Solutions to operate transmission and distribution gas networks

Directory of Open Access Journals (Sweden)

Neacsu Sorin

2017-01-01

Full Text Available In order to respect the actual and future regulations, besides SCADA, there is a need for further modern operating solutions for the transmission and distribution gas network. The paper presents the newest operating principles and modern software solutions that represent a considerable help to operate the transmission and distribution gas networks.

Comparative QRA (Quantitative Risk Analysis) of natural gas distribution pipelines in urban areas; Analise comparativa dos riscos da operacao de linhas de gas natural em areas urbanas

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Luiz Fernando S. de [Energy Solutions South America (Brazil); Cardoso, Cassia de O.; Storch, Rafael [Det Norske Veritas (DNV) (Brazil)

2008-07-01

The natural gas pipeline network grows around the world, but its operation inherently imposes a risk to the people living next to pipelines. Due to this, it is necessary to conduct a risk analysis during the environmental licensing in Brazil. Despite the risk analysis methodology is well established, some points of its application for the distribution pipelines are still under discussion. This paper presents a methodology that examines the influences of major projects and operating parameters on the risk calculation of a distribution pipeline accident in urban areas as well as the possible accident scenarios assessment complexity. The impact of some scenarios has been evaluated using a Computational Fluid Dynamics tool. The results indicate that, under certain conditions, the risks from the pipeline operation under operating pressures of 20 bar may be acceptable in location class 3 or even in class 4. These results play a very important role if management decisions on the growth of the distribution of natural gas network in densely populated areas as well as in the improvement of laws to control the activity of distribution of natural gas. (author)

Estimating Predictive Variance for Statistical Gas Distribution Modelling

International Nuclear Information System (INIS)

Lilienthal, Achim J.; Asadi, Sahar; Reggente, Matteo

2009-01-01

Recent publications in statistical gas distribution modelling have proposed algorithms that model mean and variance of a distribution. This paper argues that estimating the predictive concentration variance entails not only a gradual improvement but is rather a significant step to advance the field. This is, first, since the models much better fit the particular structure of gas distributions, which exhibit strong fluctuations with considerable spatial variations as a result of the intermittent character of gas dispersal. Second, because estimating the predictive variance allows to evaluate the model quality in terms of the data likelihood. This offers a solution to the problem of ground truth evaluation, which has always been a critical issue for gas distribution modelling. It also enables solid comparisons of different modelling approaches, and provides the means to learn meta parameters of the model, to determine when the model should be updated or re-initialised, or to suggest new measurement locations based on the current model. We also point out directions of related ongoing or potential future research work.

Long-lived gas-phase radicals from combustion

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Takashi; Furusawa, Koji; Amano, Toshiji; Okubo, Yoichi; Tsuchiya, Jun' ichi; Yoshizawa, Fujiroku; Akutsu, Yoshiaki; Tamura, Masamitsu; Yoshida, Tadao (Univ. of Tokyo (Japan))

1989-04-20

On indoor air pollution or fire, it is feared that the gas-phase radicals from the combustion of inflammables or fuel seriously exert an influence on the organisms as harmful matter. The gas-phase radicals were studied using the electron spin resonance (ESR) spin-trapping technique. For the spin trap solution, 0.1 mol solution of {alpha}-phenyl-N-t-butylnitron in benzene was used. As a result, apparently long-lived and highly reactive oxygen-centered radicals were detected in the smoke from polyethylene, polypropylene, polystyrene, polymethylmethacrylate, cellulose, kerosene, benzene, acetone, methanol and butylalcohol. It is suggested that the production mechanism for the radicals should be different from olefin-NOx-air system reaction, which is considered for the radicals from cigarette smoke. 11 refs., 6 figs., 2 tabs.

Biogas in the natural gas distribution network; Biogas til nettet

Energy Technology Data Exchange (ETDEWEB)

Kvist Jensen, T.

2009-05-15

With the Danish 'Thorsoe Biogas Plant' as reference case, an assessment of the possibility of using the existing natural gas distribution network for distributing biogas was carried out. Technologies for and cost of upgrading biogas to natural gas quality are presented. Furthermore, a socio-economic analysis has been performed, including the Danish financial conditions, the market models, and the role of the natural gas distribution companies.

Natural gas distribution network of Lima and Callao, Peru

Energy Technology Data Exchange (ETDEWEB)

Maroye, Stephane; Aerssens, Andre [Tractebel Engineering, Lima (Peru)

2005-07-01

In May 2002, Suez-Tractebel was awarded by the government of Peru a 30-year concession for the construction and operation of the gas distribution network in Lima, Peru. On 10 July, 2004, first gas was delivered to Lima, 1 month ahead of the official date. This gas distribution network, operated by GNLC (Gas Natural de Lima y Callao), delivers gas to some of the largest industries and power generators in and around Lima and the harbour area of Callao. Gas delivered in Lima comes through a 700 km HP gas pipeline from Camisea fields. This pipeline is operated by TGP (Transportadora de Gas del Peru). A City Gate is located at Lurin, on the southern side of the city. The gas distribution network is made of a 62 km main pipeline (20') with 25 km laterals. The main pipeline is operated at 50 bar, as the main customer, the Etevensa power plant, is located on the northern side of the city. Due to this high operating pressure combined to the surroundings, specific design philosophies were adopted to meet the extreme safety requirements. This paper highlights the specific measures taken during construction phase and the experience of the first months of operation of this challenging project. (author)

Vertical distribution of living mangrove foraminifera from KwaZulu ...

African Journals Online (AJOL)

Previous intertidal foraminiferal studies have predominantly focused on assemblages in surface sediments (0–1 cm), with the rationale that surface assemblages reflect the modern-day environment. Foraminifera live infaunally and therefore there is a need to document the infaunal vertical distribution of living foraminifera to ...

Geologic distributions of US oil and gas

International Nuclear Information System (INIS)

1992-01-01

This publication presents nonproprietary field size distributions that encompass most domestic oil and gas fields at year-end 1989. These data are organized by geologic provinces as defined by the American Association of Petroleum Geologists' Committee on Statistics of Drilling (AAPG/CSD), by regional geographic aggregates of the AAPG/CSD provinces, and Nationally. The report also provides partial volumetric distributions of petroleum liquid and natural gas ultimate recoveries for three macro-geologic variables: principal lithology of the reservoir rock, principal trapping condition and geologic age of the reservoir rock, The former two variables are presented Nationally and by geographic region, in more detail than has heretofore been available. The latter variable is provided Nationally at the same level of detail previously available. Eighteen tables and 66 figures present original data on domestic oil and gas occurrence. Unfortunately, volumetric data inadequacy dictated exclusion of Appalachian region oil and gas fields from the study. All other areas of the United States known to be productive of crude oil or natural gas through year-end 1989, onshore and offshore, were included. It should be noted that none of the results and conclusions would be expected to substantively differ had data for the Appalachian region been available for inclusion in the study

Gas turbine control for islanding operation of distribution systems

DEFF Research Database (Denmark)

Mahat, Pukar; Chen, Zhe; Bak-Jensen, Birgitte

2009-01-01

Danish distribution systems are characterized by a significant penetration of small gas turbine generators (GTGs) and fixed speed wind turbine generators (WTGs). Island operation of these distribution systems are becoming a viable option for economical and technical reasons. However, stabilizing...... frequency in an islanded system is one of the major challenges. This paper presents three different gas turbine governors for possible operation of distribution systems in an islanding mode. Simulation results are presented to show the performance of these governors in grid connected and islanding mode....

Long-Range Untethered Real-Time Live Gas Main Robotic Inspection System

Energy Technology Data Exchange (ETDEWEB)

Hagen Schempf; Daphne D' Zurko

2004-10-31

Under funding from the Department of Energy (DOE) and the Northeast Gas Association (NGA), Carnegie Mellon University (CMU) developed an untethered, wireless remote controlled inspection robot dubbed Explorer. The project entailed the design and prototyping of a wireless self-powered video-inspection robot capable of accessing live 6- and 8-inch diameter cast-iron and steel mains, while traversing turns and Ts and elbows under real-time control with live video feedback to an operator. The design is that of a segmented actively articulated and wheel-leg powered robot design, with fisheye imaging capability and self-powered battery storage and wireless real-time communication link. The prototype was functionally tested in an above ground pipe-network, in order to debug all mechanical, electrical and software subsystems, and develop the necessary deployment and retrieval, as well as obstacle-handling scripts. A pressurized natural gas test-section was used to certify it for operation in natural gas at up to 60 psig. Two subsequent live-main field-trials in both cast-iron and steel pipe, demonstrated its ability to be safely launched, operated and retrieved under real-world conditions. The system's ability to safely and repeatably exidrecover from angled and vertical launchers, traverse multi-thousand foot long pipe-sections, make T and varied-angle elbow-turns while wirelessly sending live video and handling command and control messages, was clearly demonstrated. Video-inspection was clearly shown to be a viable tool to understand the state of this critical buried infrastructure, irrespective of low- (cast-iron) or high-pressure (steel) conditions. This report covers the different aspects of specifications, requirements, design, prototyping, integration and testing and field-trialing of the Explorer platform.

Expert hierarchical selection of oil and gas distribution systems

International Nuclear Information System (INIS)

Frankel, E.G.

1991-01-01

Selection and design of oil and gas distribution systems involves a large number of decision makers and interest groups, as well as many alternative technical, financial, network, operating, management and regulatory options. Their objectives and measures of performance are different. Decision models can be effectively represented by hierarchical structures. A simple deterministic analytic hierarchy process is presented with application to oil and gas distribution systems

Security resolution minute for natural gas distribution pipeline; Minuta de resolucao de seguranca na distribuicao do gas natural

Energy Technology Data Exchange (ETDEWEB)

Teles, Marcus de Barros [ARCE - Agencia Reguladora de Servicos Publicos Delegados do Estado do Ceara, Fortaleza, CE (Brazil)

2003-07-01

In the current scenery of natural gas distribution regulation, there is no specific resolution about security. The security is boarded in few concession contracts of some private gas companies, but not as principal theme. The security resolution minute presented in this paper aim break the direct and indirect causes of accidents, eliminating their potential. In this new point of view, the quality of services is the principal cause to guarantee the security of natural gas distribution systems. The methodology used to develop the minute was based on the research of Brazilian and American resolutions of state regulation agencies, concession contracts of private distribution gas companies, American code of federal regulation, ASME code for pressure piping B31.8 - 1999 edition and the NBR 12712 standard. The result of the research was the elaboration of an specific minute resolution of security that can be used as reference in the fiscalization of the natural gas distribution piping companies activities. This minute, can be an important instrument to avoid accidents and incidents, eliminating prejudices to the people, to properties, to environment and to the image of natural gas distribution companies and regulation agencies. (author)

Gas-Fired Distributed Energy Resource Technology Characterizations

Energy Technology Data Exchange (ETDEWEB)

Goldstein, L.; Hedman, B.; Knowles, D.; Freedman, S. I.; Woods, R.; Schweizer, T.

2003-11-01

The U. S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) is directing substantial programs in the development and encouragement of new energy technologies. Among them are renewable energy and distributed energy resource technologies. As part of its ongoing effort to document the status and potential of these technologies, DOE EERE directed the National Renewable Energy Laboratory to lead an effort to develop and publish Distributed Energy Technology Characterizations (TCs) that would provide both the department and energy community with a consistent and objective set of cost and performance data in prospective electric-power generation applications in the United States. Toward that goal, DOE/EERE - joined by the Electric Power Research Institute (EPRI) - published the Renewable Energy Technology Characterizations in December 1997.As a follow-up, DOE EERE - joined by the Gas Research Institute - is now publishing this document, Gas-Fired Distributed Energy Resource Technology Characterizations.

Land based use of natural gas - distribution solutions

International Nuclear Information System (INIS)

Jordanger, Einar; Moelnvik, Mona J.; Owren, Geir; Einang, Per Magne; Grinden, Bjoern; Tangen, Grethe

2002-05-01

The report presents results from the project ''Landbasert bruk av naturgass - distribusjonsloesninger'' (Land based use of natural gas - distribution solutions). It describes the aims of the project, the political external conditions for the use of natural gas, some environmental profits by changing from petroleum and coal to natural gas, the Norwegian infrastructure, the optimisation of energy transport, strategic consequences of the introduction of LNG and the practical consequences of the Enova strategy

Logistical management system for natural gas distribution; Sistema de gestao logistica para a distribuicao de gas natural

Energy Technology Data Exchange (ETDEWEB)

Arruda, Joao Bosco F; Nobre, Junior, Ernesto F; Praca, Eduardo R [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Nucleo de Pesquisa em Logistica, Transportes e Desenvolvimento

2004-07-01

The Brazilian Federal Government has the very purpose of increasing the participation of the Natural Gas in the primary energy internal supply from 7,5% nowadays to about 12% till 2010. However, for that, it is necessary to eliminate the great impedance represented by the restricted accessibility to the product, due to the high distribution costs involved. So, there is an urgent need for availability of technologies to help natural gas distribution systems. This paper proposes an innovative logistics-based approach on the subject of the natural gas distribution, through a computational tool (GASLOG System) to be applied in the North and Northeastern urban and country areas of Brazil, with initial case study in the city of Fortaleza. In its conception, the GASLOG System focuses on the point-of-view of everyone of the actors involved with the natural gas distribution process trying to respond their particular necessities in the sector. (author)

Gas bubble disease in the brain of a living California sea lion (Zalophus californianus

Directory of Open Access Journals (Sweden)

William George Van Bonn

2013-01-01

Full Text Available A yearling California sea lion (Zalophus californianus was admitted into rehabilitation with signs of cerebellar pathology. Diagnostic imaging that included radiography and magnetic resonance imaging (MRI demonstrated space-occupying lesions predominantly in the cerebellum that were filled partially by CSF-like fluid and partially by gas, and cerebral lesions that were fluid filled. Over a maximum period of four months, the brain lesions reduced in size and the gas resorbed and was replaced by CSF-like fluid. To test the animal in this study for motor memory deficits, an alternation task in a two-choice maze was utilized. The sea lion performed poorly similar to another case of pneumocerebellum previously reported, and contrary to data acquired from a group of sea lions with specific hippocampal injury. The learning deficits were attributed to the cerebellar injury. These data provide important insight both to the clinical presentation and behavioral observations of cerebellar injury in sea lions, as well as providing an initial model for long-term outcome following cerebellar injury. The specific etiology of the gas could not be determined. The live status of the patient with recovery suggests that the most likely etiologies for the gas are either de novo formation or air emboli secondary to trauma. A small air gun pellet was present within and was removed from soft tissues adjacent to the tympanic bulla. While no evidence to support the pellet striking bone was found, altered dive pattern associated with this human interaction may have provided the opportunity for gas bubble formation to occur. The similarity in distribution of the gas bubble related lesions in this case compared with another previously published case of pneumocerebellum suggests that preferential perfusion of the brain, and more specifically the cerebellum, may occur during diving events.

N2 gas station and gas distribution system for TLD personnel monitoring gas based semi-automatic badge readers

International Nuclear Information System (INIS)

Chourasiya, G.; Pradhan, S.M.; Kher, R.K.; Bhatt, B.C

2003-01-01

Full text: New improvised hot gas based Auto TLD badge reader has several advantages over the earlier contact heating based manual badge reader. It requires constant supply of N 2 gas for its operation; The gas supplied using replaceable individual gas cylinders may have some safety hazards in their handling. It was therefore considered worthwhile to setup a N 2 gas assembly/ station outside the lab area and to bring regulated gas supply through network of tubes with proper regulation to the individual readers. The paper presents detailed description of the gas station and distribution system. The system is quite useful and offers several practical advantages for readout of TLD badges on the semiautomatic badge readers based on gas heating. Important advantage from dosimetric point of view is avoidance of gas flow rate fluctuations and corresponding variations in TL readouts

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

Energy Technology Data Exchange (ETDEWEB)

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

2008-07-01

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

World Gas Conference 1997. Working committee D. Distribution of gases

International Nuclear Information System (INIS)

1997-01-01

This volume deals with the work undertaken by Committee D during the Triennium 1994-1997. The subjects relating to gas distribution studied in this volume are as follows: Cost Management; Safety; Human Resource Development; Emerging Systems and General Subjects. Surveys were also conducted on these subjects and results included. Other gas distribution subjects are being addressed during the poster session. (EG)

The welfare effects of unbundling gas storage and distribution

International Nuclear Information System (INIS)

Breton, Michele; Kharbach, Mohammed

2008-01-01

We use a stylized gas system to study the use of access-to-gas storage in a seasonal model. In a duopoly setting, we find that welfare is higher under vertical integration and open access organization than under separate management of storage and distribution. This raises questions about recent regulatory reforms in the gas sectors in the US and Europe, supporting the separation of storage and merchant activities. In the absence of other justifying reasons such as encouraging competition by creating a level playing field, separating the management and accounting functions of storage activities from those of distribution may be a better option than real divestiture, on the basis of welfare arguments. (author)

Review of the use of rigid and high-impact PVC pipes in natural gas distribution systems in the Netherlands

Energy Technology Data Exchange (ETDEWEB)

Mutter, F; Benjamin, P

1974-08-01

Because of a number of instances of stress corrosion cracking or crazing occurring in PVC pipes used in Dutch gas distribution systems, VEG-GASINSTITUUT began an intensive investigation of rigid PVC pipes and high-impact pipes in distribution use under various conditions and with varying service lives. The work led to an investigation of laboratory testing techniques in which the stress-cracking phenomenon found in practice could be duplicated under controllable conditions. Pipes of various materials were examined for their resistance to stress cracking, then this resistance was compared with other long- and short-term physical properties of the material.

