in Porous Media Étude visuelle des phénomènes rétrogrades et de l'écoulement des gaz de condensat en milieux poreux

    Directory of Open Access Journals (Sweden)

    Danesh A.

    2006-11-01

    Full Text Available The mechanism of retrograde condensation and the flow of gas-condensate in horizontal porous media under simulated reservoir conditions were visually studied. Two-dimensional glass micromodels with homogeneous pore structures, as well as heterogeneous patterns, reproduced from real rock micrographs were employed in this study. Depletion tests were carried out using synthetic multicomponent hydrocarbon gas mixtures and also a North Sea gas condensate. The multiphase flow behaviour of the tested systems, as observed and recorded on video, is presented here along with the measured data. In water-wet pores, condensate was observed to be formed as a continuous thin film on connate water, which was the preferred site for condensation. Pressure reduction below the system cricondenbar resulted in the growth of the condensate almost exclusively on water rings at pore throats and dead end pores. The condensate was observed to flow through thin films even at low saturations, with little contribution to the condensate recovery. The rate of pressure depletion influenced the gas flow shear and was found to strongly affect the condensate propagation. Local instabilities could promote significant condensate movement in pore sections which would only be retarded further downstream by capillary effects diminishing the condensate recovery. Relative permeability-saturation relation-ships for gas-condensate flow should not be expected to take the same form as the oil-gas relative permeability for solution gas or external gas drive. Le mécanisme de la condensation rétrograde et l'écoulement des gaz de condensat en milieu poreux horizontal dans une simulation des conditions naturelles ont fait l'objet d'études visuelles. Des micromodèles en verre bi-dimensionnels à structure poreuse homogène, et des éléments hétérogènes reproduisant des micrographies de roches réelles, ont été utilisés pour cette étude. Des essais d'épuisement ont été effectu

  15. Energy Equation Derivation of the Oil-Gas Flow in Pipelines Dérivation de l’équation d’énergie de l’écoulement huile-gaz dans des pipelines

    Directory of Open Access Journals (Sweden)

    Duan J.M

    2012-09-01

    well describe the oil-gas two-phase flow. Lors de la simulation d’un écoulement multiphasique huile-gaz dans une conduite, le calcul thermodynamique représente un processus important en interaction avec le calcul hydraulique; il influence la convergence du programme et la précision des résultats. La forme de l’équation d’énergie constitue la clef du calcul thermodynamique. Basée sur l’équation d’énergie de l’écoulement huile-gaz dans un pipeline, la formule de chute de température explicite (ETDF; Explicit Temperature Drop Formula est dérivée pour un calcul de température d’état stable huile-gaz. Cette nouvelle équation d’énergie prend en compte de nombreux facteurs, tels que l’effet Joule-Thomson, le travail de pression, le travail de frottement, ainsi que l’incidence des ondulations de terrain et le transfert de chaleur avec le milieu extérieur le long de la ligne. Ainsi, il s’agit d’une forme globale de l’équation d’énergie, laquelle pourrait décrire précisément la réalité d’un pipeline à phases multiples. Pour cette raison, un certain nombre de points de vue de la littérature à propos du calcul de température d’un écoulement diphasique huile-gaz dans des pipelines sont passés en revue. L’élimination de la boucle d’itération de température et l’intégration de l’équation de température explicite, au lieu de l’équation d’énergie d’enthalpie, dans le calcul conjugué hydraulique et thermique, se sont avérées améliorer l’efficacité de l’algorithme. Le calcul a été appliqué non seulement au modèle de composants mais aussi au modèle Black-Oil. Ce modèle est incorporé respectivement dans le modèle de composants ainsi que le modèle Black-Oil et deux simulations sont effectuées sur deux pipelines en service, les pipelines multiphasiques Yingmai-Yaha et Lufeng; les résultats de température sont comparés à la simulation calculée par OLGA et aux résultats mesurés. Il

  16. Reconsideration of Methane Isotope Signature As a Criterion for the Genesis of Natural Gas: Influence of Migration on Isotopic Signatures Reconsidération de la signature isotopique du méthane comme critère pour la genèse du gaz naturel : influence de la migration sur les signatures isotopiques

    Directory of Open Access Journals (Sweden)

    Pernaton E.

    2006-11-01

    Full Text Available Experiments were performed in the purpose of studying the isotopic consequences of the diffusional transport of hydrocarbon gases through sediment rocks. Linked to a numerical model, these gas diffusion experiments through a shale porous plug allowed us to correlate porosity and diffusivity of the migration medium. Significant isotopic fractionations (carbon and hydrogen of methane, and ethane at a lesser degree were observed. This is in contradiction with the actual dogma of isotope geochemistry of natural gases which claims that no fractionation occurs during gas migration. The genetic characterization of natural gases by using the isotopic signature of methane appears as an ambiguous method. Plusieurs expériences ont été réalisées dans le but d'étudier les conséquences isotopiques du transport par diffusion des gaz hydrocarbures au travers des roches sédimentaires. Associées à un modèle numérique, ces expériences de diffusion au travers d'une membrane d'argile reconstituée nous ont permis de corréler deux paramètres pétrophysiques du milieu de migration : la porosité et la diffusivité. D'importants fractionnements isotopiques ont été observés au cours de la diffusion du méthane et, à plus petite échelle, lors de la diffusion de l'éthane. Ces résultats remettent en cause le dogme actuel de la géochimie isotopique des gaz naturels qui stipule que la migration des gaz ne peut induire de fractionnements isotopiques. En conséquence, les méthodes de caractérisation génétique des gaz naturels utilisant la signature isotopique du méthane apparaissent comme insuffisantes.

  17. Analysis of Simultaneous Gas-Liquid Flow Through an Orifice and Its Application to Flow Metering Etude de l'écoulement simultané d'un mélange gaz-liquide à travers un orifice et son application à la mesure du débit

    Directory of Open Access Journals (Sweden)

    Pascal H.

    2006-11-01

    Full Text Available The purpose of this article is to show a more accurate orifice equation for a two-phase flow, such a compressible mixture of gas and liquid. The orifice equation given here con be used for the measurement of a gas-liquid mixture of fine emulsions by the orificemeter method. From the thermodynamic point of view, an equation of state has been formulated which provides the relationship between the specific mass of the mixture and pressure, under conditions of adiabatic expansion. The results obtained enable the mass flow rates of gas and liquid ta be determined without separation of the phases, provided thot the gas liquid mass ratio is known. The critical pressure ratio corresponding ta sonic velocity is also determined. Cet article présente une relation plus précise pour l'écoulement d'un système à deux phases, tel qu'un mélange compressible gaz-liquide, à travers un diaphragme. Cette relation peut être utilisée pour des mesures de mélanges gaz-liquide très finement divisés, c'est-à-dire des émulsions ou brouillards, par la méthode du diaphragme en paroi mince. Du point de vue thermodynamique, on a formulé une équation d'état donnant la relation entre la masse spécifique du mélange et la pression dans des conditions d'expansion adiabatique. Les résultats obtenus per-mettent de déterminer le débit massique du gaz et du liquide, sans séparation des deux phases, à condition que le rapport de masse gaz-liquide soit connu. On détermine également le rapport de pression critique correspondantà la vitesse du son.

  18. Algeria facing the challenges of Europe natural gas supply and the respect of the environment.; L'Algerie face aux defis de l'approvisionnement de l'Europe en gaz naturel et le respect de l'environnement

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Nadia Nait

    2010-09-15

    Taking into account the expectations, for the next decades, of a strong increase in the demand for gas in Europe, Algeria has committed to large structuring projects, adding to the two gas pipeline linking Algeria to Spain via Morocco and Algeria to Italy via Tunisia. Two more undertakings are added linking Algeria directly to two European partners. Sonatrach will play an important role in global environment protection, natural gas being less polluting than oil and coal and emitting less co2. Substitution of coal by natural gas will generate socio economical advantages and will preserve the environment. [French] Compte tenu des attentes, pour les decennies prochaines, d'une forte croissance de la demande de gaz en Europe, l'Algerie s'est engagee dans de grands projet structurants s'ajoutant aux deux gazoducs reliant l'Algerie a l'Espagne via le Maroc et l'Algerie a l'Italie via la Tunisie, viennent s'ajouter deux autres ouvrages reliant directement l'Algerie a deux partenaires europeens. Sonatrach Jouera un role important dans la protection de l'environnement a l'echelle mondiale, le gaz naturel est moins polluants que le petrole, le charbon et emet moins de co2. La substitution du charbon par le gaz naturel generera des avantages socio-economiques, preservation de l'environnement.

  19. Fluctuations Magnetiques des Gaz D'electrons Bidimensionnels: Application AU Compose Supraconducteur LANTHANE(2-X) Strontium(x) Cuivre OXYGENE(4)

    Science.gov (United States)

    Benard, Pierre

    Nous presentons une etude des fluctuations magnetiques de la phase normale de l'oxyde de cuivre supraconducteur La_{2-x}Sr _{x}CuO_4 . Le compose est modelise par le Hamiltonien de Hubbard bidimensionnel avec un terme de saut vers les deuxiemes voisins (modele tt'U). Le modele est etudie en utilisant l'approximation de la GRPA (Generalized Random Phase Approximation) et en incluant les effets de la renormalisation de l'interaction de Hubbard par les diagrammes de Brueckner-Kanamori. Dans l'approche presentee dans ce travail, les maximums du facteur de structure magnetique observes par les experiences de diffusion de neutrons sont associes aux anomalies 2k _{F} de reseau du facteur de structure des gaz d'electrons bidimensionnels sans interaction. Ces anomalies proviennent de la diffusion entre particules situees a des points de la surface de Fermi ou les vitesses de Fermi sont tangentes, et conduisent a des divergences dont la nature depend de la geometrie de la surface de Fermi au voisinage de ces points. Ces resultats sont ensuite appliques au modele tt'U, dont le modele de Hubbard usuel tU est un cas particulier. Dans la majorite des cas, les interactions ne determinent pas la position des maximums du facteur de structure. Le role de l'interaction est d'augmenter l'intensite des structures du facteur de structure magnetique associees a l'instabilite magnetique du systeme. Ces structures sont souvent deja presentes dans la partie imaginaire de la susceptibilite sans interaction. Le rapport d'intensite entre les maximums absolus et les autres structures du facteur de structure magnetique permet de determiner le rapport U_ {rn}/U_{c} qui mesure la proximite d'une instabilite magnetique. Le diagramme de phase est ensuite etudie afin de delimiter la plage de validite de l'approximation. Apres avoir discute des modes collectifs et de l'effet d'une partie imaginaire non-nulle de la self-energie, l'origine de l'echelle d'energie des fluctuations magnetiques est examinee

  20. Sensibilité à la température d'un capteur de pression partielle de gaz carbonique à fibres optiques

    Science.gov (United States)

    Bendamardji, S.; Alayli, Y.

    1998-03-01

    An optical fibre sensor to measure weak partial pressures of carbon dioxide has been designed and realized. This sensor is based on direct molecular absorption in the near infrared at 4.3 μ{m}. It is an extrinsic and amplitude modulation type sensor. In the linear region between 0 and 2000μbar, the calibration curve that represents the transmitted power versus the carbon dioxide partial pressure in air shows a sensitivity of 20 nW/mbar with a minimum detectable pressure of 25 μbar. This article describes a temperature sensitivity analysis for all optoelectronic components and proposes a calculation method to distinguish two successive levels of partial pressure in a surrounding atmosphere where the temperature can vary. The experimental results show that without using a reference signal, the maximum variation of temperature is ± 1.4^circC. The use of a reference signal combined with thermoelectric cooling of the photodetector tolerates a temperature variation of ± 25^circC. Un capteur à fibres optiques permettant la mesure de faibles pressions partielles de gaz carbonique a été conçu et réalisé. Ce capteur basé sur l'absorption moléculaire directe dans l'infrarouge à 4,3μ m est de type extrinsèque à modulation d'amplitude. Dans la région linéaire entre 0 et 2000 μbar, la courbe d'étalonnage représentant la puissance transmise en fonction de la pression partielle de CO_2 dans l'air montre une sensibilité de 20 nW/mbar avec une pression minimale de détection de 25 μbar. Cet article concerne une analyse de sensibilité à la température de l'ensemble des constituants optoélectroniques du capteur en proposant une méthode de calcul qui permette de discerner deux niveaux successifs de pression partielle dans un environnement assujetti à une variation de la température. Les résultats expérimentaux montrent que, sans utilisation d'un signal de référence, la variation maximale de température admise est de ± 1,4^circC alors que l

  1. 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

  2. Glaz da glaz ili gaz da gaz? / Jevgenija Garanzha

    Index Scriptorium Estoniae

    Garanža, Jevgenija, 1979-

    2005-01-01

    Euroopa Liidu ja Venemaa tippkohtumisest Londonis, kõnealusteks teemadeks lihtsustatud viisarežiim, piirilepingud Eesti ja Lätiga, vähemusrahvuste olukord nendes riikides, põhiteemaks kujuneb Euroopa sõltuvus Venemaa gaasist ja naftast

  3. Glaz da glaz ili gaz da gaz? / Jevgenija Garanzha

    Index Scriptorium Estoniae

    Garanža, Jevgenija, 1979-

    2005-01-01

    Euroopa Liidu ja Venemaa tippkohtumisest Londonis, kõnealusteks teemadeks lihtsustatud viisarežiim, piirilepingud Eesti ja Lätiga, vähemusrahvuste olukord nendes riikides, põhiteemaks kujuneb Euroopa sõltuvus Venemaa gaasist ja naftast

  4. Méthode analytique généralisée pour le calcul du coning. Nouvelle solution pour calculer le coning de gaz, d'eau et double coning dans les puits verticaux et horizontaux Generalized Analytical Method for Coning Calculation. New Solution to Calculation Both the Gas Coning, Water Coning and Dual Coning for Vertical and Horizontal Wells

    Directory of Open Access Journals (Sweden)

    Pietraru V.

    2006-11-01

    Full Text Available Une nouvelle méthode analytique d'évaluation du coning d'eau par bottom water drive et/ou de gaz par gas-cap drive dans les puits horizontaux et verticaux a été développée pour les réservoirs infinis [1]. Dans cet article, une généralisation de cette méthode est présentée pour les réservoirs confinés d'extension limitée dont le toit est horizontal. La généralisation proposée est basée sur la résolution des équations différentielles de la diffusivité avec prise en compte des effets de drainage par gravité et des conditions aux limites pour un réservoir confiné. La méthode est applicable aux réservoirs isotropes ou anisotropes. L'hypothèse de pression constante à la limite de l'aire de drainage dans l'eau et/ou dans le gaz a été adoptée. Les pertes de charge dans l'aquifère et dans le gas-cap sont donc négligées. Les principales contributions de cet article sont : - L'introduction de la notion de rayon de cône, différent du rayon de puits. La hauteur du cône et le débit critique dépendent du rayon de cône alors qu'ils sont indépendants du rayon du puits. - Une nouvelle corrélation pour le calcul du débit critique sous forme adimensionnelle en fonction de trois paramètres : le temps, la longueur du drain horizontal (nulle pour un puits vertical et le rayon de drainage. - Des corrélations pour le calcul du rapport des débits gaz/huile (GOR ou de la fraction en eau (fw, pendant les périodes critique et postcritique, qui tiennent compte de la pression capillaire et des perméabilités relatives. - Des corrélations pour le calcul des rapports de débits gaz/huile et eau/huile pendant les périodes pré, post et supercritique en double coning. - Des critères pour le calcul du temps de percée au puits en simple coning de gaz ou d'eau, ou en double coning de gaz et d'eau. A new analytical method for assessing water and/or gas coning in horizontal and vertical wells has been developed for infinite

  5. Druzhba - druzhboi, a gaz vroz

    Index Scriptorium Estoniae

    2006-01-01

    Gazpromi kavatsusest tõsta Valgevenele müüdava gaasi hinda. Gaasigigandi strateegiline eesmärk - Valgevene gaasitranspordivõrgu kontrolli alla saamine, ei ole seni õnnestunud, lähiaastail ootab gaasi hinnatõus ka Balti riike

  6. Measurement of the activity of beta emitting gases using an ionisation chamber; Mesure de l'activite des gaz emetteurs beta au moyen d'une chambre d'ionisation

    Energy Technology Data Exchange (ETDEWEB)

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

    1962-07-01

    An ionization chamber was developed for measuring directly the activity of a {beta}-emitting gas whatever the gas may be. The following two parameters are defined and determined: p, the average specific ionization produced by a {beta} disintegration, and i, the average {beta} path in the chamber. It was shown, during the determination of i, that the {beta} particles are reflected on the walls of the ionization chamber when the latter are made of a high atomic number material. It was possible to eliminate this effect by constructing an electrode chamber made of graphite. With this chamber a direct measurement can be made of the activity of a gaseous {beta} emitter with a precision of about {+-}10%. Some applications are given of the graphite electrode chamber (calibration of the chambers built industrially and determination of the activation cross section of a gaseous emitter). It was possible to determine the activation cross section of {sup 134}Xe; a value of 0.18 {+-} 0.03 barn was found. (author) [French] Le but de l'etude est de realiser une chambre d'ionisation permettant d'effectuer une mesure directe de l'activite d'un gaz emetteur {beta} quel que soit l'emetteur considere. On definit et l'on determine les deux parametres suivants: p: ionisation specifique moyenne produite par une desintegration {beta}. La determination est effectuee par une methode graphique, i: moyenne des parcours des {beta} dans la chambre. La determination est effectuee experimentalement par introduction dans la chambre d'un gaz radioactif dont on peut calculer l'activite. On a mis en evidence, au cours de la determination de i, la reflexion des particules {beta} sur les parois des chambres d'ionisation lorsque celles-ci sont constituees d'un materiau de numero atomique eleve. La construction d'une chambre a electrodes de graphite nous a permis d'eliminer ce phenomene. Avec cette chambre, on effectue une mesure directe de

  7. Eskişehir’de Hava Kirliliği ve Doğal Gazın Tarihçesi: Genel Değerlendirme / History of Air Pollution and Natural Gas Usage in Eskişehir: A General Review

    Directory of Open Access Journals (Sweden)

    Nazmi Oruç

    2012-12-01

    şehir temiz hava planı (2011-2014 hazırlanmıştır. Partikül Madde ve SO2 yanında NO2,O3 ve PAH gibi kirleticilerin ve ulaşım araçlarının neden olduğu kirliliğin de irdelendiği bu raporda, Eskişehir için ulusal yasal sınır değerleri zorlayan bir durum söz konusu olmasa da geniş ölçekte Avrupa Birliği ve Dünya Sağlık Örgütü (DSÖ gibi kuruluşların oluşturmuş olduğu standartların üzerinde değerlere rastlandığı kaydedilmektedir. Hava kirliliğinin önlenmesi amacıyla doğal gaz kullanımına ilk kez Eskişehir Organize Sanayi Bölgesinde (EOSB Botaş bünyesinde 1990 yılında başlanılmış daha sonra bu hizmet özelleştirme kapsamı içerisinde 2004 yılında Eskişehir Doğal Gaz Dağıtım A.Ş. (ESGAZ firmasına devredilmiştir. ESGAZ, Büyükşehir Belediyesi mücavir alanlarda yer alan imara açık tüm cadde ve sokaklara doğal gaz hizmeti vermekte olup 2004 yılında devir alınan 107.000 bağımsız birim sayısını 2011 yılı sonu itibariyle 300.000’e çıkartmıştır. EOSB bölgesi hariç evsel ve şehir içi sanayi tüketimi de 2005 yılında 211.756.888 m3 iken, 2011 yılında 348.974.147 m3’e çıkmıştır. Tüm bu olumlu gelişmelere karşın doğal gaz alt yapısı bulunan bazı semt ve apartmanlarda günümüzde de ithal ve yerli kömür kullanılması zaman zaman hava kirliliğine neden olmaktadır. İlk aşamada kent merkezinde özellikle kış aylarında kömür yerine tamamen doğal gaza geçilmesi ve ulaşım kaynaklı hava kirliğinin azaltılması için gereken önlemlerin alınması önerilmiştir. History of Air Pollution and Natural Gas Usage in Eskişehir: A General Review The aim of this study is to investigate the use of natural gas and air pollution levels in Eskişehir City Center in the last 30 years. Air pollution has been phenomena in Eskişehir since the beginning of 1980s, due to the use of low quality coal, unplanned and irregular urbanization and negative climate factors. First air

  8. Inverse periodic shadowing properties

    CERN Document Server

    Osipov, Alexey V

    2011-01-01

    We consider inverse periodic shadowing properties of discrete dynamical systems generated by diffeomorphisms of closed smooth manifolds. We show that the $C^1$-interior of the set of all diffeomorphisms having so-called inverse periodic shadowing property coincides with the set of $\\Omega$-stable diffeomorphisms. The equivalence of Lipschitz inverse periodic shadowing property and hyperbolicity of the closure of all periodic points is proved. Besides, we prove that the set of all diffeomorphisms that have Lipschitz inverse periodic shadowing property and whose periodic points are dense in the nonwandering set coincides with the set of Axiom A diffeomorphisms.

  9. Your First Period

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Your First Period (Especially for Teens) Home For Patients Search FAQs ... Teens) FAQ049, May 2015 PDF Format Your First Period (Especially for Teens) Especially For Teens What is ...

  10. Middle Helladic Period

    DEFF Research Database (Denmark)

    Sarri, Kalliopi

    1999-01-01

    The Middle Bronze Age on Mainland Greece is also known as the Middle Helladic period. The chronological framework of this period extends from the beginnings of the second millenium - roughly 1900 - until 1550 BC, that is until the beginnings of the Mycenaean period. The Middle Helladic period...... is considered as the dark period of the cultural decline. The remains of the material culture reveal a clear retrogression while the information available on the social stratification and economy are so few and problematic in interpretation that this period is considered as the "Middle Age of Greek Prehistory......". About 1900 BC, the period during which the first palaces of Crete were being built, Mainland Greece was entering a long period of decline during which economic features changed radically. A large number of metals and imported products became particularly rare while composite forms of economic...

  11. ON PERIODIC DYNAMICAL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    LU WENLIAN; CHEN TIANPING

    2004-01-01

    The authors investigate the existence and the global stability of periodic solution for dynamical systems with periodic interconnections, inputs and self-inhibitions. The model is very general, the conditions are quite weak and the results obtained are universal.

  12. Absorption air conditioning press kit: natural gas air conditioning - market shows Gaz de France's falling back, technologies - absorption heat pumps are coming to France, heat recovery - free energy for a waste processing facility, natural gas air conditioning - ideal temperature in the departments of a supermarket, teaching - an absorption machinery in a college of Marseille; Dossier Absorption: clim au gaz - le marche accuse le repli de gaz de France, technologies - les pompes a chaleur a absorption arrivent en France, recuperation de chaleur - de l'energie gratuite pour un centre de traitement des dechets, climatisation au gaz naturel - temperature ideale dans les rayons d'un supermarche, enseignement - une machine a absorption dans un lycee de Marseille

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, J.; Maes, P.

    2005-03-01

    The reorganization of Gaz de France (GdF) company (the former historical French gas utility) in the framework of the opening of energy markets has deeply changed the natural gas air conditioning sector. The professionals now have to promote this solution without the active sustain of GdF. The natural gas air conditioning technologies should develop in Europe in the coming years. The electricity prices and the necessity to reduce the summer consumption play in favor of natural gas. The ability of absorption air conditioning to valorize various heat sources is in good agreement with the sustainable development prospects and is one of the promotion way chosen in France by absorption equipment retailers. This press kit about absorption air conditioning systems comprises 5 articles dealing with: the natural gas air conditioning market in France, the start-up of absorption heat pumps commercialization in France, the in-situ valorization of wood wastes for the space heating and air conditioning at the municipal waste sorting facility of Plantaurel (Ariege, France), the natural gas air conditioning of a supermarket in Gap (Southern Alps, France), and a pedagogical gas air-conditioning facility in a technical college of Marseille (France). (J.S.)

  13. Production of Methanol-Higher Alcohol Mixtures from Natural Gas via Syngas Chemistry Production de mélanges méthanol-alcools supérieurs à partir du gaz, via (CO + H2

    Directory of Open Access Journals (Sweden)

    Courty P.

    2006-11-01

    Full Text Available Despite the prevailing position of ethers (MTBE, TAME as octane boosters, and the low oil prices at present, alcohol synthesis remains one of the near future means of natural gas upgrading via syngas chemistry. After a review of the available process development data in the field, this paper focuses on the IFP process studies, based on the CuCo and CuNi catalysts developed by Institut Français du Pétrole (IFR, France and Idemitsu Kosan (Japan. The adequacy between the product specifications, and the optimization of the performances is then discussed in a technico-economic context, together with a presentation of lab scale, pilot scale and demonstration scale test results. As a conclusion, a prospective overall view brings together todays economics and some improvement guidelines dealing with investments, operating cost and catalyst performances. Cette publication présente les travaux de R & D (Recherche et Développement menés par l'Institut Français du Pétrole (IFP, France et Idemitsu Kosan (Japon en synthèse d'alcools. Elle situe les résultats dans le contexte technique et économique actuel. L'accroissement constant des ressources prouvées en gaz et, chronologiquement, les deux crises pétrolières, la suppression du plomb dans les essences, ont conduit le monde industriel à intensifier les recherches concernant la synthèse d'alcools. Très récemment, les effets bénéfiques de l'addition d'alcools sur les émissions de polluants ont été mis en évidence. Toutefois, l'additivation de carburants par les alcools est en voie de disparition au profit des éthers, alors que, indépendamment, les procédés de production d'ammoniac, de méthanol, d'acide acétique, également fondés sur le gaz, se sont seuls développés. La synthèse d'alcools a fait l'objet de nombreux travaux, résumés dans les tableaux 1 et 2. L'étude des différents aspects réactionnels amène à prendre en compte l'exothermicité importante des r

  14. Community College Periodicals.

    Science.gov (United States)

    Pederson, Eldor O.

    Drawing from an examination of community college periodicals, their availability and characteristics, the academic affiliations of contributing authors, and the topics of their articles, this paper discusses the minor role which community college periodicals appear to play. A list of 35 periodicals dealing primary with community college education…

  15. Few period quasisymmetric stellarators

    Energy Technology Data Exchange (ETDEWEB)

    Isaev, M.Y.; Mikhailov, M.I.; Shafranov, V.D.; Subbotin, A.A. [Russian Research Centre `Kurchatov Institute`, Moscow (Russian Federation); Cooper, W.A. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP); Medvedev, S.Y. [Keldysh Inst. of Applied Mathematics, Russian Academy of Sciences, Moscow (Russian Federation)

    1997-06-01

    The results of plasma equilibrium and local stability investigations in two and four-period quasisymmetric stellarators are presented. A near-axis approximation is used for 2-period systems and the 3D codes VMEC and TERPSICHORE are used for four-periods devices to optimise the configurations. (author) 4 figs., 8 refs.

  16. The Periodic Pyramid

    Science.gov (United States)

    Hennigan, Jennifer N.; Grubbs, W. Tandy

    2013-01-01

    The chemical elements present in the modern periodic table are arranged in terms of atomic numbers and chemical periodicity. Periodicity arises from quantum mechanical limitations on how many electrons can occupy various shells and subshells of an atom. The shell model of the atom predicts that a maximum of 2, 8, 18, and 32 electrons can occupy…

  17. Tariff proposal of the Commission of energy regulation from February 28, 2008 for the use of public natural gas distribution networks; Proposition tarifaire de la Commission de regulation de l'energie du 28 fevrier 2008 pour l'utilisation des reseaux publics de distribution de gaz naturel

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    With the complete opening of natural gas markets to competition and the legal separation of distribution networks, Gaz de France Reseau Distribution requested the implementation of a new tariff of use of gas distribution networks to the Commission of energy regulation (CRE). A new tariff of networks utilisation has thus been proposed by CRE after a public consultation and the audition of gas suppliers. This tariff foresees a 5.6% increase of the present day tariff by July 1, 2008. The impact on the end-users' gas retail price will be a 1.5% rise of the regulated tariff. (J.S.)

  18. Periodicity of chaotic solutions

    CERN Document Server

    Berezowski, Marek

    2016-01-01

    The scope of the paper is the analysis of the impact of flow reversal on the dynamics of cascades of reactors. Periodic and chaotic oscillations occur in the analyzed system. There is a dependence between the oscillation period of the state variable of the system without flow reversal and the recurrence period of windows of chaos in the steady-state diagram of the system with flow reversal.

  19. Bott periodicity of inclusions

    CERN Document Server

    Mare, Augustin-Liviu

    2011-01-01

    When looking at Bott's original proof of his periodicity theorem for the stable homotopy groups of the orthogonal and unitary groups, one sees in the background a differential geometric periodicity phenomenon. We show that this geometric phenomenon extends to the standard inclusion of the orthogonal group into the unitary group. This explains the periodicity of the group homomorphisms between stable homotopy groups which are induced by the inclusion map. Standard inclusions between other classical Riemannian symmetric spaces are also discussed.

  20. Painful menstrual periods

    Science.gov (United States)

    Menstruation - painful; Dysmenorrhea; Periods - painful; Cramps - menstrual; Menstrual cramps ... related activities for a few days during each menstrual cycle. Painful menstruation is the leading cause of ...

  1. Hypokalemic periodic paralysis

    National Research Council Canada - National Science Library

    Abbas, Haider; Kothari, Nikhil; Bogra, Jaishri

    2012-01-01

    Hypokalemic periodic paralysis is a rare genetic disorder characterized by recurrent attacks of skeletal muscle weakness with associated hypokalemia which is precipitated by stress, cold, carbohydrate...

  2. Second Period Access Report

    DEFF Research Database (Denmark)

    Maisondieu, Christophe; Giebhardt, Jochen; Tetu, Amelie

    The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive....

  3. The Living Periodic Table

    Science.gov (United States)

    Nahlik, Mary Schrodt

    2005-01-01

    To help make the abstract world of chemistry more concrete eighth-grade students, the author has them create a living periodic table that can be displayed in the classroom or hallway. This display includes information about the elements arranged in the traditional periodic table format, but also includes visual real-world representations of the…

  4. Latent Period of Relaxation.

    Science.gov (United States)

    Kobayashi, M; Irisawa, H

    1961-10-27

    The latent period of relaxation of molluscan myocardium due to anodal current is much longer than that of contraction. Although the rate and the grade of relaxation are intimately related to both the stimulus condition and the muscle tension, the latent period of relaxation remains constant, except when the temperature of the bathing fluid is changed.

  5. On some periodicity effects

    DEFF Research Database (Denmark)

    Sorokin, Sergey V.

    2015-01-01

    The talk is concerned with the modelling of wave propagation in and vibration of periodic elastic structures. Although analysis of wave-guide properties of infinite periodic structures is a well establish research subject, some issues have not yet been fully addressed in the literature. The aim o...

  6. The Living Periodic Table

    Science.gov (United States)

    Nahlik, Mary Schrodt

    2005-01-01

    To help make the abstract world of chemistry more concrete eighth-grade students, the author has them create a living periodic table that can be displayed in the classroom or hallway. This display includes information about the elements arranged in the traditional periodic table format, but also includes visual real-world representations of the…

  7. Periodic Time Series Models

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans); R. Paap (Richard)

    2004-01-01

    textabstractThis book considers periodic time series models for seasonal data, characterized by parameters that differ across the seasons, and focuses on their usefulness for out-of-sample forecasting. Providing an up-to-date survey of the recent developments in periodic time series, the book

  8. Periods and Nori motives

    CERN Document Server

    Huber, Annette

    2017-01-01

    This book casts the theory of periods of algebraic varieties in the natural setting of Madhav Nori’s abelian category of mixed motives. It develops Nori’s approach to mixed motives from scratch, thereby filling an important gap in the literature, and then explains the connection of mixed motives to periods, including a detailed account of the theory of period numbers in the sense of Kontsevich-Zagier and their structural properties. Period numbers are central to number theory and algebraic geometry, and also play an important role in other fields such as mathematical physics. There are long-standing conjectures about their transcendence properties, best understood in the language of cohomology of algebraic varieties or, more generally, motives. Readers of this book will discover that Nori’s unconditional construction of an abelian category of motives (over fields embeddable into the complex numbers) is particularly well suited for this purpose. Notably, Kontsevich's formal period algebra represents a to...