LXtoo: an integrated live Linux distribution for the bioinformatics community.

Science.gov (United States)

Yu, Guangchuang; Wang, Li-Gen; Meng, Xiao-Hua; He, Qing-Yu

2012-07-19

Recent advances in high-throughput technologies dramatically increase biological data generation. However, many research groups lack computing facilities and specialists. This is an obstacle that remains to be addressed. Here, we present a Linux distribution, LXtoo, to provide a flexible computing platform for bioinformatics analysis. Unlike most of the existing live Linux distributions for bioinformatics limiting their usage to sequence analysis and protein structure prediction, LXtoo incorporates a comprehensive collection of bioinformatics software, including data mining tools for microarray and proteomics, protein-protein interaction analysis, and computationally complex tasks like molecular dynamics. Moreover, most of the programs have been configured and optimized for high performance computing. LXtoo aims to provide well-supported computing environment tailored for bioinformatics research, reducing duplication of efforts in building computing infrastructure. LXtoo is distributed as a Live DVD and freely available at http://bioinformatics.jnu.edu.cn/LXtoo.

Economic problems of the distribution of gas. Ekonomicheskie problemy raspredeleniya gaza

Energy Technology Data Exchange (ETDEWEB)

Ryps, G S

1978-01-01

Statistical data are presented which characterize the distribution and utilization of gas for the period 1965-1975. Basic trends for gas distribution in the 10th five-year plan up to 1980 are also defined. Principal attention is given to the use of quantitative methods for solving economic problems of gas resource distribution. A method is suggested for solving problems by the use of mathematical modeling wherein the criterion of optimality is the maximum of national economic effectiveness. The systems approach toward the study of the energy-economic phenomenon and the hierarchical principle make it possible to affect an exchange of information between tasks of a variable territorial and sector level. A special chapter is concerned with designing and use of closing outlays for fuel and its refinement products. Examples are given that illustrate the solution of the problem on the distribution of gas and other types of fuels within an economic region. A determination is made of the consistency of gas-line and branch-line construction and the effective depth for the gasification of populated areas. The book is intended for personnel at design-research organizations and economic-planning bodies which are engaged in problems concerned with the distribution of energy carriers. It will also be useful to students at institutions of higher learning. 78 references, 13 figures, 61 tables.

The temperature distribution in a gas core fission reactor

Energy Technology Data Exchange (ETDEWEB)

Hoogenboom, J.E.; Dam, H. van; Kuijper, J.C. (Interuniversitair Reactor Inst., Delft (Netherlands)); Kistemaker, J.; Boersma-Klein, W.; Vitalis, F. (FOM-Instituut voor Atoom-en Molecuulfysica, Amsterdam (Netherlands))

1991-01-01

A model is proposed for the heat transport in a nuclear reactor with gaseous fuel at high temperatures taking into account radiative and kinetic heat transfer. A derivation is given of the equation determining the temperature distribution in a gas core reactor and different numerical solution methods are discussed in detail. Results are presented of the temperature distribution. The influence of the kinetic heat transport and of dissociation of the gas molecules is shown. Also discussed is the importance of the temperature gradient at the reactor wall and its dependence on system parameters. (author).

The temperature distribution in a gas core fission reactor

International Nuclear Information System (INIS)

Hoogenboom, J.E.; Dam, H. van; Kuijper, J.C.; Kistemaker, J.; Boersma-Klein, W.; Vitalis, F.

1991-01-01

A model is proposed for the heat transport in a nuclear reactor with gaseous fuel at high temperatures taking into account radiative and kinetic heat transfer. A derivation is given of the equation determining the temperature distribution in a gas core reactor and different numerical solution methods are discussed in detail. Results are presented of the temperature distribution. The influence of the kinetic heat transport and of dissociation of the gas molecules is shown. Also discussed is the importance of the temperature gradient at the reactor wall and its dependence on system parameters. (author)

On-line gas mixing and multi-channel distribution system

International Nuclear Information System (INIS)

Kalmani, S.D.; Mondal, N.K.; Satyanarayana, B.; Verma, P.; Joshi, Avinash

2009-01-01

In this presentation, we describe a mass-flow controller based on-line gas mixing unit with the multi-channel distribution system. We highlight different aspects such as requirement, design, calibration, control and operation of this system. This unit has the capability to mix up to four different input gases and distribute over 16 output channels. Output in individual channels is controlled accurately by using capillary-based system. At present, we are using this gas mixing unit for prototype of iron calorimeter (ICAL) detector of India-based Neutrino Observatory (INO).

Natural gas distribution in Brazil - opportunities of improvement; Distribuicao de gas natural no pais - oportunidades de melhoria

Energy Technology Data Exchange (ETDEWEB)

Correa, Silvia R. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Quintella, Odair M.; Farias Filho, Jose R. de [Universidade Federal Fluminense, Niteroi, RJ (Brazil)

2005-07-01

Great are the challenges established by the Brazilian Government related to goals to be achieved for the increment of the Natural Gas participation in brazilian energetic matrix, from current 5% to 12%, up to 2010. The enlargement of the distribution infrastructure of the gas (gas-pipelines 'mesh') in Brazil is considered one of the greatest challenges for the growth of the Brazilian market of Natural Gas, accomplishment that involves elevated investments. This paper presents a model of Management System for the good organizational performance of the small Natural Gas Supplying Brazilian Companies focused on criteria of Leadership, Strategies and Plans and Results, established by the Premio TOP Empresarial and by the 'Rumo a Excelencia', held by the 'Progama Qualidade Rio' and 'Fundacao para o Premio Nacional da Qualidade', respectively. The management practices of these companies were reviewed, considering the context of the energetic Brazilian scenario, subjected to the political and operational definitions and uncertainties, the available financial resources, limited or not prioritized, and actual barriers to be surpassed by the Gas Supplying Companies in order to achieve the pre-established government goals for this segment. The implementation of the proposed simplified Model, seen as improvement opportunities for the segment of Natural Gas distribution, will lead the Gas Distribution Companies to a intermediary stage envisioning the real steps towards the excellence of the performance. (author)

Using size distribution analysis to forecast natural gas resources in Asia Pacific

International Nuclear Information System (INIS)

Aguilera, Roberto F.; Ripple, Ronald D.

2011-01-01

Highlights: → We estimate the total endowment of conventional natural gas in Asia Pacific. → Includes volumes in previously unassessed provinces. → Endowment distributed across countries to show where volumes are most likely to be found. → A breakdown between offshore versus onshore resources is also estimated. → We find there is a significant natural gas endowment in the region. -- Abstract: Increasing energy consumption in Asia Pacific will largely be met by fossil fuels. Natural gas production in the region presently ranks behind that of oil and coal. However, the abundance of gas could lead to a significant gas market share increase in the energy mix. The purpose of this paper is to estimate the total endowment of conventional gas in Asia Pacific. This is carried out with a Variable Shape Distribution (VSD) model that forecasts volumes in provinces that have not been previously evaluated. The endowment is then distributed across countries to show where volumes are most likely to be found. A breakdown between offshore versus onshore resources is also estimated. The results of the analysis show there is a significant gas endowment. The estimated distribution across countries and onshore/offshore areas provides insight into the relative economics of gas production, as well as a basis for potential investment decisions. With appropriate energy policies, it may be possible to tap the vast gas potential in Asia Pacific. Considering gas may be the most abundant, inexpensive, and clean fossil fuel, the outcome would be increased energy security and a low carbon economy.

Flue gas recovery system for natural gas combined heat and power plant with distributed peak-shaving heat pumps

International Nuclear Information System (INIS)

Zhao, Xiling; Fu, Lin; Wang, Xiaoyin; Sun, Tao; Wang, Jingyi; Zhang, Shigang

2017-01-01

Highlights: • A flue gas recovery system with distributed peak-shaving heat pumps is proposed. • The system can improve network transmission and distribution capacity. • The system is advantageous in energy saving, emission reduction and economic benefits. - Abstract: District heating systems use distributed heat pump peak-shaving technology to adjust heat in secondary networks of substations. This technology simultaneously adjusts the heat of the secondary network and reduces the return-water temperature of the primary network by using the heat pump principle. When optimized, low temperature return-water is able to recycle more waste heat, thereby further improving the heating efficiency of the system. This paper introduces a flue gas recovery system for a natural gas combined heat and power plant with distributed peak-shaving heat pumps. A pilot system comprising a set of two 9F gas-steam combined cycle-back pressure heating units was used to analyse the system configuration and key parameters. The proposed system improved the network transmission and distribution capacity, increased heating capacity, and reduced heating energy consumption without compromising heating safety issues. As such, the proposed system is advantageous in terms of energy saving, emission reduction, and economic benefits.

Inhomogeneous Oxygen Vacancy Distribution in Semiconductor Gas Sensors: Formation, Migration and Determination on Gas Sensing Characteristics.

Science.gov (United States)

Liu, Jianqiao; Gao, Yinglin; Wu, Xu; Jin, Guohua; Zhai, Zhaoxia; Liu, Huan

2017-08-10

The density of oxygen vacancies in semiconductor gas sensors was often assumed to be identical throughout the grain in the numerical discussion of the gas-sensing mechanism of the devices. In contrast, the actual devices had grains with inhomogeneous distribution of oxygen vacancy under non-ideal conditions. This conflict between reality and discussion drove us to study the formation and migration of the oxygen defects in semiconductor grains. A model of the gradient-distributed oxygen vacancy was proposed based on the effects of cooling rate and re-annealing on semiconductive thin films. The model established the diffusion equations of oxygen vacancy according to the defect kinetics of diffusion and exclusion. We described that the steady-state and transient-state oxygen vacancy distributions, which were used to calculate the gas-sensing characteristics of the sensor resistance and response to reducing gases under two different conditions. The gradient-distributed oxygen vacancy model had the applications in simulating the sensor performances, such as the power law, the grain size effect and the effect of depletion layer width.

Inhomogeneous Oxygen Vacancy Distribution in Semiconductor Gas Sensors: Formation, Migration and Determination on Gas Sensing Characteristics

Directory of Open Access Journals (Sweden)

Jianqiao Liu

2017-08-01

Full Text Available The density of oxygen vacancies in semiconductor gas sensors was often assumed to be identical throughout the grain in the numerical discussion of the gas-sensing mechanism of the devices. In contrast, the actual devices had grains with inhomogeneous distribution of oxygen vacancy under non-ideal conditions. This conflict between reality and discussion drove us to study the formation and migration of the oxygen defects in semiconductor grains. A model of the gradient-distributed oxygen vacancy was proposed based on the effects of cooling rate and re-annealing on semiconductive thin films. The model established the diffusion equations of oxygen vacancy according to the defect kinetics of diffusion and exclusion. We described that the steady-state and transient-state oxygen vacancy distributions, which were used to calculate the gas-sensing characteristics of the sensor resistance and response to reducing gases under two different conditions. The gradient-distributed oxygen vacancy model had the applications in simulating the sensor performances, such as the power law, the grain size effect and the effect of depletion layer width.

Gas-leak localization using distributed ultrasonic sensors

Science.gov (United States)

Huseynov, Javid; Baliga, Shankar; Dillencourt, Michael; Bic, Lubomir; Bagherzadeh, Nader

2009-03-01

We propose an ultrasonic gas leak localization system based on a distributed network of sensors. The system deploys highly sensitive miniature Micro-Electro-Mechanical Systems (MEMS) microphones and uses a suite of energy-decay (ED) and time-delay of arrival (TDOA) algorithms for localizing a source of a gas leak. Statistical tools such as the maximum likelihood (ML) and the least squares (LS) estimators are used for approximating the source location when closed-form solutions fail in the presence of ambient background nuisance and inherent electronic noise. The proposed localization algorithms were implemented and tested using a Java-based simulation platform connected to four or more distributed MEMS microphones observing a broadband nitrogen leak from an orifice. The performance of centralized and decentralized algorithms under ED and TDOA schemes is analyzed and compared in terms of communication overhead and accuracy in presence of additive white Gaussian noise (AWGN).

Distributed gas detection system and method

Science.gov (United States)

Challener, William Albert; Palit, Sabarni; Karp, Jason Harris; Kasten, Ansas Matthias; Choudhury, Niloy

2017-11-21

A distributed gas detection system includes one or more hollow core fibers disposed in different locations, one or more solid core fibers optically coupled with the one or more hollow core fibers and configured to receive light of one or more wavelengths from a light source, and an interrogator device configured to receive at least some of the light propagating through the one or more solid core fibers and the one or more hollow core fibers. The interrogator device is configured to identify a location of a presence of a gas-of-interest by examining absorption of at least one of the wavelengths of the light at least one of the hollow core fibers.

Gas Bubble Disease in the Brain of a Living California Sea Lion (Zalophus californianus).

Science.gov (United States)

Van Bonn, William; Dennison, Sophie; Cook, Peter; Fahlman, Andreas

2013-01-01

A yearling California sea lion (Zalophus californianus) was admitted into rehabilitation with signs of cerebellar pathology. Diagnostic imaging that included radiography and magnetic resonance imaging (MRI) demonstrated space-occupying lesions predominantly in the cerebellum that were filled partially by CSF-like fluid and partially by gas, and cerebral lesions that were fluid filled. Over a maximum period of 4 months, the brain lesions reduced in size and the gas resorbed and was replaced by CSF-like fluid. In humans, the cerebellum is known to be essential for automating practiced movement patterns (e.g., learning to touch-type), also known as procedural learning or the consolidation of "motor memory." To test the animal in this study for motor memory deficits, an alternation task in a two-choice maze was utilized. The sea lion performed poorly similar to another case of pneumocerebellum previously reported, and contrary to data acquired from a group of sea lions with specific hippocampal injury. The learning deficits were attributed to the cerebellar injury. These data provide important insight both to the clinical presentation and behavioral observations of cerebellar injury in sea lions, as well as providing an initial model for long-term outcome following cerebellar injury. The specific etiology of the gas could not be determined. The live status of the patient with recovery suggests that the most likely etiologies for the gas are either de novo formation or air emboli secondary to trauma. A small air gun pellet was present within and was removed from soft tissues adjacent to the tympanic bulla. While no evidence to support the pellet striking bone was found, altered dive pattern associated with this human interaction may have provided the opportunity for gas bubble formation to occur. The similarity in distribution of the gas bubble related lesions in this case compared with another previously published case of pneumocerebellum suggests that preferential

Risk analysis for a local gas distribution network

International Nuclear Information System (INIS)

Peters, J.W.

1991-01-01

Cost control and service reliability are popular topics when discussing strategic issues facing local distribution companies (LDCs) in the 1990s. The ability to provide secure and uninterrupted gas service is crucial for growth and company image, both with the public and regulatory agencies. At the same time, the industry is facing unprecedented competition from alternate fuels, and cost control is essential for maintaining a competitive edge in the market. On the surface, it would appear that cost control and service reliability are contradictory terms. Improvement in service reliability should cost something, or does it? Risk analysis can provide the answer from a distribution design perspective. From a gas distribution engineer's perspective, projects such as loops, backfeeds and even valve placement are designed to reduce, minimize and/or eliminate potential customer outages. These projects improve service reliability by acting as backups should a failure occur on a component of the distribution network. These contingency projects are cost-effective but their longterm benefit or true value is under question. Their purpose is to maintain supply to an area in the distribution network in the event of a failure somewhere else. Two phrases, potential customer outages and in the event of failure, identify uncertainty

Distributed gas sensing with optical fibre photothermal interferometry.

Science.gov (United States)

Lin, Yuechuan; Liu, Fei; He, Xiangge; Jin, Wei; Zhang, Min; Yang, Fan; Ho, Hoi Lut; Tan, Yanzhen; Gu, Lijuan

2017-12-11

We report the first distributed optical fibre trace-gas detection system based on photothermal interferometry (PTI) in a hollow-core photonic bandgap fibre (HC-PBF). Absorption of a modulated pump propagating in the gas-filled HC-PBF generates distributed phase modulation along the fibre, which is detected by a dual-pulse heterodyne phase-sensitive optical time-domain reflectometry (OTDR) system. Quasi-distributed sensing experiment with two 28-meter-long HC-PBF sensing sections connected by single-mode transmission fibres demonstrated a limit of detection (LOD) of ∼10 ppb acetylene with a pump power level of 55 mW and an effective noise bandwidth (ENBW) of 0.01 Hz, corresponding to a normalized detection limit of 5.5ppb⋅W/Hz. Distributed sensing experiment over a 200-meter-long sensing cable made of serially connected HC-PBFs demonstrated a LOD of ∼ 5 ppm with 62.5 mW peak pump power and 11.8 Hz ENBW, or a normalized detection limit of 312ppb⋅W/Hz. The spatial resolution of the current distributed detection system is limited to ∼ 30 m, but it is possible to reduce down to 1 meter or smaller by optimizing the phase detection system.

Estimation of current density distribution of PAFC by analysis of cell exhaust gas

Energy Technology Data Exchange (ETDEWEB)

Kato, S.; Seya, A. [Fuji Electric Co., Ltd., Ichihara-shi (Japan); Asano, A. [Fuji Electric Corporate, Ltd., Yokosuka-shi (Japan)

1996-12-31

To estimate distributions of Current densities, voltages, gas concentrations, etc., in phosphoric acid fuel cell (PAFC) stacks, is very important for getting fuel cells with higher quality. In this work, we leave developed a numerical simulation tool to map out the distribution in a PAFC stack. And especially to Study Current density distribution in the reaction area of the cell, we analyzed gas composition in several positions inside a gas outlet manifold of the PAFC stack. Comparing these measured data with calculated data, the current density distribution in a cell plane calculated by the simulation, was certified.

Pore size distribution effect on rarefied gas transport in porous media

Science.gov (United States)

Hori, Takuma; Yoshimoto, Yuta; Takagi, Shu; Kinefuchi, Ikuya

2017-11-01

Gas transport phenomena in porous media are known to strongly influence the performance of devices such as gas separation membranes and fuel cells. Knudsen diffusion is a dominant flow regime in these devices since they have nanoscale pores. Many experiments have shown that these porous media have complex structures and pore size distributions; thus, the diffusion coefficient in these media cannot be easily assessed. Previous studies have reported that the characteristic pore diameter of porous media can be defined in light of the pore size distribution; however, tortuosity factor, which is necessary for the evaluation of diffusion coefficient, is still unknown without gas transport measurements or simulations. Thus, the relation between pore size distributions and tortuosity factors is required to obtain the gas transport properties. We perform numerical simulations to prove the relation between them. Porous media are numerically constructed while satisfying given pore size distributions. Then, the mean-square displacement simulation is performed to obtain the tortuosity factors of the constructed porous media.. This paper is based on results obtained from a project commissioned by the New Energy and Industrial Development Organization (NEDO).

[Live birth distribution by time and place from 1981 to 1998 in Japan].

Science.gov (United States)

Matsushima, Noriko; Morita, Noriko; Ogata, Nozomi; Saeki, Keigo; Matsuda, Ryozo; Kurumatani, Norio

2003-01-01

To investigate the diurnal rhythm of live births labored spontaneously, and the effects of obstetric intervention on birth time distributions. The data of live births tabulated by time (one-hour intervals), date and birthplace throughout Japan between 1981 and 1998 were obtained with permission from the former Ministry of Health and Welfare. Together with an investigation of hourly birth numbers by place in each year, an annual transition of hourly birth rates in medical institutions and the diurnal rhythm of birth numbers in maternity homes and at home were analyzed using regression analysis. In every calendar year studied the hourly live birth numbers at hospitals showed a single-peak distribution pattern with maximum values at 13:00-15:00. The annual transition of hourly birth rates showed a 10% (birth numbers base) decrease in the 11:00-13:00 period in 1998 as compared with that in 1981, while there was a corresponding increase of 8% in the 13:00-15:00 period. Hourly birth numbers at clinics showed a double-peak distribution pattern with maximum values during the 11:00-12:00 and 14:00-15:00 periods in early 1980, while a single-peak distribution with a maximum value during the 13:00-15:00 period appeared in 1989 and has remained thereafter. Hourly birth rates (birth numbers base) increased by over 6% in the 13:00-15:00 and 17:00-20:00 periods over the past 18 years, while they decreased by 10% in the 9:00-13:00 period. The results at maternity homes were clearly different from those at hospitals and clinics. The live birth numbers totaled for the 18 years showed a double-phase distribution with a maximum value in the 6:00-7:00 period and a minimum value in the 19:00-20:00 period. The best-fit regression model for the obtained data was a sine curve with a maximum value at 6:00 (coefficient of determination 0.97). Hourly distributions of live births at home also fitted best to a since curve with the maximum value again at 6:00 (coefficient of determination 0

Effect of overpressure on gas hydrate distribution

Energy Technology Data Exchange (ETDEWEB)

Bhatnagar, G.; Chapman, W.G.; Hirasaki, G.J. [Rice Univ., Houston, TX (United States). Dept. of Chemical and Biomolecular Engineering; Dickens, G.R.; Dugan, B. [Rice Univ., Houston, TX (United States). Dept. of Earth Sciences

2008-07-01

Natural gas hydrate systems can be characterized by high sedimentation rates and/or low permeability sediments, which can lead to pore pressure higher than hydrostatic. This paper discussed a study that examined this effect of overpressure on gas hydrate and free gas distribution in marine sediments. A one-dimensional numerical model that coupled sedimentation, fluid flow, and gas hydrate formation was utilized. In order to quantify the relative importance of sedimentation rates and low permeability sediments, a dimensionless sedimentation-compaction group (scN) was defined, that compared the absolute permeability of the sediments to the sedimentation rate. Higher values of scN mean higher permeability or low sedimentation rate which generally yield hydrostatic pore pressure while lower values of scN normally create pore pressure greater than hydrostatic. The paper discussed non-hydrostatic consolidation in gas hydrate systems, including mass balances; constitutive relationships; normalized variables; and dimensionless groups. A numerical solution to the problem was presented. It was concluded that simulation results demonstrated that decreasing scN not only increased pore pressure above hydrostatic values, but also lowered the lithostatic stress gradient and gas hydrate saturation. This occurred because overpressure resulted in lower effective stress, causing higher porosity and lower bulk density of the sediment. 16 refs., 5 figs., 1 appendix.

Leak detection for city gas pipelines based on instantaneous energy distribution characteristics

Energy Technology Data Exchange (ETDEWEB)

Zhigang, Chen [Deijing University of Civil Engineering and Architecture, Beijing, (China)

2010-07-01

Many natural gas pipelines are used in our cities. The development of efficient leakage detection systems is fundamental for safety issues avoidance. This paper investigated a new solution to the leak detection problem in city gas pipelines based on instantaneous energy distribution. In a theoretical approach, the Hilbert-Huang transform (HHT) was used to provide the instantaneous energy distribution feature of an unstable pressure signal. The signal noise was eliminated thanks to the instantaneous energy contribution. A leakage detection model with instantaneous energy distribution (IED) was then established. The correlation coefficients of instantaneous energy distribution were through correlation analysis. It was found that in different pipeline states, the instantaneous energy distribution characteristics are different. A strong correlation of IED signal characteristics was found of the two ends of a city gas pipeline in the same operation. The test results demonstrated the reliability and validity of the method.

FINANCING OF INVESTMENT PROJECTS OF GAS DISTRIBUTION ENTERPISES AS A FACTOR OF THEIR DEVELOPMENT

Directory of Open Access Journals (Sweden)

Svitlana Korol

2016-03-01

Full Text Available In the article theoretical questions of formation sources of financing investments   are  considered, the analysis of investment activities is carried out by the sources of funding for gas  utility. The purpose of this article is to identify priority sources of financing investment activities of gas distribution enterprises. The  methodology  of  research.  To  achieve  this  goal  the  author  used  methods  of  theoretical generalization; statistical and financial methods in the study of dynamics and structure of  investment; tabular methods to display the structure of the main sources of financing of  the  investment program of gas distribution enterprises; consistency and comparison, to determine the relationship between the main components of investment sources of financing. As a result of research by critical retrospective analysis to determine the structure of sources of financing investment activities of gas distribution enterprises. It is established that the main sources of financing the investment program are the tariffs for transportation and supply of gas, says the national Commission, carrying out state regulation in the areas of energy and  utilities (NCREU. It is filed the structure of the main financing sources of the investment  program of gas distribution enterprises. It is proved that the level of funding depends on the size  of NCREU rates and gas consumption. Scientific novelty of the article is lack in domestic and foreign areas of research priority  selection of sources financing of the investment program for gas distribution enterprises. The practical significance is that the theoretical concepts, practical results and conclusions of  articles that reveal the essence of the problem of investment sources of financing, can be used in  the activity of gas distribution enterprises taking into account the current state of development  of the economy. Keywords: investment  resources,  financing

Research on Distributed Gas Detection Based on Hollow-core Photonic Crystal Fiber

Directory of Open Access Journals (Sweden)

Gui XIN

2014-07-01

Full Text Available We have demonstrated a distributed gas detection system by using hollow-core photonic crystal fiber (HC-PCF as a gas chamber. The HC-PCF gas chamber has several lateral micro- channels fabricated by the femtosecond laser. The HC-PCF is connected to the single mode fiber by thermal splicing, and gas can diffuse in hollow-core of PCF via micro-channels. Compared to the traditional gas chamber, the HC-PCF gas chamber has relatively simpler construction and quite stability. According to experiment results, the system response time of 15 s has been achieved for a 5 cm HC-PCF which has ten channels with 4mm channel distance. It would construct long sensing length fiber gas sensor that the side holes and the splicer have introduced very little loss. Thus make it possible to achieve highly sensitive sensing system without influencing the response time. By using self-reference demodulation algorithm and space division multiplexing technique, distributed gas detection system with fast response was achieved.

75 FR 5244 - Pipeline Safety: Integrity Management Program for Gas Distribution Pipelines; Correction

Science.gov (United States)

2010-02-02

... Management Program for Gas Distribution Pipelines; Correction AGENCY: Pipeline and Hazardous Materials Safety... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration 49 CFR Part... Regulations to require operators of gas distribution pipelines to develop and implement integrity management...

Japan does it mainly compact and flexible: Innovate improvements in the natural gas distribution technique and gas appliances

International Nuclear Information System (INIS)

Roebers, H.

1994-01-01

Specific Japanese innovative improvements in natural gas distribution systems and natural gas appliances are outlined, based on the KAI-ZEN philosophy. Attention is paid to the design of flexible gas pipes, gas plug-in sockets, and safety systems, and the compact design of gas appliances. Much of the innovations focus on details. Briefly, the NEXT 21 project is described, which project anticipates the silent wishes of the Japanese people with regard to lifestyle

SIZE REDUCTION OF ELECTROSTATIC PRECIPITATOR CHAMBER BY MODIFICATION OF GAS FLOW DISTRIBUTION

Directory of Open Access Journals (Sweden)

Beata Sładkowska-Rybka

2014-10-01

Full Text Available Electrostatic precipitators (ESP are one of the most effective devices for particulate emission control, removing from the exhaust gases even 99,9 % of dust particles. The collection efficiency of the ESP depends on a number of factors: mechanical design and electrical operating parameters, physical and chemical properties of cleaned gas, characteristic of dust particles suspended in the gas. Among the most important factors affecting the ESP effectiveness, the velocity and the distribution of gas flow in the ESP chamber should be also indicated. Significant increase in ESP efficiency is possible thanks to the application of Skewed Gas Flow Technology (SGFT. In this paper the computer simulations results are shown. Authors investigated the possibility of ESP chamber size reduction by modification of gas flow distribution.

General Analysis of System Efficiency in Application of Combined Power Plants for Gas-Distribution Station

Directory of Open Access Journals (Sweden)

A. D. Kachan

2004-01-01

Full Text Available The paper proposes utilization of discharged heat of gas-piston engine (GPE or contact steam-gas plants (SGP with the purpose to heat up gas at gas-distribution stations (GDS of combined power plants with turbine and gas-expansion units. Calculations prove significant economic efficiency of the proposed variant in comparison with the application of ordinary gas- turbine units. Technical and economic calculation is used to determine gas-piston engine or contact steam-gas plant power for specific operational conditions of gas-distribution stations and utilization rate of discharged heat.

Having our gas and selling it too : natural gas distribution in Atlantic Canada

International Nuclear Information System (INIS)

Tucker, T.L.; Crowley, B.L.

2002-01-01

This paper presented an overview of the gas industry in Atlantic Canada, its history and development, with particular attention to the future of natural gas in Atlantic Canada, market pricing and rationalized regulation. It also includes a primer on the economic forces behind the industry. A regulatory framework was recommended that will provide gas to the greatest number of consumers at the lowest possible price. The report also describes 10 popular misconceptions regarding how the region believes it can best benefit from natural gas. The report dispels the idea that the greatest benefit comes from consuming natural gas locally. Other misconceptions are that gas can be sold locally at discount prices and at a premium to export markets. It was emphasized that Atlantic Canada needs the gas as much as New England markets, but the investment by consumers in the United States are a big driving force for offshore gas development. The author emphasized that even if Atlantic Canada never consumes its own natural gas, the royalties, economic growth, economic diversification and a new addition to the energy mix will generate benefits much greater than those which could come from local consumption alone. The author also suggests that the lack of market power in Atlantic Canada means that gas-specific provincial regulations to protect the public interest are not required. It was suggested that a gas distributor should be chosen to build the infrastructure and attract customers. This paper demonstrated that the greatest benefit to the region will come from deregulating the distribution industry while realizing the full market value of the gas for its owners. 15 refs

Estimation of potential distribution of gas hydrate in the northern South China Sea

Science.gov (United States)

Wang, Chunjuan; Du, Dewen; Zhu, Zhiwei; Liu, Yonggang; Yan, Shijuan; Yang, Gang

2010-05-01

Gas hydrate research has significant importance for securing world energy resources, and has the potential to produce considerable economic benefits. Previous studies have shown that the South China Sea is an area that harbors gas hydrates. However, there is a lack of systematic investigations and understanding on the distribution of gas hydrate throughout the region. In this paper, we applied mineral resource quantitative assessment techniques to forecast and estimate the potential distribution of gas hydrate resources in the northern South China Sea. However, current hydrate samples from the South China Sea are too few to produce models of occurrences. Thus, according to similarity and contrast principles of mineral outputs, we can use a similar hydrate-mining environment with sufficient gas hydrate data as a testing ground for modeling northern South China Sea gas hydrate conditions. We selected the Gulf of Mexico, which has extensively studied gas hydrates, to develop predictive models of gas hydrate distributions, and to test errors in the model. Then, we compared the existing northern South China Sea hydrate-mining data with the Gulf of Mexico characteristics, and collated the relevant data into the model. Subsequently, we applied the model to the northern South China Sea to obtain the potential gas hydrate distribution of the area, and to identify significant exploration targets. Finally, we evaluated the reliability of the predicted results. The south seabed area of Taiwan Bank is recommended as a priority exploration target. The Zhujiang Mouth, Southeast Hainan, and Southwest Taiwan Basins, including the South Bijia Basin, also are recommended as exploration target areas. In addition, the method in this paper can provide a useful predictive approach for gas hydrate resource assessment, which gives a scientific basis for construction and implementation of long-term planning for gas hydrate exploration and general exploitation of the seabed of China.

Adding Live-Streaming to Recorded Lectures in a Non-Distributed Pre-Clerkship Medical Education Model.

Science.gov (United States)

Sandhu, Amanjot; Fliker, Aviva; Leitao, Darren; Jones, Jodi; Gooi, Adrian

2017-01-01

Live-streaming video has had increasing uses in medical education, especially in distributed education models. The literature on the impact of live-streaming in non-distributed education models, however, is scarce. To determine the attitudes towards live-streaming and recorded lectures as a resource to pre-clerkship medical students in a non-distributed medical education model. First and second year medical students were sent a voluntary cross-sectional survey by email, and were asked questions on live-streaming, recorded lectures and in person lectures using a 5-point Likert and open answers. Of the 118 responses (54% response rate), the data suggested that both watching recorded lectures (Likert 4.55) and live-streaming lectures (4.09) were perceived to be more educationally valuable than face-to-face attendance of lectures (3.60). While responses indicated a statistically significant increase in anticipated classroom attendance if both live-streaming and recorded lectures were removed (from 63% attendance to 76%, p =0.002), there was no significant difference in attendance if live-streaming lectures were removed but recorded lectures were maintained (from 63% to 66%, p=0.76). The addition of live-streaming lectures in the pre-clerkship setting was perceived to be value added to the students. The data also suggests that the removal of live-streaming lectures would not lead to a statistically significant increase in classroom attendance by pre-clerkship students.

Forms of contractual documents for public gas distribution; Modeles de documents contractuels pour la distribution publique de gaz

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-12-01

This document is a compilation of standard forms of concession agreements and of specifications for public gas distribution (general dispositions, granted network and works, connection to the granted network, gas quality, contracts and conditions of supply, gas prices, concession end and control, various dispositions, agreement between the town and the grantee, calculation of profit rate, gas retail prices, general conditions of supply). (J.S.)

Effect of pH on molecular constitution and distribution of hemoglobin in living erythrocyte.

Science.gov (United States)

Wu, Yue; Huang, Yao-Xiong; Kang, Li-Li; Wu, Zheng-Jie; Luo, Man

2010-04-01

The molecular constitution of in situ hemoglobin (Hb) and their distribution in living erythrocyte were investigated versus pH using the technique of confocal Raman microscopy. Both Raman point spectra and line mapping measurements were performed on living erythrocytes in suspensions with pH values from 4.82 to 9.70. It was found that the Hb inside a living erythrocyte would dissociate into monomer/dimer when the cells are in low and high pH environments. In contrast to the homogeneous distribution of the Hbs in the cells in neutral suspension, there are more Hbs distributing around the cell membrane or binding to the membrane as pH increases. While in low pH, as the cell become spherical, most of the Hbs distribute to the central part of the cell. In summary, our investigation suggests that the variation of the external pH not only brings changes in the morphology and membrane structure of an erythrocyte, but also affects the constitution and distribution of its intracellular Hbs, thereby the flexibility of the cell membrane and the oxygenation ability of the Hb.

Productivity and quality improvements. A report on cost management in gas distribution at the energy distribution company Amsterdam (Energie Noord West Amsterdam NV)

International Nuclear Information System (INIS)

Bosch, T.