  9. Mean-periodic functions

    Directory of Open Access Journals (Sweden)

    Carlos A. Berenstein

    1980-01-01

    Full Text Available We show that any mean-periodic function f can be represented in terms of exponential-polynomial solutions of the same convolution equation f satisfies, i.e., u∗f=0(μ∈E′(ℝn. This extends to n-variables the work of L. Schwartz on mean-periodicity and also extends L. Ehrenpreis' work on partial differential equations with constant coefficients to arbitrary convolutors. We also answer a number of open questions about mean-periodic functions of one variable. The basic ingredient is our work on interpolation by entire functions in one and several complex variables.

  10. Gas and electric power 2003. Evolution of the energy panorama in Europe: evaluation, forecasting and precautions; Gaz et electricite 2003. Changement du panorama energetique en Europe: bilan, previsions et precautions

    Energy Technology Data Exchange (ETDEWEB)

    Boigegrain, R.; Tran Thiet, J.P.; Givry, L.; Lapierre, A.; Vivies, P. de; Brelle, B.; Vedrenne, Ph.; Didier, E.; Munch, P.; Rodrigues, St.; Lermusieau, Ph.; Macchiati, A.; Lamboley, Ph.; Bouchard, G.; Canetti, J.; Bresson, Th. de; Chevalier, J.M.; Saint Andre, B.; Werquin, A.; Mouton, F.R.; Boulanger, Ph.; Terzian, P

    2003-11-01

    This 12. international congress on gas and electricity covers the following topics: 1 - change in the energy panorama in Europe: statement, forecasting and precautions: fusions, acquisitions, partnerships and their consequences; evolution of the regulation: actors, decisions and time delays (regulation of electricity and gas in Europe - convergencies and divergences; specificities of the French gas and electricity markets and their perspectives of evolution; focus on the 2003 highlights: the January 3, 2003 law, about 20 new decrees and the 2. gas directive); market regulation: new missions, powers and limitations of the different actors (mission, power and place of regulation authorities today and their possible evolution, status competences extension towards gas; consequences of the introduction of the adjustment mechanism, new stakes of power transportation networks; stakes for gas transport and storage in France and in Europe); spot markets and suitable solutions for industrialists (short-term management of risks; juridical and legal precautions to take before starting a power trade activity; short- and medium-term risk management possibilities; 2 - markets opening and new strategies of energy purchase and selling: strategies of foreign actors in France and opportunities for French actors abroad (market opening and its stakes, specificities and opportunities of the energy market in Italy; challenges and opportunities of gas markets opening in Europe: the Ruhrgas approach; stakes of the French market opening: experience feedback of Endesa Europe); repositioning of activities (the new position of Gaz de France (GdF); the deregulated market: risks and opportunities); changing of supplier or partnerships power (towards commercial repositioning); round table: regulators, suppliers, purchasers: are you ready? The congress ends with a practical training course emceed by Endesa: the French electricity and gas markets in the European context; the management of the

  11. Setting the Periodic Table.

    Science.gov (United States)

    Saturnelli, Annette

    1985-01-01

    Examines problems resulting from different forms of the periodic table, indicating that New York State schools use a form reflecting the International Union of Pure and Applied Chemistry's 1984 recommendations. Other formats used and reasons for standardization are discussed. (DH)

  12. The Periodic Table CD.

    Science.gov (United States)

    Banks, Alton J.; Holmes, Jon L.

    1995-01-01

    Describes the characteristics of the digitized version of The Periodic Table Videodisc. Provides details about the organization of information and access to the data via Macintosh and Windows computers. (DDR)

  13. Familial Periodic Paralyses

    Science.gov (United States)

    ... and less severe than the hypokalemic form. Muscle spasms are common. × Definition Familial periodic paralyses are a ... and less severe than the hypokalemic form. Muscle spasms are common. View Full Definition Treatment Treatment of ...

  14. Extremal periodic wave profiles

    Directory of Open Access Journals (Sweden)

    E. van Groesen

    2007-01-01

    Full Text Available As a contribution to deterministic investigations into extreme fluid surface waves, in this paper wave profiles of prescribed period that have maximal crest height will be investigated. As constraints the values of the momentum and energy integrals are used in a simplified description with the KdV model. The result is that at the boundary of the feasible region in the momentum-energy plane, the only possible profiles are the well known cnoidal wave profiles. Inside the feasible region the extremal profiles of maximal crest height are "cornered" cnoidal profiles: cnoidal profiles of larger period, cut-off and periodically continued with the prescribed period so that at the maximal crest height a corner results.

  15. On semi-periods

    CERN Document Server

    Avram, A C; Jancic, D; Uni, H; Uni, Humboldt

    1995-01-01

    The periods of the three-form on a Calabi-Yau manifold are found as solutions of the Picard-Fuchs equations; however, the toric varietal method leads to a generalized hypergeometric system of equations which has more solutions than just the periods. This same extended set of equations can be derived from symmetry considerations. Semi-periods are solutions of this extended system. They are obtained by integration of the three-form over chains; these chains can be used to construct cycles which, when integrated over, give periods. In simple examples we are able to obtain the complete set of solutions for the extended system. We also conjecture that a certain modification of the method will generate the full space of solutions in general.

  16. Setting the Periodic Table.

    Science.gov (United States)

    Saturnelli, Annette

    1985-01-01

    Examines problems resulting from different forms of the periodic table, indicating that New York State schools use a form reflecting the International Union of Pure and Applied Chemistry's 1984 recommendations. Other formats used and reasons for standardization are discussed. (DH)

  17. The Periodic Table CD.

    Science.gov (United States)

    Banks, Alton J.; Holmes, Jon L.

    1995-01-01

    Describes the characteristics of the digitized version of The Periodic Table Videodisc. Provides details about the organization of information and access to the data via Macintosh and Windows computers. (DDR)

  18. Optimal periodic control

    CERN Document Server

    Colonius, Fritz

    1988-01-01

    This research monograph deals with optimal periodic control problems for systems governed by ordinary and functional differential equations of retarded type. Particular attention is given to the problem of local properness, i.e. whether system performance can be improved by introducing periodic motions. Using either Ekeland's Variational Principle or optimization theory in Banach spaces, necessary optimality conditions are proved. In particular, complete proofs of second-order conditions are included and the result is used for various versions of the optimal periodic control problem. Furthermore a scenario for local properness (related to Hopf bifurcation) is drawn up, giving hints as to where to look for optimal periodic solutions. The book provides mathematically rigorous proofs for results which are potentially of importance in chemical engineering and aerospace engineering.

  19. Hyperkalemic periodic paralysis

    Science.gov (United States)

    ... Rott K, Rudel R, Lehmann-Horn F. Muscle channelopathies: myotonias and periodic paralyses. In: Darras BT, Jones ... Elsevier; 2015:chap 38. Kerchner GA, Ptacek LJ. Channelopathies: episodic and electrical disorders of nervous system. In: ...

  20. Hypokalemic periodic paralysis

    Science.gov (United States)

    ... Rott K, Rudel R, Lehmann-Horn F. Muscle channelopathies: myotor and periodic paralyses. In: Darras BT, Jones ... Elsevier; 2015:chap 38. Kerchner GA, Ptacek LJ. Channelopathies. In: Daroff RB, Jankovic J, Mazziotta JC, Pomeroy ...

  1. Historically defined autobiographical periods

    DEFF Research Database (Denmark)

    Brown, Norman R.; Hansen, Tia G. B.; Lee, Peter J.;

    2012-01-01

    The chapter reviews a research programme that has demonstrated the existence of historically defined autobiographical periods and identified the conditions that bring them about. Data from four samples of World War II-generation adults show that historically defined autobiographical periods endure...... over time and theoretical implications are discussed, notably by introducing a new approach to autobiographical memory, Transition Theory, which assumes that autobiographical memory is organized by transitional events that can be selfinitiated or externally imposed - historically defined...

  2. A Comprehensive Numerical Study on Effects of Natural Gas Composition on the Operation of an HCCI Engine Une étude numérique complète sur les effets de la composition du gaz naturel carburant sur le réglage d’un moteur HCCI

    Directory of Open Access Journals (Sweden)

    Jahanian O.

    2011-11-01

    Full Text Available Homogeneous Charge Compression Ignition (HCCI engine is a promising idea to reduce fuel consumption and engine emissions. Natural Gas (NG, usually referred as clean fuel, is an appropriate choice for HCCI engines due to its suitable capability of making homogenous mixture with air. However, varying composition of Natural Gas strongly affects the auto-ignition characteristics of in-cylinder mixture and the performance of the HCCI engine. This paper has focused on the influence of Natural Gas composition on engine operation in HCCI mode. Six different compositions of Natural Gas (including pure methane have been considered to study the engine performance via a thermo-kinetic zero-dimensional model. The simulation code covers the detailed chemical kinetics of Natural Gas combustion, which includes Zeldovich extended mechanism to evaluate NOx emission. Validations have been made using experimental data from other works to ensure the accuracy needed for comparison study. The equivalence ratio and the compression ratio are held constant but the engine speed and mixture initial temperature are changed for comparison study. Results show that the peak value of pressure/temperature of in-cylinder mixture is dependent of fuel Wobbe number. Furthermore, engine gross indicated power is linearly related to fuel Wobbe number. Gross indicated work, gross mean effective pressure, and NOx are the other parameters utilized to compare the performance of engine using different fuel compositions. Le moteur HCCI (Homogeneous Charge Compression Ignition, ou à allumage par compression d’une charge homogène est une idée prometteuse pour réduire la consommation de carburant et les émissions polluantes. Le gaz naturel, considéré généralement comme un carburant propre, est un choix approprié pour les moteurs HCCI en raison de sa capacité à former avec l’air un mélange homogène. Cependant, la composition du gaz naturel influe fortement sur les caract

  3. Treatment for periodic paralysis.

    Science.gov (United States)

    Sansone, V; Meola, G; Links, T P; Panzeri, M; Rose, M R

    2008-01-23

    Primary periodic paralyses are rare inherited muscle diseases characterised by episodes of flaccid weakness affecting one or more limbs, lasting several hours to several days, caused by mutations in skeletal muscle channel genes. The objective of this review was to systematically review treatment of periodic paralyses. We searched the Cochrane Neuromuscular Disease Group Trials Register, MEDLINE (from January 1966 to July 2007), and EMBASE (from January 1980 to July 2007) and any other available international medical library sources from the University of Milan for randomised trials. We included randomised (including cross-over studies) and quasi-randomised trials in participants with primary periodic paralyses, in which any form of treatment, including physical therapy and alternative therapies, was compared to placebo or another treatment. Our primary outcome measure was the change in attack severity or frequency by eight weeks from the start of treatment. Our secondary outcome measures were: change in muscle strength and mass; change in Quality of Life, using Short Form 36 (SF36) or similar; preference of treatment strategy; adverse effects at eight weeks. Three studies met our inclusion criteria. In one study dichlorphenamide (DCP) vs placebo was tested in two groups of participants: 42 with hypokalemic periodic paralysis (HypoPP) and 31 with hyperkalemic periodic paralysis (HyperPP), based on clinical criteria. Thirty-four of 42 participants with hypokalemic periodic paralysis completed both treatment phases. For the 34 participants having attack rate data for both treatment phases, the mean improvement in attack rate (P = 0.02) and severity-weighted attack rate (P = 0.01) on DCP relative to placebo were statistically significant. Fifteen preferred DCP, three placebo and six their baseline medication. Twenty-four of 31 participants with hyperkalemic periodic paralysis completed both treatment phases: for the 16 participants who had attack rate data for both

  4. Periodic Ising Correlations

    CERN Document Server

    Hystad, Grethe

    2010-01-01

    In this paper, we first rework B. Kaufman's 1949 paper, "Crystal Statistics. II. Partition Function Evaluated by Spinor Analysis", by using representation theory. Our approach leads to a simpler and more direct way of deriving the spectrum of the transfer matrix for the finite periodic Ising model. We then determine formulas for the spin correlation functions that depend on the matrix elements of the induced rotation associated with the spin operator in a basis of eigenvectors for the transfer matrix. The representation of the spin matrix elements is obtained by considering the spin operator as an intertwining map. We exhibit the "new" elements V+ and V- in the Bugrij-Lisovyy formula as part of a holomorphic factorization of the periodic and anti-periodic summability kernels on the spectral curve associated with the induced rotation for the transfer matrix.

  5. Thyrotoxic periodic paralysis

    Directory of Open Access Journals (Sweden)

    Rojith Karandode Balakrishnan

    2011-01-01

    Full Text Available This article aims at highlighting the importance of suspecting thyrotoxicosis in cases of recurrent periodic flaccid paralysis; especially in Asian men to facilitate early diagnosis of the former condition. A case report of a 28 year old male patient with recurrent periodic flaccid paralysis has been presented. Hypokalemia secondary to thyrotoxicosis was diagnosed as the cause of the paralysis. The patient was given oral potassium intervention over 24 hours. The patient showed complete recovery after the medical intervention and was discharged after 24 hours with no residual paralysis. Thyrotoxic periodic paralysis (TPP is a complication of thyrotoxicosis, more common amongst males in Asia. It presents as acute flaccid paralysis in a case of hyperthyroidism with associated hypokalemia. The features of thyrotoxicosis may be subtle or absent. Thus, in cases of recurrent or acute flaccid muscle paralysis, it is important to consider thyrotoxicosis as one of the possible causes, and take measures accordingly.

  6. Hyperthyroid hypokalemic periodic paralysis.

    Science.gov (United States)

    Neki, N S

    2016-01-01

    Hyperthyroid periodic paralysis (HPP) is a rare life threatening complication of hyperthyroidism commonly occurring in young Asian males but sporadically found in other races. It is characterised by hypokalemia and acute onset paraparesis with prevalence of one in one hundred thousand (1 in 100000). The symptoms resolve promptly with potassium supplementation. Nonselective beta blockers like propranol can also be used to ameliorate and prevent subsequent paralytic attack. We report a case of 22 year old male presenting with hyperthyroid periodic paralysis (HPP) having very low serum potassium level.

  7. Hereditary periodic fever syndromes

    NARCIS (Netherlands)

    McDermott, MF; Frenkel, J

    Hereditary periodic fever syndromes are defined by recurrent attacks of generalised inflammation for which no infectious or auto-immune cause can be identified. For most of these disorders, the molecular basis has recently been elucidated. This has opened the prospect of novel therapeutic

  8. Periodic Table of Students.

    Science.gov (United States)

    Johnson, Mike

    1998-01-01

    Presents an exercise in which an eighth-grade science teacher decorated the classroom with a periodic table of students. Student photographs were arranged according to similarities into vertical columns. Students were each assigned an atomic number according to their placement in the table. The table is then used to teach students about…

  9. A Modern Periodic Table.

    Science.gov (United States)

    Herrenden-Harker, B. D.

    1997-01-01

    Presents a modern Periodic Table based on the electron distribution in the outermost shell and the order of filling of the sublevels within the shells. Enables a student to read off directly the electronic configuration of the element and the order in which filling occurs. (JRH)

  10. Oscillations following periodic reinforcement.

    Science.gov (United States)

    Monteiro, Tiago; Machado, Armando

    2009-06-01

    Three experiments examined behavior in extinction following periodic reinforcement. During the first phase of Experiment 1, four groups of pigeons were exposed to fixed interval (FI 16s or FI 48s) or variable interval (VI 16s or VI 48s) reinforcement schedules. Next, during the second phase, each session started with reinforcement trials and ended with an extinction segment. Experiment 2 was similar except that the extinction segment was considerably longer. Experiment 3 replaced the FI schedules with a peak procedure, with FI trials interspersed with non-food peak interval (PI) trials that were four times longer. One group of pigeons was exposed to FI 20s PI 80s trials, and another to FI 40s PI 160s trials. Results showed that, during the extinction segment, most pigeons trained with FI schedules, but not with VI schedules, displayed pause-peck oscillations with a period close to, but slightly greater than the FI parameter. These oscillations did not start immediately after the onset of extinction. Comparing the oscillations from Experiments 1 and 2 suggested that the alternation of reconditioning and re-extinction increases the reliability and earlier onset of the oscillations. In Experiment 3 the pigeons exhibited well-defined pause-peck cycles since the onset of extinction. These cycles had periods close to twice the value of the FI and lasted for long intervals of time. We discuss some hypotheses concerning the processes underlying behavioral oscillations following periodic reinforcement.

  11. Periodically poled silicon

    Science.gov (United States)

    Hon, Nick K.; Tsia, Kevin K.; Solli, Daniel R.; Khurgin, Jacob B.; Jalali, Bahram

    2010-02-01

    Bulk centrosymmetric silicon lacks second-order optical nonlinearity χ(2) - a foundational component of nonlinear optics. Here, we propose a new class of photonic device which enables χ(2) as well as quasi-phase matching based on periodic stress fields in silicon - periodically-poled silicon (PePSi). This concept adds the periodic poling capability to silicon photonics, and allows the excellent crystal quality and advanced manufacturing capabilities of silicon to be harnessed for devices based on χ(2)) effects. The concept can also be simply achieved by having periodic arrangement of stressed thin films along a silicon waveguide. As an example of the utility, we present simulations showing that mid-wave infrared radiation can be efficiently generated through difference frequency generation from near-infrared with a conversion efficiency of 50% based on χ(2) values measurements for strained silicon reported in the literature [Jacobson et al. Nature 441, 199 (2006)]. The use of PePSi for frequency conversion can also be extended to terahertz generation. With integrated piezoelectric material, dynamically control of χ(2)nonlinearity in PePSi waveguide may also be achieved. The successful realization of PePSi based devices depends on the strength of the stress induced χ(2) in silicon. Presently, there exists a significant discrepancy in the literature between the theoretical and experimentally measured values. We present a simple theoretical model that produces result consistent with prior theoretical works and use this model to identify possible reasons for this discrepancy.

  12. Treatment for periodic paralysis

    NARCIS (Netherlands)

    Sansone, [No Value; Meola, G.; Links, T. P.; Panzeri, M.; Rose, M. R.

    2008-01-01

    Background Primary periodic paralyses are rare inherited muscle diseases characterised by episodes of flaccid weakness affecting one or more limbs, lasting several hours to several days, caused by mutations in skeletal muscle channel genes. Objectives The objective of this review was to systematical

  13. A Modern Periodic Table.

    Science.gov (United States)

    Herrenden-Harker, B. D.

    1997-01-01

    Presents a modern Periodic Table based on the electron distribution in the outermost shell and the order of filling of the sublevels within the shells. Enables a student to read off directly the electronic configuration of the element and the order in which filling occurs. (JRH)

  14. Periodic Table of Students.

    Science.gov (United States)

    Johnson, Mike

    1998-01-01

    Presents an exercise in which an eighth-grade science teacher decorated the classroom with a periodic table of students. Student photographs were arranged according to similarities into vertical columns. Students were each assigned an atomic number according to their placement in the table. The table is then used to teach students about…

  15. Scheduling: Seven Period Day

    Science.gov (United States)

    Williamson, Ronald

    2010-01-01

    Driven by stable or declining financial resources many school districts are considering the costs and benefits of a seven-period day. While there is limited evidence that any particular scheduling model has a greater impact on student learning than any other, it is clear that the school schedule is a tool that can significantly impact teacher…

  16. Treatment for periodic paralysis

    NARCIS (Netherlands)

    Sansone, [No Value; Meola, G.; Links, T. P.; Panzeri, M.; Rose, M. R.

    2008-01-01

    Background Primary periodic paralyses are rare inherited muscle diseases characterised by episodes of flaccid weakness affecting one or more limbs, lasting several hours to several days, caused by mutations in skeletal muscle channel genes. Objectives The objective of this review was to systematical

  17. Chaotic period doubling

    NARCIS (Netherlands)

    Chandramouli, V. V. M. S.; Martens, M.; De Melo, W.; Tresser, C. P.

    2009-01-01

    The period doubling renormalization operator was introduced by Feigenbaum and by Coullet and Tresser in the 1970s to study the asymptotic small-scale geometry of the attractor of one-dimensional systems that are at the transition from simple to chaotic dynamics. This geometry turns out not to depend

  18. Gas Well Testing Analysis Using Finite-Difference Models and Optimization Techniques Analyse d'essais de puits de gaz par des modèles utilisant la méthode des différences finies et par des techniques d'optimisation

    Directory of Open Access Journals (Sweden)

    Darderes E. A.

    2006-11-01

    Full Text Available In reservoir engineering studies of gas fields, three important parameters are needed: the permeability-thickness product, the skin factor, and the inertial-turbulent factor. Several methods have been proposed to determine these parameters from gas well tests. The most powerful one is the pseudo-steady state analysis, where a linear dependence on a semilogarithmic plot is found between the real gas pseudo-pressure and time. Another one is the type-curve matching. Both have drawbacks because they can be rigorously applied only to specific cases. An automated type-curve match, which provides a general method to analyze well test data, is presented in this paper. It is based on the adjustment of a numerical model to gas well test data, by means of optimization techniques. The numerical model is the solution of the second order strongly non-linear partial differential equation which rules the radial flow of real gases towards a well. The differential equation is solved by finite-differences, taking into account the variation of gas properties with pressure. In order to simulate any gas well test, appropriate initial and boundary conditions are imposed. The least squares method is used to minimize residual differences between actual pressures measured during test and computed pressures. Two optimization techniques are applied to obtain the best estimate of parameters that minimize the sum of the square of the residuals: the univariate method of Fibonacci [1] and the multivariate method of Marquardt [1, 2]. This procedure is applied to a single-rate and a two-rate drawdown test. Numerical results showed excellent agreement with well test data. Les études de gisements de gaz rendent indispensables la connaissance de trois paramètres importants : la capacité de flux (produit de la perméabilité par l'épaisseur de la couche productrice, l'effet de peau et le facteur d'inertie et de turbulence. On connaît plusieurs méthodes pour déterminer ces

  19. Thyrotoxic periodic paralysis

    Energy Technology Data Exchange (ETDEWEB)

    Ferreiro, J.E.; Arguelles, D.J.; Rams, H. Jr.

    1986-01-01

    A case of thyrotoxic periodic paralysis is reported in a Hispanic man with an unusual recurrence six weeks after radioactive iodine treatment. Thyrotoxic periodic paralysis has now been well characterized in the literature: it occurs primarily in Orientals with an overwhelming male preponderance and a higher association of specific HLA antigens. Clinical manifestations include onset after high carbohydrate ingestion or heavy exertion, with progressive symmetric weakness leading to flaccid paralysis of the extremities and other muscle groups, lasting several hours. If hypokalemia is present, potassium administration may help abort the attack. Although propranolol can be efficacious in preventing further episodes, the only definitive treatment is establishing a euthyroid state. The pathophysiology is still controversial, but reflects altered potassium and calcium dynamics as well as certain morphologic characteristics within the muscle unit itself.

  20. Cells anticipate periodic events

    Science.gov (United States)

    Nakagaki, Toshiyuki

    2009-03-01

    We show that an amoeboid organism can anticipate the timing of periodic events. The plasmodium of the true slime mold Physarum polycephalum moves rapidly under favourable conditions, but stops moving when transferred to less-favourable conditions. Plasmodia exposed to unfavourable conditions, presented in three consecutive pulses at constant intervals, reduced their locomotive speed in response to each episode. When subsequently subjected to favourable conditions, the plasmodia spontaneously reduced their locomotive speed at the time point when the next unfavourable episode would have occurred. This implied anticipation of impending environmental change. After this behaviour had been evoked several times, the locomotion of the plasmodia returned to normal; however, the anticipatory response could subsequently be induced by a single unfavourable pulse, implying recall of the memorized periodicity. We explored the mechanisms underlying these behaviours from a dynamical systems perspective. Our results hint at the cellular origins of primitive intelligence and imply that simple dynamics might be sufficient to explain its emergence.

  1. Periodic paralysis: understanding channelopathies.

    Science.gov (United States)

    Lehmann-Horn, Frank; Jurkat-Rott, Karin; Rüdel, Reinhardt

    2002-01-01

    Familial periodic paralyses are typical channelopathies (i.e., caused by functional disturbances of ion channel proteins). The episodes of flaccid muscle weakness observed in these disorders are due to underexcitability of sarcolemma leading to a silent electromyogram and the lack of action potentials even upon electrical stimulation. Interictally, ion channel malfunction is well compensated, so that special exogenous or endogenous triggers are required to produce symptoms in the patients. An especially obvious trigger is the level of serum potassium (K+), the ion responsible for resting membrane potential and degree of excitability. The clinical symptoms can be caused by mutations in genes coding for ion channels that mediate different functions for maintaining the resting potential or propagating the action potential, the basis of excitability. The phenotype is determined by the type of functional defect brought about by the mutations, rather than the channel effected, because the contrary phenotypes hyperkalemic periodic paralysis (HyperPP) and hypokalemic periodic paralysis (HypoPP) may be caused by point mutations in the same gene. Still, the common mechanism for inexcitability in all known episodic-weakness phenotypes is a long-lasting depolarization that inactivates sodium ion (Na+) channels, initiating the action potential.

  2. Akdağ, Özcan. "Gazâlî ve Aquino’lu Thomas’a Göre Tanrı’nın Özgürlüğü". Doktora tezi, Erciyes Üniversitesi Sosyal Bilimler Enstitüsü, Kayseri 2015.

    Directory of Open Access Journals (Sweden)

    Özcan Akdağ

    2016-06-01

    Full Text Available Bu çalışmanın temel amacı, Tanrı’nın fiillerinde özgür olup olmadığı meselesini Gazâlî ve Thomas ekseninde ele almak ve onların iddialarını, haklılık ve iç tutarlılık açısından incelemektir. Bu amaç doğrultusunda Giriş bölümünde soruna dair genel bir bilgi verilmiş ve bu konuda yapılmış çalışmalardan bir kısmı ele alınarak değerlendirilmiştir. Tezin birinci bölümünde, özgürlük kavramından ne anlaşıldığı, determinizmle ilişkisi, Tanrı’nın özgürlüğü sorununun ontolojik ve semantik boyutu ele alınmış ve meselenin tarihsel süreçte nasıl algılandığı tasvir edilmiştir. Çalışmanın ikinci bölümünde, Thomas’ın Gazâlî’nin fikirlerinden nasıl ve ne şekilde etkilendiği ortaya konulduktan sonra her iki düşünürün uluhiyet anlayışı ele alınmış, bu bağlamda onların benzeştikleri ve ayrıştıkları noktalar tespit edilmiştir. Üçüncü bölümde ise, Gazâlî ve Thomas’ın Tanrı-Âlem ilişkisine dair görüşlerine yer verilmiş ve Tanrı’nın özgürlüğünün tezahürü olarak değerlendirilebileceğini düşündüğümüz yaratma, mucize, ahlakî değerlerin ilahî emirlerle ilişkisi gibi konular ele alınmıştır.

  3. Natural Gas Hydrate Phase Equilibria and Kinetics : Understanding the State-Of-The-Art Équilibres des phases des hydrates de gaz naturel et cinétique

    Directory of Open Access Journals (Sweden)

    Sloan E. D.

    2006-11-01

    Full Text Available An overview is given of gas hydrate phase equilibria and kinetics. It is suggested that with only a few exceptions hydrate phase equilibrium conditions may be predicted with acceptable accuracy for industrial purposes via the current state-of-the art. Hydrate research is at a milestone, going beyond equilibrium experiments to time-dependent measurements, such as in the kinetic arena, where there is a severe paucity of date. To illustrate the concepts, two qualitative microscopic models are presented :1 the hydrate guest: cavity size ratio and2 the dissolution of apolar molecules in liquid water. Hypotheses for macroscopic phase equilibria and kinetic nucleation phenomena are given, based upon the two models. Cet article présente brièvement les équilibres des phases des hydrates de gaz naturel et leur cinétique. Il signale qu'en l'état actuel des connaissances, les conditions d'équilibre des phases des hydrates peuvent être connues, à quelques exceptions près, avec une précision acceptable dans un but industriel. La recherche sur les hydrates atteint un point décisif, elle dépasse les expériences d'équilibre et s'intéresse aux mesures variant en fonction du temps, celles de la cinétique par exemple, où les données sont particulièrement rares. Pour illustrer le concept deux modèles qualitatifs microscopiques sont présentés : 1 le rapport de grosseur hydrate hôte/cavité, et 2 la dissolution des molécules apolaires dans l'eau liquide. L'auteur émet des hypothèses relatives aux phénomènes macroscopiques d'équilibres des phases et de nucléation cinétique, basées sur ces deux modèles.

  4. Contrôle et prévention des émissions de SO² à l'usine de traitement de gaz naturel de Lacq SO² Emission Control and Prevention At the Lacq Natural Gas Processing Plant

    Directory of Open Access Journals (Sweden)

    Bonometti G.

    2006-11-01

    Full Text Available Le gisement de gaz naturel de Lacq, mis en production à partir de 1958 dans le Sud-Ouest de la France, est aujourd'hui exploité avec les gisements satellites de Meillon, Saint-Faust, Pont-d'As à un régime journalier de près de 33 millions de mètres cubes. La forte proportion d'hydrogène sulfuré qu'ils contiennent entraîne une production de plus de 5500 tonnes par jour de soufre. La concentration sur un même site d'une source potentielle aussi importante d'anhydride sulfureux pouvait laisser craindre un impact d'autant plus grave sur l'environnement que les conditions météorologiques locales étaient généralement défavorables. Les systèmes de contrôle et de prévention étudiés, développés et exploités à l'usine de Lacq par la Société Nationale Elf Aquitaine (Production SNEA (P, au fur et a mesure du développement des champs, sont présentés en même temps que les résultats obtenus. De nombreuses actions lancées simultanément ont apporté leur contribution particulière à la résolution du problème posé. The Lacq natural gas field, which has been producing since 1958 in Southwest France, is currently producing, together with thé satellite fields of Meillon, Saint-Faust and Pont-d'As, of a daily rate of nearly 33 million cubic meters. The high proportion of hydrogen sulfide they contain results in a daily production of more than 5,500 tonnes of sulfur. The concentration of such a large potentiel source of sulfur dioxide in one place might be considered as a serious threat to thé environment because local weather conditions are very often unfavorable. The control and prévention systems researched, developed and operated at the Lacq plant by Société Nationale Elf Aquitaine (Production SNEA (PI as the gas fields have been developed are described together with the results obtained. Various measures token simultaneously have collectively helped ta overcome the problem.

  5. The postanesthetic period. Complications.

    Science.gov (United States)

    Malamed, S F

    1987-01-01

    Postanesthetic complications can occur even in the best of circumstances. Proper preparation of the staff, aggressive monitoring of the recovering patient, and early recognition and management of the complications are essential if the outcome is to be successful. In reviewing postanesthetic complications, two factors are present in the overwhelming majority of situations--hypoxia and hypercarbia--often the direct result of inadequate monitoring during the postanesthetic period. The anesthetic procedure is not over once the anesthetic agents are discontinued. The skillful anesthetist is aware of the possibilities of postoperative complications and prevents problems by employing enhanced monitoring techniques during the recovery phase.

  6. Periodic Mesoporous Organosilica Nanorice

    Directory of Open Access Journals (Sweden)

    Mohanty Paritosh

    2008-01-01

    Full Text Available Abstract A periodic mesoporous organosilica (PMO with nanorice morphology was successfully synthesized by a template assisted sol–gel method using a chain-type precursor. The PMO is composed of D and T sites in the ratio 1:2. The obtained mesoporous nanorice has a surface area of 753 m2 g−1, one-dimensional channels, and a narrow pore size distribution centered at 4.3 nm. The nanorice particles have a length of ca. 600 nm and width of ca. 200 nm.