1997-01-01

In a more competitive times traditional and technical industries like gas distribution have to change. They have to commercialize. A way to support this transition is to introduce an activity based cost control system (ABC) with proper delegation of financial responsibilities. This report is about the history of cost management in Amsterdam and the introduction of ABC in our distribution company. The message to other gas distributors is that introducing some form of ABC can be worth wile in the future and is probably inescapable because of growing competition. In the end gas distribution will probably turn out to be one of the few places where money can be earned in the entire gas trade. Not by increasing distribution prices, but by decreasing distribution costs and strategic investments. (au)

Minimization of Blast furnace Fuel Rate by Optimizing Burden and Gas Distribution

Energy Technology Data Exchange (ETDEWEB)

Dr. Chenn Zhou

2012-08-15

The goal of the research is to improve the competitive edge of steel mills by using the advanced CFD technology to optimize the gas and burden distributions inside a blast furnace for achieving the best gas utilization. A state-of-the-art 3-D CFD model has been developed for simulating the gas distribution inside a blast furnace at given burden conditions, burden distribution and blast parameters. The comprehensive 3-D CFD model has been validated by plant measurement data from an actual blast furnace. Validation of the sub-models is also achieved. The user friendly software package named Blast Furnace Shaft Simulator (BFSS) has been developed to simulate the blast furnace shaft process. The research has significant benefits to the steel industry with high productivity, low energy consumption, and improved environment.

Power-law distributions for a trapped ion interacting with a classical buffer gas.

Science.gov (United States)

DeVoe, Ralph G

2009-02-13

Classical collisions with an ideal gas generate non-Maxwellian distribution functions for a single ion in a radio frequency ion trap. The distributions have power-law tails whose exponent depends on the ratio of buffer gas to ion mass. This provides a statistical explanation for the previously observed transition from cooling to heating. Monte Carlo results approximate a Tsallis distribution over a wide range of parameters and have ab initio agreement with experiment.

Challenge and opportunity: developing a gas distribution industry in New Brunswick

Energy Technology Data Exchange (ETDEWEB)

Pleckaitis, A.J. [Enbridge Gas New Brunswick, Fredericton, NB (Canada)

2001-07-01

The largest gas distributor in Canada is Enbridge, which also operates the longest oil pipeline system in the world. In this presentation, the author discussed the challenges facing Enbridge Gas New Brunswick (EGNB). The limited partnership, the 20-year renewable franchise and the business plan was briefly examined. The state of development of EGNB was described with the back-bone distribution system having been completed and the first customers attached. EGNB is in the process of developing the supporting infrastructure. A map of the Eastern region of the country was shown, followed by a map of New Brunswick displaying the work accomplished to date. A brief overview of the business model was provided and the challenges identified. The customer value chain was illustrated, and a graph showed the natural gas price advantage in New Brunswick. Next, the author discussed the situation in Nova Scotia, where the gas distribution franchise was awarded in December 1999 to Sempra Atlantic Gas. Looking to the future, the author mentioned supply and regional strategy. The final thought was for greater cooperation between government and industry. figs.

The impact of small scale cogeneration on the gas demand at distribution level

International Nuclear Information System (INIS)

Vandewalle, J.; D’haeseleer, W.

2014-01-01

Highlights: • Impact on the gas network of a massive implementation of cogeneration. • Distributed energy resources in a smart grid environment. • Optimisation of cogeneration scheduling. - Abstract: Smart grids are often regarded as an important step towards the future energy system. Combined heat and power (CHP) or cogeneration has several advantages in the context of the smart grid, which include the efficient use of primary energy and the reduction of electrical losses through transmission. However, the role of the gas network is often overlooked in this context. Therefore, this work presents an analysis of the impact of a massive implementation of small scale (micro) cogeneration units on the gas demand at distribution level. This work shows that using generic information in the simulations overestimates the impact of CHP. Furthermore, the importance of the thermal storage tank capacity on the impact on the gas demand is shown. Larger storage tanks lead to lower gas demand peaks and hence a lower impact on the gas distribution network. It is also shown that the use of an economically led controller leads to similar results compared to classical heat led control. Finally, it results that a low sell back tariff for electricity increases the impact of cogeneration on the gas demand peak

Dynamic analysis of natural gas distribution sector in Bahia: case study of the Gas State Company entry

International Nuclear Information System (INIS)

Ribeiro, H.M.

1988-01-01

For the Natural Gas Distribution Sector in Bahia, some preliminary scenarios and theoretical concerns are presented under the perspectives of the Gas State Company entry. These scenarios are derived from the going institutional changes and physical expansion of the Sector with the increasing natural gas usage. The study has the objective of anticipating, for the State Government and its partners in the Company, the strategies and relevant problems for a successful entrance into this Sector. (author)

Hybrid ATDL-gamma distribution model for predicting area source acid gas concentrations

Energy Technology Data Exchange (ETDEWEB)

Jakeman, A J; Taylor, J A

1985-01-01

An air quality model is developed to predict the distribution of concentrations of acid gas in an urban airshed. The model is hybrid in character, combining reliable features of a deterministic ATDL-based model with statistical distributional approaches. The gamma distribution was identified from a range of distributional models as the best model. The paper shows that the assumptions of a previous hybrid model may be relaxed and presents a methodology for characterizing the uncertainty associated with model predictions. Results are demonstrated for the 98-percentile predictions of 24-h average data over annual periods at six monitoring sites. This percentile relates to the World Health Organization goal for acid gas concentrations.

The gas bubbles distribution in 600 MeV protons irradiated aluminium

International Nuclear Information System (INIS)

Gavillet, D.; Martin, J.L.; Victoria, M.; Green, W.

1984-01-01

In order to simulate the damage produced by 14 MeV fusion neutrons, thin foils of high purity Al have been irradiated by a proton beam of 580 MeV (120μA). After irradiation at temperatures higher than 0.5 Tm transmission electron microscope observations of gas bubbles distribution were performed. At 200 0 C a uniform distribution of bubbles has been observed inside the grain. The average distance between bubbles and their density have been determined. The gas pressure inside the bubbles has been estimated [fr

Ventilation distribution in rats: Part I - The effect of gas composition as measured with electrical impedance tomography

Directory of Open Access Journals (Sweden)

Dunster Kimble R

2012-09-01

Full Text Available Abstract The measurement of ventilation distribution is currently performed using inhaled tracer gases for multiple breath inhalation studies or imaging techniques to quantify spatial gas distribution. Most tracer gases used for these studies have properties different from that of air. The effect of gas density on regional ventilation distribution has not been studied. This study aimed to measure the effect of gas density on regional ventilation distribution. Methods Ventilation distribution was measured in seven rats using electrical impedance tomography (EIT in supine, prone, left and right lateral positions while being mechanically ventilated with either air, heliox (30% oxygen, 70% helium or sulfur hexafluoride (20% SF6, 20% oxygen, 60% air. The effect of gas density on regional ventilation distribution was assessed. Results Gas density did not impact on regional ventilation distribution. The non-dependent lung was better ventilated in all four body positions. Gas density had no further impact on regional filling characteristics. The filling characteristics followed an anatomical pattern with the anterior and left lung showing a greater impedance change during the initial phase of the inspiration. Conclusion It was shown that gas density did not impact on convection dependent ventilation distribution in rats measured with EIT.

Deviations from the Boltzmann distribution in vibrationally excited gas flows

International Nuclear Information System (INIS)

Offenhaeuser, F.; Frohn, A.

1986-01-01

A new model for the exchange of vibrational energy in one-dimensional flows of CO 2 -H 2 O-N 2 -O 2 -He gas mixtures is presented. In contrast to previous models, the assumption of local Boltzmann distributions for the vibrational degrees of freedom is not required. This generalization was achieved by the assumption that the molecules are harmonic oscillators with one or more degrees of freedom represented by finite numbers of energy levels. The population densities of these energy levels are coupled by a set of rate equations. It is shown that in some cases of molecular gas flow the Boltzmann distribution for the vibrational degrees of freedom may be disturbed. 12 references

A global survey of the distribution of free gas in marine sediments

Science.gov (United States)

Fleischer, Peter; Orsi, Tim; Richardson, Michael

2003-10-01

Following the work of Aubrey Anderson in the Gulf of Mexico, we have attempted to quantify the global distribution of free gas in shallow marine sediments, and have identified and indexed over one hundred documented cases in the scientific and engineering literature. Our survey confirms previous assumptions, primarily that gas bubbles are ubiquitous in the organic-rich muds of coastal waters and shallow adjacent seas. Acoustic turbidity as recorded during seismo-acoustic surveys is the most frequently cited evidence used to infer the presence of seafloor gas. Biogenic methane predominates within these shallow subbottom deposits. The survey also reveals significant imbalances in the geographic distribution of studies, which might be addressed in the future by accessing proprietary data or local studies with limited distribution. Because of their global prevalence, growing interest in gassy marine sediments is understandable as their presence has profound scientific, engineering and environmental implications.

PVC pipes in gas distribution: still going strong!

NARCIS (Netherlands)

Hermkens, Rene; Wolters, Mannes; Weller, Jeroen; Visser, Roy; Davidovski, Z.; Belloir, P.; Fumire, J.

2008-01-01

In the Netherlands (impact-modified) PVC is the preferred material for low-pressure (30 and 100 mbar) gas distribution systems. More than 50% of the total length (about 122,000 km) of this system is rigid PVC or impact-modified PVC. The installation of rigid PVC (uPVC) pipelines started about 50

A theoretical cost optimization model of reused flowback distribution network of regional shale gas development

International Nuclear Information System (INIS)

Li, Huajiao; An, Haizhong; Fang, Wei; Jiang, Meng

2017-01-01

The logistical issues surrounding the timing and transport of flowback generated by each shale gas well to the next is a big challenge. Due to more and more flowback being stored temporarily near the shale gas well and reused in the shale gas development, both transportation cost and storage cost are the heavy burden for the developers. This research proposed a theoretical cost optimization model to get the optimal flowback distribution solution for regional multi shale gas wells in a holistic perspective. Then, we used some empirical data of Marcellus Shale to do the empirical study. In addition, we compared the optimal flowback distribution solution by considering both the transportation cost and storage cost with the flowback distribution solution which only minimized the transportation cost or only minimized the storage cost. - Highlights: • A theoretical cost optimization model to get optimal flowback distribution solution. • An empirical study using the shale gas data in Bradford County of Marcellus Shale. • Visualization of optimal flowback distribution solutions under different scenarios. • Transportation cost is a more important factor for reducing the cost. • Help the developers to cut the storage and transportation cost of reusing flowback.

Probing the regional distribution of pulmonary gas exchange through single-breath gas- and dissolved-phase 129Xe MR imaging.

Science.gov (United States)

Kaushik, S Sivaram; Freeman, Matthew S; Cleveland, Zackary I; Davies, John; Stiles, Jane; Virgincar, Rohan S; Robertson, Scott H; He, Mu; Kelly, Kevin T; Foster, W Michael; McAdams, H Page; Driehuys, Bastiaan

2013-09-01

Although some central aspects of pulmonary function (ventilation and perfusion) are known to be heterogeneous, the distribution of diffusive gas exchange remains poorly characterized. A solution is offered by hyperpolarized 129Xe magnetic resonance (MR) imaging, because this gas can be separately detected in the lung's air spaces and dissolved in its tissues. Early dissolved-phase 129Xe images exhibited intensity gradients that favored the dependent lung. To quantitatively corroborate this finding, we developed an interleaved, three-dimensional radial sequence to image the gaseous and dissolved 129Xe distributions in the same breath. These images were normalized and divided to calculate "129Xe gas-transfer" maps. We hypothesized that, for healthy volunteers, 129Xe gas-transfer maps would retain the previously observed posture-dependent gradients. This was tested in nine subjects: when the subjects were supine, 129Xe gas transfer exhibited a posterior-anterior gradient of -2.00 ± 0.74%/cm; when the subjects were prone, the gradient reversed to 1.94 ± 1.14%/cm (P exchange caused by differences in lung inflation and posture.

Further comprehension of natural gas accumulation, distribution, and prediction prospects in China

Directory of Open Access Journals (Sweden)

Jun Li

2017-06-01

Full Text Available In-depth research reveals that the natural gas accumulation and distribution are characterized by cycle, sequence, equilibrium, traceability, and multi-stage. To be specific, every geotectonic cycle represents a gas reservoir forming system where natural gas is generated, migrated, accumulated, and formed into a reservoir in a certain play. Essentially, hydrocarbon accumulation occurs when migration force and resistance reach an equilibrium. In this situation, the closer to the source rock, the higher the accumulation efficiency is. Historically, reservoirs were formed in multiple phases. Moreover, zones in source rocks and adjacent to source rocks, unconformity belts, and faulted anticline belts are favorable areas to finding large gas fields. Apart from the common unconformity belts and faulted anticline belts, in-source and near-source zones should be considered as critical targets for future exploration. Subsequent exploration should focus on Upper Palaeozoic in the southeastern Ordos Basin, Triassic in southwestern Sichuan Basin, Jurassic in the northern section of the Kuqa Depression and other zones where no great breakthroughs have been made. Keywords: Large gas field, Distribution characteristics, Potential zone, Prospect

CRE proposal for the tariffs of use of natural gas distribution networks

International Nuclear Information System (INIS)

Syrota, J.

2003-12-01

Each French manager of a natural gas distribution network has its own tariff of network use. This document defines the general tariffing rules applicable to all natural gas distribution networks (options, penalties in case of overstepping of the subscribed daily capacity, special option for the supply of the 'Gaz de Barr' network, services included in the tariff). The detailed tariffs of use are given for each gas utility (Gaz de France, Gaz de Bordeaux, Gaz de Strasbourg, Regie Municipale de Colmar (Vialis), Gaz Electricite de Grenoble, Regie Municipale de Dreux (GEdia), Gaz de Barr, Service Gaz et Eau de la Ville de Guebwiller, Syndicat Intercommunal de Huningue, St Louis, Hegenheim et Village Neuf, Regie d'Equipement et Gaz de la Vienne etc..). (J.S.)

Current distribution measurements inside an electromagnetic plasma gun operated in a gas-puff mode

OpenAIRE

Poehlmann, Flavio R.; Cappelli, Mark A.; Rieker, Gregory B.

2010-01-01

Measurements are presented of the time-dependent current distribution inside a coaxial electromagnetic plasma gun. The measurements are carried out using an array of six axially distributed dual-Rogowski coils in a balanced circuit configuration. The radial current distributions indicate that operation in the gas-puff mode, i.e., the mode in which the electrode voltage is applied before injection of the gas, results in a stationary ionization front consistent with the presence of a plasma def...

Model documentation: Natural gas transmission and distribution model of the National Energy Modeling System. Volume 1

International Nuclear Information System (INIS)

1995-01-01

The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A

Model documentation: Natural gas transmission and distribution model of the National Energy Modeling System. Volume 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-02-17

The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of integrated Analysis and Forecasting of the Energy information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The methodology employed allows the analysis of impacts of regional capacity constraints in the interstate natural gas pipeline network and the identification of pipeline capacity expansion requirements. There is an explicit representation of core and noncore markets for natural gas transmission and distribution services, and the key components of pipeline tariffs are represented in a pricing algorithm. Natural gas pricing and flow patterns are derived by obtaining a market equilibrium across the three main elements of the natural gas market: the supply element, the demand element, and the transmission and distribution network that links them. The NGTDM consists of four modules: the Annual Flow Module, the Capacity F-expansion Module, the Pipeline Tariff Module, and the Distributor Tariff Module. A model abstract is provided in Appendix A.

Pricing natural gas distribution in Mexico

International Nuclear Information System (INIS)

Ramirez, Jose Carlos; Rosellon, Juan

2002-01-01

We examine regulation of distribution tariffs in the Mexican natural gas industry. Average revenue in each period is constrained not to exceed an upper bound and is calculated as the ratio of total revenue to output in the current period. This regime implies incentives for strategically setting two-part tariffs. The usage charge is typically dropped to its lowest feasible level, while the fixed charge is raised to compensate for the loss of profit. The regime also creates a stochastic effect that implies decreased values of consumer surplus for lower levels of risk aversion and uncertainty

New ultrasonographic evaluation of stool and/or gas distribution for treatment of chronic constipation.

Science.gov (United States)

Manabe, Noriaki; Kamada, Tomoari; Hata, Jiro; Haruma, Ken

2018-03-01

The first aim of this study was to develop a new ultrasonographic method (US) to evaluate stool and/or gas distribution. The second aim was to apply this method to compare stool and/or gas distribution between healthy subjects and patients with chronic constipation and evaluate whether US parameters could be an alternative to the colonic transit time (CTT). We enrolled seven healthy volunteers (four men, three women; mean age 29.3 ± 5.2 years) who underwent US and computed tomography (CT) on the same day to evaluate the reproducibility of US results. We then enrolled 268 patients with chronic constipation (94 men, 174 women; mean age 63.3 ± 4.2 years) and 66 age- and sex-matched healthy subjects (controls). The transverse diameters of four segments of the colon [ascending (AC), transverse (TC), descending (DC), and sigmoid (SC)] and the rectum (R) were measured, and their stool and/or gas distribution was evaluated using the constipation index (CI) [AC + TC + DC + SC + R/5] and left/right (L/R) distribution [(DC + SC)/(AC + TC)]. The CTT was assessed using radiopaque markers. All healthy subjects underwent US and CT successfully, with a sufficiently high reproducibility coefficient for this method and significant correlation between the US and CT parameters. The stool and/or gas distribution evaluated by US showed a significant difference in one of the US parameters between healthy subjects and patients, and the CI was an indirect indicator for the CTT. These findings may assist physicians evaluate stool and/or gas distribution of patients with chronic constipation, which is an indirect indicator for CTT.

Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-01-01

The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. The NGTDM is the model within the NEMS that represents the transmission, distribution, and pricing of natural gas. The model also includes representations of the end-use demand for natural gas, the production of domestic natural gas, and the availability of natural gas traded on the international market based on information received from other NEMS models. The NGTDM determines the flow of natural gas in an aggregate, domestic pipeline network, connecting domestic and foreign supply regions with 12 demand regions. The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. Subsequent chapters of this report provide: an overview of NGTDM; a description of the interface between the NEMS and NGTDM; an overview of the solution methodology of the NGTDM; the solution methodology for the Annual Flow Module; the solution methodology for the Distributor Tariff Module; the solution methodology for the Capacity Expansion Module; the solution methodology for the Pipeline Tariff Module; and a description of model assumptions, inputs, and outputs.

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.

Real gas flow simulation in damaged distribution pipelines

International Nuclear Information System (INIS)

Kostowski, Wojciech J.; Skorek, Janusz

2012-01-01

The paper discusses chosen issues concerning damaged gas pipelines. Attention is paid to modelling the steady-state flow of natural gas in distribution pipelines, and the most commonly applied models of isothermal and adiabatic flow are evaluated for both the ideal and the real gas properties. A method of accounting for a leakage by means of a reference flow equation with a discharge coefficient is presented, and the dependency of the discharge coefficient on pressure is demonstrated both with literature data and the authors' experimental results. A relevant computational study of a pipeline failure is presented for a high- and a medium pressure pipeline. The importance of an appropriate choice of the flow model (isothermal or adiabatic flow of real or ideal gas) is demonstrated by the results of the study. It is shown that accounting for the variability of the discharge coefficient is required if medium pressure pipelines are analysed. However, it is eventually shown that the impact of the discharge coefficient on the predicted outflow rate is of lesser importance than that of the applied flow model. -- Highlights: ► Comparison of real/ideal gas, isothermal/adiabatic gas flow in a damaged pipeline. ► Variability of the discharge coefficient with pressure is demonstrated. ► Isothermal model predicts wrong values of downstream pressure, not just temperature. ► Isothermal model may cause significant error (for 2 case studies is >20%). ► Error in the discharge coefficient has a weak influence on the predicted flow rate.

Determination of gas temperature in the plasmatron channel according to the known distribution of electronic temperature

Directory of Open Access Journals (Sweden)

Gerasimov Alexander V.

2013-01-01

Full Text Available An analytical method to calculate the temperature distribution of heavy particles in the channel of the plasma torch on the known distribution of the electronic temperature has been proposed. The results can be useful for a number of model calculations in determining the most effective conditions of gas blowing through the plasma torch with the purpose of heating the heavy component. This approach allows us to understand full details about the heating of cold gas, inpouring the plasma, and to estimate correctly the distribution of the gas temperature inside the channel.

Distribution, vertical position and ecological implications of shallow gas in Bahía Blanca estuary (Argentina)

Science.gov (United States)

Bravo, M. E.; Aliotta, S.; Fiori, S.; Ginsberg, S.

2018-03-01

There has been a growing interest in the study of shallow gas due its importance in relation to the marine environment, climate change and human activities. In Bahía Blanca estuary, Argentina, shallow gas has a wide distribution. Acoustic turbidity and blanking are the main seismic evidence for the presence of shallow gas in the estuary. The former prevails in the inner sector of the estuary where gas is either near or in contact with the seabed. Gas deposits are generally associated with paleochannels corresponding to the Holocene paleodeltaic environment. Distribution studies of shallow gas in this estuary are necessary because its presence implies not only a geological risk for harbor activities but also because it may have noxious effects on the marine ecosystem, mainly on benthic communities. The comparison of benthic communities at a gas site (GS) with those at a control site (CS) indicated that gas could generate impoverishment in terms of individuals' abundance (GS: N = 357; CS: N = 724). Also, diversity indices showed great differences in the community structure at each site. This indicates that methane gas may act as a natural disturbance agent in estuarine ecosystems. The presence of gas in seabed sediments must therefore be taken into account when distribution studies are conducted of estuarine benthic communities.

Fractal analysis of the dark matter and gas distributions in the Mare-Nostrum universe

International Nuclear Information System (INIS)

Gaite, José

2010-01-01

We develop a method of multifractal analysis of N-body cosmological simulations that improves on the customary counts-in-cells method by taking special care of the effects of discreteness and large scale homogeneity. The analysis of the Mare-Nostrum simulation with our method provides strong evidence of self-similar multifractal distributions of dark matter and gas, with a halo mass function that is of Press-Schechter type but has a power-law exponent -2, as corresponds to a multifractal. Furthermore, our analysis shows that the dark matter and gas distributions are indistinguishable as multifractals. To determine if there is any gas biasing, we calculate the cross-correlation coefficient, with negative but inconclusive results. Hence, we develop an effective Bayesian analysis connected with information theory, which clearly demonstrates that the gas is biased in a long range of scales, up to the scale of homogeneity. However, entropic measures related to the Bayesian analysis show that this gas bias is small (in a precise sense) and is such that the fractal singularities of both distributions coincide and are identical. We conclude that this common multifractal cosmic web structure is determined by the dynamics and is independent of the initial conditions

Regulation of the natural gas distribution sector: a comparison of Brazilian and Colombian industries; Regulacao do setor de distribuicao de gas natural: uma comparacao dos casos brasileiro e colombiano

Energy Technology Data Exchange (ETDEWEB)

Domingues, Mariana Peralva; Ferraro, Marcelo Colomer [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)

2008-07-01

The Bolivia oil industry nationalization in 2006 and the high price of oil on the international market called the public and government attention to the problems of the natural gas industry regulation in Brazil. Recently, the establishment of a specific law for the natural gas industry had been debated in academic circles and in government institutions. In Brazil, the absence of an integrated energy policy and the absence of a homogeneous regulatory framework interfere with natural gas industry development, especially in distribution. Thus, the objective of the work will be contrast the Colombia distribution natural gas regulatory structure sector to the Brazilian natural gas regulatory framework. The comparison of the Brazilian regulatory framework and the Colombian natural gas regulation shows that the existence of different kinds of concession contracts in distribution is one of the explanations for the different levels of investment in Brazil. The contract with exclusive right to explore the distribution service in geographic territories also contributes to explain the low coverage rate of public distribution companies. Thus, the rapid expansion of the natural gas distribution network in Colombia after the regulatory reforms shows the importance of the establishment of a regulatory structure to push private investment. The Colombian case can be considered a good model for other countries in South America, especially to the natural gas distribution regulation. (author)

Analysis of Neutron Flux Distribution in Rsg-Gas Reactor With U-Mo Fuels

Directory of Open Access Journals (Sweden)

Taswanda Taryo

2004-01-01

Full Text Available The use of U-Mo fuels in research reactors seems to be promising and, recently, world researchers have carried out these such activities actively. The National Nuclear Energy Agency (BATAN which owns RSG-GAS reactor available in Serpong Research Center for Atomic Energy should anticipate this trend. It is, therefore, this research work on the use of U-Mo fuels in RSG-GAS reactor should be carried out. The work was focused on the analysis of neutron flux distribution in the RSG-GAS reactor using different content of molybdenum in U-Mo fuels. To begin with, RSG-GAS reactor core model was developed and simulated into X, Y and Z dimensions. Cross section of materials based on the developed cells of standard and control fuels was then generated using WIMS-D5-B. The criticality calculations were finally carried out applying BATAN-2DIFF code. The results showed that the neutron flux distribution obtained in U-Mo-fuel-based RSG-GAS core is very similar to those achieved in the 300-gram sillicide-fuel-based RSG-GAS reactor core. Indeed, the utilization of the U-Mo RSG-GAS core can be very similar to that of the high-density sillicide reactor core and even could be better in the future.

The constitutive distributed parameter model of multicomponent chemical processes in gas, fluid and solid phase

International Nuclear Information System (INIS)

Niemiec, W.

1985-01-01

In the literature of distributed parameter modelling of real processes is not considered the class of multicomponent chemical processes in gas, fluid and solid phase. The aim of paper is constitutive distributed parameter physicochemical model, constructed on kinetics and phenomenal analysis of multicomponent chemical processes in gas, fluid and solid phase. The mass, energy and momentum aspects of these multicomponent chemical reactions and adequate phenomena are utilized in balance operations, by conditions of: constitutive invariance for continuous media with space and time memories, reciprocity principle for isotropic and anisotropic nonhomogeneous media with space and time memories, application of definitions of following derivative and equation of continuity, to the construction of systems of partial differential constitutive state equations, in the following derivative forms for gas, fluid and solid phase. Couched in this way all physicochemical conditions of multicomponent chemical processes in gas, fluid and solid phase are new form of constitutive distributed parameter model for automatics and its systems of equations are new form of systems of partial differential constitutive state equations in sense of phenomenal distributed parameter control

Distribution and characteristics of gamma and cosmic ray dose rate in living environment

International Nuclear Information System (INIS)

Nagaoka, Toshi; Moriuchi, Shigeru

1991-01-01

A series of environmental radiation surveys was carried out from the viewpoint of characterizing the natural radiation dose rate distribution in the living environment, including natural and artificial ones. Through the analysis of the data obtained at numbers of places, several aspects of the radiation field in living environments were clarified. That is the gamma ray dose rate varies due to the following three dominant causes: 1) the radionuclide concentration of surrounding materials acting as gamma ray sources, 2) the spatial distribution of surrounding materials, and 3) the geometrical and shielding conditions between the natural gamma ray sources and the measured point; whereas, the cosmic ray dose rate varies due to the thickness of upper shielding materials. It was also suggested that the gamma ray dose rate generally shows an upward tendency, and the cosmic ray dose rate a downward one in artificial environment. This kind of knowledge is expected to serve as fundamental information for accurate and realistic evaluation of the collective dose in the living environment. (author)

Statistical distribution for generalized ideal gas of fractional-statistics particles

International Nuclear Information System (INIS)

Wu, Y.

1994-01-01

We derive the occupation-number distribution in a generalized ideal gas of particles obeying fractional statistics, including mutual statistics, by adopting a state-counting definition. When there is no mutual statistics, the statistical distribution interpolates between bosons and fermions, and respects a fractional exclusion principle (except for bosons). Anyons in a strong magnetic field at low temperatures constitute such a physical system. Applications to the thermodynamic properties of quasiparticle excitations in the Laughlin quantum Hall fluid are discussed

New method for 3-dimensional visualization of distributed gas using laser ultrasonic technique; Laser choonpaho ni yoru gas no 3 jigen kukan bunpu keisoku

Energy Technology Data Exchange (ETDEWEB)

Ochiai, M.; Kubo, K.; Kanemoto, S. [Toshiba Corp., Tokyo (Japan); Kokubo, T. [Tokyo Electric Power Co., Inc. (Japan)

1998-11-30

In case that detection of gas leak is performed applying gas sensors, not only sensing for extremely small amount of gas but also measurement of spatial distribution state from the viewpoint of identification of leaking places are important. Meanwhile, it is known that the methane, main component in fuel gas, has characters which absorbs ray having certain specific wavelength and in addition emits its absorbed energy acoustically. As to a photo-acoustic effect in an open space, it is newly found that the signal has a frequency of about 40 kHz and a propagation directivity which is perpendicular to the laser axis. In the feasibility test based on this property, methane molecules are excited by an optical parametric oscillator (OPO) type laser source which has a wavelength of 1330 micron and an output power of about 5 mJ/pulse. Array microphones and 2-dimensional laser scanning system are used for detecting the gas distribution. In the next place, owing to analyzing phase differences of sound wave on the basis of oscillation time of pulse laser, it was verified that the 3-dimensional distribution of gas was measurable. 8 refs., 9 figs., 2 tabs.

Metering; Accurate, fast response the key. [In gas distribution companies

Energy Technology Data Exchange (ETDEWEB)

Johnson, J. (Atlanta Gas Light Co. of Georgia (US))

1990-06-01

Automated meter reading systems are quickly becoming a necessity for local gas distribution companies in the United States, especially as end-users involve themselves in the energy business. With open-access transportation available from the pipelines, balancing on the various systems has become critical, not only from a contractual standpoint but for billing purposes as well. Improved accuracy and decreased time period for accessing gas consumption data are the major motivators in the decision to install a remote data acquisition system. The Metretek system which is one source of this new technology described. (author).

GeoCEGAS: natural gas distribution management system

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Lorena C.J. [Companhia de Gas do Ceara (CEGAS), Fortaleza, CE (Brazil); Targa, Fernando O. [Gestao Empresarial e Informatica Ltda. (GEMPI), Sao Paulo, SP (Brazil)

2009-07-01

This Technical Paper approach the conception, architecture, design, construction, and implementation of GeoCEGAS, a spatially enabled corporate management information system, oriented to store and provide Web access, to information associated with the natural gas distribution network, owned by CEGAS. This paper reports business processes, business entities and business intelligence approached on the project, as well as an overview of system architecture, applications, and technology used on the implementation of GeoCEGAS. Finally, is presented an introduction to the work methodology used, as well a synopsis of benefits achievements. (author)

Report of the experts group on the taxation of the access to gas transport and distribution network

International Nuclear Information System (INIS)

2001-04-01

In the framework of a new french gas industry organization (directive of the 22 june 1998), a concerting mission has been realized on prices taxation for the transport and distribution facilities. The following topics have been debated: the integration and competition of the european gas market, the gas market liberalization consistency and the taxation of transport and distribution network access. (A.L.B.)

ANALYSIS OF DEPENDENCE BETWEEN CAPITAL EXPENDUTURES OF CONSTRUCTION WORKS AND GAS DISTRIBUTION PIPELINE DIAMETER

Directory of Open Access Journals (Sweden)

Tabunshchikov Yuriy Andreevich

2012-10-01

The research also contemplates the structure of expenses associated with the piping of gas distribution networks. Mathematical equations have been derived to perform sufficiently accurate calculations of costs of construction of various types and various lengths of gas pipelines.

Transitory provisions on public gas distribution in the light of the Marzano law

International Nuclear Information System (INIS)

Vedaschi, Arianna

2005-01-01

The article begins by describing community law on public gas distribution service, then it examines legislative decree 164/2000( also called Letta Decree), which implements directive no. 98/30/CE. This directive reforms the gas sector and in particular it reforms the way gas is distributed. Art. 14 of the Letta Decree states that the distribution of natural gas shall be a public service, contractors shall be selected through a public tender and contracts shall be stipulate for a maximum of 12 years. Thus it is evident that the new model is radically different from the previous one. Before, the service was provided by the local authorities (either directly or through a long-term lease); now the new model aims at liberalizing the market by out sourcing gas distribution. Out sourcing is carried out through a public tender and for short periods of time. In order to allow a gradual transition from the old model to the new one, the Letta Decree provides for a transitory period articulated in various phases. This has the aim of guaranteeing a balance between the interest of local authorities, on one hand and the firms that distributed gas before the reform came into effect, on the other. The first part of the article focuses on interpretative problems that arose after law no. 239/2004 (so called Marzano law) was passed. In the second half it compares the different judicial interpretations concerning: a) duration of the transitory period; b) possibility of increasing duration as provided for by art. 15, par.7 of legislative decree 164/2000; c) efficacy of the abrogation of art. 15, par.8 of legislative decree 164/2000 and finally d) whether advanced redemption of the gas distribution service is still possible. With regards to the transitory period, the article compares judgement no. 111/2005 by the Administrative Tribunal of Lombardia, with judgement no. 6187/2005 delivered by the Sixth Section of the State Council. It then argues that the prohibition of concentration has

Use of the truncated shifted Pareto distribution in assessing size distribution of oil and gas fields

Science.gov (United States)

Houghton, J.C.

1988-01-01

The truncated shifted Pareto (TSP) distribution, a variant of the two-parameter Pareto distribution, in which one parameter is added to shift the distribution right and left and the right-hand side is truncated, is used to model size distributions of oil and gas fields for resource assessment. Assumptions about limits to the left-hand and right-hand side reduce the number of parameters to two. The TSP distribution has advantages over the more customary lognormal distribution because it has a simple analytic expression, allowing exact computation of several statistics of interest, has a "J-shape," and has more flexibility in the thickness of the right-hand tail. Oil field sizes from the Minnelusa play in the Powder River Basin, Wyoming and Montana, are used as a case study. Probability plotting procedures allow easy visualization of the fit and help the assessment. ?? 1988 International Association for Mathematical Geology.

Gas puff radiation performance as a function of radial mass distribution

International Nuclear Information System (INIS)

Coleman, Philip L.; Krishnan, Mahadevan; Prasad, Rahul; Qi, Niansheng; Waisman, Eduardo; Failor, B.H.; Levine, J.S.; Sze, H.

2002-01-01

The basic concept of a z-pinch, that JxB forces implode a shell of mass, creating a hot dense plasma on-axis, is coming under closer scrutiny. Wire arrays may start with an initial cold mass in a near 'ideal' shell, but in fact they appear to develop complex radial mass distributions well before the final x-ray output. We consider here the situation for gas puff z-pinches. While the ideal of a gas 'shell' has been the nominal objective for many years, detailed measurements of gas flow show that nozzles used for plasma radiation sources (PRS) also have complex radial distributions. In particular, there are significant data showing that the best x-ray yield comes from the least shell-like distributions. Recent experiments on the Double Eagle generator with argon have further enhanced this view. For those tests with a double 'shell' nozzle, there was a factor of almost 4 increase in yield when the relative mass (outer:inner) in the two shells was changed from 2:1 to less than 1:1. We suggest the following explanation. A configuration with most of its mass at large radii is subject to severe disruption by instabilities during the implosion. A more continuous radial mass distribution with dρ/dr < 0 may mitigate instability development (via the 'snowplow stabilization' mechanism) and thus enhance the thermalization of the kinetic energy of the imploding mass. In addition, the appropriate balance of outer to inner mass maximizes the formation of a strong shock in the core of the pinch that heats the plasma and leads to x-ray emission

The energy density distribution of an ideal gas and Bernoulli’s equations

Science.gov (United States)

Santos, Leonardo S. F.

2018-05-01

This work discusses the energy density distribution in an ideal gas and the consequences of Bernoulli’s equation and the corresponding relation for compressible fluids. The aim of this work is to study how Bernoulli’s equation determines the energy flow in a fluid, although Bernoulli’s equation does not describe the energy density itself. The model from molecular dynamic considerations that describes an ideal gas at rest with uniform density is modified to explore the gas in motion with non-uniform density and gravitational effects. The difference between the component of the speed of a particle that is parallel to the gas speed and the gas speed itself is called ‘parallel random speed’. The pressure from the ‘parallel random speed’ is denominated as parallel pressure. The modified model predicts that the energy density is the sum of kinetic and potential gravitational energy densities plus two terms with static and parallel pressures. The application of Bernoulli’s equation and the corresponding relation for compressible fluids in the energy density expression has resulted in two new formulations. For incompressible and compressible gas, the energy density expressions are written as a function of stagnation, static and parallel pressures, without any dependence on kinetic or gravitational potential energy densities. These expressions of the energy density are the main contributions of this work. When the parallel pressure was uniform, the energy density distribution for incompressible approximation and compressible gas did not converge to zero for the limit of null static pressure. This result is rather unusual because the temperature tends to zero for null pressure. When the gas was considered incompressible and the parallel pressure was equal to static pressure, the energy density maintained this unusual behaviour with small pressures. If the parallel pressure was equal to static pressure, the energy density converged to zero for the limit of the

Constructing a Spatially Resolved Methane Emission Inventory of Natural Gas Production and Distribution over Contiguous United States

Science.gov (United States)

Li, X.; Omara, M.; Adams, P. J.; Presto, A. A.

2017-12-01

Methane is the second most powerful greenhouse gas after Carbon Dioxide. The natural gas production and distribution accounts for 23% of the total anthropogenic methane emissions in the United States. The boost of natural gas production in U.S. in recent years poses a potential concern of increased methane emissions from natural gas production and distribution. The Emission Database for Global Atmospheric Research (Edgar) v4.2 and the EPA Greenhouse Gas Inventory (GHGI) are currently the most commonly used methane emission inventories. However, recent studies suggested that both Edgar v4.2 and the EPA GHGI largely underestimated the methane emission from natural gas production and distribution in U.S. constrained by both ground and satellite measurements. In this work, we built a gridded (0.1° Latitude ×0.1° Longitude) methane emission inventory of natural gas production and distribution over the contiguous U.S. using emission factors measured by our mobile lab in the Marcellus Shale, the Denver-Julesburg Basin, and the Uintah Basin, and emission factors reported from other recent field studies for other natural gas production regions. The activity data (well location and count) are mostly obtained from the Drillinginfo, the EPA Greenhouse Gas Reporting Program (GHGRP) and the U.S. Energy Information Administration (EIA). Results show that the methane emission from natural gas production and distribution estimated by our inventory is about 20% higher than the EPA GHGI, and in some major natural gas production regions, methane emissions estimated by the EPA GHGI are significantly lower than our inventory. For example, in the Marcellus Shale, our estimated annual methane emission in 2015 is 600 Gg higher than the EPA GHGI. We also ran the GEOS-Chem methane simulation to estimate the methane concentration in the atmosphere with our built inventory, the EPA GHGI and the Edgar v4.2 over the nested North American Domain. These simulation results showed differences in

Current distribution measurements inside an electromagnetic plasma gun operated in a gas-puff mode.

Science.gov (United States)

Poehlmann, Flavio R; Cappelli, Mark A; Rieker, Gregory B

2010-12-01

Measurements are presented of the time-dependent current distribution inside a coaxial electromagnetic plasma gun. The measurements are carried out using an array of six axially distributed dual-Rogowski coils in a balanced circuit configuration. The radial current distributions indicate that operation in the gas-puff mode, i.e., the mode in which the electrode voltage is applied before injection of the gas, results in a stationary ionization front consistent with the presence of a plasma deflagration. The effects of varying the bank capacitance, transmission line inductance, and applied electrode voltage were studied over the range from 14 to 112 μF, 50 to 200 nH, and 1 to 3 kV, respectively.

Distributed and decentralized state estimation in gas networks as distributed parameter systems.

Science.gov (United States)

Ahmadian Behrooz, Hesam; Boozarjomehry, R Bozorgmehry

2015-09-01

In this paper, a framework for distributed and decentralized state estimation in high-pressure and long-distance gas transmission networks (GTNs) is proposed. The non-isothermal model of the plant including mass, momentum and energy balance equations are used to simulate the dynamic behavior. Due to several disadvantages of implementing a centralized Kalman filter for large-scale systems, the continuous/discrete form of extended Kalman filter for distributed and decentralized estimation (DDE) has been extended for these systems. Accordingly, the global model is decomposed into several subsystems, called local models. Some heuristic rules are suggested for system decomposition in gas pipeline networks. In the construction of local models, due to the existence of common states and interconnections among the subsystems, the assimilation and prediction steps of the Kalman filter are modified to take the overlapping and external states into account. However, dynamic Riccati equation for each subsystem is constructed based on the local model, which introduces a maximum error of 5% in the estimated standard deviation of the states in the benchmarks studied in this paper. The performance of the proposed methodology has been shown based on the comparison of its accuracy and computational demands against their counterparts in centralized Kalman filter for two viable benchmarks. In a real life network, it is shown that while the accuracy is not significantly decreased, the real-time factor of the state estimation is increased by a factor of 10. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Distribution of natural gas: introduction of the interruptible segment in Sao Paulo, Brazil; Distribuicao de gas natural canalizado: introducao do segmento interruptivel em Sao Paulo

Energy Technology Data Exchange (ETDEWEB)

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

2008-07-01

The principal objective of this paper is the better knowledge and evaluation of the natural gas distribution network interruptible branch. This new service can be appropriate for thermal power generation on flexible dispatch mode, as 'take or pay' contracts surplus jobs. The paper indicates no regulatory restraints in an interruptible network implantation and one can guess that the inexistence of contracts for this service resembles only lack of conjunctural opportunities for this job applications. These difficulties appear both in the supply and distribution branches of the gas business, which prefer flat contracts. The final conclusion is interruptible contracts can be an improvement on the distribution business and certainly can accommodate a suitable demand and supply volumes in the long-term gas market balance. (author)

Dutch gas distribution grid goes green: decision support tool for local biogas utilization

NARCIS (Netherlands)

Weidenaar, Teade; Hoekstra, Sipke; Wolters, Mannes

2011-01-01

A Decision Support Tool (DST) has been developed that will aid Distribution Service Operators (DSOs) in their decision making process on which investments to make in the gas distribution grid in order to facilitate the use of biogas. The DST considers both the conversion of biogas to electricity as

Momentum distributions of selected rare-gas atoms probed by intense femtosecond laser pulses

DEFF Research Database (Denmark)

Abu-Samha, Mahmoud; Madsen, Lars Bojer

2011-01-01

We provide a direct comparison between numerical and experimental (Rudenko et al 2004 J. Phys. B: At. Mol. Opt. Phys. 37 L407) photoelectron momentum distributions in strong-field ionization of selected rare-gas atoms (He, Ne and Ar), probed by femtosecond linearly polarized laser pulses. The cal......We provide a direct comparison between numerical and experimental (Rudenko et al 2004 J. Phys. B: At. Mol. Opt. Phys. 37 L407) photoelectron momentum distributions in strong-field ionization of selected rare-gas atoms (He, Ne and Ar), probed by femtosecond linearly polarized laser pulses....... The calculations are performed by solving the time-dependent Schrödinger equation within the single-active-electron approximation, and focal-volume effects are taken into account by appropriately averaging the results. The resulting momentum distributions are in quantitative agreement with the experimental...

Federative competence conflicts in the natural gas sector distribution; Conflitos de competencias federativas no ambito da distribuicao do gas natural

Energy Technology Data Exchange (ETDEWEB)

Soares, Adriano; Nunes, Alessandro; Nascimento, Juliana; Gois, Luciana; Jardim, Mariana; Moura, Tacio; Campos, Vitor [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Faculdade de Direito

2004-07-01

This essay intends to broach the role played by the federative agents in the natural gas distribution regulation and analyses the conflict arisen from the new script of the article 25, para. 2nd of the Constitution, given by the amendment 5/95. For this, it is necessary to make a brief expose of the different types of non-tributary federative scope distribution and also to talk over about the natural problems from the lack of a clear appraisal of what canalized gas is, defining the state jurisdiction's object. Only then, it is possible to analyse its limits on the canalized gas local services distribution. In this context, it is evident that the role played by the state regulatory agent in promoting a favourable environment to the competition searching for alternatives concerning the problems of the natural monopoly. Equally important, is the study case of Amazonas, in which is enlightened the position of certain agencies and state agents when their constitutional sphere of influence is extrapolated. For the reasons exposed, it is imperative to improve the current forensic model to guarantee a more effective Union participation, at least to assure a minimum level of regulatory uniformization among the federative states. (author)

Gas expanders at M/R Stations in the natural gas distribution network. Pre-project, subreport; Gasexpandere paa distributionsnettets M/R-stationer. Forprojekt, delrapport

Energy Technology Data Exchange (ETDEWEB)

Rasmussen, Niels Bjarne

2010-05-15

Danish Gas Technology Centre has been carrying out a feasibility project to clarify the possibilities of installing gas expanders at M/R-stations (Measuring and Regulating) in the Distribution system of the natural gas grid. A large number of such expanders are installed around the world. The novelty of this project is to use a heat pump to perform the necessary heating of the gas before the expander, and to ''export'' to the electricity grid the remaining electricity from the generator connected to the expander. The present project includes the small M/R-stations at the gas Distribution grid where pressure is reduced from 40 or 20 bar to 4 bar. The preliminary project (year 1 of project) has investigated whether components for such smaller systems can be found, and it has investigated prices for different quantities. A technical feasibility study has been done. Also, preliminary calculations of payback times has been carried out. A large potential of CO{sub 2}-reduction is present with this technology based on saving of natural gas combustion and on new electricity production displacing existing production without any use of primary energy. The main results and conclusions are: 1) There are component suppliers for expander systems suitable to the size of distribution network M/R stations. 2) Pressure regulators provided at the stations are laid out with significant overcapacity, enabling a simplified installation of the expander systems. 3) If the system is being rolled out across the Danish distribution grid, the realistic saving potential is approx. 2.3 million Nm3 of gas per year and a production of almost 40 million kWh of electricity. 4) If the price is 0.60 DKK/kWh for electricity sold, the simple pay-back is 6-7 years on average, covering a variation from 3 to 16 years at the various stations. The smallest stations are omitted. The best stations covering more than half of the gas flow have a pay-back time between 3 and 6 years. 5) The

Electron energy distribution function control in gas discharge plasmas

International Nuclear Information System (INIS)

Godyak, V. A.

2013-01-01

The formation of the electron energy distribution function (EEDF) and electron temperature in low temperature gas discharge plasmas is analyzed in frames of local and non-local electron kinetics. It is shown, that contrary to the local case, typical for plasma in uniform electric field, there is the possibility for EEDF modification, at the condition of non-local electron kinetics in strongly non-uniform electric fields. Such conditions “naturally” occur in some self-organized steady state dc and rf discharge plasmas, and they suggest the variety of artificial methods for EEDF modification. EEDF modification and electron temperature control in non-equilibrium conditions occurring naturally and those stimulated by different kinds of plasma disturbances are illustrated with numerous experiments. The necessary conditions for EEDF modification in gas discharge plasmas are formulated

Power law of distribution of emergency situations on main gas pipeline

Science.gov (United States)

Voronin, K. S.; Akulov, K. A.

2018-05-01

The article presents the results of the analysis of emergency situations on a main gas pipeline. A power law of distribution of emergency situations is revealed. The possibility of conducting further scientific research to ensure the predictability of emergency situations on pipelines is justified.

Distribution for fermionic discrete lattice gas within the canonical ensemble

International Nuclear Information System (INIS)

Kutner, R.; Barszczak, T.

1991-01-01

The distinct deviations from the Fermi-Dirac statistics ascertained recently at low temperatures for a one-dimensional, spinless fermionic discrete lattice gas with conserved number of noninteracting particles hopping on the nondegenerated, well-separated single-particle energy levels are studied in numerical and theoretical terms. The generalized distribution is derived in the form n(h) = {Y h exp[(var-epsilon h -μ)β]+1} -1 valid even in the thermodynamic limit, when the discreteness of the energy levels is kept. This distribution demonstrates good agreement with the data obtained numerically both by the canonical partition-function technique and by Monte Carlo simulation

Optimal Sizing and Placement of Power-to-Gas Systems in Future Active Distribution Networks

DEFF Research Database (Denmark)

Diaz de Cerio Mendaza, Iker; Bhattarai, Bishnu Prasad; Kouzelis, Konstantinos

2015-01-01

Power-to-Gas is recently attracting lots of interest as a new alternative for the regulation of renewable based power system. In cases, where the re-powering of old wind turbines threatens the normal operation of the local distribution network, this becomes especially relevant. However, the design...... -investment cost- and the technical losses in the system under study. The results obtained from the assessed test system show how such non-linear methods could help distribution system operators to obtain a fast and precise perception of what is the best way to integrate the Power-to-Gas facilities...... of medium voltage distribution networks does not normally follow a common pattern, finding a singular and very particular layouts in each case. This fact, makes the placement and dimensioning of such flexible loads a complicated task for the distribution system operator in the future. This paper describes...

Stage 1: Expression of interest and consultation document for natural gas distribution in New Brunswick

International Nuclear Information System (INIS)

1998-01-01

The New Brunswick government intends to award a franchise to establish natural gas distribution in the province. To this end, the province wishes to invite bids from qualified entities to establish gas distribution facilities. The province will select the preferred bidder(s) through a two-stage competitive bidding process. This document details the province's policy objectives, questions and issues to be addressed in stage 1 of the process, and the schedule for the process. Appendices include copies of relevant provincial statutes and regulations

The effect of gas double-dynamic on mass distribution in solid-state fermentation.

Science.gov (United States)

Chen, Hong-Zhang; Zhao, Zhi-Min; Li, Hong-Qiang

2014-05-10

The mass distribution regularity in substrate of solid-state fermentation (SSF) has rarely been reported due to the heterogeneity of solid medium and the lack of suitable instrument and method, which limited the comprehensive analysis and enhancement of the SSF performance. In this work, the distributions of water, biomass, and fermentation product in different medium depths of SSF were determined using near-infrared spectroscopy (NIRS) and the developed models. Based on the mass distribution regularity, the effects of gas double-dynamic on heat transfer, microbial growth and metabolism, and product distribution gradient were systematically investigated. Results indicated that the maximum temperature of substrate and the maximum carbon dioxide evolution rate (CER) were 39.5°C and 2.48mg/(hg) under static aeration solid-state fermentation (SASSF) and 33.9°C and 5.38mg/(hg) under gas double-dynamic solid-state fermentation (GDSSF), respectively, with the environmental temperature for fermentation of 30±1°C. The fermentation production (cellulase activity) ratios of the upper, middle, and lower levels were 1:0.90:0.78 at seventh day under SASSF and 1:0.95:0.89 at fifth day under GDSSF. Therefore, combined with NIRS analysis, gas double-dynamic could effectively strengthen the solid-state fermentation performance due to the enhancement of heat transfer, the stimulation of microbial metabolism and the increase of the homogeneity of fermentation products. Copyright © 2014 Elsevier Inc. All rights reserved.