  7. Periods of Hecke characters

    CERN Document Server

    Schappacher, Norbert

    1988-01-01

    The starting point of this Lecture Notes volume is Deligne's theorem about absolute Hodge cycles on abelian varieties. Its applications to the theory of motives with complex multiplication are systematically reviewed. In particular, algebraic relations between values of the gamma function, the so-called formula of Chowla and Selberg and its generalization and Shimura's monomial relations among periods of CM abelian varieties are all presented in a unified way, namely as the analytic reflections of arithmetic identities beetween Hecke characters, with gamma values corresponding to Jacobi sums. The last chapter contains a special case in which Deligne's theorem does not apply.

  8. Periodic truss structures

    Science.gov (United States)

    Zok, Frank W.; Latture, Ryan M.; Begley, Matthew R.

    2016-11-01

    Despite the recognition of the enormous potential of periodic trusses for use in a broad range of technologies, there are no widely-accepted descriptors of their structure. The terminology has been based loosely either on geometry of polyhedra or of point lattices: neither of which, on its own, has an appropriate structure to fully define periodic trusses. The present article lays out a system for classification of truss structure types. The system employs concepts from crystallography and geometry to describe nodal locations and connectivity of struts. Through a series of illustrative examples of progressively increasing complexity, a rational taxonomy of truss structure is developed. Its conceptual evolution begins with elementary cubic trusses, increasing in complexity with non-cubic and compound trusses as well as supertrusses, and, finally, with complex trusses. The conventions and terminology adopted to define truss structure yield concise yet unambiguous descriptions of structure types and of specific (finite) trusses. The utility of the taxonomy is demonstrated by bringing into alignment a disparate set of ad hoc and incomplete truss designations previously employed in a broad range of science and engineering fields. Additionally, the merits of a particular compound truss (comprising two interpenetrating elementary trusses) is shown to be superior to the octet truss for applications requiring high stiffness and elastic isotropy. By systematically stepping through and analyzing the finite number of structure types identified through the present classification system, optimal structures for prescribed mechanical and functional requirements are expected to be ascertained in an expeditious manner.

  9. Un nouveau moyen de mesure absolue du taux gazeux des mélanges gaz-liquides : le SMAC A New Absolute Measurement of the Volumetric Gas Ratio of Gas-Liquid Mixture: the Smac

    Directory of Open Access Journals (Sweden)

    Porot P.

    2006-11-01

    Full Text Available Du graphe (P, V de la compression d'un mélange gaz-liquide, on peut tirer la valeur du taux volumique de gaz dans le mélange. La vérification théorique et expérimentale de ce principe ainsi que ses limites d'application comme moyen de mesure sont présentées. Ce résultat a été utilisé pour développer un système de mesure de l'aération de l'huile moteur, le SMAC (Système de Mesure d'Aération par Compressibilité. Des exemples d'application, tels que l'étude de la sensibilité de certaines huiles à l'aération, sont exposés. Oil aeration can be a real problem in engine oil circuit. The involved lubrication power decrease and thermic properties changes can damage the engine. Furthermore, the increased compressibility is very dangerous for hydraulic systems like valve lash adjusters. A first step to control this aeration is to be able to measure it. Gammametry is often used but this measurement needs a very precise calibration and is quite complicated and dangerous. A new absolute measurement has been discovered, based on the difference of compressibility between air and oil. It is absolute because the measurement principle is independant of the conditions, The system does not need a new calibration at each new environment. It is valid for any gas-liquid mixture. From the (P, V graph of a gas-liquid mixture compression, one can derive the gas-liquid volumetric ratio. The log-log graph (P/PO, 1-V/VO of a mixture sample pressurization always shows an inflexion point. The y value of this inflexion point (1-V/VO is equal to the volumetric gas ratio of the sample (before compression. This phenomenon is obvious on hydraulic curves (see Annexe 1. To check it, we have proceeded to a theoretical demonstration and an experimental verification. The theoretical demonstration of this principle concludes that the principle is verified as long as the ration P index 0 / alpha B is small. B is the oil bulk modulus, alpha is the volumetric gas ratio

  10. Some economic aspects of natural uranium graphite gas reactor types. Present status and trends of costs in France; Quelques aspects economiques de la filiere uranium naturel - Graphite - gaz. Etat actuel et tendance des couts en France

    Energy Technology Data Exchange (ETDEWEB)

    Gaussens, J.; Tanguy, P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Leo, B. [Electricite de France (EDF), 75 - Paris (France)

    1964-07-01

    reduction in investment costs can be obtained without relying on fuel enrichment, and that this development is accompanied moreover by improvements in the operational safety of the reactor. The economic aspects of the main technical problems entailed by these developments are discussed: loading and unloading machines, blowers etc... (authors) [French] Dans une premiere partie, on situe l'interet economique de l'utilisation de l'uranium naturel comme combustible. Cet interet reside a la fois dans le nombre limite et la simplicite relative des operations de mise en forme des elements combustibles, dans le faible cout du produit fini par kwh et dans les immobilisations modestes en capital qu'implique ce cycle par rapport ou cycle de l'uranium enrichi. Tous ces elements permettent de reduire le caractere aleatoire des evaluations des couts, particulierement marque dans le cas de l'uranium enrichi, en raison de la complexite de son cycle et des incertitudes concernant le prix du plutonium. Enfin, la diversite des sources d'approvisionnement en concentre d'uranium naturel opposee au quasi monopole actuel de la separation isotopique, et le faible cout du stockage de ce concentre, offrent des garanties en matiere de securite d'approvisionnement et d'independance economique et politique appreciables par rapport a l'uranium enrichi. En ce qui concerne l'ensemble des capitaux immobilises, on montre que si le cout des centrales au graphite-gaz est plus eleve que celui des centrales eau legere pour certaines gammes de puissance, ce resultat est fortement nuance des que l'on fait intervenir dans un souci d'independance nationale le cout de l'equipement de production des combustibles de l'une et l'autre filiere. Enfin, le cout marginal de la puissance du reacteur au graphite est faible, ses limitations technologiques ont considerablement recule (grace en particulier a l'utilisation du beton

  11. When Periodicities Enforce Aperiodicity

    Science.gov (United States)

    Bédaride, Nicolas; Fernique, Thomas

    2015-05-01

    Non-periodic tilings and local rules are commonly used to model the long range aperiodic order of quasicrystals and the finite-range energetic interactions that stabilize them. This paper focuses on planar rhombus tilings, which are tilings of the Euclidean plane, which can be seen as an approximation of a real plane embedded in a higher dimensional space. Our main result is a characterization of the existence of local rules for such tilings when the embedding space is four-dimensional. The proof is an interplay of algebra and geometry that makes use of the rational dependencies between the coordinates of the embedded plane. We also apply this result to some cases in a higher dimensional embedding space, notably tilings with n-fold rotational symmetry.

  12. Periods and Superstring Amplitudes

    CERN Document Server

    Stieberger, S

    2016-01-01

    Scattering amplitudes which describe the interaction of physical states play an important role in determining physical observables. In string theory the physical states are given by vibrations of open and closed strings and their interactions are described (at the leading order in perturbation theory) by a world-sheet given by the topology of a disk or sphere, respectively. Formally, for scattering of N strings this leads to N-3-dimensional iterated real integrals along the compactified real axis or N-3-dimensional complex sphere integrals, respectively. As a consequence the physical observables are described by periods on M_{0,N} - the moduli space of Riemann spheres of N ordered marked points. The mathematical structure of these string amplitudes share many recent advances in arithmetic algebraic geometry and number theory like multiple zeta values, single-valued multiple zeta values, Drinfeld, Deligne associators, Hopf algebra and Lie algebra structures related to Grothendiecks Galois theory. We review the...

  13. Law no. 2004-803 from August 9, 2004 relative to electricity and gas public utilities and to the power and gas companies; Loi no. 2004-803 du 9 aout 2004 relative au service public de l'electricite et du gaz et aux entreprises electriques et gazieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-09-01

    The aim of this law is to allow the administrations to avoid to use their eligibility right with the opening of the electricity and gas markets to competition. It changes the juridical status of the two public utilities Electricite de France (EdF) and Gaz de France (GdF) into two anonymous companies and creates two additional companies for the management of the power and gas networks. It ensures also the transposition of the European directives from June 26, 2003 (2003/54/CE and 2003/55/CE). It contains some proper dispositions and modifies various existing French laws, in particular the law no. 46-628 from April 8, 1946 about the electricity and gas nationalization and the law no. 2000-108 from February 10, 2000 relative to the modernization and development of the electric public utility. (J.S.)

  14. [Childhood periodic syndromes].

    Science.gov (United States)

    Cuvellier, J-C; Lépine, A

    2010-01-01

    This review focuses on the so-called "periodic syndromes of childhood that are precursors to migraine", as included in the Second Edition of the International Classification of Headache Disorders. Three periodic syndromes of childhood are included in the Second Edition of the International Classification of Headache Disorders: abdominal migraine, cyclic vomiting syndrome and benign paroxysmal vertigo, and a fourth, benign paroxysmal torticollis is presented in the Appendix. The key clinical features of this group of disorders are the episodic pattern and intervals of complete health. Episodes of benign paroxysmal torticollis begin between 2 and 8 months of age. Attacks are characterized by an abnormal inclination and/or rotation of the head to one side, due to cervical dystonia. They usually resolve by 5 years. Benign paroxysmal vertigo presents as sudden attacks of vertigo, accompanied by inability to stand without support, and lasting seconds to minutes. Age at onset is between 2 and 4 years, and the symptoms disappear by the age of 5. Cyclic vomiting syndrome is characterized in young infants and children by repeated stereotyped episodes of pernicious vomiting, at times to the point of dehydration, and impacting quality of life. Mean age of onset is 5 years. Abdominal migraine remains a controversial issue and presents in childhood with repeated stereotyped episodes of unexplained abdominal pain, nausea and vomiting occurring in the absence of headache. Mean age of onset is 7 years. Both cyclic vomiting syndrome and abdominal migraine are noted for the absence of pathognomonic clinical features but also for the large number of other conditions to be considered in their differential diagnoses. Diagnostic criteria, such as those of the Second Edition of the International Classification of Headache Disorders and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition, have made diagnostic approach and management easier. Their diagnosis

  15. Preliminary report on inventory of greenhouse gases. Phase 1; Rapport preliminaire sur l`inventaire de gaz a effet de serre. Phase 1

    Energy Technology Data Exchange (ETDEWEB)

    Fenhann, J.

    1997-07-01

    The United Nations Framework Convention on Climate Change (UNFCC) requires the signatory countries to develop, periodically update, publish and make available to the Conference of the Parties national inventories of anthropogenic greenhouse gas emissions (GHG) by sources and removals by sinks, using comparable methodologies as well as to formulate policies and programmes to adapt to or mitigate climate change. Following the entree-into-force of the Convention, the Government of Burkina Faso requested the Danish Government to provide technical assistance and support in order to assess national contributions to global GHG accumulation and to identify the most relevant GHG mitigation and adaptation options for national target-setting and action. This report presents the results of the Phase 1 of the project. The report summarises: (i) the national inventory on GHG emissions and sinks; (ii) a preliminary forecast of GHG emissions and possible mitigation options, and (iii) a first attempt to analyse the vulnerability and possible adaptation strategies to climate change. (LN) 51 refs.

  16. Natural gas: clearly part of the solution to global climate change; Gaz naturel: un element de la solution au changement de climat de la planete

    Energy Technology Data Exchange (ETDEWEB)

    Soper, W. [Westcoast Energy Inc. (Canada)

    2000-07-01

    While scientific data may be incomplete, there remains little doubt that much of the negative impact on the global climate arises from our use of fossil fuels. Equally there seems little reason to believe that our reliance on fossil fuels will diminish over the short term. World demand for energy continues to grow and alternatives to fossil fuels, such as solar, have yet to assume their full rote. For example, OECD studies released late in 1999 note that renewable account for only two percent of electricity generation in developed countries, while fossil fuels continue to account for some 60 percent. Conservation holds promise but all too often gains are offset by shifting consumer preferences: the widespread popularity of sports utility vehicles and light trucks in North America is playing havoc with the automotive industry's fuel efficiency gains of recent years. For corporations, for governments and for the public at large, the challenge remains to find solutions that are both possible and practical for a problem that has no single cure, nor a certain outcome. But during the transition period to new energy sources, natural gas is destined to play a leading role, as the least carbon intensive of the fossil fuels. (author)

  17. Thermodynamic considerations on a boil-off gas recovery system; Considerations thermo-dynamiques sur le systeme de recuperation du gaz d'evaporation (boil-off)

    Energy Technology Data Exchange (ETDEWEB)

    Lanzi, D.; Vareschi, G. [SNAM S.p.A. (Italy); Sguera, O. [Snamprogetti S.p.A. (Italy)

    2000-07-01

    The Panigaglia LNG re-gasification terminal is equipped with a system recovering the boil-off gas produced during both the unloading and the re-gasification phases. The system consists of a compression station and an absorption column that condenses the boil-off by means of two packing bodies, made of INTALOX METAL ring-type, DN 1'' or 2'', depending on the quantity of boil-off available. The above configuration, which was built during the 1991 terminal revamping, was designed to optimise the previous plant facilities and compression works by compressing the boil-off up to 30 bar. At present, to reduce the operating costs deriving from the electric power consumption due to compression of the gas to high pressures, the possibility of running the column at a pressure less than 25 bar has been evaluated. A new processing solution has been studied. This configuration permits using the LNG coming from the low-pressure pumps and therefore an LNG temperature of 15 deg. C less than the one used in the original system. The maximum boil-off rate that can be absorbed has been calculated at different operating pressures. The thermodynamic (material and energy balance) behaviour of the column has been checked and the thermodynamic studies and statistical analysis have given satisfactory and consistent results. In parallel, the operating parameters referred to a period of about one year, during both the unloading and the operating phases, have been identified and analysed. (authors)

  18. Theory and Practice of a New Class of Equipment for Separation of Particulates from Gases: the Turbulent Flow Precipitator Le précipitateur turbulent : un nouveau type de dispositif de séparation de particules présentes dans un courant de gaz. Théorie et technologie

    Directory of Open Access Journals (Sweden)

    Dullien F. A. L.

    2006-12-01

    Full Text Available The main classes of separators of particulates from gases comprise inertial separators, filters, (wet scrubbers and electrostatic precipitators, each of which technique has its proper niche and each has its advantages and its disadvantages. In the present paper a new class of equipment, the turbulent flow precipitator (TFP for gas cleaning is described that, though at the present only in its infancy, is rapidly gaining popularity because it has some advantages over each and every known type of separator and it has very few limitations. TFPs are far more efficient for the removal of fine particles than inertial separators, unlike filters they do not plug up, they do not present secondary disposal problems and they require less maintenance (and are less expensive than electrostatic precipitators. They can be very efficient also in the submicron range of particle size and there are no practical limitations as far as high temperatures and/or corrosive atmospheres are concerned. They are equally suitable for the removal of solid and liquid particles from gases. Turbulent flow precipitators work on the principle of turbulent eddy penetration into deep regions where there is no net flow, where the eddies die out and where the fine particulates carried by the eddies deposit on collector surfaces. TFPs comprise two well defined regions:- straight, uniform and unobstructed flow passages in which the gas carrying the suspended fine particulates is passed in turbulent flow;- and adjacent collection regions where there is no net gas flow and where all of the separation of particles from the gas takes place. Hence, a TFP is a filter in which the separation of the particulates from the gas takes place outside the passages where the gas flows. Les principaux séparateurs de particules dans un courant de gaz existants sur le marché sont les séparateurs par inertie, les filtres, les laveurs et les électrofiltres. Chaque type de séparateur est destiné à une

  19. Etude d'un procédé d'hydroliquéfaction du charbon pour la production simultanée de gaz et de carburant . . . . . Studies of a Coal Hydrogenation Process to Produce CO-Currently Gas and Gasoline

    Directory of Open Access Journals (Sweden)

    Franckowiak S.

    2006-11-01

    Full Text Available Un des principaux moyens de réintroduire le charbon dans le marché énergétique français est de le transformer en produits utiles comme le gaz de réseau ou les carburants. Les procédés d'oxyvapogazéification permettent d'obtenir un gaz de synthèse qui peut être ensuite converti en gaz riche ou en produits liquides. L'hydrogénation en phase liquide (ou hydroliquéfaction se présente pour le long terme comme une seconde voie qui offre des avantages spécifiques - taux de conversion du charbon et rendement élevés, - production directe de gaz de substitution (GNS et de carburant, - possibilité d'utilisation d'hydrogène provenant de l'électricité nucléaire. Un programme d'étude a été lancé avec la participation du Gaz de France (GDF, du Centre d'études et de recherches des Charbonnages de France (Cerchar, de l'institut Français du Pétrole (lFP et du Centre National de la Recherche Scientifique (CNRS dans le cadre du Groupe d'Étude de la Conversion du Charbon par Hydrogénation (GECH. Un banc d'essai d'hydroliquéfaction situé au Cerchar, d'un débit de 10 kg/h de mélange charbon-solvant, permet d'obtenir des hydrogénats dans des conditions variées et en présence de divers catalyseurs. L'étude de la valorisation de ces hydrogénats est effectuée dans les laboratoires de l'lFP. Les essais et les études effectués permettent d'envisager la production à volonté du GNS, de carburants ou des deux ensemble. Un modèle d'optimisation a été réalisé au GDF pour étudier et comparer les différentes filières en prenant en compte l'utilisation d'hydrogène d'électrolyse ou d'hydrogène produit sur place à partir du résidu de liquéfaction. One of the main ways to bring coal in the future french energy market is to transform it into valuable products. The oxygen steam gasification processes give a synthesis gas which can be converted into SNG or gasoline in a catalytic stage. The liquid phase hydrogenation process is a

  20. Contraction et filamentation des decharges micro-ondes entretenues a la pression atmospherique: Application a la detoxication des gaz a effet de serre

    Science.gov (United States)

    Kabouzi, Yassine

    The remediation of greenhouse gases, such as perfluorinated compounds (PFCs), constitutes a major environmental concern. Plasmas operating at atmospheric pressure offer an efficient technology for the control of toxic and greenhouse gas emission. The two main objectives of the thesis were to investigate the mechanisms of contraction and filamentation in atmospheric-pressure microwave discharges, and to examine their influence on the plasma abatement process of PFC gases in these discharges. The finite thermal conductivity of the gas discharge is responsible for the gas nonuniform heating leading to a contracted discharge column. The gas thermal conductivity and the penetration depth of the microwave electric field in the plasma are shown to set the value of the plasma radius. The degree of contraction and filamentation of microwave discharges can be controlled, and even reduced, by modulating adequately the incident microwave power. The relaxation times of heat conduction and heat release are actually observed to be of the same magnitude, and correspond to the modulation period for which the discharge shows less contraction. PFC molecules are eliminated through their fragmentation by inelastic collisions with electrons and the subsequent oxidation of these fragments. Reformation of PFC molecules is the main process limiting the abatement efficiency in atmospheric-pressure microwave discharges. As a result of discharge radial contraction, a relative "colder" space between the plasma filament and the discharge tube wall favors PFC reformation and, therefore, lowers the destruction efficiency. The PFC destruction efficiency is found to increase with absorbed microwave power. Surface-wave microwave discharges sustained at atmospheric pressure prove to be an efficient and ecological solution for emission reduction of greenhouse gases.

  1. Low intensity natural gas infrared in sports centres; L'infrarouge a basse intensite au gaz naturel dans les centres sportifs

    Energy Technology Data Exchange (ETDEWEB)

    Lajoie, S. [Gaz Metropolitain, Montreal, PQ (Canada)

    2002-09-30

    Infrared devices are being employed more and more for heating buildings. They were traditionally used to heat large spaces higher than 3 metres, such as aviation hangars and industrial buildings. Natural gas infrared devices have found other applications, namely in sports centres, due in large part to the energy efficiency and the resulting comfort. There are three types of infrared devices: low intensity or low intensity tubes, high intensity, and catalytic infrared. Each type of device possesses specific characteristics and applications. For example, infrared tubes are used to uniformly heat a specific area. High intensity devices possess a more intense heat and concentrated in a confined space. Catalytic devices do not have flames, and they can be used in industrial drying processes and thermoforming. In the case of skating rinks, the use of low intensity natural gas infrared tubes is ideal. They reduce the crossed effects of ice cooling load and the spectators need for heat. This is due to infrared acting more on mass (spectators and bleachers) than ambient air. The author described the situation at the Val d'Or arena, Quebec where an energy saving project was initiated two years ago, involving the installation for one of the ice surfaces, of movement sensors to turn off infrared tubes when the rink is unoccupied. The payback period for such equipment is short. The case of the Soccerplex at Lachine, part of the larger City of Montreal, was also discussed. This sports centre comprises indoor soccer fields with 30 foot-high ceilings and large area covering 66,000 square feet (3 soccer fields). Once again, low intensity natural gas infrared tubes were installed and have proved successful.

  2. Near periodicity in dynamical systems

    Institute of Scientific and Technical Information of China (English)

    陈文成

    1995-01-01

    The notion of near periodicity is shown to be equivalent to that of weak near periodicity in dynamical systems. A sufficient condition for the positive near periodicity of a point in dynamical systems is given. The structure of nearly periodic dynamical systems is discussed, and a condition is proved to be necessary and sufficient for a dynamical system on a local compact space to be positively nearly periodic.

  3. Periodicity-dependent stiffness of periodic hydrophilic-hydrophobic heteropolymers

    Science.gov (United States)

    Chowdhury, Debashish; Stauffer, Dietrich; Strey, Reinhard

    1999-08-01

    From extensive Monte Carlo simulations of a Larson model of perfectly periodic heteropolymers (PHP) in water, a striking stiffening is observed as the period of the alternating hydrophobic and hydrophilic blocks is shortened. At short period and low temperature needlelike conformations are the stable conformations. As temperature is increased thermal fluctuations induce kinks and bends. At large periods compact oligomeric globules are observed. From the generalized Larson prescription, originally developed for modeling surfactant molecules in aqueous solutions, we find that the shorter the period is the more stretched the PHP is. This novel effect is expected to stimulate polymer synthesis and trigger research on the rheology of aqueous periodic heteropolymer solutions.

  4. THE WAVELET TRANSFORM OF PERIODIC FUNCTION AND NONSTATIONARY PERIODIC FUNCTION

    Institute of Scientific and Technical Information of China (English)

    刘海峰; 周炜星; 王辅臣; 龚欣; 于遵宏

    2002-01-01

    Some properties of the wavelet transform of trigonometric function, periodic function and nonstationary periodic function have been investigated. The results show that the peak height and width in wavelet energy spectrum of a periodic function are in proportion to its period. At the same time, a new equation, which can truly reconstruct a trigonometric function with only one scale wavelet coefficient, is presented. The reconstructed wave shape of a periodic function with the equation is better than any term of its Fourier series. And the reconstructed wave shape of a class of nonstationary periodic function with this equation agrees well with the function.

  5. Persistence in periodic and almost periodic Lotka-Volterra systems.

    Science.gov (United States)

    Gopalsamy, K

    1984-01-01

    It is shown that a strongly self-regulating (or resource limited) Lotka-Volterra population system can "persist" in a periodic or almost periodic environment if and only if the system tracks the environmental variations.

  6. Performance of natural gas distribution networks during the Kocaeli earthquake - 17 august 1999; Comportement des reseaux de distributions de gaz naturel lors du tremblement de terre de Kocaeli 17 aout 1999

    Energy Technology Data Exchange (ETDEWEB)

    Zarea, M.; Adrien, M. [Gaz de France (GDF), 75 - Paris (France)

    2000-07-01

    The Kocaeli (Izmit) earthquake struck recently, on August 17, 1999, a well developed area of Turkey. This earthquake, of a magnitude 7.4 on the open Richter scale, severely damaged numerous buildings, industrial infrastructure, and made a lot of victims. In this context, most attention is given to issues like: seismology (why and how did it happen, what will happen next, etc.), seismic design and construction (why buildings collapsed and how to avoid this in the future). Some other subjects get less attention, because their direct influence in the overall damage is smaller. The behaviour of 'lifelines', designating all the networks which contribute to 'modern' lifestyle: water, energy, communications, etc., belong to this category. Nevertheless, the performance of lifelines during such strong earthquakes is also important, because they can contribute to minimise its impact. This impact has its usual two aspects: integrity and operability. For instance, the integrity requirement means that failures of the considered lifeline due to the earthquake should not directly affect property and life. The operability requirement means that a given subset of the lifeline remains operational, in order to fulfill vital tasks. We propose here a brief analysis of the performance of two relatively recently commissioned gas distribution systems: IZGAZ in Izmit, close the epicenter, and IDGAS in Istanbul. They have the advantage of representing a large sample of a recent implementation of the PE (polyethylene) technique, which has reached maturity. Both are cases of the Gaz de France 4 bar PE technology transferred to a Turkish operator, who completely managed the crisis. The first part describes the two networks, both their high medium pressure steel network, regulators, and the intermediate PE network, finishing with service lines and boxes. Then, the damage reported by the operational teams and their very important shut-down and blowdown actions are summarised

  7. Apport de la géostatistique à la description des stockages de gaz en aquifère Contribution of Geostatistics to Describing Aquifer Gas-Storage Reservoirs

    Directory of Open Access Journals (Sweden)

    Delhomme J. P.

    2006-11-01

    Full Text Available L'étude du comportement d'un réservoir de gaz en nappe aquifère réclame une connaissance aussi précise que possible des caractéristiques géométriques et pétrophysiques des couches réservoirs. Les moyens d'investigation sont de deux natures : - forages permettant une connaissance locale des roches réservoirs ; - mesures sismiques conduisant à une estimation approximative des cotes de certains repères stratigraphiques, en des points situés le long de profils. Les données recueillies sont donc, par nature, fragmentaires et discrètes : là où elles sont absentes, il y a lieu d'estimer les grandeurs étudiées en tenant compte au mieux de notre connaissance de leur variabilité spatiale. Ce problème d'interpolation optimale a donné lieu, depuis une vingtaine d'années, à l'élaboration et la mise en pratique d'un outil théorique particulièrement bien adapté aux besoins exprimés par les techniciens des sciences de la terre : la théorie des variables régionalisées due à G. Matheron. Des programmes informatiques mettant en oeuvre cette théorie sont actuellement opérationnels. Des exemples d'application en sont donnés : - tracé automatique de cartes structurales à partir des données de forages et des mesures sismiques ; - estimation des incertitudes de prévision sur les profondeurs ; - tracé de plusieurs variantes de carte compatibles avec les données ; - établissement d'éléments statistiques relatifs à une grandeur caractéristique d'un stockage : volume stockable par exemple ; - génération automatique des données nécessaires à la mise en oeuvre d'un modèle maillé de réservoir. Predicting and monitoring the behavior of an aquifer gas-storage reservoir requires as precise a knowledge as possible of the geometric and petrophysical properties of the reservoir layer. Two ways of obtaining this information can be given: (a Boreholes which provide local knowledge of the reservoir, and (b Seismic measurements

  8. Photolysis of Periodate and Periodic Acid in Aqueous Solution

    DEFF Research Database (Denmark)

    Sehested, Knud; Kläning, U. K.

    1978-01-01

    The photochemistry of periodate and periodic acid in aqueous solution was studied (i) by quantum yield measurements at low light intensity (ii) by flash photolysis, and (iii) by photolysis of glassy samples at 77 K. The photochemical studies were supplemented with pulse radiolysis studies...... of aqueous periodate solutions and with kinetic studies using stopped-flow technique. In strongly alkaline solution the photodecomposition of periodate proceeds via formation of O– and IVI. At pH

  9. Single Pellet String Reactor for Intensification of Catalyst Testing in Gas/Liquid/Solid Configuration Réacteur catalytique de type “filaire” pour l’intensification de tests catalytiques en configuration gaz/liquide/solide

    Directory of Open Access Journals (Sweden)

    Hipolito A.I.

    2010-09-01

    . Ce probleme est particulierement critique pour les reactions rapides et tres exothermiques. Une nouvelle geometrie de reacteur est proposee pour intensifier les transferts de matieres autour des grains de catalyseur et accelerer les vitesses superficielles des fluides : le “reacteur filaire”. Pour caracteriser cette nouvelle geometrie de reacteur, une etude hydrodynamique a ete menee avec un reacteur filaire horizontal de section carree de 4,0 × 4,0 mm2 rempli de particules spheriques de diametre compris entre 2 et 4 mm et simulant des grains de catalyseur. Les regimes d’ecoulement ontete etudies a partir d’analyses d’images, des mesures de perte de pression et de distribution de temps de sejour qui ont ete effectuees en ecoulement monophasique liquide et diphasique gaz/liquide. Deux principaux regimes d’ecoulements ont ete observes: un regime de “bulles isolees” et un regime de type “stratifie”. Les retentions liquides sont toujours superieures a 60 %, ce qui indique en complement d’observations visuelles que le catalyseur est toujours correctement irrigue par l’ecoulement liquide. En ecoulement diphasique gaz/liquide, l’ecoulement est de type piston puisque les nombres de Peclet sont toujours superieurs a 40. La perte de pression est principalement controlee par les forces de frottement liquide/solide et les valeurs de perte de pression restent tres faibles en conditions de tests catalytiques (< 0,1 bar. Les caracteristiques hydrodynamiques indiquent donc que ce reacteur est approprie pour des tests catalytiques. Enfin, ce type de reacteur a ete mis en oeuvre en conditions de reactions catalytiques pour effectuer des tests d’un catalyseur commercial pour une reaction d’hydrogenation de l’allene. Le reacteur a permis d’effectuer des tests en conditions isothermes avec une tres faible quantite de catalyseur (inferieure a 2 cc et d’acceder aux performances catalytiques pour des temps de contact tres courts impossible a atteindre

  10. Revue des aspects hydrodynamiques des réacteurs catalytiques gaz-liquide-solide à lit fixe arrosé Hydrodynamics of Gas-Liquid-Solid Trickle-Bed Reactors: a Critical Review

    Directory of Open Access Journals (Sweden)

    Attou A.

    2006-12-01

    Full Text Available Bien que les aspects hydrodynamiques soient d'une importance primordiale lors de la conception et du fonctionnement d'un réacteur gaz-liquide-solide à lit fixe arrosé, les méthodes de calcul prédictif proposées sont restées fort rudimentaires. La plupart des études portant sur ce sujet ont été menées dans des conditions quasi atmosphériques alors que les réacteurs industriels fonctionnent à des pressions élevées. C'est seulement récemment que quelques résultats expérimentaux ont été obtenus à des hautes pressions, et des corrélations ont été proposées dans ces conditions pour prédire la transition entre les régimes ruisselant et pulsé, la perte de pression et le taux de rétention de liquide. L'objectif de cet article est double. D'une part, une synthèse y est présentée ; elle fait état des connaissances acquises sur les divers aspects hydrodynamiques du réacteur triphasique à lit fixe, incluant les récents développements réalisés à hautes pressions. D'autre part, les modèles et les corrélations actuels de transitions de régimes, de la perte de pression et du taux de rétention de liquide sont soumis à une analyse critique en confrontant leurs prédictions à l'ensemble des données expérimentales obtenues pour un large intervalle de la pression de fonctionnement du réacteur. Des conclusions objectives ont pu être tirées concernant les aptitudes des corrélations et des modèles actuels à être utilisées pour les calculs de conception des réacteurs triphasiques à lit fixe industriels. Malheureusement, il apparaît qu'aucun modèle de transitions entre les régimes ruisselant et pulsé n'est satisfaisant. Seule la corrélation empirique de Larachi et al. (1993 s'avère être jusqu'à présent la méthode la plus précise pour prédire la position de la frontière entre les régimes ruisselant et pulsé dans un large domaine de la pression de fonctionnement. Par ailleurs, aucune corr

  11. Periodic feedback stabilization for linear periodic evolution equations

    CERN Document Server

    Wang, Gengsheng

    2016-01-01

    This book introduces a number of recent advances regarding periodic feedback stabilization for linear and time periodic evolution equations. First, it presents selected connections between linear quadratic optimal control theory and feedback stabilization theory for linear periodic evolution equations. Secondly, it identifies several criteria for the periodic feedback stabilization from the perspective of geometry, algebra and analyses respectively. Next, it describes several ways to design periodic feedback laws. Lastly, the book introduces readers to key methods for designing the control machines. Given its coverage and scope, it offers a helpful guide for graduate students and researchers in the areas of control theory and applied mathematics.

  12. The redoubtable ecological periodic table

    Science.gov (United States)

    Ecological periodic tables are repositories of reliable information on quantitative, predictably recurring (periodic) habitat–community patterns and their uncertainty, scaling and transferability. Their reliability derives from their grounding in sound ecological principle...

  13. The redoubtable ecological periodic table

    Science.gov (United States)

    Ecological periodic tables are repositories of reliable information on quantitative, predictably recurring (periodic) habitat–community patterns and their uncertainty, scaling and transferability. Their reliability derives from their grounding in sound ecological principle...

  14. Doubly Resonant Optical Periodic Structure.

    Science.gov (United States)

    Alagappan, G; Png, C E

    2016-02-08

    Periodic structures are well known in various branches of physics for their ability to provide a stopband. In this article, using optical periodic structures we showed that, when a second periodicity--very closed to the original periodicity is introduced, large number of states appears in the stopband corresponding to the first periodicity. In the limit where the two periods matches, we have a continuum of states, and the original stopband completely disappears. This intriguing phenomena is uncovered by noticing that, regardless of the proximities of the two periodicities, there is an array of spatial points where the dielectric functions corresponding to the two periodicities interfere destructively. These spatial points mimic photonic atoms by satisfying the standards equations of quantum harmonic oscillators, and exhibit lossless, atom-like dispersions.

  15. Periodic review and continuous ordering

    OpenAIRE

    Prak, Dennis R.J.; Teunter, Ruud; Riezebos, Jan

    2014-01-01

    There exist many inventory control studies that consider either continuous review & continuous ordering, or periodic review & periodic ordering. Mixtures of the two are hardly ever studied. However, the model with periodic review and continuous ordering is highly relevant in practice, as information on the actual inventory level is not always up to date while making ordering decisions. This paper will therefore consider this case of periodic review and continuous ordering. Assuming zero fixed...

  16. Periodic review and continuous ordering

    NARCIS (Netherlands)

    Prak, Dennis; Teunter, Ruud; Riezebos, Jan

    2015-01-01

    Many inventory control studies consider either continuous review and continuous ordering, or periodic review and periodic ordering. Mixtures of the two are hardly ever studied. However, the model with periodic review and continuous ordering is highly relevant in practice, as information on the actua

  17. Periodic review and continuous ordering

    NARCIS (Netherlands)

    Prak, Dennis R.J.; Teunter, Ruud; Riezebos, Jan

    2014-01-01

    There exist many inventory control studies that consider either continuous review & continuous ordering, or periodic review & periodic ordering. Mixtures of the two are hardly ever studied. However, the model with periodic review and continuous ordering is highly relevant in practice, as information

  18. Periodic review and continuous ordering

    NARCIS (Netherlands)

    Prak, Dennis R.J.; Teunter, Ruud; Riezebos, Jan

    2014-01-01

    There exist many inventory control studies that consider either continuous review & continuous ordering, or periodic review & periodic ordering. Mixtures of the two are hardly ever studied. However, the model with periodic review and continuous ordering is highly relevant in practice, as information

  19. Periodic review and continuous ordering

    NARCIS (Netherlands)

    Prak, Dennis; Teunter, Ruud; Riezebos, Jan

    2015-01-01

    Many inventory control studies consider either continuous review and continuous ordering, or periodic review and periodic ordering. Mixtures of the two are hardly ever studied. However, the model with periodic review and continuous ordering is highly relevant in practice, as information on the

  20. Midy's Theorem for Periodic Decimals

    OpenAIRE

    Lewittes, Joseph

    2006-01-01

    The decimal expansion of 1/7 is 0.142857142857..., the block 142857 repeating forever. We call 142857 the period and its length is 6 = 2x3. If the period is broken into 2 pieces each of length 3 which are then added, the result is 142 + 857 = 999; similarly 14 + 28 + 57 = 99. Other periodic decimals show the same phenomenon while others do not. The general question then arises: Let a/N be a fraction with denominator prime to 10, having decimal expansion with period length dk, if the period is...

  1. The Hydrodynamic Characteristics of Cocurrent Downflow and Cocurrent Upflow Gas-Liquid-Solid Catalytic Fixed Bed Reactors: the Effect of Pressure Les caractéristiques hydrodynamiques des réacteurs gaz-liquide-solide à lit de catalyseur fixe à écoulement cocourant montant et descendant : l'influence de la pression

    Directory of Open Access Journals (Sweden)

    Wild G.

    2006-11-01

    Full Text Available While most catalytic fixed bed gas-liquid reactors of the petrol industry work at quite high pressures, the academic scientific work in this field concerned itself almost exclusively with the domain of approximatively atmospheric pressures. The authors present the results of some years of experimental investigations on the hydrodynamic characteristics of trickle bed reactors and lately of cocurrent upflow reactors. During the last years, results were also obtained under pressures up to 8 MPa. The measurements were made in a small scale cold flow equipment (diameter 23 mm. Different aqueous and organic more or less viscous, eventually coalescence inhibiting liquids, four gases and a number of non porous more or less wettable particles were used. The liquid holdup was determined in all cases by measuring liquid phase residence time distribution by different tracers. The following conclusions may be drawn:(a In the high interaction regime, it is the inertia of the gas and the liquid phases which is the main cause of the dissipation of mechanical energy. In this regime, results obtained in cocurrent upflow and downflow are approximately equal. (b Most correlations of literature are unable to predict the effect of pressure on the pressure drop or the liquid holdup. (c The gas viscosity has no influence on the hydrodynamics. It is therefore possible to simulate for example hydrogen under high pressure conditions by another gas of the same density (at a much lower pressures. A critical evaluation of the correlations and/or models of literature is presented, concerning their ability to represent the different characteristics as a function of pressure. Tandis que la plupart des réacteurs industriels gaz-liquide à lit de catalyseur fixe fonctionnent à assez hautes pressions, les travaux scientifiques académiques sont, dans ce domaine, presque exclusivement consacrés aux pressions avoisinant la pression atmosphérique. Les auteurs présentent les r

  2. Tunable deep ultraviolet femtosecond sum frequency laser based on Ba1-xB2-y-zO4SixAlyGaz crystal%Ba1-xB2-y-z O4SixAly Gaz晶体和频可调谐深紫外飞秒激光器∗

    Institute of Scientific and Technical Information of China (English)

    孟祥昊; 刘华刚; 黄见洪; 戴殊韬; 邓晶; 阮开明; 陈金明; 林文雄

    2015-01-01

    Tunable coherent deep ultraviolet (DUV) light sources, especially ultrashort pulse DUV lasers have great appli-cations in the fields of time-resolved, material processing, spectroscopy, laser spectroscopy and laser fusion. In the UV region, the best choice of generating the laser pulses in the femtosecond or picosecond regime is the frequency up-conversation technique based on second order nonlinearities. Over the past three decades, quite a lot of nonlinear crystals, such as LiB3O5, β-BaB2O4, KBe2BO3F2 and Ba1−xB2−y−zO4SixAlyGaz have been developed and employed for gener-ating the femtosecond pulses in the blue, ultraviolet, and even the deep-ultraviolet region. A tunable deep ultraviolet femtosecond laser is experimentally studied based on the new nonlinear crystal Ba1−xB2−y−zO4SixAlyGaz It is a kind of low-temperature phase barium metaborate single crystal belonging to a trigonal system, doped with one or more elements selected from Si, Al and Ga. As an optimized β-BaB2O4 crystal, Ba1−xB2−y−zO4SixAlyGaz completely overcomes the shortcomings of deliquescence compared withβ-BaB2O4, and its nonlinear efficiency and optical damage threshold have also been greatly improved. Using two crystals as second harmonic generation is to compensate for the spatial walk-off effect and the light path walk-off due to refraction effect The optical axis of the second Ba1−xB2−y−zO4SixAlyGaz is twice the phase matching angle with respect to the first one. In a femtosecond regime, short pulse provides high efficient frequency conversation due to their high peak powers, but the group velocity mismatch is a cognitive factor to limit conversion efficiency. It is obvious that after the frequency doubling, the second harmonic pulse and fundamental pulse separate from each other. The second harmonic pulse lags behind the fundamental pulse as they propagate through the crystal and the second harmonic pulse is broadened into a longer pulse duration than the

  3. Nonparametric Inference for Periodic Sequences

    KAUST Repository

    Sun, Ying

    2012-02-01

    This article proposes a nonparametric method for estimating the period and values of a periodic sequence when the data are evenly spaced in time. The period is estimated by a "leave-out-one-cycle" version of cross-validation (CV) and complements the periodogram, a widely used tool for period estimation. The CV method is computationally simple and implicitly penalizes multiples of the smallest period, leading to a "virtually" consistent estimator of integer periods. This estimator is investigated both theoretically and by simulation.We also propose a nonparametric test of the null hypothesis that the data have constantmean against the alternative that the sequence of means is periodic. Finally, our methodology is demonstrated on three well-known time series: the sunspots and lynx trapping data, and the El Niño series of sea surface temperatures. © 2012 American Statistical Association and the American Society for Quality.

  4. Positive periodic solutions of delayed periodic Lotka-Volterra systems

    Energy Technology Data Exchange (ETDEWEB)

    Lin Wei [Laboratory of Nonlinear Mathematics Science, Institute of Mathematics, Fudan University, Shanghai 200433 (China)]. E-mail: weilin@fudan.edu.cn; Chen Tianping [Laboratory of Nonlinear Mathematics Science, Institute of Mathematics, Fudan University, Shanghai 200433 (China)]. E-mail: tchen@fudan.edu.cn

    2005-01-17

    In this Letter, for a general class of delayed periodic Lotka-Volterra systems, we prove some new results on the existence of positive periodic solutions by Schauder's fixed point theorem. The global asymptotical stability of positive periodic solutions is discussed further, and conditions for exponential convergence are given. The conditions we obtained are weaker than the previously known ones and can be easily reduced to several special cases.

  5. GAZ - slishkom vremennaja alternativa / Roman Vikulov

    Index Scriptorium Estoniae

    Vikulov, Roman

    2005-01-01

    Narva linna küttekomisjoni poolt organiseeritud seminarist, kus osales ka Põhjamaade juhtivasse energeetikakompaniisse kuuluva kontserni Fortum Termest arengudirektor Kaido-Paul Bõstrov ja Vene Föderatsiooni majandusministeeriumi riiklik ekspert, akadeemik Vladimir Borovkov

  6. Gaz nam ne ukaz / Josef Kats

    Index Scriptorium Estoniae

    Kats, Josef, 1977-

    2007-01-01

    Valitsuse eitavast otsusest Vene-Saksa gaasijuhtme uuringute taotlusele, välisminister Urmas Paeti kommentaaridest pressikonverentsil. Välisminister leiab, et antud olukorras oli valitsuse otsus ainuõige

  7. Gaz nam ne ukaz / Josef Kats

    Index Scriptorium Estoniae

    Kats, Josef, 1977-

    2007-01-01

    Valitsuse eitavast otsusest Vene-Saksa gaasijuhtme uuringute taotlusele, välisminister Urmas Paeti kommentaaridest pressikonverentsil. Välisminister leiab, et antud olukorras oli valitsuse otsus ainuõige

  8. Liquefied natural gas; Gaz naturel liquefie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Total has interests in five of the world's largest liquefaction plants, which together account for roughly 40% of global LNG production capacity. This presentation illustrates the activities of the Group in the LNG sector. It discusses the advantages of the LNG as a clean energy, the LNG market, the liquefaction process and plants, the LNG trading marketing and shipping, the re-gasification and TOTAL promoting innovation. (A.L.B.)

  9. GAZ - slishkom vremennaja alternativa / Roman Vikulov

    Index Scriptorium Estoniae

    Vikulov, Roman

    2005-01-01

    Narva linna küttekomisjoni poolt organiseeritud seminarist, kus osales ka Põhjamaade juhtivasse energeetikakompaniisse kuuluva kontserni Fortum Termest arengudirektor Kaido-Paul Bõstrov ja Vene Föderatsiooni majandusministeeriumi riiklik ekspert, akadeemik Vladimir Borovkov

  10. [Periodic breathing with periodic oxygen variation in infancy].

    Science.gov (United States)

    von Czettritz, G; Bax, R T; Eckardt, T; Springer, S; Emmrich, P

    1996-01-01

    Oxycardiorespirographies, recording arterial oxygen saturation (SaO2), breathing movements, heart rate and ECG with a mean recording time of 22.3 hours, were performed on 85 preterm (mean postconceptional age: 38 weeks) and 81 term infants (mean postconceptional age 42.4 weeks). 83% of the preterm infants showed periodic breathing (PB), in 97% of them this was accompanied by periodic variations of arterial oxygen saturation (PVO). Periodic breathing occurred in 61% of the term infants, 84% of them showed PVO during periodic breathing. The mean variation of oxygen saturation was between 92.8 and 96.8% (+/- 1.7) for preterm and between 92.9 and 96.0% (+/- 2.2) for term infants. In some infants the peak to peak amplitude of the SaO2 cycles was up to 22%, sometimes a further fall of SaO2 occurred. There was a strong correlation of the PVO both at the beginning and end of the episode as well as with the PB-cycle periodicity itself. The fall of the oxygen saturation occurred 3.1 to 7.8 s after the beginning of the first apnea of an episode of periodic breathing, the minimum SaO2 was reached approximately 4.2 to 8.6 s later. This periodic rapid fall of SaO2 from a high oxygenation level cannot be explained by the apneas of a rather short duration during periodic breathing. It is discussed that PVO during periodic breathing may be caused by an ideopathic right to left shunting across fetal circulation pathways which occurs intermittently and periodically. This mechanism could-via patterns of reaction exhibited during the fetal and neonatal time period-lead to acute hypoxemia, as found in apparently life threatening events (ALTE) and as postulated in sudden infant death (SID).

  11. Geochemical Study of Natural CO2 Emissions in the French Massif Central: How to Predict Origin, Processes and Evolution of CO2 Leakage Étude géochimique des émissions naturelles de CO2 du Massif Central : origine et processus de migration du gaz

    Directory of Open Access Journals (Sweden)

    Battani A.

    2010-05-01

    de surveillance des futurs sites de stockage de CO2. Au cours des campagnes de terrain, nous avons analysé des flux de CO2 entre le sol et l’atmosphère, et nous avons prélevé et analysé à la fois des gaz des sols, et du gaz provenant de sources carbo-gazeuses, présentes dans toute la région. Un dispositif de « monitoring continu » dans le temps a également été testé, afin d’enregistrer conjointement les teneurs en CO2 de l’atmosphère et dans le sol en un point précis. Nous avons pu mettre au point un suivi géochimique basé sur la composition isotopique des gaz rares prélevés dans les sols. L’ensemble de nos résultats, confronté à la géologie de terrain, nous a permis de mettre en évidence l’origine mantellique du CO2. Ce CO2 remonte rapidement à la surface à l’état gazeux, le long de failles normales et/ou décrochantes, actives actuellement. Les teneurs et flux de CO2 dans le sol sont spatialement variables et élevés, et montrent également une origine mantellique. Les teneurs atmosphériques semblent faiblement augmenter par rapport à l’important dégazage observé dans la région.

  12. Surface Gas Geochemistry above the Natural CO2 Reservoir of Montmiral (Drôme, France, Source Tracking and Gas Exchange between the Soil, Biosphere and Atmosphere Échanges gazeux et géochimie des gaz à la surface du réservoir naturel profond de CO2 de Montmiral (Drôme

    Directory of Open Access Journals (Sweden)

    Gal F.

    2010-07-01

    Full Text Available One of the options considered to mitigate greenhouse gas concentrations in the atmosphere is underground storage of CO2. There is a strong need for enhancing and developing methods that would help throughout the duration life of such underground storage, to ensure the safety and able to monitor the evolution of the injected CO2 plume. Among these, geochemical methods can play an important role. Here, we describe results acquired under the research programme “Géocarbone-Monitoring”, partially funded by the French National Research Agency, on the Montmiral natural analogue in South-Eastern France. Other results obtained under the same research programme in the French Massif Central are reported elsewhere in this volume. Spot sampling methods allowing a great geographical coverage and continuous measurements on selected points were undertaken in 2006 and 2007, in order to determine soil gas concentrations and fluxes as well as carbon isotope ratio determinations. One important result is that without any evidence of deep CO2 leakage, both CO2 concentrations and fluxes appear to be higher than can be explained only by biological activities. Further investigations are thus needed to understand the gas evolution better throughout the year. Une des options envisagées pour réguler les concentrations de gaz à effet de serre dans l’atmosphère est le stockage souterrain du CO2. Dans ce domaine existe un fort besoin de renforcer et de développer des méthodes susceptibles d’être utilisées tout au long de la durée de vie de ces stockages souterrains, afin de s’assurer de leur sécurité et de pouvoir suivre l’évolution du panache de CO2 injecté. Parmi elles, les méthodes géochimiques peuvent jouer un rôle important. Nous décrivons ici les résultats acquis dans le cadre du programme de recherche « Géocarbone-Monitoring » financé en partie par l’Agence Nationale de la Recherche sur l’analogue naturel de Montmiral dans le Sud

  13. Visualisation of Gasoline and Exhaust Gases Distribution in a 4-Valve Si Engine; Effects of Stratification on Combustion and Pollutants Visualisation de la répartition du carburant et des gaz brûlés dans un moteur à 4 soupapes à allumage commandé ; effet de la stratification sur la combustion et les polluants

    Directory of Open Access Journals (Sweden)

    Deschamps B.

    2006-12-01

    Full Text Available sAn indirect method to map the burned gases in SI engine has been developed. It is based on visualisation by Laser Induced Fluorescence of the unburned mixture seeded with biacetyl. Both internally and externally recirculated burned gases are monitored. This diagnostic is complementary to the LIF technique applied to measure the gasoline distribution. These LIF gasoline and burned gases measurements are applied in a 4-valve optical access SI engine for a large range of operating conditions. These include variations of both fuel injection and burned gas recirculation modes causing different types of stratification leading to very distinct heat release and exhaust emissions characteristics. Tumble level and spark location are also modified. The observation of the actual stratification in the engine forms a sound basis explanation of the engine performance. Parameters allowing an optimisation of NOx and HC levels can be inferred, and in particular the effectiveness of recirculation and fuel injection strategies. The conclusions are confirmed by measurements in a single engine cylinder conventional head with the same geometry. Une méthode indirecte pour cartographier les gaz brûlés dans un moteur à allumage commandé a été développée. Elle est fondée sur une visualisation à partir de la fluorescence induite par laser (LIF du mélange air-carburant non brûlé et ensemencé avec du biacétyl. Les gaz brûlés provenant à la fois des recirculations internes et externes sont observés. Ce type de diagnostic est complémentaire des techniques de LIF utilisées pour observer la distribution du carburant. Ces mesures de concentration sont réalisées dans un moteur à 4 soupapes avec accès optiques, pour une gamme étendue de conditions opératoires. Celles-ci comprennent des variations des modes d'injection du carburant et des modes de recirculation des gaz brûlés, provoquant ainsi différents types de stratifications qui correspondent

  14. Repelling periodic points of given periods of rational functions

    Institute of Scientific and Technical Information of China (English)

    CHANG Jianming; FANG Mingliang

    2006-01-01

    Let R(z) be a rational function of degree d ≥ 2. Then R(z) has at least one repelling periodic point of given period k ≥ 2, unless k = 4 and d=2, or k= 3 and d ≤ 3, or k=2 and d≤8. Examples show that all exceptional cases occur.

  15. From Periodic Properties to a Periodic Table Arrangement

    Science.gov (United States)

    Besalú, Emili

    2013-01-01

    A periodic table is constructed from the consideration of periodic properties and the application of the principal components analysis technique. This procedure is useful for objects classification and data reduction and has been used in the field of chemistry for many applications, such as lanthanides, molecules, or conformers classification.…

  16. From Periodic Properties to a Periodic Table Arrangement

    Science.gov (United States)

    Besalú, Emili

    2013-01-01

    A periodic table is constructed from the consideration of periodic properties and the application of the principal components analysis technique. This procedure is useful for objects classification and data reduction and has been used in the field of chemistry for many applications, such as lanthanides, molecules, or conformers classification.…

  17. On the Period-Amplitude and Amplitude-Period Relationships

    Science.gov (United States)

    Wilson, Robert M.; Hathaway, David H.

    2008-01-01

    Examined are Period-Amplitude and Amplitude-Period relationships based on the cyclic behavior of the 12-month moving averages of monthly mean sunspot numbers for cycles 0.23, both in terms of Fisher's exact tests for 2x2 contingency tables and linear regression analyses. Concerning the Period-Amplitude relationship (same cycle), because cycle 23's maximum amplitude is known to be 120.8, the inferred regressions (90-percent prediction intervals) suggest that its period will be 131 +/- 24 months (using all cycles) or 131 +/- 18 months (ignoring cycles 2 and 4, which have the extremes of period, 108 and 164 months, respectively). Because cycle 23 has already persisted for 142 months (May 1996 through February 2008), based on the latter prediction, it should end before September 2008. Concerning the Amplitude-Period relationship (following cycle maximum amplitude versus preceding cycle period), because cycle 23's period is known to be at least 142 months, the inferred regressions (90-percent prediction intervals) suggest that cycle 24's maximum amplitude will be about less than or equal to 96.1 +/- 55.0 (using all cycle pairs) or less than or equal to 91.0 +/- 36.7 (ignoring statistical outlier cycle pairs). Hence, cycle 24's maximum amplitude is expected to be less than 151, perhaps even less than 128, unless cycle pair 23/24 proves to be a statistical outlier.

  18. Proposition d'explication de la formation d'hydrogène sulfuré dans les stockages souterrains de gaz naturel par réduction des sulfures minéraux de la roche magasin Proposed Explanation of Hydrogen-Sulfide Formation in Underground Natural-Gas Storage Structures by Reduction of Mineral Sulfides in the Reservoir Rock.

    Directory of Open Access Journals (Sweden)

    Bourgeois J. P.

    2006-11-01

    Full Text Available La formation d'hydrogène sulfuré dans les structures de stockage peu expliquer autrement que par l'action de bactéries sulfato-réductrices. La contenue dans la roche magasin constitue une source de sulfures capable d'alimenter en H2S le gaz naturel. La réduction de la pyrite en sulfures du type Fe 1-x S et l'équilibre de dissolution précipitation, lié principalement à la pression de CO2, dans les structures stockages, constituent un processus de formation d'H2S capable d'expliquer tativement et quantitativement les phénomènes observés sur le terrain. Un modèle simplifié de stockage reprend ce schéma et teste la sensibililté de la teneur en H2S à la valeur des paramètres physiques et chimiques définissant le stockage. Cette étude permet de proposer un certain nombre d'actions susceptibles de limiter la formation d'H2S et d'orienter les choix futurs du couple gaz naturel - structures de stockage. The formation of hydrogen sulfide in storage structures can be explained otherwise thon by the action of sulfate-reducing bacteria. The pyrite contained in the reservoir rock makes up a source of sulfides capable of supplying the natural gas with H2S.Reduction of pyrite ta sulfides of the Fe,-,S type and the dissolution precipitation equilibrium, linked mainly ta C02 pressure in storage structures, make up an H2S for-mation process capable of qualitatively and quantitatively explained phenomena observed in the field.A simplified storage model reflects this scheme and can be used ta test the sensi-tivity of the H2S content ta the value of the physical and chemical parameters defining the storage structure.This investigation can be used to propose various means of action (sable ta "mit H2S formation and ta guide future choices of natural gas/storage-structure pairs.

  19. Latino Periodicals: A Selection Guide.

    Science.gov (United States)

    Guerena, Salvador, Ed.; Pisano, Vivian M., Ed.

    This guide is a collection development tool of national scope for librarians who need in-depth coverage of Latino periodicals suitable for public, school, and academic libraries. Periodicals evaluated include general interest and popular magazines and newspapers that appeal to Spanish-speaking, bilingual, and English-speaking library patrons and…

  20. Mesure et modélisation multidimensionnelle des transferts thermiques gaz-paroi dans le cas des moteurs à allumage commandé Measurement and Multidimensional Modeling of Gas-Wall Heat Transfers in Spark-Ignition Engines

    Directory of Open Access Journals (Sweden)

    Gilaber P.

    2006-11-01

    Full Text Available A cette fin, deux étapes de recherche ont été mises en oeuvre : une phase expérimentale et une phase calcul. Dans la phase expérimentale, des mesures ont été faites sur un moteur monocylindre équipé de flux-mètres à réponse rapide. Chaque flux-mètre est composé d'un cylindre d'acier, contenant deux thermocouples. Dans le but de montrer l'influence de l'aérodynamique sur les échanges thermiques, un anémomètre à Laser a été utilisé à l'aide d'une entretoise placée entre culasse et cylindre. L'entretoise comportait deux hublots et deux flux-mètres permettant la mesure simultanée des flux thermiques et des paramètres aérodynamiques à l'extérieur de la couche limite. Deux flux-mètres supplémentaires ont été placés dans la culasse et le système d'acquisition permettait d'enregistrer simultanément dix voies de mesure à chaque degré vilebrequin, parmi lesquelles deux composantes de vitesse et la pression cylindre. Une étude paramétrique a révélé les tendances suivantes : - les pertes globales aux parois au cours d'un cycle thermodynamique diminuent lorsque le régime augmente, mais la valeur maximale des flux locaux augmente en raison de l'élévation du niveau de turbulence; - le remplissage a peu d'effet sur l'aérodynamique; son influence sur les transferts thermiques est due principalement à l'augmentation de la densité des gaz, qui se traduit par une augmentation des flux. Dans la phase calcul, deux idées de base ont guidé notre travail : - pour des raisons de temps de calcul prohibitif, il est impossible de mailler la couche limite; les échanges thermiques ont donc été estimés à l'aide d'une loi de paroi; - on fait l'hypothèse que les champs locaux de densité, vitesse et turbulence conditionnent fortement les flux thermiques; ce seront les paramètres de la loi de paroi. Dans cet esprit, le modèle de transferts thermiques de DIWAKAR a été introduit dans le code multi-dimensionnel KIVA. Une

  1. Construction of the core of the 'heavy water-gas' reactor EL 4; Structures du coeur du reacteur 'eau- lourde-gaz EL 4'

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, J.L.; Foulquier, H.; Thome, P. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    problem of thermal insulation around a zirconium alloy liner tube. The neutron absorption equivalent is about 1, 1 mm of Al, and the mean loss around 2 p. 100 of the thermal power of the reactor. The methods proposed have proved practicable as a result of important research and developments on automatic remote control for all the operations which make up the sequences of mounting, demounting and repairing of the construction components. In particular the possibilities opened up by the new techniques of welding tubes from the inside have been extended to other problems connected with the assembling of a reactor. (authors) [French] Le coeur de ce reacteur est constitue par une cuve contenant l'eau lourde, cuve traversee d'une serie de tubes de force dans lesquels circule le gaz caloporteur sous pression de 60 at. Les specifications de depart qui ont joue un role important dans la conception de ces structures concernent des aspects de securite de fonctionnement (chargement du combustible par les deux faces du reacteur, remplacement des structures sur les deux faces du reacteur), des necessites neutroniques (absorption des structures minimum, pas du reseau, diametre des tubes de force) et des considerations thermiques (temperature de sortie 500 C). Ces specifications ont entraine une disposition horizontale des tubes de force et des problemes d'encombrement tres delicats qui ont elimine (pour les dimensions d'EL 4) toute possibilite de recourir a des compensateurs de dilatation sur les tubes de force. II s'ensuit un dessin de cuve semi-rigide dans lequel les tubes de force contribuent pour une part importante a la resistance mecanique de l'ensemble en jouant le role de tirant, d'ou des contraintes elevees sur les jonctions et tubes de force (et le choix des alliages de zirconium). Les structures comprennent le tube de force, les jonctions, l'isolement thermique et le tube de guidage. On expose brievement les moyens d'essais mis en

  2. Optical Periodicity Analysis of 3C 446 using Period04

    Indian Academy of Sciences (India)

    Fei Guo; Hao Jing Zhang

    2014-09-01

    All the data of the blazar 3C446 at 8, 4.8, 14 and 22 GHz, presented in publications from 1977 to 2006, have been compiled to generate light curves. The light curves show violent activity of 3C446. Using Period04 analysis method, we have found that there is a period of 7.2 yr, which is consistent with the results that we found using wavelet analysis method. We get the instability region as = 123.83.

  3. The Periodic Table in Croatia

    Directory of Open Access Journals (Sweden)

    Raos, N.

    2011-12-01

    Full Text Available The Croatian (Yugoslav Academy of Sciences and Arts was the first academy to elect D. I. Mendeleev as its honorary member (1882, whereas the periodic table of the elements has been taught regularly at the Zagreb University since 1888. The early interest of Croatian chemists in the periodic table should be attributed primarily to their pan-Slavic attitude, particularly as proof that Slavic people were able to produce "their own Newtons" (M. V. Lomonosov and D. I. Mendeleev. Such enthusiastic views, however, did not help in analyzing the contribution of Mendeleev and other scientists to the discovery and development of the periodic table of the elements.

  4. Periodic insolation variations on Mars.

    Science.gov (United States)

    Murray, B C; Ward, W R; Yeung, S C

    1973-05-11

    Previously unrecognized insolation variations on Mars are a consequence of periodic variations in eccentricity, first established by the theory of Brouwer and Van Woerkom (1950). Such annual insolation variations, characterized by both 95,000-year and 2,000,000-year periodicities, may actually be recorded in newly discovered layered deposits in the polar regions of Mars. An additional north-south variation in seasonal insolation, but not average annual insolation, exists with 51,000-year and 2,000,000-year periodicities.

  5. 75 FR 1301 - Periodic Reporting

    Science.gov (United States)

    2010-01-11

    ... From the Federal Register Online via the Government Publishing Office POSTAL REGULATORY COMMISSION 39 CFR Part 3050 Periodic Reporting AGENCY: Postal Regulatory Commission. ACTION: Proposed rule; notice of availability of rulemaking petition. SUMMARY: The Postal Service has proposed adjustments to...

  6. Measuring Scars of Periodic Orbits

    CERN Document Server

    Kaplan, L

    1999-01-01

    The phenomenon of periodic orbit scarring of eigenstates of classically chaotic systems is attracting increasing attention. Scarring is one of the most important ``corrections'' to the ideal random eigenstates suggested by random matrix theory. This paper discusses measures of scars and in so doing also tries to clarify the concepts and effects of eigenfunction scarring. We propose a new, universal scar measure which takes into account an entire periodic orbit and the linearized dynamics in its vicinity. This measure is tuned to pick out those structures which are induced in quantum eigenstates by unstable periodic orbits and their manifolds. It gives enhanced scarring strength as measured by eigenstate overlaps and inverse participation ratios, especially for longer orbits. We also discuss off-resonance scars which appear naturally on either side of an unstable periodic orbit.

  7. Autism: a "critical period" disorder?

    Science.gov (United States)

    LeBlanc, Jocelyn J; Fagiolini, Michela

    2011-01-01

    Cortical circuits in the brain are refined by experience during critical periods early in postnatal life. Critical periods are regulated by the balance of excitatory and inhibitory (E/I) neurotransmission in the brain during development. There is now increasing evidence of E/I imbalance in autism, a complex genetic neurodevelopmental disorder diagnosed by abnormal socialization, impaired communication, and repetitive behaviors or restricted interests. The underlying cause is still largely unknown and there is no fully effective treatment or cure. We propose that alteration of the expression and/or timing of critical period circuit refinement in primary sensory brain areas may significantly contribute to autistic phenotypes, including cognitive and behavioral impairments. Dissection of the cellular and molecular mechanisms governing well-established critical periods represents a powerful tool to identify new potential therapeutic targets to restore normal plasticity and function in affected neuronal circuits.