Health risk assessment linked with purified biogas injection in a natural gas distribution system

International Nuclear Information System (INIS)

Leroux, Carole; Modelon, Hugues; Rousselle, Christophe; Zdanevitch, Isabelle; Evanno, Sebastien

2009-06-01

This document provides for the opinion of the French Agency for Environmental and Occupational Health and Safety (Afsset) expressed after the collective expertise carried out for the evaluation of the health risk linked with biogas injection in the natural gas distribution system. Following the recommendations issued by the Afsset, works have been started in order to collect the sludge-derived biogas and to analyse its composition. These data will be used to assess accidental risks (resulting from biogas valorisation, pipeline transport, industrial and domestic energy valorisation) as well as health risks for users (resulting from the injection in the natural gas distribution system)

Natural gas transmission and distribution model of the National Energy Modeling System

International Nuclear Information System (INIS)

1997-02-01

The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of Integrated Analysis and Forecasting of the Energy Information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. From 1982 through 1993, the Intermediate Future Forecasting System (IFFS) was used by the EIA for its analyses, and the Gas Analysis Modeling System (GAMS) was used within IFFS to represent natural gas markets. Prior to 1982, the Midterm Energy Forecasting System (MEFS), also referred to as the Project Independence Evaluation System (PIES), was employed. NEMS was developed to enhance and update EIA's modeling capability by internally incorporating models of energy markets that had previously been analyzed off-line. In addition, greater structural detail in NEMS permits the analysis of a broader range of energy issues. The time horizon of NEMS is the midterm period (i.e., through 2015). In order to represent the regional differences in energy markets, the component models of NEMS function at regional levels appropriate for the markets represented, with subsequent aggregation/disaggregation to the Census Division level for reporting purposes

Natural gas transmission and distribution model of the National Energy Modeling System

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-02-01

The Natural Gas Transmission and Distribution Model (NGTDM) is the component of the National Energy Modeling System (NEMS) that is used to represent the domestic natural gas transmission and distribution system. NEMS was developed in the Office of Integrated Analysis and Forecasting of the Energy Information Administration (EIA). NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the EIA and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. From 1982 through 1993, the Intermediate Future Forecasting System (IFFS) was used by the EIA for its analyses, and the Gas Analysis Modeling System (GAMS) was used within IFFS to represent natural gas markets. Prior to 1982, the Midterm Energy Forecasting System (MEFS), also referred to as the Project Independence Evaluation System (PIES), was employed. NEMS was developed to enhance and update EIA`s modeling capability by internally incorporating models of energy markets that had previously been analyzed off-line. In addition, greater structural detail in NEMS permits the analysis of a broader range of energy issues. The time horizon of NEMS is the midterm period (i.e., through 2015). In order to represent the regional differences in energy markets, the component models of NEMS function at regional levels appropriate for the markets represented, with subsequent aggregation/disaggregation to the Census Division level for reporting purposes.

The effect of nuclear gas distribution on the mass determination of supermassive black holes

Science.gov (United States)

Mejía-Restrepo, J. E.; Lira, P.; Netzer, H.; Trakhtenbrot, B.; Capellupo, D. M.

2018-01-01

Supermassive black holes reside in the nuclei of most galaxies. During their active episodes, black holes are powered by accretion discs where gravitational energy is converted into radiation1. Accurately determining black hole masses is key to understand how the population evolves over time and how the black holes relate to their host galaxies2-4. Beyond the local universe, z ≳ 0.2, the mass is commonly estimated assuming a virialized motion of gas in the close vicinity of the active black holes, traced through broad emission lines5,6. However, this procedure has uncertainties associated with the unknown distribution of the gas clouds. Here, we show that the black hole masses derived from the properties of the accretion disk and virial mass estimates differ by a factor that is inversely proportional to the width of the broad emission lines. This leads to virial mass misestimations up to a factor of six. Our results suggest that a planar gas distribution that is inclined with respect to the line of sight may account for this effect. However, radiation pressure effects on the distribution of gas can also reproduce our results. Regardless of the physical origin, our findings contribute to mitigating the uncertainties in current black hole mass estimations and, in turn, will help us to better understand the evolution of distant supermassive black holes and their host galaxies.

Conjugated heat transfer and temperature distributions in a gas turbine combustion liner under base-load operation

International Nuclear Information System (INIS)

Kim, Kyung Min; Yun, Nam Geon; Jeon, Yun Heung; Lee, Dong Hyun; Cho, Yung Hee

2010-01-01

Prediction of temperature distributions on hot components is important in development of a gas turbine combustion liner. The present study investigated conjugated heat transfer to obtain temperature distributions in a combustion liner with six combustion nozzles. 3D numerical simulations using FVM commercial codes, Fluent and CFX were performed to calculate combustion and heat transfer distributions. The temperature distributions in the combustor liner were calculated by conjugation of conduction and convection (heat transfer coefficients) obtained by combustion and cooling flow analysis. The wall temperature was the highest on the attachment points of the combustion gas from combustion nozzles, but the temperature gradient was high at the after shell section with low wall temperature

The effects of UV irradiation and gas plasma treatment on living mammalian cells and bacteria: a comparative approach

NARCIS (Netherlands)

Sosnin, E.A.; Stoffels - Adamowicz, E.; Erofeev, M.V.; Kieft, I.E.; Kunts, S.E.

2004-01-01

Living mammalian cells and bacteria were exposed to irradiation from narrow-band UV lamps and treated with a nonthermal gas plasma (plasma needle). The model systems were: Chinese Hamster Ovary (CHO-K1) cells (fibroblasts) and Escherichia Coli bacteria. UV irradiation can lead to cell death

City of Rio de Janeiro's Gas Distribution Network Conversion Program; Projeto de conversao do Sistema de Distribuicao de Gas Canalizado do Rio de Janeiro

Energy Technology Data Exchange (ETDEWEB)

Costa Filho, Manoel A.F.; Pallottino, Joao T. [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil); Margalef, Jose M. [Companhia Distribuidora de Gas do Rio de Janeiro (CEG), Rio de Janeiro, RJ (Brazil)

2004-07-01

This paper discusses the Conversion Program of Rio de Janeiro city, from Town Gas to Natural Gas, looking for evaluating its logistic and benefits, highlighting mainly those related to consumer's safety. The Conversion Program is been implemented under Companhia Distribuidora de Gas do Rio de Janeiro (CEG) supervision, with support of Rio de Janeiro State University (UERJ) in service's quality appraisal and conversion technical procedure elaboration and review. This partnership has started in 2001 and 46% of all residential and commercial customers have already been converted up to July 2004. Conversion Program is divided into the following Phases: Design and Planning, Gas Distribution Network Renovation and Adaptation, Revision, Post-Revision, Conversion and Post-Conversion. This Program may serve as model for similar programs, to be developed in other cities where Natural Gas will be distributed, displacing the Liquefied Petroleum Gas (LPG), and it is one contribution to achieve the federal governmental goal of 12%-NG-participation within Brazilian Energetic Matrix in 2010. (author)

A distribution planning model for natural gas supply chain: A case study

International Nuclear Information System (INIS)

Hamedi, Maryam; Zanjirani Farahani, Reza; Husseini, Mohammad Moattar; Esmaeilian, Gholam Reza

2009-01-01

In this paper, a real-world case study of a natural gas supply chain is investigated. By using concepts related to natural gas industry and the relations among the components of transmission and distribution network, a six-level supply chain has been introduced and presented schematically. The defined supply chain is a single-objective, multi-period, and single-product problem that is formulated as a mixed integer non-linear programming model, which can easily be linearized. The objective of this model is to minimize direct or indirect distribution costs. There are six groups of constraints including capacity, input and output balancing, demand satisfaction, network flow continuity, and relative constraints to the required binary variables. The solution algorithm of the problem is hierarchical; in each step, one section of the problem is solved using an exact method; the outputs of this section are passed to the next relative section as inputs. Finally, it is shown that the problem has been solved in a reasonable time and desirable results are attained. The use of proposed model and its solution approach have been studied in two gas trunk lines, to present the priority of its cost saving

The open access and the natural gas ducts: transport and distribution; O livre acesso e os dutos de gas natural: transporte e distribuicao

Energy Technology Data Exchange (ETDEWEB)

Siqueira, Mariana de; Xavier, Yanko Marcius de Alencar [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

2008-07-01

The present research, attempting for the economic relevance of the natural gas sector, for the lack of a law that disciplines it and, still, for the structural question of the natural gas ducts activities; it analyzes, in a comparative way, the monopoly of the natural gas ducts activities and the mechanisms of competition chosen to brighten up it: the open access and the by pas. The transport and the distribution of the natural gas are really similar, but the ways to insert the competition in its areas are not. (author)

75 FR 36615 - Pipeline Safety: Information Collection Gas Distribution Annual Report Form

Science.gov (United States)

2010-06-28

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration 49 CFR Part 192 [Docket No. PHMSA-RSPA-2004-19854] Pipeline Safety: Information Collection Gas Distribution Annual Report Form AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), DOT. ACTION: Request...

Development and training for the professional of the gas distribution industry in Brazil; Formation des professionnels de l'industrie de la distribution du gaz au Bresil

Energy Technology Data Exchange (ETDEWEB)

Hatsumi Nagato, D. [Workout Energy Business (Brazil)

2000-07-01

This work will present a Training and Development model for professionals of the gas distribution industry. Today's there are not schools developing gas related subjects. It's important to give to the future gas man, the knowledge needed to develop their activities. This can be achieved by focusing on criteria based on The Competency Concept and Learning Organization. To develop professional 'competency' we consider this tree of basic points: to know, to know how to do and wish to do ( willing ). We are going to present the 'minimum' 'competences' required for gas distribution companies and the methods used to qualify people for emergent gas industries, considering basically four professionals groups: workers, technicians, engineers and managers. (author)

Shallow gas charged sediments off the Indian west coast: Genesis and distribution

Digital Repository Service at National Institute of Oceanography (India)

Mazumdar, A.; Peketi, A.; Dewangan, P.; Badesab, F.K.; Ramprasad, T; Ramana, M.V.; Patil, D.J.; Dayal, A.M.

Geophysical and geochemical surveys were carried out off Goa, central west coast of India, to understand the genesis and distribution of shallow gases in marine sediments. Shallow gas charged sediments within the water depths of approx. 15 to 40 m...

The obstacles for the investments in natural gas distribution infrastructure in Brazil; Os obstaculos aos investimentos na rede de distribuicao de gas natural no Brasil

Energy Technology Data Exchange (ETDEWEB)

Almeida, Edmar Luiz Fagundes de; Bueno, Salua Saud; Selles, Vitor [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Economia

2004-07-01

This paper analyses the main obstacles for the expansion of the Brazilian gas distribution pipelines infrastructure. The paper examines the evolution of investments in the gas chain and highlights the existence of an important unbalance between the level of investments in the upstream and transportation segments and the level of investment in the distribution network. It is clear that the level of investments in the distribution segment is not following the pace of expansion of the other segments. Given this conclusion, the paper examines the potential for increasing the level of investment in the distribution segment by augmenting the debt level of distribution companies. By analyzing the main distribution companies' financial statements, the paper shows that they there is room for an expansion in investments through financial leverage. Finally, the paper examines the main financing obstacles that impede the companies to increase their investment level. (author)

Gas Hydrate Formation Probability Distributions: The Effect of Shear and Comparisons with Nucleation Theory.

Science.gov (United States)

May, Eric F; Lim, Vincent W; Metaxas, Peter J; Du, Jianwei; Stanwix, Paul L; Rowland, Darren; Johns, Michael L; Haandrikman, Gert; Crosby, Daniel; Aman, Zachary M

2018-03-13

Gas hydrate formation is a stochastic phenomenon of considerable significance for any risk-based approach to flow assurance in the oil and gas industry. In principle, well-established results from nucleation theory offer the prospect of predictive models for hydrate formation probability in industrial production systems. In practice, however, heuristics are relied on when estimating formation risk for a given flowline subcooling or when quantifying kinetic hydrate inhibitor (KHI) performance. Here, we present statistically significant measurements of formation probability distributions for natural gas hydrate systems under shear, which are quantitatively compared with theoretical predictions. Distributions with over 100 points were generated using low-mass, Peltier-cooled pressure cells, cycled in temperature between 40 and -5 °C at up to 2 K·min -1 and analyzed with robust algorithms that automatically identify hydrate formation and initial growth rates from dynamic pressure data. The application of shear had a significant influence on the measured distributions: at 700 rpm mass-transfer limitations were minimal, as demonstrated by the kinetic growth rates observed. The formation probability distributions measured at this shear rate had mean subcoolings consistent with theoretical predictions and steel-hydrate-water contact angles of 14-26°. However, the experimental distributions were substantially wider than predicted, suggesting that phenomena acting on macroscopic length scales are responsible for much of the observed stochastic formation. Performance tests of a KHI provided new insights into how such chemicals can reduce the risk of hydrate blockage in flowlines. Our data demonstrate that the KHI not only reduces the probability of formation (by both shifting and sharpening the distribution) but also reduces hydrate growth rates by a factor of 2.

Report of study group 5.3 quality assurance for distribution of gas; Rapport du groupe d'etude 5.3 assurance qualite de la distribution des gaz

Energy Technology Data Exchange (ETDEWEB)

Delcour, B.; Masschelin, M.

2000-07-01

The economic and industrial progress of the past few years has prompted many companies to develop quality systems. The gas industry, and in particular the gas distribution companies, have followed this general trend. This report gives an overview of how the gas distribution companies view quality assurance, how they have developed or are currently developing efficient systems, and which problems they have noted in so doing. To achieve an overview of these matters, the IGU's Study Group 5.3 surveyed a number of gas companies using a questionnaire. The purpose of the survey was to analyse approaches to quality in various countries and their impact on customer relations. (authors)

EBR-II Cover Gas Cleanup System upgrade distributed control and front end computer systems

International Nuclear Information System (INIS)

Carlson, R.B.

1992-01-01

The Experimental Breeder Reactor II (EBR-II) Cover Gas Cleanup System (CGCS) control system was upgraded in 1991 to improve control and provide a graphical operator interface. The upgrade consisted of a main control computer, a distributed control computer, a front end input/output computer, a main graphics interface terminal, and a remote graphics interface terminal. This paper briefly describes the Cover Gas Cleanup System and the overall control system; gives reasons behind the computer system structure; and then gives a detailed description of the distributed control computer, the front end computer, and how these computers interact with the main control computer. The descriptions cover both hardware and software

Excellent impact performance of PVC pipeline materials in gas distribution networks after many years of service (CD-rom)

NARCIS (Netherlands)

Visser, Roy; Hermkens, R.M.J.; Wolters, Mannes; Weller, J.; Warnet, Laurent; Beckervordersandforth, C.; Verberg, G.H.B.; Kramer, M.

2008-01-01

It has been about fifty years ago since the first unplasticized poly(vinyl chloride) (uPVC) pipes were installed for use in gas distribution purposes. Currently, about 22,500 km of uPVC is still in use in the Dutch gas distribution network. The pipes were originally designed for a lifetime of 50

Flora robotica -- An Architectural System Combining Living Natural Plants and Distributed Robots

DEFF Research Database (Denmark)

Hamann, Heiko; Divband Soorati, Mohammad; Heinrich, Mary Katherine

2017-01-01

Key to our project flora robotica is the idea of creating a bio-hybrid system of tightly coupled natural plants and distributed robots to grow architectural artifacts and spaces. Our motivation with this ground research project is to lay a principled foundation towards the design and implementation...... of flora robotica, such as the continuous growth process of architectural artifacts and self-repair of living architecture....

Cost efficiency in the Swiss gas distribution sector

International Nuclear Information System (INIS)

Farsi, Mehdi; Filippini, Massimo; Kuenzle, Michael

2007-01-01

This paper studies the cost structure of gas distribution utilities in Switzerland. Three stochastic frontier models are applied to a panel of 26 companies operating from 1996 to 2000. Efficiency is assumed to be constant over time. The analysis highlights the importance of output characteristics such as customer density and network size. The results suggest that the utilities could slightly reduce their operating costs by improving efficiency. There is no evidence of significant unexploited scale economies. However, our analysis indicates that the estimates of scale economies could be sensitive to the assumptions regarding the variation of output with output characteristics

British Gas plans global gas unit expansion

International Nuclear Information System (INIS)

Vielvoye, R.

1991-01-01

This paper reports on developing a global gas business, a British Gas plc's strategy for evolving a state owned U.K. gas company to a privatized worldwide oil and gas giant. By 2000, BG's global gas business is expected to provide 20% of its revenues, compared with 40% each from its exploration and production operations and its U.K. gas business. The global gas unit (GGU) plans to meet its targets mainly through acquiring holdings in gas transmission and distribution companies around the world. In the 12 months since GGU was established, it has made two such major acquisitions in this area. BG acquired Consumers Gas Co., Ltd., Ontario, Canada's biggest natural gas distribution company, for $943.5 million. It also took a 10% stake in Catalana de Gas SA, Barcelona, the largest privately owned gas utility in Spain and in terms of number of customers, the fourth largest in western Europe. BG also is targeting additional revenues from developing gas fired cogeneration systems in developing countries with gas reserves but no established transmission and distribution systems

Design of an inspection robot for small diameter gas distribution mains

NARCIS (Netherlands)

Dertien, Edwin Christian

2014-01-01

The gas distribution network in the Netherlands has a length of roughly 100.000 km in urban areas. This network needs to be monitored constantly and segments need to be replaced when the risks of leaks increase. Since no information can be obtained from inse the network, in this thesis the design of

The distribution of helium isotopes of natural gas and tectonic environment

International Nuclear Information System (INIS)

Sun Mingliang; Tao Mingxin

1993-01-01

Based on the 3 He/ 4 He data of the main oil-gas bearing basins in continental China, a systematic study has been made for the first time on the relations between the space distribution of the helium isotopes of natural gas and the tectonic environment. The average value R-bar of 3 He/ 4 He in eastern China bordering on the Pacific Ocean is 2.08 x 10 -6 >Ra, and that is dualistic mixed helium containing mantle source helium. The R-bar of central and western China is 4.96 x 10 -8 , and that is mainly crust source radioactive helium. The R-bar of Huabei and Zhongyuan oil-gas fields is 8.00 x 10 -7 , and that is a kind of transitional helium intercepted between the eastern region and the central western region of China. On the whole, the 3 He/ 4 He values decrease gradually with the distance from the subduction zone of the Western Pacific Ocean. The results show that the space distributions of the helium isotopes is controlled by the tectonic environment, that is the environment of tensile rift, especially in the neighborhood of deep megafractures advantageous to the rise of mantle source helium, so then and there the 3 He/ 4 He value is the highest; In the most stable craton basins, the value is the lowest and the helium is a typical crust source radioactive one. Between the active area (rift) and stable area, there is the transitional helium and its value is 10 -7 , as is the case in Huabei-Zhongyuan oil-gas field

Measurements of the initial density distribution of gas puff liners by using Rayleigh scattering

Energy Technology Data Exchange (ETDEWEB)

Kalinin, Yu G; Shashkov, A Yu [Kurchatov Institute, Moscow (Russian Federation)

1997-12-31

Rayleigh scattering of a laser beam in a gas jet is proposed for the measurements of initial density distribution of gas-puff liners. The scattering method has several advantages when compared with interferometry. In particular, it provides information on the local gas density, it is more sensitive, and the output data can be absolutely calibrated. Theoretical background of the method is briefly discussed in the paper and the optical setup used in real experiments is described. Imaging of the scattering object make it possible to detect detailed profiles of the investigated gas jet, as illustrated by several examples taken from the experiment. In some cases even the gas jet stratification has been observed. (J.U.). 1 tab., 3 figs., 1 ref.