  8. Periodicities in photospheric magnetic flux

    Institute of Scientific and Technical Information of China (English)

    SONG; Wenbin; WANG; Jingxiu

    2006-01-01

    Magnetic field plays an important role in solar structure and activity. In principle, the determination of magnetic flux would provide the best general-purpose index of solar activity. Currently, the periodicity studies corresponding to photospheric magnetic flux (PMF) are very few possibly due to the absence of a uniform flux sequence. In this paper, by using 383 NSO/Kitt Peak magnetic synoptic charts we reconstruct a flux sequence from February 1975 to August 2003 and perform a relatively systemic periodicity analysis with two methods of the Scargle periodogram and the Morlet wavelet transform. As a result, four periods are found at around 1050, 500, 300 and 160 days. We analyze these periods' temporal variabilities in detail and discuss their respective origins briefly.

  9. Period Integrals and Tautological Systems

    CERN Document Server

    Lian, Bong H; Yau, Shing-Tung

    2011-01-01

    We study period integrals of CY hypersurfaces in a partial flag variety. We construct a holonomic system of differential equations which govern the period integrals. By means of representation theory, a set of generators of the system can be described explicitly. The results are also generalized to CY complete intersections. The construction of these new systems of differential equations have lead us to the notion of a tautological system.

  10. Period-doubling cascades galore

    OpenAIRE

    Sander, Evelyn; Yorke, James A.

    2009-01-01

    The appearance of numerous period-doubling cascades is among the most prominent features of {\\bf parametrized maps}, that is, smooth one-parameter families of maps $F:R \\times {\\mathfrak M} \\to {\\mathfrak M}$, where ${\\mathfrak M}$ is a smooth locally compact manifold without boundary, typically $R^N$. Each cascade has infinitely many period-doubling bifurcations, and it is typical to observe -- such as in all the examples we investigate here -- that whenever there are any cascades, there are...

  11. Periodic billiard trajectories in polyhedra

    CERN Document Server

    Bedaride, Nicolas

    2011-01-01

    We consider the billiard map inside a polyhedron. We give a condition for the stability of the periodic trajectories. We apply this result to the case of the tetrahedron. We deduce the existence of an open set of tetrahedra which have a periodic orbit of length four (generalization of Fagnano's orbit for triangles), moreover we can study completly the orbit of points along this coding.

  12. Jupiter and Saturn Rotation Periods

    CERN Document Server

    Helled, Ravit; Anderson, John D

    2009-01-01

    Anderson & Schubert (2007, Science,317,1384) proposed that Saturn's rotation period can be ascertained by minimizing the dynamic heights of the 100 mbar isosurface with respect to the geoid; they derived a rotation period of 10h 32m 35s. We investigate the same approach for Jupiter to see if the Jovian rotation period is predicted by minimizing the dynamical heights of its isobaric (1 bar pressure level) surface using zonal wind data. A rotation period of 9h 54m 29s is found. Further, we investigate the minimization method by fitting Pioneer and Voyager occultation radii for both Jupiter and Saturn. Rotation periods of 9h 55m 30s and 10h 32m 35s are found to minimize the dynamical heights for Jupiter and Saturn, respectively. Though there is no dynamical principle requiring the minimization of the dynamical heights of an isobaric surface, the successful application of the method to Jupiter lends support to its relevance for Saturn. We derive Jupiter and Saturn rotation periods using equilibrium theory in ...

  13. Influence de la pression et de la non-idéalité des gaz dans le calcul d'un réacteur d'ammoniac Influence of Gas Pressure and Non-Iddeality on Designing an Ammonia Reactor

    Directory of Open Access Journals (Sweden)

    Scheiderman B.

    2006-11-01

    Full Text Available Le mélange gazeux qui parcourt un réacteur de synthèse d'ammoniac présente des écarts notables par rapport aux gaz idéaux. On a établi les équations de calcul d'un réacteur à gradient thermique optimum en tenant compte de l'influence de ces écarts sous trois pressions d'opération (150, 300 et 500 atm.. On a vérifié que les corrections principales à effectuer sont dues à la fugacité; les autres sont d'une importance moindre, et affectent surtout le contrôle du réacteur. En outre, on a mis en évidence l'influence considérable de la pression totale. The gaseous mixture flowing through an ommonia synthesis reactor shows considerable divergences from the behovior of ideal gases. These divergences are examined at three operating pressures (150, 300 and 500 atm, and the corresponding design equations for an optimum temperature progression are determined. The main diver gences are those caused by fugacity. The others are of lesser importance. At the same time, the great influence of total pressure is demonstrated.

  14. Project of law modified by the Senate relative to the electric and gas public utilities and to the electric and gas companies; Projet de loi modifie par le Senat relatif au service public de l'electricite et du gaz et aux entreprises electriques et gazieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This project of law aims to adapt the electricity and gas sector to the new economical context of opening of the energy markets to competition. It gives to energy companies the internal organization base necessary to warrant a high level of service and a transparent and non-discriminatory access of third parties to transport and distribution networks. These evolutions will allow Electricite de France (EdF) and Gaz de France (GdF) companies to compete on equal terms with their European competitors. It confirms first the prime role of public utility of both companies and then transposes the dispositions of the European directives relative to the organization of EdF and GdF integrated companies. It foresees the creation of two daughter companies for the management of energy transport activities. The project of law foresees also the change of the status of EdF and GdF companies and the reform of the retirement pensions of the personnel. This report presents the modifications added by the Senate to the text of law adopted at first reading by the House of Commons. (J.S.)

  15. Law project modified by the Senate after urgency declaration relative to the electric and gas public utilities and to the power and gas companies; Projet de loi modifie par le Senat apres declaration d'urgence relatif au service public de l'electricite et du gaz et aux entreprises electriques et gazieres

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This document is the modifications made by the French Senate after the first reading of the law project adopted by the House of Commons and relative to the change of status of the power and gas public utilities in the framework of the deregulation of European energy markets. This law changes the juridical status of the two state monopolies Electricite de France (EdF) and Gaz de France (GdF) into two anonymous companies and creates two additional companies for the management of the power and gas networks. It ensures also the transposition of the European directives from June 26, 2003 (2003/54/CE and 2003/55/CE). It contains some proper dispositions and modifies various existing French laws, in particular the law no. 46-628 from April 8, 1946 about the electricity and gas nationalization and the law no. 2000-108 from February 10, 2000 relative to the modernization and development of the electric public utility. The document lists the modifications made by the Senate article by article. (J.S.)

  16. Periodic Sweep Coverage Scheme Based on Periodic Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Li Shu

    2014-03-01

    Full Text Available We provide a sweep coverage algorithm for routing mobile sensors that communicate with a central data sink. This algorithm improves on its predecessors by reducing the number of unnecessary scans when different points of interest (POIs have different requirements for the time interval within which they must be scanned (sweep period. Most sweep coverage algorithms seek to minimize the number of sensors required to cover a given collection of POIs. When POIs have different sweep period requirements, existing algorithms will produce solutions in which sensors visit some POIs much more frequently than is necessary. We define this as the POI Over-Coverage problem. In order to address this problem we develop a Periodic Sweep Coverage (PSC scheme based on a well-known solution to the Periodic Vehicle Routing Problem (PVRP. Our algorithm seeks a route for the mobile sensors that minimizes the number of unnecessary visits to each POI. To verify and test the proposed scheme we implemented a C++ simulation and ran scenarios with a variety of POI topologies (number and distribution of the POIs and the speed at which sensors could travel. The simulation results show that the PSC algorithm outperforms other sweep coverage algorithms such as CSweep and Vehicle Routing Problem Sweep Coverage (VRPSC on both the average number of sensors in a solution and in the computational time required to find a solution. Our results also demonstrate that the PSC scheme is more suitable for the sweep coverage scenarios in which higher speed mobile sensors are used.

  17. Periodicity, the Canon and Sport

    Directory of Open Access Journals (Sweden)

    Thomas F. Scanlon

    2015-10-01

    Full Text Available The topic according to this title is admittedly a broad one, embracing two very general concepts of time and of the cultural valuation of artistic products. Both phenomena are, in the present view, largely constructed by their contemporary cultures, and given authority to a great extent from the prestige of the past. The antiquity of tradition brings with it a certain cachet. Even though there may be peripheral debates in any given society which question the specifics of periodization or canonicity, individuals generally accept the consensus designation of a sequence of historical periods and they accept a list of highly valued artistic works as canonical or authoritative. We will first examine some of the processes of periodization and of canon-formation, after which we will discuss some specific examples of how these processes have worked in the sport of two ancient cultures, namely Greece and Mesoamerica.

  18. Inflation from periodic extra dimensions

    CERN Document Server

    Higaki, Tetsutaro

    2016-01-01

    We discuss a realization of a small field inflation based on string inspired supergravities. In theories accompanying extra dimensions, compactification of them with small radii is required for realistic situations. Since the extra dimension can have a periodicity, there will appear (quasi-)periodic functions under transformations of moduli of the extra dimensions in low energy scales. Such a periodic property can lead to a UV completion of so-called multi-natural inflation model where inflaton potential consists of a sum of multiple sinusoidal functions with a decay constant smaller than the Planck scale. As an illustration, we construct a SUSY breaking model, and then show that such an inflaton potential can be generated by a sum of world sheet instantons in intersecting brane models on extra dimensions containing $T^2/{\\mathbb Z}_2$ orbifold. We show also predictions of cosmic observables by numerical analyzes.

  19. Periodicity and repeatability in data

    Science.gov (United States)

    Southwood, D.

    Using magnetic data from the first two years in Saturn orbit, the basic periodicity of apparent is examined with the aim of elucidating the `cam' shaft model of Espinosa et al. (2003) identifying the nature of the `cam' and giving a definitive period for its rotation. An initial hypothesis, supported by the spectral analysis of analysis of the first 8 months in orbit Gianpieri et al. (2006), is made that the source of the period is linked to something inside the planet and therefore that the source inertia means that the period effectively does not change over the 2 years. Moreover one expects that the source phase is fixed. Using this approach, not only can the period identified by spectral analysis (647.1 + 0.6 min.) be verified but also by phase analysis between successive passes over the 2 years the period can be refined to 647.6 + 0.1 min. The signal itself is remarkably reproducible from pass to pass. It appears in all three components of the field and its polarisation is unambiguously not attributable to direct detection of an internal field. Not only does the signal not decay rapidly with distance from the planet, but although it has the m=1 symmetry of a tilted dipole, the field lines diverge from the planet indicating an exterior source. This feature led to the `cam' model. The polarisation and comparisons of passes with different latitude profiles show a surprising north-south symmetry in the azimuthal field. The absence of asymmetry with respect to the magnetic equator rules out a direct magnetospheric-ionospheric interaction source. Accordingly, it is proposed that the basic `cam' effect is generated by a single hemisphere anomaly which creates hemisphere to hemisphere field aligned currents. The existence of Saturn phase related anomaly appears to produce a basic asymmetry in the inner magnetosphere that sets the phase of both an inflowing and outflowing sector in a rotating circulation system.

  20. Hydrogen purification by periodic adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Barg, Christian; Secchi, Argimiro R.; Trierweiler, Jorge O. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Engenharia Quimica]. E-mail: cbarg@enq.ufrgs.br; arge@enq.ufrgs.br; jorge@enq.ufrgs.br

    2000-07-01

    The periodic adsorption processes have been widely used for industrial applications, mainly because it spends less energy than the usual gas separation processes, like the cryogenic distillation. The largest commercial application of periodic adsorption processes is the pressure swing adsorption (PSA) applied to hydrogen purification. Although its wide use in the chemical and petrochemical industry, there are no reports in the open literature about complete modeling studies of a complex commercial unit, with multiple adsorbents and multiple beds and several feed components. This study has as objective the modeling, optimization and dynamical analysis of an industrial PSA unit for hydrogen purification. (author)

  1. Sigmoid Volvulus Complicating Postpartum Period

    Science.gov (United States)

    Blake, Erin; Gonzalez, Eduardo; Pieracci, Frederic

    2017-01-01

    Background. Sigmoid volvulus is a rare complication of pregnancy and the puerperium. Case. A 19-year-old patient, gravida 1 para 0 at 41 0/7 weeks of gestation, admitted for late-term induction of labor underwent an uncomplicated primary low transverse cesarean delivery for arrest of descent. Her postoperative period was complicated by sudden onset of abdominal pain and the ultimate diagnosis of sigmoid volvulus. Conclusion. Prompt surgical evaluation of an acute abdomen in the postpartum period is essential; delayed diagnosis and treatment can lead to significant maternal morbidity and mortality.

  2. Sigmoid Volvulus Complicating Postpartum Period

    Directory of Open Access Journals (Sweden)

    Kelsey E. Ward

    2017-01-01

    Full Text Available Background. Sigmoid volvulus is a rare complication of pregnancy and the puerperium. Case. A 19-year-old patient, gravida 1 para 0 at 41 0/7 weeks of gestation, admitted for late-term induction of labor underwent an uncomplicated primary low transverse cesarean delivery for arrest of descent. Her postoperative period was complicated by sudden onset of abdominal pain and the ultimate diagnosis of sigmoid volvulus. Conclusion. Prompt surgical evaluation of an acute abdomen in the postpartum period is essential; delayed diagnosis and treatment can lead to significant maternal morbidity and mortality.

  3. PERIODIC COMPLEMENTARY BINARY SEQUENCE PAIRS

    Institute of Scientific and Technical Information of China (English)

    XuChengqian; ZhaoXiaoqun

    2002-01-01

    A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP)is proposed .A new class of block design-Difference Family Pair (DFP)is also proposed .The relationship between PCSP and DFP,the properties and exising conditions of PCSP and the recursive constructions for PCSP are given.

  4. PERIODIC COMPLEMENTARY BINARY SEQUENCE PAIRS

    Institute of Scientific and Technical Information of China (English)

    Xu Chengqian; Zhao Xiaoqun

    2002-01-01

    A new set of binary sequences-Periodic Complementary Binary Sequence Pair (PCSP) is proposed. A new class of block design-Difference Family Pair (DFP) is also proposed.The relationship between PCSP and DFP, the properties and existing conditions of PCSP and the recursive constructions for PCSP are given.

  5. Glass Waveguides for Periodic Poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    Planar silica-based waveguide devices have been developed for second-harmonic generation by poling with periodic electrodes. We show that detrimental charge transport can occur along interfaces, but with proper choice of fabrication, high-quality devices are obtained....

  6. Pairs of dual periodic frames

    DEFF Research Database (Denmark)

    Christensen, Ole; Goh, Say Song

    2012-01-01

    is needed. The purpose of the present paper is to provide constructions of dual pairs of frames in the setting of the Hilbert space of periodic functions L2(0,2π). The frames constructed are given explicitly as trigonometric polynomials, which allows for an efficient calculation of the coefficients...

  7. Quasi-Periodic Spatiotemporal Filtering

    NARCIS (Netherlands)

    Burghouts, G.J.; Geusebroek, J.M.

    2006-01-01

    This paper presents the online estimation of temporal frequency to simultaneously detect and identify the quasi-periodic motion of an object. We introduce color to increase discriminative power of a reoccurring object and to provide robustness to appearance changes due to illumination changes. Spati

  8. Coupling light to periodic nanostructures

    NARCIS (Netherlands)

    Driessen, Eduard Frans Clemens

    2009-01-01

    This thesis describes coupling of light to periodic structures. A material is patterned with a regular pattern on a length scale comparable to the wavelength of light. With these structures, light can be manipulated very precisely. The structures find applications in semiconductor lasers, light emit

  9. Periodic progress report, 6 months

    DEFF Research Database (Denmark)

    Juhl, Thomas Winther; Nielsen, Jakob Skov

    This is the first progress report of the BriteEuram project named "High Power Laser Cutting for Heavy Industry" ("Powercut"). The report contains a summary of the objectives of the first period, an overview of the technical progress, a comparison between the planed and the accomplished work...

  10. Periodic solutions and slow manifolds

    NARCIS (Netherlands)

    Verhulst, F.

    2006-01-01

    After reviewing a number of results from geometric singular perturbation theory, we give an example of a theorem for periodic solutions in a slow manifold. This is illustrated by examples involving the van der Pol-equation and a modified logistic equation. Regarding nonhyperbolic transitions we disc

  11. Periodic progress report, 6 months

    DEFF Research Database (Denmark)

    Juhl, Thomas Winther; Nielsen, Jakob Skov

    This is the first progress report of the BriteEuram project named "High Power Laser Cutting for Heavy Industry" ("Powercut"). The report contains a summary of the objectives of the first period, an overview of the technical progress, a comparison between the planed and the accomplished work...

  12. Quantifying Periodicity in Omics Data

    Directory of Open Access Journals (Sweden)

    Cornelia eAmariei

    2014-08-01

    Full Text Available Oscillations play a significant role in biological systems, with many examples in the fast, ultradian, circadian, circalunar and yearly time domains. However, determining periodicity in such data can be problematic. There are a number of computational methods to identify the periodic components in large datasets, such as signal-to-noise based Fourier decomposition, Fisher's g-test and autocorrelation. However, the available methods assume a sinusoidal model and do not attempt to quantify the waveform shape and the presence of multiple periodicities, which provide vital clues in determining the underlying dynamics. Here, we developed a Fourier based measure that generates a de-noised waveform from multiple significant frequencies. This waveform is then correlated with the raw data from the respiratory oscillation found in yeast, to provide oscillation statistics including waveform metrics and multi-periods. The method is compared and contrasted to commonly used statistics. Moreover we show the utility of the program in the analysis of noisy datasets and other high-throughput analyses, such as metabolomics and flow cytometry, respectively.

  13. Glass Waveguides for Periodic Poling

    DEFF Research Database (Denmark)

    Fage-Pedersen, Jacob; Jacobsen, Rune Shim; Kristensen, Martin

    2005-01-01

    Planar silica-based waveguide devices have been developed for second-harmonic generation by poling with periodic electrodes. We show that detrimental charge transport can occur along interfaces, but with proper choice of fabrication, high-quality devices are obtained....

  14. Shanghai's Fashion During Republic Period

    Institute of Scientific and Technical Information of China (English)

    卞向阳

    2004-01-01

    The goal of this research is to describe and analyze Shanghai's fashion during Republic Period. Shanghai's fashion during Republic Period plays a special role in fashion history of China and Shanghai history. In the paper, three aspects including the fashion centre of China as well as Far East, men's fashion and women's fashion in Shanghai are discussed. The style, textiles, color, decoration and combination of clothing are described. Many costumes from the Clothing Museum at Donghua University and private collections as well as some historical writings, photographs and publications are elucidated and corroborated to give a more detailed description about Shanghai's fashion during that period.Here are some tentative conclusions. Firstly, Shanghai had always been the fashion center in China even Far East during Republic Period. Modeng was the main reflection of Shanghai fashion. Secondly, the traditional clothing exerted less influence and was less widely used, some kinds and combinations were out of fashion gradually. The fashion was described to be highly stylized, exquisite and concise. Thirdly, the influence of Western Style was further greater. The fashion in Shanghai was almost synchronous with fashion of Paris. Some western clothing was directly used in daily life and the elements of Western Style had an increasingly wide utilization. Fourthly, the New Chinese Style whose representatives were Qipao and Zhongshan Zhuang appeared and popularized in Shanghai. The fashion of Qipao changed frequently. Finally, the fashion in Shanghai called Shanghai Style could be summarized fashionable, exquisite, rapidly changeable, which is harmonious of both ancient and modern, Chinese and foreign.

  15. Soliton Management in Periodic Systems

    CERN Document Server

    Malomed, Boris A

    2006-01-01

    During the past ten years, there has been intensive development in theoretical and experimental research of solitons in periodic media. This book provides a unique and informative account of the state-of-the-art in the field. The volume opens with a review of the existence of robust solitary pulses in systems built as a periodic concatenation of very different elements. Among the most famous examples of this type of systems are the dispersion management in fiber-optic telecommunication links, and (more recently) photonic crystals. A number of other systems belonging to the same broad class of spatially periodic strongly inhomogeneous media (such as the split-step and tandem models) have recently been identified in nonlinear optics, and transmission of solitary pulses in them was investigated in detail. Similar soliton dynamics occurs in temporal-domain counterparts of such systems, where they are subject to strong time-periodic modulation (for instance, the Feshbach-resonance management in Bose-Einstein conde...

  16. System Optimization by Periodic Control.

    Science.gov (United States)

    1979-09-30

    extended re- sults are now contained in a single report [3] which will appear as a regular paper in the December, 1979 issue of the IEEE Transactions on Automatic Control . The...Test Revisited, " to appear in the IEEE Transactions on Automatic Control . 4. D. J. Lyons, "Improved Aircraft Cruise by Periodic Control," Ph. D

  17. 76 FR 80312 - Periodic Reporting

    Science.gov (United States)

    2011-12-23

    ... of the Business Reply Mail cost model in periodic reporting of service performance measurement... initiate a rulemaking proceeding to address the current methodology used to develop the avoided cost.... SUMMARY: The Commission is establishing a docket to consider new measurement of Flats Sequencing...

  18. Hyperkalemic periodic paralysis associated with multiple sleep onset REM periods.

    Science.gov (United States)

    Iranzo, A; Santamaria, J

    1999-12-15

    A 24-year-old man with sporadic hyperkalemic periodic paralysis (HPP) presented with moderate excessive daytime sleepiness and transitory episodes of weakness which occurred during and after sleep. Multiple sleep latency test (MSLT) demonstrated the presence of five sleep onset REM periods (SOREMPs) and a sleep latency of five minutes. Treatment with a diuretic which decreases serum potassium resolved all the clinical symtomps and a new MSLT showed the absence of SOREMPs and a sleep latency of 13.5 minutes. To our knowledge, the patient herein reported is the first case that associates sleep abnormalities and multiple SOREMPs with HPP. Furthermore, the present case suggests that SOREMPs may be explained by an increased extracellular potassium conductance related to HPP.

  19. Measurements and Application of Partition Coefficients of Compounds Suitable for Tracing Gas Injected Into Oil Reservoirs Mesures et applications des coefficients de partage de composants utilisables comme gaz traceurs injectés dans des réservoirs de pétrole

    Directory of Open Access Journals (Sweden)

    Dugstad O.

    2006-11-01

    Full Text Available Tracing of injection gas in oil reservoirs is a technique used to improve the description of permeability distributions in situ. Results from dynamic laboratory experiments of gas tracers are reported. Gas tracers are delayed when flooding through a reservoir by the partitioning into the oil phase. A knowledge of this effect is important to optimize the interpretation of field tracer tests. The partition is quantified by the partition coefficient K. Two chemical tracers perfluoromethylcyclopentane (PMCP and perfluoromethylcyclohexane (PMCH and the radioactive 14C labelled ethane have been studied here. The two chemical compounds are new as reservoir tracers and no field results with these tracers are reported in the open literature. Our group has, however, recently applied these compound successfully as tracers in a North Sea reservoir. Les traceurs représentent un outil précieux pour améliorer la description des gisements. On les a utilisés pour obtenir des renseignements sur la configuration de l'écoulement des fluides injectés et sur leur vitesse, sur l'instant de percé des venues d'eau et sur leur origine précise, sur les traitements d'amélioration du balayage, sur les hétérogénéités importantes telles que fractures, barrières d'écoulement et stratifications de la perméabilité. Dans les gisements importants comportant plusieurs puits de production et plusieurs puits d'injection, il est donc souhaitable de disposer de plusieurs traceurs afin de pouvoir injecter différents traceurs ou mélanges de traceurs dans les différents puits. L'article présenté ici est une contribution a l'effort fait pour étendre le nombre de gaz traceurs fiables applicables aux gisements. L'article présente les résultats d'essais dynamiques en laboratoires dans lesquels on injecte des traceurs à travers un milieu poreux. Lorsqu'ils traversent un réservoir, les gaz traceurs sont retardés du fait de leur ségrégation dans la phase huile. La

  20. 7 CFR 1160.113 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Fiscal period. 1160.113 Section 1160.113 Agriculture... Definitions § 1160.113 Fiscal period. Fiscal period means the initial period of up to 30 months that this subpart is effective. Thereafter, the fiscal period shall be such annual period as the Board may...

  1. Geopulsation, Volcanism and Astronomical Periods

    Institute of Scientific and Technical Information of China (English)

    Yang Xuexiang; Chen Dianyou; Yang Xiaoying; Yang Shuchen

    2000-01-01

    Volcanism is mainly controlled by the intermittent release of energy in the earth. As far as the differential rotation of the earth's inner core is concerned, the Galactic Year may change the gravitational constant G, the solar radiative quantity and the moving speed of the solar system and affect the exchange of angular momentum between core and mantle as well as the energy exchange between crust and mantle. As a result, this leads to eruptions of superplumes and magma, and controls the energy flow from core - mantle boundary (CMB) to crust. When the earth' s speed decreases, it will release a huge amount of energy. They are the reason of the correspondence of the volcanic cycles one by one with the astronomical periods one by one. According to the astronomical periods, volcanic eruptions may possibly be predicted in the future.

  2. Fibromyalgia in hyperkalemic periodic paralysis.

    Science.gov (United States)

    Götze, F R; Thid, S; Kyllerman, M

    1998-01-01

    A 43-year-old woman presented at the age of 38 with joint pains and muscle stiffness. Tender points were found fulfilling ACR criteria (1) for fibromyalgia. She had well developed muscles and decreasing muscle power since the age of 35. Muscle pains increased after exercise. Her 10-year-old son had similar symptoms and one paralytic attack. Muscle pain and fatigue increasing with age were found by history in three close relatives. Forearm cold water test produced myotonia in both mother and son. Electromyography was normal and muscle biopsy showed minor unspecific changes. Biochemical investigation of muscle mitochondrial function was normal. Peroral potassium load test produced complete muscle paralysis at a potassium serum level of 5.0 mmol/l. Autosomal dominant hyperkalemic periodic paralysis was diagnosed. Frequent carbohydrate enriched meals, peroral bendroflumethiazide and restriction to submaximal exercise improved muscle and joint pain. Salbutamol peroral spray relieved the periodic weakness.

  3. Exploration of Periodically Varying Graphs

    CERN Document Server

    Flocchini, Paola; Santoro, Nicola

    2009-01-01

    We study the computability and complexity of the exploration problem in a class of highly dynamic graphs: periodically varying (PV) graphs, where the edges exist only at some (unknown) times defined by the periodic movements of carriers. These graphs naturally model highly dynamic infrastructure-less networks such as public transports with fixed timetables, low earth orbiting (LEO) satellite systems, security guards' tours, etc. We establish necessary conditions for the problem to be solved. We also derive lower bounds on the amount of time required in general, as well as for the PV graphs defined by restricted classes of carriers movements: simple routes, and circular routes. We then prove that the limitations on computability and complexity we have established are indeed tight. In fact we prove that all necessary conditions are also sufficient and all lower bounds on costs are tight. We do so constructively presenting two worst case optimal solution algorithms, one for anonymous systems, and one for those w...

  4. Social Research On Renaissance Period

    Institute of Scientific and Technical Information of China (English)

    张蕾蕾

    2009-01-01

    The historical period known as the Renaissance spans the fifteenth and siXteenth centuries. ‘Renaissance'means‘re-birth'in French and during this time Europe left behind the mindset of the Midge Ages and created the beginnings of the modern world.This thesis mainly rotates on the background,the main features and significance of Renaissance,especially focuses on the discovery of man and the humanism and the detailed unfolding of the society on several aspect in Renaissance.

  5. Periodic Convergences: Dance and Computers

    OpenAIRE

    deLahunta, Scott

    2002-01-01

    Published in German and English, this chapter is one of deLahunta's major outputs to emerge from a group of related research outputs, concerning "dance and technology". In it he explores the history of the convergence between dance and computers from the 1960s to the 1990s, arguing that this convergence has been periodic, involving particular artists at particular times, rather than producing a genre of work (as others have speculated). As the mainstream of contemporary dance evolved alongsid...

  6. Periodic Structures in Optical Fibres.

    Science.gov (United States)

    Hand, Duncan Paul

    1990-01-01

    Available from UMI in association with The British Library. The work presented in this thesis concerns techniques for the formation of periodic structures in optical fibres. Two different methods of producing such structures are studied in detail. The first of these involves a breakdown mechanism (known as the 'fibre fuse') that permanently damages the core glass in a periodic manner leaving it unable to guide light. The dynamics of this mechanism are studied, with a view to controlling it for the production of interactive grating structures. It is determined that, due to a sharp rise in fibre absorption with temperature, a thermal shock -wave, with a typical thermal gradient of several hundred degrees Kelvin per micron, forms and travels along the fibre, heating the core glass to such an extent that damage occurs. The periodicity of the resultant damage arises from thermal focusing and defocusing of light in the region of this shock-wave. The second method makes use of the photorefractivity observed in certain germanosilicate fibres on exposure to moderate intensity blue light of wavelength ~480nm or UV light ~240nm. A single-mode fibre transmission filter is demonstrated for the first time, produced by exposing a fibre Sagnac loop mirror to 488nm holographic fringes. Average index changes are shown to occur if such fibres are exposed to spatially uniform blue or UV light, indicating that grating formation is by a different mechanism to the local charge separation which occurs in photorefractive crystals. The various characteristics of these average index changes are measured and analysed, with the conclusion that they result from defect centre formation, driven by two photon absorption with blue light, or single photon absorption with UV light. Associated birefringence changes are also measured and are exploited in a hi-bi fibre to periodically perturb the birefringence axes, producing a narrow-line transmission filter.

  7. Regular and Periodic Tachyon Kinks

    OpenAIRE

    Bazeia, D.; Menezes, R.; Ramos, J. G.

    2004-01-01

    We search for regular tachyon kinks in an extended model, which includes the tachyon action recently proposed to describe the tachyon field. The extended model that we propose adds a new contribution to the tachyon action, and seems to enrich the present scenario for the tachyon field. We have found stable tachyon kinks of regular profile, which may appropriately lead to the singular kink found by Sen sometime ago. Also, under specific conditions we may find periodic array of kink-antikink co...

  8. Constituents of Doubly Periodic Instantons

    CERN Document Server

    Ford, C; Ford, Chris; Pawlowski, Jan M.

    2002-01-01

    Using the Nahm transform we investigate doubly periodic charge one SU(2) instantons with radial symmetry. Two special points where the Nahm zero modes have softer singularities are identified as constituent locations. To support this picture, the action density is computed analytically and numerically within a two dimensional slice containing the two constituents. For particular values of the parameters the torus can be cut in half yielding two copies of a twisted charge 1/2 instanton. Such objects comprise a single constituent.

  9. 76 FR 78246 - Extension of the Extended Missing Parts Pilot Program

    Science.gov (United States)

    2011-12-16

    ... Time Period To Reply to a Notice to File Missing Parts of Nonprovisional Application, 75 FR 76401 (Dec...), 74 FR 55200 (Oct. 27, 2009), 1348 Off. Gaz. Pat. Office 394 (Nov. 24, 2009). II. Processing of... Parts of Nonprovisional Application, 75 FR 76401, 76403-04 (Dec. 8, 2010), 1362 Off. Gaz. Pat. Office...

  10. Forgiveness in the intertestamental period

    Directory of Open Access Journals (Sweden)

    Sang-Mong Lee

    2012-02-01

    Full Text Available The article suggests answers to the following questions: what are the characteristics of God�s forgiveness in the intertestamental literature and what connection do these characteristics have with the Old Testament? Important passages in the late Second Temple period that expose the characteristics of God�s forgiveness, such as certain Qumran texts (1QH 12:35�37, 1QH 13:2 and the Damascus Document 14:18�19, the writings of Philo and Josephus, the Apocrypha and the Pseudepigrapha, are investigated for this purpose.

  11. Periodic roads and quantized wheels

    Science.gov (United States)

    de Campos Valadares, Eduardo

    2016-08-01

    We propose a simple approach to determine all possible wheels that can roll smoothly without slipping on a periodic roadbed, while maintaining the center of mass at a fixed height. We also address the inverse problem that of obtaining the roadbed profile compatible with a specific wheel and all other related "quantized wheels." The role of symmetry is highlighted, which might preclude the center of mass from remaining at a fixed height. A straightforward consequence of such geometric quantization is that the gravitational potential energy and the moment of inertia are discrete, suggesting a parallelism between macroscopic wheels and nano-systems, such as carbon nanotubes.

  12. La fonction logistique, un outil performant d'analyse et de prévision à moyen terme. Application à la production de pétrole et de gaz aux Etats-Unis, en URSS et dans d'autres pays The Logistic Function, an Efficient Medium-Range Analysis and Forecasting Method

    Directory of Open Access Journals (Sweden)

    Seguret J.

    2006-11-01

    Full Text Available A partir de la similitude observée entre l'évolution de la production pétrolière d'un pays et celle de la pénétration d'un produit dans un marché (fonction logistique, l'auteur expose le principe d'une méthode originale qui permet, sous certaines conditions, de prévoir quelle sera la production annuelle probable d'un pays producteur à un horizon de 10 à 15 ans. La validité de cette méthode est d'abord démontrée sur l'exemple de la production pétrolière aux Etats-Unis. Elle est ensuite illustrée par les résultats obtenus pour un certain nombre de pays : production future de gaz aux Etats-Unis, production pétrolière future du Canada, de l'URSS, du Venezuela et de l'ensemble du monde hors Moyen-Orient. On the basis of the similarity observed between the variation in the petroleum production of a country and that of the penetration of a product into the market (logistic function, this article describes the principle of an original method that can be used, under certain conditions, to forecast the probable annual production of a producing country in 10 to 15 years. The validity of this method is first demonstrated for the example of oil production in the United States. It is then illustrated by results obtained for various other countries, i. e. future gas production in the United States, future oil production of Canada, the Soviet Union, Venezuela and the world as a whole outside of the Middle East.

  13. 7 CFR 955.113 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 955.113 Section 955.113 Agriculture... and Regulations § 955.113 Fiscal period. Pursuant to § 955.13, fiscal period shall mean the period beginning January 1 and ending December 31 of each year, except that the fiscal period that began...

  14. 7 CFR 929.106 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 929.106 Section 929.106 Agriculture... LONG ISLAND IN THE STATE OF NEW YORK Rules and Regulations § 929.106 Fiscal period. The fiscal period... include the period of August 1, through August 31, 1968. Thereafter, the fiscal period will begin...

  15. 44 CFR 206.112 - Registration period.

    Science.gov (United States)

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Registration period. 206.112... Households § 206.112 Registration period. (a) Initial period. The standard FEMA registration period is 60...) Extension of the registration period. The regional administrator or his/her designee may extend the...

  16. 7 CFR 920.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 920.7 Section 920.7 Agriculture... Definitions § 920.7 Fiscal period. Fiscal period is synonymous with fiscal year and means a 12-month period... period as the committee, with the approval of the Secretary, may prescribe. ...

  17. 7 CFR 955.13 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 955.13 Section 955.13 Agriculture... Definitions § 955.13 Fiscal period. Fiscal period means the 12-month period beginning on September 16 and ending on September 15 of the next year or such other period that may be recommended by the committee and...

  18. 7 CFR 930.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 930.7 Section 930.7 Agriculture... Definitions § 930.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period beginning on July 1 of any year and ending on June 30 of the following year, or such other period as the...

  19. A periodic table for cancer.

    Science.gov (United States)

    Epstein, Richard J

    2015-01-01

    Cancers exhibit differences in metastatic behavior and drug sensitivity that correlate with certain tumor-specific variables such as differentiation grade, growth rate/extent and molecular regulatory aberrations. In practice, patient management is based on the past results of clinical trials adjusted for these biomarkers. Here, it is proposed that treatment strategies could be fine-tuned upfront simply by quantifying tumorigenic spatial (cell growth) and temporal (genetic stability) control losses, as predicted by genetic defects of cell-cycle-regulatory gatekeeper and genome-stabilizing caretaker tumor suppressor genes, respectively. These differential quantifications of tumor dysfunction may in turn be used to create a tumor-specific 'periodic table' that guides rational formulation of survival-enhancing anticancer treatment strategies.

  20. Quasi Periodic Oscillations in Blazars

    Indian Academy of Sciences (India)

    Alok C. Gupta

    2014-09-01

    Here we report our recent discoveries of Quasi-Periodic Oscillations (QPOs) in blazars time series data in X-ray and optical electromagnetic bands. Any such detection can give important clues of the location and nature of the processes of emission mechanism. In the case of radio-quiet AGN, the detected QPOs are very likely to be associated with the accretion disk. But in the case of blazars, it may be associated with jets in the high and outburst states, and in the low-state, it is probably associated with the accretion disk. In this brief review, I summarize the recent QPO detections in blazars. There is one strong evidence of QPO detection in XMM–Newton time series data of narrow line Seyfert 1 galaxy RE J1034+396 about which we will also discuss briefly.

  1. A model for periodic blazars

    CERN Document Server

    Sobacchi, Emanuele; Stamerra, Antonio

    2016-01-01

    We describe a scenario to explain blazar periodicities with timescales of $\\sim$ few years. The scenario is based on a binary super-massive black hole (SMBH) system in which one of the two SMBH carries a jet. We discuss the various mechanisms that can cause the jet to precess and produce corkscrew patterns through space with a scale of $\\sim$ few pc. It turns out that the dominant mechanism responsible for the precession is simply the imprint of the jet-carrying SMBH orbital speed on the jet. Gravitational deflection and Lense-Thirring precession (due to the gravitational field of the other SMBH) are second order effects. We complement the scenario with a kinematical jet model which is inspired to the spine-sheath structure observed in M87. One of the main advantages of such a structure is that it allows the peak of the synchrotron emission to scale with frequency according to $\

  2. Time—periodic weak solutions

    Directory of Open Access Journals (Sweden)

    Eliana Henriques de Brito

    1990-01-01

    Full Text Available In continuing from previous papers, where we studied the existence and uniqueness of the global solution and its asymptotic behavior as time t goes to infinity, we now search for a time-periodic weak solution u(t for the equation whose weak formulation in a Hilbert space H isddt(u′,v+δ(u′,v+αb(u,v+βa(u,v+(G(u,v=(h,vwhere: ′=d/dt; (′ is the inner product in H; b(u,v, a(u,v are given forms on subspaces U⊂W, respectively, of H; δ>0, α≥0, β≥0 are constants and α+β>0; G is the Gateaux derivative of a convex functional J:V⊂H→[0,∞ for V=U, when α>0 and V=W when α=0, hence β>0; v is a test function in V; h is a given function of t with values in H.

  3. 7 CFR 953.122 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 953.122 Section 953.122 Agriculture... STATES Rules and Regulations Change in Date for Completing Nominations, Term of Office, and Fiscal Period § 953.122 Fiscal period. The fiscal period, pursuant to § 953.9, which began on April 1, 1976, shall...

  4. 7 CFR 947.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 947.9 Section 947.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Definitions § 947.9 Fiscal period. Fiscal period means the period beginning and ending on the dates...

  5. 7 CFR 923.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 923.7 Section 923.7 Agriculture... COUNTIES IN WASHINGTON Order Regulating Handling Definitions § 923.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on March 31 of each year or such...

  6. 7 CFR 966.16 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 966.16 Section 966.16 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 966.16 Fiscal period. Fiscal period means the period beginning August 1...

  7. 7 CFR 948.10 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 948.10 Section 948.10 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Definitions § 948.10 Fiscal period. Fiscal period means the period...

  8. 7 CFR 922.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 922.7 Section 922.7 Agriculture... IN WASHINGTON Order Regulating Handling Definitions § 922.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on March 31 of each year or such...

  9. 7 CFR 1221.10 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1221.10 Section 1221.10 Agriculture... INFORMATION ORDER Sorghum Promotion, Research, and Information Order Definitions § 1221.10 Fiscal period. Fiscal period means the 12-month period ending on December 31 or such other consecutive 12-month...

  10. 7 CFR 1230.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1230.9 Section 1230.9 Agriculture... CONSUMER INFORMATION Pork Promotion, Research, and Consumer Information Order Definitions § 1230.9 Fiscal period. Fiscal period means the 12-month period ending on December 31 or such other consecutive...

  11. 7 CFR 1220.111 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1220.111 Section 1220.111 Agriculture... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.111 Fiscal period. The term fiscal period means the calendar year or such other annual period as the Board may determine with...

  12. 7 CFR 924.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 924.7 Section 924.7 Agriculture... COUNTIES IN WASHINGTON AND IN UMATILLA COUNTY, OREGON Order Regulating Handling Definitions § 924.7 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on March 31...

  13. 7 CFR 948.103 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 948.103 Section 948.103 Agriculture... Rules and Regulations General § 948.103 Fiscal period. Pursuant to § 948.10, the fiscal periods for each... following year, both dates inclusive. The 1986-87 fiscal period which began July 1, 1986, will be...

  14. 7 CFR 946.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 946.9 Section 946.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Definitions § 946.9 Fiscal period. Fiscal period means the period beginning...

  15. 7 CFR 1218.8 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1218.8 Section 1218.8 Agriculture... INFORMATION ORDER Blueberry Promotion, Research, and Information Order Definitions § 1218.8 Fiscal period. Fiscal period means a calendar year from January 1 through December 31, or such other period as...

  16. 7 CFR 929.6 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 929.6 Section 929.6 Agriculture... LONG ISLAND IN THE STATE OF NEW YORK Order Regulating Handling Definitions § 929.6 Fiscal period. Fiscal period is synonymous with fiscal year and crop year and means the 12-month period...

  17. 7 CFR 956.113 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 956.113 Section 956.113 Agriculture... VALLEY OF SOUTHEAST WASHINGTON AND NORTHEAST OREGON Rules and Regulations § 956.113 Fiscal period. Pursuant to § 956.13, fiscal period shall mean the period beginning January 1 and ending December 31...

  18. 7 CFR 927.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 927.9 Section 927.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Regulating Handling Definitions § 927.9 Fiscal period. Fiscal period means the period...

  19. 7 CFR 959.16 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 959.16 Section 959.16 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 959.16 Fiscal period. Fiscal period means the annual period beginning...

  20. 7 CFR 917.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 917.9 Section 917.9 Agriculture... CALIFORNIA Order Regulating Handling Definitions § 917.9 Fiscal period. Fiscal period is synonymous with fiscal year and means the 12-month period ending on the last day of February of each year, or such...

  1. 7 CFR 945.12 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 945.12 Section 945.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Fiscal period. Fiscal period means the period beginning and ending on the dates approved by the...

  2. 7 CFR 958.12 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 958.12 Section 958.12 Agriculture... COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Order Regulating Handling Definitions § 958.12 Fiscal period. Fiscal period means the period beginning and ending on the dates approved by the Secretary pursuant...

  3. 30 CFR 887.13 - Grant period.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Grant period. 887.13 Section 887.13 Mineral... LAND RECLAMATION SUBSIDENCE INSURANCE PROGRAM GRANTS § 887.13 Grant period. The grant funding period... remaining at the end of any grant period to us according to 43 CFR part 12. ...

  4. 7 CFR 1280.611 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1280.611 Section 1280.611... INFORMATION ORDER Procedures To Request a Referendum Definitions § 1280.611 Representative period. Representative period means the period designated by the Secretary pursuant to § 518 of the Act. ...

  5. 42 CFR 413.239 - Transition period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Transition period. 413.239 Section 413.239 Public...) Services and Organ Procurement Costs § 413.239 Transition period. (a) Duration of transition period and... § 413.171, furnished during the transition period, new ESRD facilities as defined in § 413.171, are paid...

  6. 5 CFR 351.801 - Notice period.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Notice period. 351.801 Section 351.801... Employee § 351.801 Notice period. (a)(1) Each competing employee selected for release from a competitive... or designee, may approve a notice period of less than 60 days. The shortened notice period must cover...

  7. 7 CFR 1230.621 - Voting period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Voting period. 1230.621 Section 1230.621 Agriculture... CONSUMER INFORMATION Procedures for the Conduct of Referendum Definitions § 1230.621 Voting period. The term Voting period means the 3-consecutive business day period for in-person voting. Referendum ...

  8. 42 CFR 412.426 - Transition period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Transition period. 412.426 Section 412.426 Public... Services of Inpatient Psychiatric Facilities § 412.426 Transition period. (a) Duration of transition period..., for cost reporting periods beginning on or after January 1, 2005 through January 1, 2008, an inpatient...

  9. 7 CFR 1220.612 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1220.612 Section 1220.612... CONSUMER INFORMATION Procedures To Request a Referendum Definitions § 1220.612 Representative period. Representative period means the period designated by the Secretary pursuant to section 1970 of the Act. ...

  10. 20 CFR 627.901 - Transition period.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Transition period. 627.901 Section 627.901... PROGRAMS UNDER TITLES I, II, AND III OF THE ACT Transition Provisions § 627.901 Transition period. The transition period ended June 30, 1993 unless otherwise stated. The intent of the transition period is to...

  11. 42 CFR 413.340 - Transition period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Transition period. 413.340 Section 413.340 Public... Facilities § 413.340 Transition period. (a) Duration of transition period and proportions for the blended transition rate. Beginning with an SNF's first cost reporting period beginning on or after July 1, 1998...

  12. 9 CFR 2.101 - Holding period.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Holding period. 2.101 Section 2.101... WELFARE REGULATIONS Compliance With Standards and Holding Period § 2.101 Holding period. (a) Any live dog... and control, for a period of not less than 5 full days, not including the day of acquisition, after...

  13. 7 CFR 1280.613 - Voting period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Voting period. 1280.613 Section 1280.613 Agriculture... INFORMATION ORDER Procedures To Request a Referendum Definitions § 1280.613 Voting period. The term voting period means a 4-week period to be announced by the Secretary for voting the referendum. Procedures ...

  14. 42 CFR 412.626 - Transition period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Transition period. 412.626 Section 412.626 Public... Hospitals and Rehabilitation Units § 412.626 Transition period. (a) Duration of transition period and... (b) of this section, for cost reporting periods beginning on or after January 1, 2002 and before...

  15. Time evolutions of the greenhouse effect gases concentration and the climate from the Vostok core; Evolutions temporelles de la concentration en gaz a effet de serre et du climat d'apres la carotte de Vostok (Antarctique)

    Energy Technology Data Exchange (ETDEWEB)

    Pepin, L.; Barnola, J.M.; Petit, J.R.; Raynaud, D. [CNRS, Lab. de Glaciologie et de Geophysique de l' Environnement, Universite Joseph-Fourier, Grenoble I, 38 (France)

    2000-07-01

    Polar ice and air bubbles trapped in it, attest climate history and the atmospheric composition of the Earth. The Vostok drill at the Russian station of Vostok on the Antarctic Plateau provides a more 400 000-year long record of these conditions. Though this time, climate in Antarctica oscillated between 4 glacials, for which surface temperatures were about 10 deg C below modern ones, and 5 interglacial periods as the modern one. It is shown that greenhouse gases (CO{sub 2} and CH{sub 4}) concentrations are higher during warm periods than cold ones. Scrutinizing glacial to interglacial transitions shows that Southern Hemisphere processes lead northern ones. Furthermore, sea level rise appears to lag variations of other variables. Finally, these records give evidence that CO{sub 2} and CH{sub 4} levels measured at present time, have never been reached during the late 420 000 years. (authors)

  16. Periodic solutions of nonlinear vibrating beams

    Directory of Open Access Journals (Sweden)

    J. Berkovits

    2003-01-01

    Full Text Available The aim of this paper is to prove new existence and multiplicity results for periodic semilinear beam equation with a nonlinear time-independent perturbation in case the period is not prescribed. Since the spectrum of the linear part varies with the period, the solvability of the equation depends crucially on the period which can be chosen as a free parameter. Since the period of the external forcing is generally unknown a priori, we consider the following natural problem. For a given time-independent nonlinearity, find periods T for which the equation is solvable for any T-periodic forcing. We will also deal with the existence of multiple solutions when the nonlinearity interacts with the spectrum of the linear part. We show that under certain conditions multiple solutions do exist for any small forcing term with suitable period T. The results are obtained via generalized Leray-Schauder degree and reductions to invariant subspaces.

  17. 7 CFR 1205.20 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1205.20 Section 1205.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... period means the 2006 calendar year....

  18. Periodic Control of Power Electronic Converters

    DEFF Research Database (Denmark)

    Zhou, Keliang; Danwei, Wang; Yang, Yongheng

    Advanced power electronic converters convert, control and condition electricity. Power converters require control strategies for periodic signal compensation to assure good power quality and stable power system operation. This comprehensive text presents the most recent internal model principle...... based periodic control technology, which offers the perfect periodic control solution for power electronic conversion. It also provides complete analysis and synthesis methods for periodic control systems, and plenty of practical examples to demonstrate the validity of proposed periodic control...... technology for power converters. It proposes a unified framework for housing periodic control schemes for power converters, and provides a general proportional-integral-derivative control solution to periodic signal compensation in extensive engineering applications. Periodic Control of Power Electronic...

  19. US Forest Service Periodical Cicada Broods

    Data.gov (United States)

    US Forest Service, Department of Agriculture — A map service on the www depicting periodical cicada distribution and expected year of emergence by cicada brood and county. The periodical cicada emerges in massive...

  20. Periodic Solution of the Hematopoiesis Equation

    Directory of Open Access Journals (Sweden)

    Ji-Huan He

    2013-01-01

    Full Text Available Wu and Liu (2012 presented some results for the existence and uniqueness of the periodic solutions for the hematopoiesis model. This paper gives a simple approach to find an approximate period of the model.

  1. Inventory of greenhouse effect gases in France under the united nation framework convention on climatic change; Inventaire des emissions de gaz a effet de serre en France au titre de la convention cadre des nations unies sur le changement climatique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-12-01

    The present report supplies emission data, for France and for the period 1990 - 2000 concerning all the substances involved in the increase in the greenhouse effect and covered under the United Nations' Framework Convention on Climate Change (UNFCCC). The substances are the six direct greenhouse gases covered by the Kyoto protocol: carbon dioxide (CO{sub 2}), methane (CH{sub 4}), nitrous oxide (N{sub 2}O), the two species of halogenous substances - hydro-fluorocarbons (HFCs) and per-fluorocarbons (PFCs), and sulphur hexafluoride (SF{sub 6}). Emissions of sulphur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), non methane volatile organic compounds (NMVOCs), and carbon monoxide (CO), gases which indirectly make a significant contribution to the greenhouse effect, are reported under the Convention. For the period 1990 - 1999 as a whole, estimates provided in the previous inventories have been reviewed and corrected to take into account updated statistics, improved knowledge, possible changes in methodology and specifications contained in the guidelines (FCCC/CP/1999/7) defined by the UNFCCC on reporting for inventories of emissions, in particular the use of the Common Reporting Format (CRF). (author)

  2. The Middle Islamic and Crusader Periods

    DEFF Research Database (Denmark)

    Walmsley, Alan George

    2008-01-01

    The book chapter presents a critical review of the archaeology of Jordan in the middle Islamic periods (8th - 17th centuries CE), presenting a new evaluation of settlement and culture in the period, and assesses the errors of past appraoches.......The book chapter presents a critical review of the archaeology of Jordan in the middle Islamic periods (8th - 17th centuries CE), presenting a new evaluation of settlement and culture in the period, and assesses the errors of past appraoches....

  3. Prediction Theory of Periodically Correlated Stochastic Processes

    Science.gov (United States)

    2015-05-12

    in order to do a reliable forecasting of periodically correlated sequences with large period (or continuous time processes) the standard method of...aimed at sequences with large periods. It has been known already for years that in order to do a reliable forecasting of periodically correlated...we showed that this technique is very efficient. We successfully used it to study structure, regularity, autoregressive representation, innovation

  4. 19 CFR 114.23 - Maximum period.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Maximum period. 114.23 Section 114.23 Customs... CARNETS Processing of Carnets § 114.23 Maximum period. (a) A.T.A. carnet. No A.T.A. carnet with a period of validity exceeding 1 year from date of issue shall be accepted. This period of validity cannot be...

  5. The period functions' higher order derivatives

    CERN Document Server

    Sabatini, Marco

    2012-01-01

    We prove a formula for the $n$-th derivative of the period function $T$ in a period annulus of a planar differential system. For $n = 1$, we obtain Freire, Gasull and Guillamon formula for the period's first derivative \\cite{FGG}. We apply such a result to hamiltonian systems with separable variables and other systems. We give some sufficient conditions for the period function of conservative second order O.D.E.'s to be convex.

  6. 12 CFR 561.6 - Audit period.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Audit period. 561.6 Section 561.6 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY DEFINITIONS FOR REGULATIONS AFFECTING ALL SAVINGS ASSOCIATIONS § 561.6 Audit period. The audit period of a savings association means the...

  7. 14 CFR 325.6 - Periodic reviews.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Periodic reviews. 325.6 Section 325.6... REGULATIONS ESSENTIAL AIR SERVICE PROCEDURES § 325.6 Periodic reviews. (a) The Department will start a periodic review of essential air service within 1 year of the date of the previous determination of...

  8. 7 CFR 945.111 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 945.111 Section 945.111 Agriculture... DESIGNATED COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Rules and Regulations Definitions § 945.111 Fiscal period. The fiscal period that began June 1, 1981, shall end July 31, 1982. Each year thereafter...

  9. 7 CFR 947.114 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 947.114 Section 947.114 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Definitions § 947.114 Fiscal period. The fiscal period shall begin July 1 of each year and end June 30 of...

  10. 7 CFR 905.11 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 905.11 Section 905.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... TANGELOS GROWN IN FLORIDA Order Regulating Handling Definitions § 905.11 Fiscal period. Fiscal period...

  11. 7 CFR 1205.307 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1205.307 Section 1205.307 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Research and Promotion Order Definitions § 1205.307 Fiscal period. Fiscal period is the 12-month...

  12. 7 CFR 1150.107 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Fiscal period. 1150.107 Section 1150.107 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Order Definitions § 1150.107 Fiscal period. Fiscal period means the calendar year or such other...

  13. 7 CFR 959.104 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 959.104 Section 959.104 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulations General § 959.104 Fiscal period. The fiscal period shall begin August 1 of each year and end...

  14. 7 CFR 930.107 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 930.107 Section 930.107 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Miscellaneous Provisions § 930.107 Fiscal period. Pursuant to § 930.7, fiscal period shall mean the...

  15. 7 CFR 916.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 916.7 Section 916.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 916.7 Fiscal period. Fiscal period is synonymous with fiscal year and...

  16. 7 CFR 925.12 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 925.12 Section 925.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... SOUTHEASTERN CALIFORNIA Definitions § 925.12 Fiscal period. Fiscal period is synonymous with fiscal year...

  17. 7 CFR 1250.303 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1250.303 Section 1250.303 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... Research and Promotion Order Definitions § 1250.303 Fiscal period. Fiscal period means the calendar...

  18. 7 CFR 953.9 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 953.9 Section 953.9 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... STATES Order Regulating Handling Definitions § 953.9 Fiscal period. Fiscal period means the...

  19. Generalized periodic and generalized Boolean rings

    Directory of Open Access Journals (Sweden)

    Howard E. Bell

    2001-01-01

    Full Text Available We prove that a generalized periodic, as well as a generalized Boolean, ring is either commutative or periodic. We also prove that a generalized Boolean ring with central idempotents must be nil or commutative. We further consider conditions which imply the commutativity of a generalized periodic, or a generalized Boolean, ring.

  20. CICATRIZATION OF WOUNDS : XI. LATENT PERIOD.

    Science.gov (United States)

    Carrel, A; du Noüy, P L

    1921-09-30

    1. The latent period of cicatrization varies generally from 5 to 7 days. 2. It stops abruptly and contraction starts with its maximum velocity. 3. The formula of du Noüy applies to the beginning of the contraction period as well as to the subsequent periods.

  1. 32 CFR 37.1325 - Periodic audit.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Periodic audit. 37.1325 Section 37.1325 National... TECHNOLOGY INVESTMENT AGREEMENTS Definitions of Terms Used in This Part § 37.1325 Periodic audit. An audit of... awards. Appendix C to this part describes what such an audit may cover. A periodic audit of a...

  2. 10 CFR 603.1295 - Periodic audit.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Periodic audit. 603.1295 Section 603.1295 Energy... Used in this Part § 603.1295 Periodic audit. An audit of a participant, performed at an agreed-upon... an audit may cover. A periodic audit of a participant differs from an award-specific audit of...

  3. 5 CFR 9901.411 - Appraisal period.

    Science.gov (United States)

    2010-01-01

    ....411 Administrative Personnel DEPARTMENT OF DEFENSE HUMAN RESOURCES MANAGEMENT AND LABOR RELATIONS... PERSONNEL SYSTEM (NSPS) Performance Management § 9901.411 Appraisal period. (a) Except as provided in... period, an employee has not met the minimum period of performance, management may extend the...

  4. 47 CFR 27.13 - License period.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false License period. 27.13 Section 27.13... COMMUNICATIONS SERVICES Applications and Licenses § 27.13 License period. (a) 2305-2320 MHz and 2345-2360 MHz... beyond the end of the license term if no broadcast service had been provided, whichever period is...

  5. 47 CFR 78.29 - License period.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false License period. 78.29 Section 78.29... SERVICE Applications and Licenses § 78.29 License period. Licenses for CARS stations will be issued for a period not to exceed five (5) years. On and after February 1, 1966, licenses for CARS stations...

  6. 47 CFR 5.71 - License period.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false License period. 5.71 Section 5.71...) Applications and Licenses § 5.71 License period. (a) The regular license period for stations in the Experimental Radio Service is either 2 or 5 years. An applicant desiring to apply for a 5-year license...

  7. Local Extrema of Periodic Function's Wavelet Transform

    Institute of Scientific and Technical Information of China (English)

    FAN Qi-bin; SONG Xiao-yan

    2005-01-01

    The theory of detecting ridges in the modulus of the continuous wavelet transform is presented as well as reconstructing signal by using information on ridges. To periodic signal we suppose Morlet wavelet as basic wavelet, and research the local extreme point and extrema of the wavelet transform on periodic function for the collection of signal's instantaneous amplitude and period.

  8. Cepheids : the period-luminosity relation

    NARCIS (Netherlands)

    Beaulieu, JP

    1997-01-01

    The Cepheids are relatively young, bright, periodic supergiant variable stars showing a correlation between their periods and luminosities. Since the beginning of the century, the Cepheid Period-Luminosity relation has been the corner stone of distance determination, and of the measure of the correl

  9. 47 CFR 22.1035 - Construction period.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Construction period. 22.1035 Section 22.1035 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Offshore Radiotelephone Service § 22.1035 Construction period. The construction period (see § 22.142) for...

  10. 5 CFR 317.503 - Probationary period.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Probationary period. 317.503 Section 317... THE SENIOR EXECUTIVE SERVICE Career Appointments § 317.503 Probationary period. (a) An individual's... probationary period as a career appointee; there has been an assessment of the appointee's performance during...

  11. 42 CFR 136a.31 - Transition period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Transition period. 136a.31 Section 136a.31 Public... OF HEALTH AND HUMAN SERVICES INDIAN HEALTH Transition Provisions § 136a.31 Transition period. (a) The transition period for full implementation of the new eligibility regulations consists of three parts; (1) A...

  12. 40 CFR 46.195 - Project period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Project period. 46.195 Section 46.195... During the Fellowship § 46.195 Project period. Based on the “Date Fellow Will Enter on Duty” which you enter on the Activation Notice (see § 46.185(a)), EPA will establish the project period for the...

  13. 5 CFR 2.4 - Probationary period.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Probationary period. 2.4 Section 2.4... SYSTEM (RULE II) § 2.4 Probationary period. Persons selected from registers of eligibles for career or... time, to supervisory or managerial positions shall be required to serve a probationary period under...

  14. 40 CFR 35.508 - Funding period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Funding period. 35.508 Section 35.508... ASSISTANCE Environmental Program Grants for Tribes Preparing An Application § 35.508 Funding period. The Regional Administrator and applicant may negotiate the length of the funding period for environmental...

  15. 47 CFR 73.7005 - Holding period.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Holding period. 73.7005 Section 73.7005... Applications for Noncommercial Educational Stations on Non-Reserved Channels § 73.7005 Holding period. (a... holding period. From the grant of the construction permit and continuing until the facility has achieved...

  16. 42 CFR 1008.3 - Effective period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 5 2010-10-01 2010-10-01 false Effective period. 1008.3 Section 1008.3 Public... ADVISORY OPINIONS BY THE OIG General Provisions § 1008.3 Effective period. The provisions in this part are..., 2000, and to any requests submitted during any other time period for which the OIG is required by law...

  17. 34 CFR 668.4 - Payment period.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Payment period. 668.4 Section 668.4 Education..., DEPARTMENT OF EDUCATION STUDENT ASSISTANCE GENERAL PROVISIONS General § 668.4 Payment period. (a) Payment periods for an eligible program that measures progress in credit hours and uses standard terms or...

  18. 5 CFR 316.304 - Trial period.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Trial period. 316.304 Section 316.304... Term Employment § 316.304 Trial period. (a) The first year of service of a term employee is a trial period regardless of the method of appointment. Prior Federal civilian service is credited toward...

  19. 29 CFR 548.405 - Representative period.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Representative period. 548.405 Section 548.405 Labor... Application § 548.405 Representative period. (a) The application must set forth the facts relied upon to show... employee exclusive of overtime premiums over a representative period of time. 21 The basic rate will be...

  20. 7 CFR 1230.618 - Representative period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Representative period. 1230.618 Section 1230.618... CONSUMER INFORMATION Procedures for the Conduct of Referendum Definitions § 1230.618 Representative period. The term Representative period means the 12-consecutive months prior to the first day of absentee and...

  1. 20 CFR 655.205 - Recruitment period.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Recruitment period. 655.205 Section 655.205... Agricultural Employment § 655.205 Recruitment period. (a) If the OFLC Administrator determines that the... respect to the recruitment of U.S. workers. (c) By the 60th day of the recruitment period, or 20 days...

  2. 40 CFR 35.108 - Funding period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Funding period. 35.108 Section 35.108... ASSISTANCE Environmental Program Grants Preparing An Application § 35.108 Funding period. The Regional Administrator and applicant may negotiate the length of the funding period for environmental program grants...

  3. 12 CFR 219.24 - Retention period.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Retention period. 219.24 Section 219.24 Banks...) Recordkeeping and Reporting Requirements for Funds Transfers and Transmittals of Funds § 219.24 Retention period. All records that are required to be retained by this subpart shall be retained for a period of five...

  4. 7 CFR 1.417 - Review period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Review period. 1.417 Section 1.417 Agriculture Office... Conservation and Shortage Relief Act of 1990 (16 U.S.C. 620 et seq.) § 1.417 Review period. (a) Review of... close of the comment period to review the written comments at the Regional Forester's office during...

  5. 7 CFR 1.416 - Comment period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Comment period. 1.416 Section 1.416 Agriculture Office... Conservation and Shortage Relief Act of 1990 (16 U.S.C. 620 et seq.) § 1.416 Comment period. Written comments... and by the Regional Forester by the 30th day of the comment period. ...

  6. 42 CFR 136a.33 - Grace period.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Grace period. 136a.33 Section 136a.33 Public Health... HEALTH AND HUMAN SERVICES INDIAN HEALTH Transition Provisions § 136a.33 Grace period. (a) Upon the... of the new eligibility regulations) shall retain their eligibility for a six month grace period...

  7. 40 CFR 35.9035 - Budget period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Budget period. 35.9035 Section 35.9035... ASSISTANCE Financial Assistance for the National Estuary Program § 35.9035 Budget period. An applicant may choose its budget period in consultation with and subject to the approval of the Regional Administrator. ...

  8. 40 CFR 716.65 - Reporting period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Reporting period. 716.65 Section 716... HEALTH AND SAFETY DATA REPORTING General Provisions § 716.65 Reporting period. Unless otherwise required... mixture , the reporting period for a listed chemical substance or listed mixture will terminate 60 days...

  9. 40 CFR 35.538 - Project period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Project period. 35.538 Section 35.538... ASSISTANCE Environmental Program Grants for Tribes Performance Partnership Grants § 35.538 Project period. If... that is added to a Performance Partnership Grant extends beyond the end of the project period for the...

  10. 77 FR 73452 - Grace Period Study

    Science.gov (United States)

    2012-12-10

    ... Patent and Trademark Office Grace Period Study ACTION: Proposed collection; comment request. SUMMARY: The...Collection@uspto.gov . Include ``0651- 00xx Grace Period Study comment'' in the subject line of the message... United States' grace period, which permits exceptions to absolute novelty, figures centrally in the...

  11. 32 CFR 552.80 - Suspension period.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Suspension period. 552.80 Section 552.80 National... Suspension period. All solicitation privileges suspended by installation commanders will be for a specific time. Normally, it will not exceed 2 years. When the suspension period expires, the agent may...

  12. 5 CFR 9901.512 - Probationary periods.

    Science.gov (United States)

    2010-01-01

    ... from which an employee is separated for performance or conduct does not count toward completion of... service toward completion of the supervisory probationary period. (i) An employee who is reassigned... Probationary periods. (a) Initial probationary period. (1) An employee who is given a career, career...

  13. 49 CFR 236.588 - Periodic test.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Periodic test. 236.588 Section 236.588..., Train Control and Cab Signal Systems Inspection and Tests; Locomotive § 236.588 Periodic test. Except as provided in § 236.586, periodic test of the automatic train stop, train control, or cab signal...

  14. Report made on behalf of the commission of economic affairs, environment and territory about the law project (no. 1613), relative to the electric and gas public utilities and to the power and gas companies; Rapport fait au nom de la Commission des affaires economiques, de l'environnement et du territoire sur le projet de loi (no. 1613), relatif au service public de l'electricite et du gaz et aux entreprises electriques et gazieres

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, J.C.

    2004-06-01

    The aim of this report is to present to the French deputies the comments made by the commission of economic affairs, environment and territory about the law project relative to the change of status of the power and gas public utilities in the framework of the deregulation of European energy markets. This law changes the juridical status of the two state monopolies Electricite de France (EdF) and Gaz de France (GdF) into two anonymous companies and creates two additional companies for the management of the power and gas networks. It ensures also the transposition of the European directives from June 26, 2003 (2003/54/CE and 2003/55/CE). It contains some proper dispositions and modifies various existing French laws, in particular the law no. 46-628 from April 8, 1946 about the electricity and gas nationalization and the law no. 2000-108 from February 10, 2000 relative to the modernization and development of the electric public utility. The first part of the document reports on the general discussions about the law project while the second part makes a detailed analysis of each article with some proposals of modifications. A comparative table puts in parallel the existing texts, the law project and the proposals made by the commission. (J.S.)

  15. Investigation of Methane Hydrate Formation in a Recirculating Flow Loop: Modeling of the Kinetics and Tests of Efficiency of Chemical Additives on Hydrate Inhibition Étude de la formation de l'hydrate de méthane dans une conduite de recirculation : modélisation de la cinétique et tests d'efficacité d'additifs chimiques inhibiteurs d'hydrates de gaz

    Directory of Open Access Journals (Sweden)

    Peytavy J. L.

    2006-12-01

    Full Text Available Gas hydrates can be formed when light gases, such as the components of natural gas, come into contact with water under particular conditions of temperature and pressure. These solid compounds give rise to problems in natural gas and oil industry because they can plug pipelines and process equipment. To prevent hydrate formation methanol and glycols are commonly and extensively used as inhibitors. Today, the thermodynamic equilibria of hydrate formation are well known, but the kinetics of gas hydrate formation and growth has to be studied in order to find means of controlling these processes and to explore the mechanisms for hydrate formation that follows non equilibrium laws. The present work deals with the kinetics of methane hydrate formation studied in a laboratory loop where the liquid blend saturated with methane is circulated up to a pressure of 75 bar. Pressure is maintained at a constant value during experimental runs by means of methane gas make-up. First the effects of pressure (35-75 bar, liquid velocity (0. 5-3 m/s, liquid cooling temperature ramp (2-15°C/h, and liquid hydrocarbon amount (0-96%, on hydrate formation kinetics are investigated. Then a new method is proposed to predict firstly the thermodynamic conditions (pressure and temperature at the maximum values of the growth rate of methane hydrate and secondly the methane hydrate growth rate. A good agreement is found between calculated and experimental data. Finally the evaluation of the efficiency of some kinetic additives and some surfactants developed to avoid either nucleation or crystal growth and agglomeration of methane hydrates is tested based on the proposed experimental procedure. Les hydrates de gaz des composés légers du gaz naturel se forment lorsque ceux-ci entrent en contact avec l'eau dans certaines conditions de température et de pression. Ces composés solides sont nuisibles pour les industries gazière et pétrolière car des bouchons solides peuvent

  16. Advice presented on behalf of the commission of finances, economy and plan about the law project (no. 1613) relative to the electric and gas public utilities and to the power and gas companies; Avis presente au nom de la Commission des finances, de l'economie generale et du plan sur le projet de loi (no. 1613), relatif au service public de l'electricite et du gaz et aux entreprises electriques et gazieres

    Energy Technology Data Exchange (ETDEWEB)

    Carayon, B.

    2004-06-01

    The aim of this report is to present to the French deputies the advice of the commission of finances and economy about the law project relative to the change of status of the power and gas public utilities in the framework of the deregulation of European energy markets. This law changes the juridical status of the two state monopolies Electricite de France (EdF) and Gaz de France (GdF) into two anonymous companies and creates two additional companies for the management of the power and gas networks. It ensures also the transposition of the European directives from June 26, 2003 (2003/54/CE and 2003/55/CE). It contains some proper dispositions and modifies various existing French laws, in particular the law no. 46-628 from April 8, 1946 about the electricity and gas nationalization and the law no. 2000-108 from February 10, 2000 relative to the modernization and development of the electric public utility. The first part of the document reports on the general discussions and comments made by the commission about the law project while the second part concerns the detailed analysis of the articles 16 and 22 about the pension funds of EdF and GdF agents and the change of the status of both utilities. The amendments adopted by the commission for these articles conclude the report. (J.S.)

  17. 38 CFR 3.17 - Disability and death pension; Mexican border period and later war periods.

    Science.gov (United States)

    2010-07-01

    ... pension; Mexican border period and later war periods. 3.17 Section 3.17 Pensions, Bonuses, and Veterans... Compensation General § 3.17 Disability and death pension; Mexican border period and later war periods. In... service which began before and extended into the Mexican border period or ended during World War I,...

  18. Quasi-Periodically Driven Quantum Systems

    Science.gov (United States)

    Verdeny, Albert; Puig, Joaquim; Mintert, Florian

    2016-10-01

    Floquet theory provides rigorous foundations for the theory of periodically driven quantum systems. In the case of non-periodic driving, however, the situation is not so well understood. Here, we provide a critical review of the theoretical framework developed for quasi-periodically driven quantum systems. Although the theoretical footing is still under development, we argue that quasi-periodically driven quantum systems can be treated with generalisations of Floquet theory in suitable parameter regimes. Moreover, we provide a generalisation of the Floquet-Magnus expansion and argue that quasi-periodic driving offers a promising route for quantum simulations.

  19. Correspondence Between Astronomical Periods and Sedimentary Cycles

    Institute of Scientific and Technical Information of China (English)

    Cheng Rihui; You Haitao

    2000-01-01

    It is shown from detailed study that there are some genetic relationships between outer events of celestial bodies and inner geological events of the earth, such as some kinds of correspondences between astronomical periods and sedimentary cycles. The time spans of movement periods of the solar system around the center of the galaxy and cross the plain of the galaxy, the periods of the earth orbit (Milankovitch period) and periods of sunspot are coincided with that of respective sedimentary cycles. It is suggested that the gravity and magnetic changes of the earth leading up to the global climatic and sea level changes are the dynamics of sedimentary cycles.

  20. Dehumidification by dessiccant regenerated by natural gas at the Campeau ice rink in Gatineau; La deshumidification par dessiccant regenere par le gaz naturel a l'Arena Campeau de Gatineau

    Energy Technology Data Exchange (ETDEWEB)

    Lajoie, S.

    2003-03-01

    As air quality gains in importance, dehumidification by dessiccant represents an interesting technological solution, especially in ice rinks where bad air quality (carbon monoxide) is not unknown. Contrary to conventional technologies, dehumidification by dessiccant allows to maintain adequate levels of air quality and optimum humidity levels. Three major advantages are: improved user comfort, the building structure is protected from corrosion, and superior air quality levels are achieved. The document first provided the reader with a brief overview of conventional mechanical dehumidification systems before discussing dehumidification by natural gas dessiccant. A quick historical review of the Campeau ice rink in Gatineau, Quebec was provided, including results obtained. The article concluded by indicating that the technology offers interesting potential for ice rinks. Energy savings are made possible through the utilization of this technology, and improves revenues by stretching operations for longer periods. 1 tab., 1 fig.

  1. Homogenization of some radiative heat transfer models: application to gas-cooled reactor cores; Homogeneisation de modeles de transferts thermiques et radiatifs: application au coeur des reacteurs a caloporteur gaz

    Energy Technology Data Exchange (ETDEWEB)

    El Ganaoui, K

    2006-09-15

    In the context of homogenization theory we treat some heat transfer problems involving unusual (according to the homogenization) boundary conditions. These problems are defined in a solid periodic perforated domain where two scales (macroscopic and microscopic) are to be taken into account and describe heat transfer by conduction in the solid and by radiation on the wall of each hole. Two kinds of radiation are considered: radiation in an infinite medium (non-linear problem) and radiation in cavity with grey-diffuse walls (non-linear and non-local problem). The derived homogenized models are conduction problems with an effective conductivity which depend on the considered radiation. Thus we introduce a framework (homogenization and validation) based on mathematical justification using the two-scale convergence method and numerical validation by simulations using the computer code CAST3M. This study, performed for gas cooled reactors cores, can be extended to other perforated domains involving the considered heat transfer phenomena. (author)

  2. Correlating Bacharach opacity in fuel oil exhaust. Prediction of the operating parameters that reduce it; Correlation de l'opacite Bacharach des gaz d'echappement. Prediction des parametres operateurs qui la reduisent

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, M.; Coello, J.; Maspoch, S.; Puigdomenech, A. [Universitat Autonoma de Barcelona, Dept. de Quimica (Spain); Peralta, X.; Gonzalez, J.M.; Torres, J. [Asfaltos Espanoles SA, Refineria de Tarragona (Spain)

    2000-07-01

    A study was conducted with a view to determining the steps to be taken in order to control the Bacharach opacity of smoke released by different types of engines powered by fuel oil through the same chimney. A statistical model was constructed to relate Bacharach opacity to the operational parameters of the burning equipment on the basis of information recorded during its routine functioning over a period of about one year, with no laboratory experiments nor intentional alteration of such parameters. Different chemo-metric tools were applied to the data recorded over a period long enough to ensure a good model. Owing to the high complexity of the data handled (equipment parameters, fuel oil properties, operating conditions, etc.), the model was constructed by using different tools that were tested in order of increasing complexity. Thus, a Principal Component Analysis (PCA) was initially conducted on the variables defining the different types of fuel oil used in order to suppress their high correlation. The scores obtained from this analysis were used as the fuel data in the subsequent steps. Owing to the high complexity of the parameters involved, linear regression methods were not functional, so the non-linear regression method Alternating Conditional Expectations (ACE) had to be used instead to determine the influence of these parameters on Bacharach opacity. After the model was constructed, the parameters that govern opacity were determined and the model was experimentally validated by exploring the variables that can be modified at plant level (viz. the combination of conradson coke and asphaltenes in the fuel, the oil viscosity at burner and the proportion of oxygen in the furnace). Changes in these variables were found to alter the properties of the stack; also, the predictions of the ACE model were confirmed. Consequently, the proposed methodology allows the effective control of smoke released by the equipment. (authors)

  3. A highly specific test for periodicity

    Energy Technology Data Exchange (ETDEWEB)

    Ansmann, Gerrit, E-mail: gansmann@uni-bonn.de [Department of Epileptology, University of Bonn, Sigmund-Freud-Straße 25, 53105 Bonn (Germany); Helmholtz Institute for Radiation and Nuclear Physics, University of Bonn, Nussallee 14–16, 53115 Bonn (Germany); Interdisciplinary Center for Complex Systems, University of Bonn, Brühler Straße 7, 53175 Bonn (Germany)

    2015-11-15

    We present a method that allows to distinguish between nearly periodic and strictly periodic time series. To this purpose, we employ a conservative criterion for periodicity, namely, that the time series can be interpolated by a periodic function whose local extrema are also present in the time series. Our method is intended for the analysis of time series generated by deterministic time-continuous dynamical systems, where it can help telling periodic dynamics from chaotic or transient ones. We empirically investigate our method's performance and compare it to an approach based on marker events (or Poincaré sections). We demonstrate that our method is capable of detecting small deviations from periodicity and outperforms the marker-event-based approach in typical situations. Our method requires no adjustment of parameters to the individual time series, yields the period length with a precision that exceeds the sampling rate, and its runtime grows asymptotically linear with the length of the time series.

  4. Uniformly Almost Periodic Functions and Almost Periodic Solutions to Dynamic Equations on Time Scales

    Directory of Open Access Journals (Sweden)

    Yongkun Li

    2011-01-01

    Full Text Available Firstly, we propose a concept of uniformly almost periodic functions on almost periodic time scales and investigate some basic properties of them. When time scale T=ℝ or ℤ, our definition of the uniformly almost periodic functions is equivalent to the classical definitions of uniformly almost periodic functions and the uniformly almost periodic sequences, respectively. Then, based on these, we study the existence and uniqueness of almost periodic solutions and derive some fundamental conditions of admitting an exponential dichotomy to linear dynamic equations. Finally, as an application of our results, we study the existence of almost periodic solutions for an almost periodic nonlinear dynamic equations on time scales.

  5. Quebec inventory of greenhouse gas emissions in 2008 and their evolution since 1990; Inventaire quebecois des emissions de gaz a effet de serre en 2008 et leur evolution depuis 1990

    Energy Technology Data Exchange (ETDEWEB)

    Leblond, V.; Paradis, J.; Bougie, R.; Goulet, M.; Leclerc, N.; Nolet, E.

    2010-11-15

    This document presented an inventory of greenhouse gas (GHG) emissions produced by human activity in Quebec between 1990 and 2008. In 2008, 82.7 Mt of carbon dioxide (CO{sub 2}) equivalent were released in Quebec, which represents a 1.2 percent reduction from 1990 levels. Quebec had the second lowest GHG emissions per capita in 2008 and was 1 of only 3 only provinces in Canada to have a reduction in GHG emissions since 1990. This document also presented data regarding GHG emissions released by sector, notably from industrial combustion such as the TransCanada Energy cogeneration facilities; industrial processes; residential, commercial and institutional buildings; agriculture; sanitary landfills; and electric power production. Quebec's reduction in GHG emissions can be attributed primarily to advances in energy efficiency technology that have been adopted by the industrial sector. In addition, some industrial combustion facilities have been closed and landfill facilities have begun to use systems to capture methane gas. In contrast, automobile traffic increased over the study period, and was responsible for an important increase in GHG emissions since 1990. 6 tabs., 4 figs.

  6. Advances in gas flow metering - end of the history, peaceful co-existence or a new beginning; Les avancees dans le mesurage des debits de gaz - fin de l'histoire, coexistence pacifique ou nouveau commencement

    Energy Technology Data Exchange (ETDEWEB)

    Studzinski, W. [NOVA Research and Technology Centre, Calgary (Canada)

    2000-07-01

    Gas flow metering plays an important role in the technical and fiscal operations of pipeline systems. Over the last hundred years, the industry has gone through several technical revolutions. The recent two decades were characterized by the introduction of flow computers in the 80's and acceptance of ultrasonic meters in the 90's. These changes, associated with measurement technology, have had a profound impact on pipeline operation, deregulation of the gas industry and gas trading. Significant advances were made, however, it is certainly not the end for progress in gas flow metering. The future development of optoelectronic and mass flow meters combined with advances in telemetry and tele-calibration may significantly reduce capital and maintenance costs. Classical flow meters will be upgraded to a new level of performance and will co-exist with the newest technologies. The uncertainty of flow measurement will be improved, mainly in terms of stability over longer periods of time. Old and new meters will be able to perform in environments other than dry natural gas. Processing of flow measurement data will evolve with the progress in flow computers and smart transmitters. The advances in gas flow metering will be driven by life cycle cost reduction as well as new business and service requirements. (author)

  7. Gabor systems on discrete periodic sets

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Due to its good potential for digital signal processing, discrete Gabor analysis has interested some mathematicians. This paper addresses Gabor systems on discrete periodic sets, which can model signals to appear periodically but intermittently. Complete Gabor systems and Gabor frames on discrete periodic sets are characterized; a sufficient and necessary condition on what periodic sets admit complete Gabor systems is obtained; this condition is also proved to be sufficient and necessary for the existence of sets E such that the Gabor systems generated by χE are tight frames on these periodic sets; our proof is constructive, and all tight frames of the above form with a special frame bound can be obtained by our method; periodic sets admitting Gabor Riesz bases are characterized; some examples are also provided to illustrate the general theory.

  8. Periods of weed interference in cowpea

    Directory of Open Access Journals (Sweden)

    Maria José Pinheiro Corrêa

    2015-12-01

    Full Text Available This work aimed to determine the periods weed interference in cowpea. The experimental design was randomized blocks, and the treatments consisted of periods of control or coexistence with the culture. The periods of control or weed coexistence after culture emergence were: 0-10, 0-20, 0-30, 0-40, 0-50, 0-60 and 0 – 80 days after crop emergence. The main weed density were: AlternantheratenellaColla,CyperusrotundusL., Digitariaciliaris(Retz. Koeler, Eleusineindica(L.Gaertn,MollugoverticillataL.Considering 5% of tolerance in cowpea yield reduction, the period prior interference was 8 days after emergence (DAE, total period of interference prevention was 53 DAE and critical period of interference prevention between 8 and 53 DAE. Weed interference reduced the grainyield up to 46%.

  9. Gabor systems on discrete periodic sets

    Institute of Scientific and Technical Information of China (English)

    LI YunZhang; LIAN QiaoFang

    2009-01-01

    Due to its good potential for digital signal processing,discrete Gabor analysis has inter ested some mathematicians.This paper addresses Gabor systems on discrete periodic sets,which can model signals to appear periodically but intermittently.Complete Gabor systems and Gabor frames on discrete periodic sets are characterized; a sufficient and necessary condition on what periodic sets admit complete Gabor systems is obtained; this condition is also proved to be sufficient and necessary for the existence of sets E such that the Gabor systems generated by XE are tight frames on these periodic sets; our proof is constructive,and all tight frames of the above form with a special frame bound can be obtained by our method; periodic sets admitting Gabor Riesz bases are characterized;some examples are also provided to illustrate the general theory.

  10. Preparing to perform: periodization and dance.

    Science.gov (United States)

    Wyon, Matthew

    2010-01-01

    This article reviews the historical and current literature on periodization in sport before applying the concept to dance from scientific and anecdotal points of view. Preparing the dancer through the use of a periodization model, in a professional or vocational setting, will potentially help prevent overtraining and its link to injury, while improving the dancer's readiness to perform optimally. Practical examples of tapering and periodization of training are discussed for companies and vocational schools.

  11. Measuring stellar rotation periods with Kepler

    CERN Document Server

    Nielsen, M B; Schunker, H; Karoff, C

    2015-01-01

    We measure rotation periods for 12151 stars in the Kepler field, based on the photometric variability caused by stellar activity. Our analysis returns stable rotation periods over at least six out of eight quarters of Kepler data. This large sample of stars enables us to study the rotation periods as a function of spectral type. We find good agreement with previous studies and vsini measurements for F, G and K stars. Combining rotation periods, B-V color, and gyrochronology relations, we find that the cool stars in our sample are predominantly younger than ~1Gyr.

  12. Cyclical period changes in Z Chamaeleontis

    CERN Document Server

    Baptista, R; Oliveira, E; Vrielmann, S; Woudt, P A; Catalan, M S

    2002-01-01

    We report the identification of cyclical changes in the orbital period of the eclipsing dwarf nova Z Cha. We used times of mid-eclipse collected from the literature and our new eclipse timings to construct an observed-minus-calculated diagram covering 30 years of observations (1972-2002). The data present cyclical variations that can be fitted by a linear plus sinusoidal function with period 28+/-2 yr and amplitude 1.0+/-0.2 minute. The statistical significance of this period by an F-test is larger than 99.9%. The derived fractional period change, Delta P/P= 4.4 x 10^{-7}, is comparable to that of other short-period cataclysmic variables (CVs), but is one order of magnitude smaller than those of the long-period CVs. Separate fits to the first and second half of the data lead to ephemerides with quite different cycle periods and amplitudes, indicating that the variation is not sinusoidal or, most probably, is not strictly periodic. The observed cyclical period change is possibly caused by a solar-type magnetic...

  13. Exact analysis of bi-periodic structures

    CERN Document Server

    Cai, C W; Chan, H C

    2002-01-01

    By using the U-transformation method, it is possible to uncouple linear simultaneous equations, either algebraic or differential, with cyclic periodicity. This book presents a procedure for applying the U-transformation technique twice to uncouple the two sets of unknown variables in a doubly periodic structure to achieve an analytical exact solution. Explicit exact solutions for the static and dynamic analyses for certain engineering structures with doubly periodic properties - such as a continuous truss with any number of spans, cable network and grillwork on supports with periodicity, and g

  14. Periodic Motion near the Surface of Asteroids

    CERN Document Server

    Jiang, Yu; Li, Hengnian

    2015-01-01

    We are interested in the periodic motion and bifurcations near the surface of an asteroid. The gravity field of an irregular asteroid and the equation of motion of a particle near the surface of an asteroid are studied. The periodic motions around the major body of triple asteroid 216 Kleopatra and the OSIRIS REx mission target asteroid 101955 Bennu are discussed. We find that motion near the surface of an irregular asteroid is quite different from the motion near the surface of a homoplastically spheroidal celestial body. The periodic motions around the asteroid 101955 Bennu and 216 Kleopatra indicate that the geometrical shapes of the orbits are probably very sophisticated. There exist both stable periodic motions and unstable periodic motions near the surface of the same irregular asteroid. This periodic motion which is unstable can be resonant or non resonant. The period doubling bifurcation and pseudo period doubling bifurcation of periodic orbits coexist in the same gravity field of the primary of the t...

  15. Gas distribution management; elaboration of Gas Supply Triennial Plan. Circular of 21 April 1999; Organisation de la distribution du gaz; elaboration du Plan triennal de desserte gaziere. Circulaire du 21 avril 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-07

    The circular of 21 April 1999 issued by the Secretary of State for Industry of the French government concerns the gas distribution and the manner of elaboration of the Plan of gas supply. The recipients are asked, by observing the legislative and regulatory provisions, to contribute by working out the departmental components of the national gas distribution plan. They should establish the list of localities where works for gas distribution should start within three years from the data of plan launching. The circular mentions: I. the context and the concept of the Gas Supply Plan; II. the transitory period; III. criteria of setting in the plan; IV. request for setting, treatment of the request and publication of the plan. The juridical context is established as well as the application field of the circular. Concerning the criteria of setting in the plan one appeals to minimal requirements of economic efficiency and profitableness. Steps from submitting the demand through transmission of the departmental plan proposal to minister in charge with energy are explained. Appendix I establishes the criteria of payback and the evaluation method, Appendix II and Appendix III give models for calculation form and tables for incomes and expenses, respectively. The circular contains also attached two documents, one titled 'The large gas infrastructures' and the other 'Structure of gas sector in France'. The development of European grid, as prelude to a more open market and the development strategies for European operators are presented, as well as the present situation and evolution of the gas sector in France.

  16. 38 CFR 3.252 - Annual income; pension; Mexican border period and later war periods.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Annual income; pension; Mexican border period and later war periods. 3.252 Section 3.252 Pensions, Bonuses, and Veterans' Relief... Dependency, Income and Estate § 3.252 Annual income; pension; Mexican border period and later war periods....

  17. Uniformly Asymptotic Stability and Existence of Periodic Solutions and Almost Periodic Solutions

    Institute of Scientific and Technical Information of China (English)

    林发兴

    1994-01-01

    We introduce the concepts of uniformly stable solutions and uniformly-asymptotically stable solutions, and then give the relation between Lyapunov function and those concepts. Furthermore, we establish the theorem that an almost periodic system or periodic system has uniformly-asymptotically stable solutions and Lipschitz’ condition has an almost periodic solution or periodic solution.

  18. On almost periodic solutions of logistic delay differential equations with almost periodic time dependence

    Science.gov (United States)

    Yuan, Rong

    2007-06-01

    In this paper, we study almost periodic logistic delay differential equations. The existence and module of almost periodic solutions are investigated. In particular, we extend some results of Seifert in [G. Seifert, Almost periodic solutions of certain differential equations with piecewise constant delays and almost periodic time dependence, J. Differential Equations 164 (2000) 451-458].

  19. Dry period length of dairy cows :

    NARCIS (Netherlands)

    Vries, de Ruben

    2017-01-01

    A dry period of dairy cows is historically seen as a period during which the cow can restore its body condition and regenerate its mammary epithelium in order to be high yielding in the successive lactation. Recent work has indicated that high yielding cows generally experience a severe negative ene

  20. Project 2nd Periodic Report - Section 2

    DEFF Research Database (Denmark)

    Healy, Mark; Knowles, Emma; Johnstone, Cameron

    The work described in this publication has received support from the European Community - Research Infrastructure Action under the FP7 “Capacities” Specific Programme through grant agreement number 262552, MaRINET. Project Periodic Report. 2nd Period: October 2012 – March 2014 inclusive....

  1. Short Periodicities in Latitudinal Variation of Sunspots

    Science.gov (United States)

    Kim, Bang-Yeop; Chang, Heon-Young

    2011-06-01

    The latitudinal variation of sunspots appearing during the period from 1874 to 2009 has been studied in terms of centerof- latitude (COL). The butterfly diagram has been used to study the evolution of the magnetic field and the dynamics at the bottom of the solar convection zone. Short-term periodicities have been of particular interest, in that they are somehow related to the structure and dynamics of the solar interior. We thus have focused our investigation on shortterm periodicities. We first calculated COL by averaging the latitude of sunspots with the weight function in area. Then, we analyzed the time series of COL using the wavelet transform technique. We found that a periodicity of ~5 years is the most dominant feature in the time series of COL, with the exception of the ~11 year solar cycle itself. This periodicity can be easily understood by considering small humps between the minima in the area-weighted butterfly diagram. However, we find that periodicities of ~1.3 (0.064), ~1.5 (0.056), or ~1.8 (0.046) years ( 1/ month ), which have been previously suggested as evidence of links between the changing structure of the sunspot zone and the tachocline rotation rate oscillations, are insignificant and inconsistent. We therefore conclude that the only existing short-term periodicity is of ~5 years, and that periodicities of ~1.3, ~1.5, or ~1.8 years are likely to be artifacts due to random noise of small sunspots.

  2. BIVARIATE REAL-VALUED ORTHOGONAL PERIODIC WAVELETS

    Institute of Scientific and Technical Information of China (English)

    Qiang Li; Xuezhang Liang

    2005-01-01

    In this paper, we construct a kind of bivariate real-valued orthogonal periodic wavelets. The corresponding decomposition and reconstruction algorithms involve only 8 terms respectively which are very simple in practical computation. Moreover, the relation between periodic wavelets and Fourier series is also discussed.

  3. 7 CFR 956.13 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 956.13 Section 956.13 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... VALLEY OF SOUTHEAST WASHINGTON AND NORTHEAST OREGON Definitions § 956.13 Fiscal period. Fiscal...

  4. 7 CFR 958.112 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 958.112 Section 958.112 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... COUNTIES IN IDAHO, AND MALHEUR COUNTY, OREGON Rules and Regulations § 958.112 Fiscal period. The...

  5. 7 CFR 1212.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1212.7 Section 1212.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS..., Consumer Education, and Industry Information Order Definitions § 1212.7 Fiscal period. “Fiscal...

  6. 7 CFR 925.112 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 925.112 Section 925.112 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... SOUTHEASTERN CALIFORNIA Rules and Regulations § 925.112 Fiscal period. Beginning January 1, 1988, fiscal...

  7. 7 CFR 906.15 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Fiscal period. 906.15 Section 906.15 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIO GRANDE VALLEY IN TEXAS Order Regulating Handling Definitions § 906.15 Fiscal period. Fiscal...

  8. 7 CFR 1206.7 - Fiscal period.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Fiscal period. 1206.7 Section 1206.7 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS... INFORMATION Mango Promotion, Research, and Information Order Definitions § 1206.7 Fiscal period. Fiscal...

  9. David's Understanding of Functions and Periodicity

    Science.gov (United States)

    Gerson, Hope

    2008-01-01

    This is a study of David, a senior enrolled in a high school precalculus course. David's understandings of functions and periodicity was explored, through clinical interviews and contextualized through classroom observations. Although David's precalculus class was traditional his understanding of periodic functions was unconventional David engaged…

  10. Online Periodic Table: A Cautionary Note

    Science.gov (United States)

    Izci, Kemal; Barrow, Lloyd H.; Thornhill, Erica

    2013-01-01

    The purpose of this study was (a) to evaluate ten online periodic table sources for their accuracy and (b) to compare the types of information and links provided to users. Limited studies have been reported on online periodic table (Diener and Moore 2011; Slocum and Moore in "J Chem Educ" 86(10):1167, 2009). Chemistry students'…

  11. 18 CFR 367.5 - Accounting period.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Accounting period. 367.5 Section 367.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Instructions § 367.5 Accounting period. Each service company must keep its books on a monthly basis so that...

  12. 46 CFR 403.115 - Accounting period.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Accounting period. 403.115 Section 403.115 Shipping COAST GUARD (GREAT LAKES PILOTAGE), DEPARTMENT OF HOMELAND SECURITY GREAT LAKES PILOTAGE UNIFORM ACCOUNTING SYSTEM General § 403.115 Accounting period. Each Association subject to this part shall...

  13. 24 CFR 886.332 - Rehabilitation period.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Rehabilitation period. 886.332... Assistance Program for the Disposition of HUD-Owned Projects § 886.332 Rehabilitation period. (a) Immediate start of rehabilitation after sales closing. After the execution of the Agreement and the sales...

  14. Nonlinear quasimodes near elliptic periodic geodesics

    CERN Document Server

    Albin, Pierre; Marzuola, Jeremy L; Thomann, Laurent

    2011-01-01

    We consider the nonlinear Schr\\"odinger equation on a compact manifold near an elliptic periodic geodesic. Using a geometric optics construction, we construct quasimodes to a nonlinear stationary problem which are highly localized near the periodic geodesic. We show the nonlinear Schr\\"odinger evolution of such a quasimode remains localized near the geodesic, at least for short times.

  15. 47 CFR 24.15 - License period.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false License period. 24.15 Section 24.15 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PERSONAL COMMUNICATIONS SERVICES Applications and Licenses General Filing Requirements § 24.15 License period. Licenses for...

  16. Automatically identifying periodic social events from Twitter

    NARCIS (Netherlands)

    Kunneman, F.A.; Bosch, A.P.J. van den

    2015-01-01

    Many events referred to on Twitter are of a periodic nature, characterized by roughly constant time intervals in between occurrences. Examples are annual music festivals, weekly television programs, and the full moon cycle. We propose a system that can automatically identify periodic events from Twi

  17. Multi-periodic nanostructures for photon control

    DEFF Research Database (Denmark)

    Kluge, Christian; Adam, Jost; Barié, Nicole;

    2014-01-01

    We propose multi-periodic nanostructures yielded by superposition of multiple binary gratings for wide control over photon emission in thin-film devices. We present wavelength- and angle-resolved photoluminescence measurements of multi-periodically nanostructured organic light-emitting layers...

  18. Studying the Nazi Period: Some Considerations.

    Science.gov (United States)

    Molnar, Alex; And Others

    1984-01-01

    Students should be taught how to make well-reasoned and analytic judgments about the Nazis. The process of arriving at judgments about the Nazi period should be characterized by a factual knowledge of the Nazi era within a general historical knowledge of the period, sympathy, and an open mind. (RM)

  19. 28 CFR 524.75 - Periodic review.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Periodic review. 524.75 Section 524.75... TRANSFER CLASSIFICATION OF INMATES Central Inmate Monitoring (CIM) System § 524.75 Periodic review. The Warden shall ensure that the status of an inmate's CIM assignment is considered at each program...

  20. 12 CFR 226.7 - Periodic statement.

    Science.gov (United States)

    2010-01-01

    ... telephone numbers and the Web site operated by or on behalf of the Federal Reserve Board. A small depository... period and calendar year to date, using a format substantially similar to Sample G-18(A) in appendix G to... period and calendar year to date, using a format substantially similar to Sample G-18(A) in appendix...

  1. Hiss emissions during quiet and disturbed periods

    Indian Academy of Sciences (India)

    D K Singh; R P Singh

    2002-10-01

    The characteristic features of VLF hiss emissions during quiet and disturbed conditions observed at ground stations and on-board satellites are summarized. The increased intensity of the hiss emissions during magnetic storm period is explained by considering the enhanced flux of energetic electrons during magnetic storm period. The generation and propagation mechanism of VLF hiss are also briefly discussed.

  2. Local field effects in periodic metamaterials

    Science.gov (United States)

    Porvatkina, O. V.; Tishchenko, A. A.; Strikhanov, M. N.

    2016-08-01

    In this article we investigate dielectric and magnetic properties of periodic metamaterials taking into account the so-called local field effect, caused by interaction between single particles the material consists of. We also consider the spatial dispersion effects. As a result, generalized Clausius-Mossotti techniques have been extended to the case of periodic metamaterials; permittivity tensor and permeability tensor were obtained.

  3. Periodical Literature of Tropical and Subtropical Agriculture

    Science.gov (United States)

    Lawani, S. M.

    1972-01-01

    In order to foster improvements in bibliographical control, this study attempts to provide some information on the periodicals in which articles on tropical and subtropical agriculture are published. The periodicals in which publications most frequently appear are listed, and the extent of bibliographic scattering and language of publication are…

  4. Online Periodic Table: A Cautionary Note

    Science.gov (United States)

    Izci, Kemal; Barrow, Lloyd H.; Thornhill, Erica

    2013-01-01

    The purpose of this study was (a) to evaluate ten online periodic table sources for their accuracy and (b) to compare the types of information and links provided to users. Limited studies have been reported on online periodic table (Diener and Moore 2011; Slocum and Moore in "J Chem Educ" 86(10):1167, 2009). Chemistry students'…

  5. Asymptotically periodic solutions of Volterra integral equations

    Directory of Open Access Journals (Sweden)

    Muhammad N. Islam

    2016-03-01

    Full Text Available We study the existence of asymptotically periodic solutions of a nonlinear Volterra integral equation. In the process, we obtain the existence of periodic solutions of an associated nonlinear integral equation with infinite delay. Schauder's fixed point theorem is used in the analysis.

  6. 24 CFR 221.775 - Option period.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Option period. 221.775 Section 221.775 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... § 221.775 Option period. The mortgagee may exercise its option to assign within one year following the...

  7. 14 CFR 23.49 - Stalling period.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Stalling period. 23.49 Section 23.49 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... period. (a) VSOand VS1are the stalling speeds or the minimum steady flight speeds, in knots (CAS), at...

  8. 40 CFR 503.2 - Compliance period.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Compliance period. 503.2 Section 503.2 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SEWAGE SLUDGE STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.2 Compliance period. (a) Compliance with the standards...

  9. Dry period length of dairy cows

    NARCIS (Netherlands)

    Vries, de Ruben

    2017-01-01

    A dry period of dairy cows is historically seen as a period during which the cow can restore its body condition and regenerate its mammary epithelium in order to be high yielding in the successive lactation. Recent work has indicated that high yielding cows generally experience a severe negative

  10. 29 CFR 1902.33 - Developmental period.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Developmental period. 1902.33 Section 1902.33 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... Section 18(e) of the Act Completion of Developmental Steps-Certification § 1902.33 Developmental period...

  11. Modeling of laser induced periodic surface structures

    NARCIS (Netherlands)

    Skolski, J.Z.P.; Römer, G.R.B.E.; Huis in 't Veld, A.J.; Mitko, V.S.; Obona, J.V.; Ocelik, V.; Hosson, J.T.M. de

    2010-01-01

    In surfaces irradiated by short laser pulses, Laser Induced Periodic Surface Structures (LIPSS) have been observed on all kind of materials for over forty years. These LIPSS, also referred to as ripples, consist of wavy surfaces with periodicity equal or smaller than the wavelength of the laser radi

  12. Automatically identifying periodic social events from Twitter

    NARCIS (Netherlands)

    Kunneman, F.A.; Bosch, A.P.J. van den

    2015-01-01

    Many events referred to on Twitter are of a periodic nature, characterized by roughly constant time intervals in between occurrences. Examples are annual music festivals, weekly television programs, and the full moon cycle. We propose a system that can automatically identify periodic events from

  13. Selecting Full-Text Undergraduate Periodicals Databases.

    Science.gov (United States)

    Still, Julie M.; Kassabian, Vibiana

    1999-01-01

    Examines how libraries and librarians can compare full-text general periodical indices, using ProQuest Direct, Periodical Abstracts (via Ovid), and EBSCOhost as examples. Explores breadth and depth of coverage; manipulation of results (email/download/print); ease of use (searching); and indexing quirks. (AEF)

  14. David's Understanding of Functions and Periodicity

    Science.gov (United States)

    Gerson, Hope

    2008-01-01

    This is a study of David, a senior enrolled in a high school precalculus course. David's understandings of functions and periodicity was explored, through clinical interviews and contextualized through classroom observations. Although David's precalculus class was traditional his understanding of periodic functions was unconventional David engaged…

  15. 17 CFR 285.2 - Periodic reports.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Periodic reports. 285.2 Section 285.2 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) RULES AND REGULATIONS PURSUANT TO SECTION 15(a) OF THE BRETTON WOODS AGREEMENTS ACT § 285.2 Periodic reports. (a)...

  16. Bounded Correctors in Almost Periodic Homogenization

    Science.gov (United States)

    Armstrong, Scott; Gloria, Antoine; Kuusi, Tuomo

    2016-10-01

    We show that certain linear elliptic equations (and systems) in divergence form with almost periodic coefficients have bounded, almost periodic correctors. This is proved under a new condition we introduce which quantifies the almost periodic assumption and includes (but is not restricted to) the class of smooth, quasiperiodic coefficient fields which satisfy a Diophantine-type condition previously considered by Kozlov (Mat Sb (N.S), 107(149):199-217, 1978). The proof is based on a quantitative ergodic theorem for almost periodic functions combined with the new regularity theory recently introduced by Armstrong and Shen (Pure Appl Math, 2016) for equations with almost periodic coefficients. This yields control on spatial averages of the gradient of the corrector, which is converted into estimates on the size of the corrector itself via a multiscale Poincaré-type inequality.

  17. New Realization of Periodic Cycled Separation

    DEFF Research Database (Denmark)

    Toftegard, Bjarne; Clausen, Charlotte H.; Jørgensen, Sten B.;

    2016-01-01

    A new realization of periodic cycled gas/liquid separation is presented. Separation factors and column efficiencies are compared for a column stripping ammonia from water with air, using three different sets of internals: conventional sieve trays, Sulzer BX gauze packings, and periodically cycled...... trays. The proposed new periodic trays are shown to be advantageous compared to their continuous alternatives. It is demonstrated experimentally that periodic tray efficiencies of up to 300% are achievable. With the proposed new tray design, a new operation form is also introduced in which the trays...... are drained sequentially rather than simultaneously, such that the vapor flow is not interrupted during the liquid drainage. For different ratios of counter-current vapor/liquid flow rates, column efficiencies for periodically cycled columns are shown experimentally to be two times greater than those...

  18. Sensitivity analysis of periodic matrix population models.

    Science.gov (United States)

    Caswell, Hal; Shyu, Esther

    2012-12-01

    Periodic matrix models are frequently used to describe cyclic temporal variation (seasonal or interannual) and to account for the operation of multiple processes (e.g., demography and dispersal) within a single projection interval. In either case, the models take the form of periodic matrix products. The perturbation analysis of periodic models must trace the effects of parameter changes, at each phase of the cycle, on output variables that are calculated over the entire cycle. Here, we apply matrix calculus to obtain the sensitivity and elasticity of scalar-, vector-, or matrix-valued output variables. We apply the method to linear models for periodic environments (including seasonal harvest models), to vec-permutation models in which individuals are classified by multiple criteria, and to nonlinear models including both immediate and delayed density dependence. The results can be used to evaluate management strategies and to study selection gradients in periodic environments.

  19. On the Rotation Period of (90377) Sedna

    CERN Document Server

    Gaudi, B S; Hartman, J D; Holman, M J; McLeod, B A; Stanek, Krzysztof Z.; Hartman, Joel D.; Holman, Matthew J.; Leod, Brian A. Mc

    2005-01-01

    We present precise, ~1%, r-band relative photometry of the unusual solar system object (90377) Sedna. Our data consist of 143 data points taken over eight separate nights in October 2004 and January 2005. The RMS variability over the longest contiguous stretch of five nights of data spanning nine days is only ~1.3%. This subset of data alone constrain the amplitude of any long-period variations with period P to be A10 days, unless the intrinsic light curve has significant and comparable power on multiple timescales, which we argue is difficult. A sinusoidal fit yields a number of viable solutions, with a best-fit period of P=(10.273+/-0.003) hours and semi-amplitude of A=(1.0 +/- 0.1)%. Our results indicate that the period of Sedna is likely consistent with typical rotation periods of solar system objects, thus obviating the need for a massive companion to slow its rotation.

  20. On Orbital Period Changes in Nova Outbursts

    CERN Document Server

    Martin, Rebecca G; Schaefer, Bradley E

    2011-01-01

    We propose a new mechanism that produces an orbital period change during a nova outburst. When the ejected material carries away the specific angular momentum of the white dwarf, the orbital period increases. A magnetic field on the surface of the secondary star forces a fraction of the ejected material to corotate with the star, and hence the binary system. The ejected material thus takes angular momentum from the binary orbit and the orbital period decreases. We show that for sufficiently strong magnetic fields on the surface of the secondary star, the total change to the orbital period could even be negative during a nova outburst, contrary to previous expectations. Accurate determinations of pre- and post-outburst orbital periods of recurrent nova systems could test the new mechanism, in addition to providing meaningful constraints on otherwise difficult to measure physical quantities. We apply our mechanism to outbursts of the recurrent nova U Sco.

  1. Hypokalemic periodic paralysis: Three rare secondary causes

    Directory of Open Access Journals (Sweden)

    Prasanna Eswaradass Venkatesan

    2015-01-01

    Full Text Available Periodic paralysis is a rare neuromuscular disorder, related to a defect in muscle ion channels, characterized by episodes of painless muscle weakness, which may be precipitated by heavy exercise, fasting, or high-carbohydrate meals. Hypokalemic periodic paralysis may be familial (primary or secondary. Here, we report three cases of secondary causes of hypokalemic periodic paralysis. On evaluation, case 1 had distal renal tubular acidosis (RTA due to Sjogren′s syndrome, case 2 had drug induced proximal RTA (Fanconi′s syndrome and case 3 had thyrotoxicosis. Clinician must be aware of causes of secondary PP as recognition and diagnosis can completely prevent further attacks of periodic paralysis. Each of the above case is rare, but completely treatable if diagnosed. Low dose steroids with bicarbonate replacement in case 1, stopping tenofovir in case 2 and carbimazole therapy in case 3 prevented further attacks of periodic paralysis and cardiopulmonary complications.

  2. Lise Öğrencilerinin Radon Gazına Yönelik Farkındalıklarının Bazı Değişkenler Açısından İncelenmesi: Nevşehir İli Örneği

    Directory of Open Access Journals (Sweden)

    Mahmut POLAT

    2016-02-01

    Full Text Available Bu çalışmanın temel amacı Radon gazı ve onun çevresel etkilerine ilişkin lise öğrencilerinin farkındalık düzeyinin belirlenmesidir. Çalışmanın bir diğer amacı ise katılımcıların lise öğrenim süresince almış oldukları ilişkili derslere ait kazanımları belirleyerek bunların farkındalık seviyeleriyle olan ilişkilerini ortaya koymaktır. Çalışmada nicel araştırma yöntemlerinden tarama (surway yöntemi kullanılmıştır. Öğrencilerin ortaöğretimin başında ve sonundaki sınıf seviyelerinden seçilmiş olması, öğrenim süreci içindeki değişimi belirleyebilmek açısından kesit araştırma olarak ta kabul edilebilir. Çalışmada ayrıca fen bilimleri derslerinin ilgili sınıf seviyelerine ait öğretim programları incelendiği için doküman taraması da yapılmıştır. Çalışmanın örneklemi; Nevşehir şehir merkezinde bulunan üç farklı okul türünden rastgele olarak seçilen 554 (278 erkek ve 276 kız dokuzuncu ve on ikinci sınıf öğrencisinden oluşmaktadır. Veri toplama aracı olarak araştırmacılar tarafından oluşturulan Radon Farkındalık Anketi (RFA kullanılmıştır. Bu anket üç bölümden ve toplam on maddeden oluşmuştur. Kullanılan veri toplama aracı RFA süreksiz (kesikli türde veriler sağladığından bu verilerin analizinde ki-kare testi, frekans ve yüzde değerleri kullanılmıştır. Örneklemin büyük bir bölümünün Radon farkındalık düzeyi oldukça düşük çıkmıştır. Çalışmaya katılan lise öğrencilerinin büyük çoğunluğu (% 55 Radonu hiç duymadıklarını belirtmişlerdir. Radonu bildiğini ifade edenlerin okul türü ve sınıf seviyelerine göre aralarında anlamlı bir fark bulunmuştur. Bu fark, okul türüne göre fen lisesi ve sınıf seviyesi açısından da 12. sınıf lehine ortaya çıkmıştır.

  3. Wave propagation in axially moving periodic strings

    Science.gov (United States)

    Sorokin, Vladislav S.; Thomsen, Jon Juel

    2017-04-01

    The paper deals with analytically studying transverse waves propagation in an axially moving string with periodically modulated cross section. The structure effectively models various relevant technological systems, e.g. belts, thread lines, band saws, etc., and, in particular, roller chain drives for diesel engines by capturing both their spatial periodicity and axial motion. The Method of Varying Amplitudes is employed in the analysis. It is shown that the compound wave traveling in the axially moving periodic string comprises many components with different frequencies and wavenumbers. This is in contrast to non-moving periodic structures, for which all components of the corresponding compound wave feature the same frequency. Due to this "multi-frequency" character of the wave motion, the conventional notion of frequency band-gaps appears to be not applicable for the moving periodic strings. Thus, for such structures, by frequency band-gaps it is proposed to understand frequency ranges in which the primary component of the compound wave attenuates. Such frequency band-gaps can be present for a moving periodic string, but only if its axial velocity is lower than the transverse wave speed, and, the higher the axial velocity, the narrower the frequency band-gaps. The revealed effects could be of potential importance for applications, e.g. they indicate that due to spatial inhomogeneity, oscillations of axially moving periodic chains always involve a multitude of frequencies.

  4. Reliability, return periods, and risk under nonstationarity

    Science.gov (United States)

    Read, Laura K.; Vogel, Richard M.

    2015-08-01

    Water resources design has widely used the average return period as a concept to inform management and communication of the risk of experiencing an exceedance event within a planning horizon. Even though nonstationarity is often apparent, in practice hydrologic design often mistakenly assumes that the probability of exceedance, p, is constant from year to year which leads to an average return period To equal to 1/p; this expression is far more complex under nonstationarity. Even for stationary processes, the common application of an average return period is problematic: it does not account for planning horizon, is an average value that may not be representative of the time to the next flood, and is generally not applied in other areas of water planning. We combine existing theoretical and empirical results from the literature to provide the first general, comprehensive description of the probabilistic behavior of the return period and reliability under nonstationarity. We show that under nonstationarity, the underlying distribution of the return period exhibits a more complex shape than the exponential distribution under stationary conditions. Using a nonstationary lognormal model, we document the increased complexity and challenges associated with planning for future flood events over a planning horizon. We compare application of the average return period with the more common concept of reliability and recommend replacing the average return period with reliability as a more practical way to communicate event likelihood in both stationary and nonstationary contexts.

  5. Periodicity of extinction: A 1988 update

    Science.gov (United States)

    Sepkowski, J. John, Jr.

    1988-01-01

    The hypothesis that events of mass extinction recur periodically at approximately 26 my intervals is an empirical claim based on analysis of data from the fossil record. The hypothesis has become closely linked with catastrophism because several events in the periodic series are associated with evidence of extraterrestrial impacts, and terrestrial forcing mechanisms with long, periodic recurrences are not easily conceived. Astronomical mechanisms that have been hypothesized include undetected solar companions and solar oscillation about the galactic plane, which induce comet showers and result in impacts on Earth at regular intervals. Because these mechanisms are speculative, they have been the subject of considerable controversy, as has the hypothesis of periodicity of extinction. In response to criticisms and uncertainties, a data base was developed on times of extinction of marine animal genera. A time series is given and analyzed with 49 sample points for the per-genus extinction rate from the Late Permian to the Recent. An unexpected pattern in the data is the uniformity of magnitude of many of the periodic extinction events. Observations suggest that the sequence of extinction events might be the result of two sets of mechanisms: a periodic forcing that normally induces only moderate amounts of extinction, and independent incidents or catastrophes that, when coincident with the periodic forcing, amplify its signal and produce major-mass extinctions.

  6. Pétrole, gaz, environnement : quelle approche de la R&D en exploration-production pour la fin du siècle ? Oil, Gas and the Environment: What Approach by R&D in Exploration-Production for the End of the Century?

    Directory of Open Access Journals (Sweden)

    Tissot B.

    2006-11-01

    Full Text Available Cet article rappelle tout d'abord, un constat du XVe Congrès du Conseil Mondial de l'Énergie (Madrid, septembre 1992 : au cours des 30 prochaines années, les énergies fossiles vont continuer à être à la base de tout approvisionnement énergétique . Examinant les conditions de ce maintien dans un contexte géopolitique difficile, il montre qu'une des voies à privilégier est d'accroître les efforts de recherches pour réaliser les progrès scientifiques et technologiques qui permettront de satisfaire la demande en pétrole et en gaz pour le début du 21ème siècle. L'effort de R & D nécessaire pour disposer des technologies pétrolières et gazières de la prochaine décennie nécessite une recherche faite en commun, car seule une recherche coordonnée évitera une dispersion des efforts français. L'élargissement des réserves économiquement exploitables, la maîtrise du coût de production et la réduction des coûts des chaînes gaz des champs de production aux régions consommatrices, tout en assurant la protection de l'environnement sont les prochains défis à relever. Pour faire face à ces attentes de l'industrie, d'importants efforts de recherche doivent être menés dans les domaines scientifiques correspondants, afin de mieux appréhender les phénomènes et de développer les solutions les plus appropriées. En définitive, les progrès scientifiques et technologiques, nécessaires à l'élargissement des réserves économiques exploitables, à une plus grande accessibilité aux ressources pétrolières et gazières, ainsi qu'à une utilisation mieux ciblée de l'énergie face à la protection de l'environnement, demandent un accroissement sensible des efforts de recherche. Une telle politique ne peut se concevoir sans recourir à un partenariat plus large et sans une incitation et un financement substantiel de la part de la puissance publique, française ou européenne. This article begins by recalling a statement made

  7. What is the incubation period for listeriosis?

    Directory of Open Access Journals (Sweden)

    Goulet Véronique

    2013-01-01

    Full Text Available Abstract Background Listeriosis is a foodborne infection with a low incidence but a high case fatality rate. Unlike common foodborne diseases, the incubation period can be long. The first incubation periods were documented during a large listeriosis outbreak published in 1987 by Linnan and al. in the New England Journal of Medicine (range: 3 days to 70 days. Data on the incubation period of listeriosis are scarce. Our study aim was to estimate precisely the incubation period of listeriosis using available data since 1987. Methods We estimated the incubation period of listeriosis using available published data and data from outbreak investigations carried out by the French National Institute for Public Health Surveillance. We selected cases with an incubation period calculated when a patient had a single exposure to a confirmed food source contaminated by Listeria monocytogenes. Results We identified 37 cases of invasive listeriosis (10 cases with central nervous system involvement (CNS cases, 15 bacteraemia cases and 12 pregnancy-associated cases and 9 outbreaks with gastroenteritis. The overall median incubation period of invasive listeriosis was 8 days (range: 1–67 days and differed significantly by clinical form of the disease (p Conclusions This information has implications for the investigation of food borne listeriosis outbreaks as the incubation period is used to determine the time period for which a food history is collected. We believe that, for listeriosis outbreaks, adapting the exposure window for documenting patients’ food histories in accordance with the clinical form of infection will facilitate the identification of food products as the source of contamination. We therefore propose to take an exposure window of 14 days before the diagnosis for CNS and bacteraemia cases, and of 6 weeks before the diagnosis, for pregnancy-associated cases.

  8. Saturn kilometric radiation periodicity after equinox

    Science.gov (United States)

    Fischer, G.; Gurnett, D. A.; Kurth, W. S.; Ye, S.-Y.; Groene, J. B.

    2015-07-01

    The rotation period of Saturn's magnetosphere was found to vary with time, and changing periodicities were identified in magnetic fields, radio emissions, and charged particles. Here we analyze the varying period of Saturn kilometric radiation (SKR) from 2009 to early 2013, i.e. mainly after Saturn equinox of August 2009. A periodicity analysis is first applied to the complete SKR signal, and second to SKR intensities separated by spacecraft latitude and wave polarization, attributed to SKR from the northern and southern hemisphere. Our analyses are done with the tracking filter approach of Gurnett et al. (Gurnett et al. [2009a]. Geophys. Res. Lett. 36, L16102) and by simply tracing the phases of normalized SKR intensity maxima (north and south) with time. It is shown that SKR periods from the northern and southern hemisphere converged during 2009, crossed shortly after equinox, and coalesced in spring 2010. We will show that SKR from both hemispheres not only exhibited similar periods, but also similar phases from March 2010 until February 2011 and from August 2011 until June 2012. The in-between time interval (March to July 2011) shows a slowdown of the southern SKR rotation rate and a slight increase in rotation speed for the northern SKR before rotation rates and phases become equal again in August 2011. We also identify SKR signals where the modulation phase deviation exceeds one rotation each time Cassini completes one orbit, i.e. this is consistent with the characteristic of a rotating signal. However, the main SKR modulation signals from 2009 to 2012 can be viewed as being clock-like with no correction needed for the derived periods. A comparison of SKR periodicities after equinox to the planetary period oscillations of the magnetic field shows major differences, and we compare SKR phases to magnetic field phases to explain the deviations.

  9. Periodic solutions of dissipative systems revisited

    Directory of Open Access Journals (Sweden)

    Górniewicz Lech

    2006-01-01

    Full Text Available We reprove in an extremely simple way the classical theorem that time periodic dissipative systems imply the existence of harmonic periodic solutions, in the case of uniqueness. We will also show that, in the lack of uniqueness, the existence of harmonics is implied by uniform dissipativity. The localization of starting points and multiplicity of periodic solutions will be established, under suitable additional assumptions, as well. The arguments are based on the application of various asymptotic fixed point theorems of the Lefschetz and Nielsen type.

  10. Periodic solutions of dissipative systems revisited

    Directory of Open Access Journals (Sweden)

    Lech Górniewicz

    2006-05-01

    Full Text Available We reprove in an extremely simple way the classical theorem that time periodic dissipative systems imply the existence of harmonic periodic solutions, in the case of uniqueness. We will also show that, in the lack of uniqueness, the existence of harmonics is implied by uniform dissipativity. The localization of starting points and multiplicity of periodic solutions will be established, under suitable additional assumptions, as well. The arguments are based on the application of various asymptotic fixed point theorems of the Lefschetz and Nielsen type.

  11. Diffraction Theory and Almost Periodic Distributions

    Science.gov (United States)

    Strungaru, Nicolae; Terauds, Venta

    2016-09-01

    We introduce and study the notions of translation bounded tempered distributions, and autocorrelation for a tempered distribution. We further introduce the spaces of weakly, strongly and null weakly almost periodic tempered distributions and show that for weakly almost periodic tempered distributions the Eberlein decomposition holds. For translation bounded measures all these notions coincide with the classical ones. We show that tempered distributions with measure Fourier transform are weakly almost periodic and that for this class, the Eberlein decomposition is exactly the Fourier dual of the Lebesgue decomposition, with the Fourier-Bohr coefficients specifying the pure point part of the Fourier transform. We complete the project by looking at few interesting examples.

  12. Periodicity effects on compound guided waves

    Science.gov (United States)

    Chiadini, Francesco; Fiumara, Vincenzo; Scaglione, Antonio; Lakhtakia, Akhlesh

    2016-09-01

    Surface waves of different types can be compounded when a homogeneous layer is sandwiched between two half spaces filled with dissimilar periodically non-homogeneous dielectric materials and the intermediate layer is sufficiently thin. We solved the boundary-value problem for compound waves guided by a layer of a homogeneous and isotropic (metal or dielectric) material sandwiched between a structurally chiral material (SCM) and a periodically multi-layered isotropic dielectric material. We found that the periodicity of the SCM is crucial to excite a multiplicity of compound guided waves with strong coupling between the two interfaces.

  13. Investigation of periodic Ni–Ti multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Veres, T., E-mail: veres.tamas@wigner.mta.hu [Wigner Research Centre for Physics, Institute for Solid State Physics and Optics, Budapest H-1121, Konkoly-Thege út 29.-33. (Hungary); Cser, L. [Wigner Research Centre for Physics, Institute for Solid State Physics and Optics, Budapest H-1121, Konkoly-Thege út 29.-33. (Hungary); Bodnarchuck, V.; Ignatovich, V. [Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, Joliot-Curie st. 6, Dubna, Moscow Reg. 141980 (Russian Federation); Horváth, Z.E. [Research Centre for Natural Sciences, Institute for Technical Physics and Materials Science, Budapest H-1121, Konkoly-Thege út 29.-33. (Hungary); Nagy, B. [Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, Budapest H-1121, Konkoly-Thege út 29.-33. (Hungary)

    2013-07-01

    In order to improve the quality of neutron supermirrors periodic multilayers of various periods were prepared. The reflectivity properties of these systems were investigated using neutron and X-ray reflectometry. The obtained experimental results were compared with the calculated ones. The deviations from the proposed structure and calculated scattering length densities were investigated. In first approximation, the results proved the main features of the calculations. The roughness of different interfaces was also investigated. - Highlights: • Periodic Ni(Mo)/Ti multilayer samples were prepared by dc sputtering. • X-ray and neutron reflectivity measurements on the samples • Fitting and comparison with the proposed structure.

  14. Numerical bifurcation of Hamiltonian relative periodic orbits

    DEFF Research Database (Denmark)

    Wulff, Claudia; Schilder, Frank

    2009-01-01

    that the family of choreographies rotating around the $e^2$-axis bifurcates to the family of rotating choreographies that connects to the Lagrange relative equilibrium. Moreover, we compute several relative period-doubling bifurcations and a turning point of the family of planar rotating choreographies, which...... to symmetry-breaking/symmetry-increasing pitchfork bifurcations or to period-doubling/period-halving bifurcations. We apply our methods to the family of rotating choreographies which bifurcate from the famous figure eight solution of the three-body problem as angular momentum is varied. We find...

  15. The Jovian period in the Sun?

    Science.gov (United States)

    Kotov, V. A.

    2015-09-01

    The 41-year measurements of the Doppler effect of the photosphere performed at the Crimean Astrophysical Observatory, discovered two periods of global oscillations of the Sun: 9600.606(12) s and 9597.929(15) s. Their beat period, 398.4(2.9) d, well agrees with a synodic orbital period of Jupiter, PJ = 398.9 d, raising a new problem for solar physics, cosmogony and cosmology. A hypothesis is advanced that the PJ beating of the Sun is induced by gravitation of Jupiter, revolving in a privileged reference system "the Sun - the Earth".

  16. Variable-Period Undulators for Synchrotron Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Shenoy, Gopal; Lewellen, John; Shu, Deming; Vinokurov, Nikolai

    2005-02-22

    A new and improved undulator design is provided that enables a variable period length for the production of synchrotron radiation from both medium-energy and high energy storage rings. The variable period length is achieved using a staggered array of pole pieces made up of high permeability material, permanent magnet material, or an electromagnetic structure. The pole pieces are separated by a variable width space. The sum of the variable width space and the pole width would therefore define the period of the undulator. Features and advantages of the invention include broad photon energy tunability, constant power operation and constant brilliance operation.

  17. DEVELOPMENT OF RASASASTRA IN MEDIEVAL PERIOD*

    Science.gov (United States)

    Sharma, Harishankar

    1985-01-01

    The paper deals with the historical development of Rasasastra in Medieval period. Knowledge of Rasa has been in existence from the time immemorial. Exploration of natural resources for the benefit of human beings is the object of this therapy. It is a medical science recognized during vedic periods for the betterment of even Devas. Medieval period can be treated as a golden age for the development of this science. Looking at its aim and objects, methodology and therapeutics, it was recognized as a medical science with an independent philosophical background in 14th century, by Madhavacharya in his Sarva Darsana Samgraha. PMID:22557472

  18. Period change in Magellanic Cloud Cepheids

    Energy Technology Data Exchange (ETDEWEB)

    Deasy, H.P.; Wayman, P.A. (Dunsink Observatory, Castleknock (Ireland))

    1985-01-15

    The data for period change in some 115 Cepheid variable stars in the Magellanic Clouds are presented. The accuracy of each determination is estimated and for all but three of the stars it is possible to estimate whether the rate of change of period prior to 1966/67 is maintained subsequently. About 40 per cent of the stars show period variations, similar to the percentage estimated for galactic Cepheids by a previous author. About half of these variations cannot be regarded as being constant in rate.

  19. Weight effects on the periodic ambiguity function

    Science.gov (United States)

    Getz, Benjamin; Levanon, Nadav

    1995-01-01

    CW radar signals and processors are discussed. The use of the periodic ambiguity function (PAF) to analyze the delay-Doppler performance of CW signals and their corresponding correlation receivers, is extended to include weight function effects. This work provides tools which can predict the delay-Doppler response of almost any phase-coded CW radar. Examples demonstrate that a combination of CW signals having perfect periodic autocorrelation, a matched reference signal with a large number of modulation periods and a smooth weight function, can create a delay-Doppler response with extremely low sidelobes, strongly resembling the response of a coherent pulse train.

  20. Periodic orbits of planets in binary systems

    Science.gov (United States)

    Voyatzis, G.

    2017-03-01

    Periodic solutions of the three body problem are very important for understanding its dynamics either in a theoretical framework or in various applications in celestial mechanics. In this paper we discuss the computation and continuation of periodic orbits for planetary systems. The study is restricted to coplanar motion. Starting from known results of two-planet systems around single stars, we perform continuation of solutions with respect to the mass and approach periodic orbits of single planets in two-star systems. Also, families of periodic solutions can be computed for fixed masses of the primaries. When they are linearly stable, we can conclude about the existence of phase space domains of long-term orbital stability.