Investigations on the gas distribution phenomena inside the containment system of LWRs

International Nuclear Information System (INIS)

Manfredini, A.; Oriolo, F.; Villotti, A.

1994-01-01

The importance of mixing and distribution phenomena of hydrogen gas in the reactor safety is emphasised in the advanced reactor concepts, that heavily rely upon the passive cooling systems during a typical severe accident sequence. An advanced methodology for evaluating the temporal and spatial distribution of non condensable gases, including the simulation of buoyancy-driven flows and the effects of the various ESFs activation, in a multi-compartment containment system of a LWR is reviewed. The methodology employs an analogy technique with electrical networks to determine the convection flows among the containment compartments and evaluates, inside a single node, the profile of the vertical concentrations of steam and non condensable gases. The application of the proposed models to simulate the gas distribution phenomena occurring in the HDR E11.2, in the FIPLOC-F2 and in the NUPEC M-7-1 tests demonstrates the importance of these models providing information about local details and spatial distribution. The main results from the post-test analysis performed to simulate the thermal-hydraulic responses of the above mentioned experiments are presented and demonstrate the improvements and the reduction of the error band with respect to the experimental data. This methodology allows to perform a realistic prediction of severe accident sequence inside the containment system of the actual and advanced passive generation of LWRs. (author). 14 refs., 11 figs

Tariff proposal of the Commission of energy regulation from February 28, 2008 for the use of public natural gas distribution networks

International Nuclear Information System (INIS)

2008-01-01

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.)

Numerical solutions of ideal quantum gas dynamical flows governed by semiclassical ellipsoidal-statistical distribution.

Science.gov (United States)

Yang, Jaw-Yen; Yan, Chih-Yuan; Diaz, Manuel; Huang, Juan-Chen; Li, Zhihui; Zhang, Hanxin

2014-01-08

The ideal quantum gas dynamics as manifested by the semiclassical ellipsoidal-statistical (ES) equilibrium distribution derived in Wu et al. (Wu et al . 2012 Proc. R. Soc. A 468 , 1799-1823 (doi:10.1098/rspa.2011.0673)) is numerically studied for particles of three statistics. This anisotropic ES equilibrium distribution was derived using the maximum entropy principle and conserves the mass, momentum and energy, but differs from the standard Fermi-Dirac or Bose-Einstein distribution. The present numerical method combines the discrete velocity (or momentum) ordinate method in momentum space and the high-resolution shock-capturing method in physical space. A decoding procedure to obtain the necessary parameters for determining the ES distribution is also devised. Computations of two-dimensional Riemann problems are presented, and various contours of the quantities unique to this ES model are illustrated. The main flow features, such as shock waves, expansion waves and slip lines and their complex nonlinear interactions, are depicted and found to be consistent with existing calculations for a classical gas.

Numerical solutions of ideal quantum gas dynamical flows governed by semiclassical ellipsoidal-statistical distribution

Science.gov (United States)

Yang, Jaw-Yen; Yan, Chih-Yuan; Diaz, Manuel; Huang, Juan-Chen; Li, Zhihui; Zhang, Hanxin

2014-01-01

The ideal quantum gas dynamics as manifested by the semiclassical ellipsoidal-statistical (ES) equilibrium distribution derived in Wu et al. (Wu et al. 2012 Proc. R. Soc. A 468, 1799–1823 (doi:10.1098/rspa.2011.0673)) is numerically studied for particles of three statistics. This anisotropic ES equilibrium distribution was derived using the maximum entropy principle and conserves the mass, momentum and energy, but differs from the standard Fermi–Dirac or Bose–Einstein distribution. The present numerical method combines the discrete velocity (or momentum) ordinate method in momentum space and the high-resolution shock-capturing method in physical space. A decoding procedure to obtain the necessary parameters for determining the ES distribution is also devised. Computations of two-dimensional Riemann problems are presented, and various contours of the quantities unique to this ES model are illustrated. The main flow features, such as shock waves, expansion waves and slip lines and their complex nonlinear interactions, are depicted and found to be consistent with existing calculations for a classical gas. PMID:24399919

Mitigation of methane emissions in a pilot-scale biocover system at the av miljø landfill, denmark: system design and gas distribution

DEFF Research Database (Denmark)

Kjeldsen, Peter; Skov, B.; Cassini, Filippo

2013-01-01

-passive biocover system was constructed at the AV Miljø landfill. The biocover is fed by landfill gas pumped out of three leachate wells. An innovative gas distribution system was used to overcome the often observed overloaded hot spot areas resulting from uneven gas distribution to the active methane oxidation......Greenhouse gas mitigation at landfills by methane oxidation in engineered biocover systems is believed to be a cost effective technology but so far a full quantitative evaluation of the efficiency of the technology in full scale has only been carried out in a few cases. A third generation semi...... layer. Performed screening of methane and carbon dioxide concentration at the surface of the biocover showed homogenous distributions indicating an even gas distribution. This was supported by result from a performed tracer test where the compound HFC-134a was added to the gas inlet over a 12 day period...

49 CFR 192.197 - Control of the pressure of gas delivered from high-pressure distribution systems.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Control of the pressure of gas delivered from high-pressure distribution systems. 192.197 Section 192.197 Transportation Other Regulations Relating to... STANDARDS Design of Pipeline Components § 192.197 Control of the pressure of gas delivered from high...

Government information report to the parliament. The gas distribution in France; Rapport d'information du gouvernement au parlement. La desserte en gaz du territoire francais

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-11-01

This report evaluates the gas distribution state in France and presents the forecasts of the gas energy use development by the gas utilities users. In this framework the following points are presented: the juridical aspects of the gas distribution, the national plan of distribution, the new legislation occurring from the gas market deregulation and some statistical data on the gas use, consumption and demand in France. (A.L.B.)

Application Status and Problem Investigation of Distributed Generation in China: The Case of Natural Gas, Solar and Wind Resources

Directory of Open Access Journals (Sweden)

Tian-tian Feng

2017-06-01

Full Text Available The development of distributed energy systems in China is one of the important measures to promote the revolution for energy production and its utilization patterns. First of all, we analyze the present application status of China’s distributed generation from three major types: natural gas, photovoltaic, and distributed wind. Secondly, based on the analysis of the project overview, project scale, and project effect in three patterns of distributed generation, we summarize the policy deficiencies and development obstacles. Finally, aiming to promote the development of distributed energy in China, we propose some relevant policies corresponding to countermeasures on the problems existing in the development process of China’s distributed generation of natural gas, photovoltaic, and wind power.

Effects of gas-flow structures on radical and etch-product density distributions on wafers in magnetomicrowave plasma etching reactors

International Nuclear Information System (INIS)

Ikegawa, Masato; Kobayashi, Jun'ichi; Fukuyama, Ryoji

2001-01-01

To achieve high etch rate, uniformity, good selectivity, and etch profile control across large diameter wafers, the distributions of ions, radicals, and etch products in magnetomicrowave high-etch-rate plasma etching reactors must be accurately controlled. In this work the effects of chamber heights, a focus ring around the wafer, and gas supply structures (or gas flow structures) on the radicals and etch products flux distribution onto the wafer were examined using the direct simulation Monte Carlo method and used to determine the optimal reactor geometry. The pressure uniformity on the wafer was less than ±1% when the chamber height was taller than 60 mm. The focus ring around the wafer produced uniform radical and etch-product fluxes but increased the etch-product flux on the wafer. A downward-flow gas-supply structure (type II) produced a more uniform radical distribution than that produced by a radial gas-supply structure (type I). The impact flow of the type II structure removed etch products from the wafer effectively and produced a uniform etch-product distribution even without the focus ring. Thus the downward-flow gas-supply structure (type II) was adopted in the design for the second-generation of a magnetomicrowave plasma etching reactor with a higher etching rate

WARM GAS IN THE VIRGO CLUSTER. I. DISTRIBUTION OF Lyα ABSORBERS

International Nuclear Information System (INIS)

Yoon, Joo Heon; Putman, Mary E.; Bryan, Greg L.; Thom, Christopher; Chen, Hsiao-Wen

2012-01-01

The first systematic study of the warm gas (T = 10 4–5 K) distribution across a galaxy cluster is presented using multiple background QSOs in and around the Virgo Cluster. We detect 25 Lyα absorbers (N HI = 10 13.1–15.4 cm –2 ) in the Virgo velocity range toward 9 of 12 QSO sightlines observed with the Cosmic Origin Spectrograph, with a cluster impact parameter range of 0.36-1.65 Mpc (0.23-1.05 R vir ). Including 18 Lyα absorbers previously detected by STIS or GHRS toward 7 of 11 background QSOs in and around the Virgo Cluster, we establish a sample of 43 absorbers toward a total of 23 background probes for studying the incidence of Lyα absorbers in and around the Virgo Cluster. With these absorbers, we find (1) warm gas is predominantly in the outskirts of the cluster and avoids the X-ray-detected hot intracluster medium (ICM). Also, Lyα absorption strength increases with cluster impact parameter. (2) Lyα-absorbing warm gas traces cold H I-emitting gas in the substructures of the Virgo Cluster. (3) Including the absorbers associated with the surrounding substructures, the warm gas covering fraction (100% for N HI > 10 13.1 cm –2 ) is in agreement with cosmological simulations. We speculate that the observed warm gas is part of large-scale gas flows feeding the cluster both in the ICM and galaxies.

Formation and distribution of large lithologic-stratigraphic oil & gas fields (provinces

Directory of Open Access Journals (Sweden)

Shizhen Tao

2018-02-01

Full Text Available Since the “Tenth Five-Year Plan”, lithologic and stratigraphic reservoirs have been the main contribution of both the discovery as well as reserve and production increase in China; there were about 80% of proven reserves. The typical reservoirs in six major basins in the eastern, central, and western China were adopted as reservoir forming models. The reservoir forming models in three types of slopes, three types of depressions, and three types of lithologic reservoir assemblages have been built on the basis of application of new technologies, physical modeling of reservoir forming mechanism, and investigation to the formation and distribution of the reservoirs. The evaluation methods for large lithologic reservoirs provinces were established based on the forming mechanism and main controlling factors mentioned above. In addition, the study reveals the main controlling factors and the laws of enrichment of two types of stratigraphic reservoirs (pinch-out and weathered karst reservoirs based on the evaluation methods for large stratigraphic reservoir provinces that have been established. By comprehensively understanding the laws of enrichment of lithologic-stratigraphic reservoirs in four types of basins, specific evaluation methods and fine exploration techniques have been developed. The findings led to an exploration direction in the “Thirteenth Five-Year Plan” period. The study supported the exploration and selection of oil and gas plays, as well as promoted the exploration of lithologic and stratigraphic reservoirs. Keywords: Lithologic trap, Stratigraphic trap, Lithostratigraphic reservoir, Large oil and gas field, Large oil and gas province, Formation and distribution, Exploration potential

Distribution and kinematics of atomic and molecular gas inside the solar circle

NARCIS (Netherlands)

Marasco, A.; Fraternali, F.; van der Hulst, J. M.; Oosterloo, T.

2017-01-01

The detailed distribution and kinematics of the atomic and the CO-bright molecular hydrogen in the disc of the Milky Way inside the solar circle are derived under the assumptions of axisymmetry and pure circular motions. We divide the Galactic disc into a series of rings, and assume that the gas in

The consequences of liberalisation of the gas market. Part 5. Distribution companies and small-scale consumers

International Nuclear Information System (INIS)

Van Gelder, J.W.

1999-01-01

In the fifth article in the series on the effects of the liberalization of the Dutch natural gas market the effects on distribution companies and small-scale consumers are discussed. Companies that purchase more than 10 million m 3 of natural gas per year are free to choose another supplier. No later than 2007 the small-scale consumer (annual consumption less than 170,000 m 3 or 50,000 kWh) will be able to choose a gas and electricity supplier. Lower prices are not to be expected, but there will be more service, many new suppliers and a more varied supply of products and services. The energy distribution company will be offering tailor-made work. For small-scale consumers, too, price will be the decisive factor in choosing a supplier. Possibilities for distribution companies in this area are quite restricted, though. Obtaining market power in the buyers' market and cutting costs of operation may force prices down. Scaling-up and (international) cooperation therefore seem to be the best survival strategies in the free market. Sound solvency - which turns out to be present in particular in the smaller distribution companies - makes a company less vulnerable during a prolonged price dip

The RedeGasEnergia and associated technologies to distributed generation, cogeneration and thermoelectric in developing the natural gas in Brazil; A RedeGasEnergia e as tecnologias associadas a geracao distribuida, cogeracao e termeletrica, no desenvolvimento da industria de gas natural no Brasil

Energy Technology Data Exchange (ETDEWEB)

Campos, Michel F. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2004-07-01

From the PETROBRAS Strategic Plan, where 2015 mission and vision are defined, one search to reach the corporative strategy: 'to lead the natural gas market (NG) and to act in a integrated way in the energy market'. Amongst the corporative politics to guide the business strategies, we will be focusing the new businesses development, having as guide line the annual average growth in the domestic demand of NG, 14.2%. The Investment Plan foresees for the energy and gas area investments around US$ 1.8 billion for the 2003/2007 period, being approximately US$ 500 million destined to the conclusion of the already initiated projects of thermoelectric plants. The Strategic Technological Committee of Energy and Gas (COMEG 2003) defined as technologies of interest for PETROBRAS: renewed energies; sustainable development; NG chemical transformation; NG transport, distribution and storage; distributed generation, co-generation and thermoelectric; production, distribution and use of hydrogen as energy vector; industrial, commercial and residential applications of NG; energy efficiency; automotive systems applications; high power electrical systems and environment. The technology explained in this work, for development of the Brazilian Natural Gas Industry, highly compliant with the NG mass use plan, is the distributed generation, co-generation and thermoelectric and its associated technologies (combustion, IGCC, thermoelectric cycles optimization, gas turbines, boiler/heat recovers, microturbines, fuel cells, combustion engines, renewed energies and cold generation among others). There are several business strategies related to this technology: to play in the electric energy business to assure the NG and derivatives market commercialized by PETROBRAS; to play in the development of alternative sources of energy and; to invest in conservation of energy and renewable energy to add value to the company business. The RedeGasEnergia portfolio has 22 projects in this

Characterization of industrial waste from a natural gas distribution company and management strategies: a case study of the East Azerbaijan Gas Company (Iran).

Science.gov (United States)

Taghipour, Hassan; Aslhashemi, Ahmad; Assadi, Mohammad; Khodaei, Firoz; Mardangahi, Baharak; Mosaferi, Mohammad; Roshani, Babak

2012-10-01

Although a fundamental prerequisite for the successful implementation of any waste management plan is the availability of sufficient and accurate data, there are few available studies regarding the characterization and management of gas distribution company waste (GDCW). This study aimed to characterize the industrial waste generated by the East Azerbaijan Gas Distribution Company (EAGDC) and to present environmental management strategies. The EAGDC serves 57 cities and 821 villages with a total population of more than 2.5 million as well as numerous industrial units. The methodology of this study was based on a checklist of data collected from each zone of the company, site visits (observation), and quantity and quality analysis according to the formal data available from different zones. The results indicate that more than 35 different kinds of industrial solid waste are generated in different industrial installations. The most important types of generated waste include empty barrels (including mercaptans, diesel fuel, deionized waters and oil), faulty gas meters and regulators, a variety of industrial oils, sleeves, filter elements and faulty pipes, valves and fittings. The results indicated that, currently, GDCW is generally handled and disposed of with domestic waste, deposited in companies' installation yards and stores or, sometimes, recycled through non-scientific approaches that can create health risks to the public and the environment, even though most of the GDCW was determined to be recyclable or reusable materials. This study concludes that gas distribution companies must pay more attention to source reduction, recycling and reusing of waste to preserve natural resources, landfill space and the environment.

Generic features of the wealth distribution in ideal-gas-like markets.

Science.gov (United States)

Mohanty, P K

2006-07-01

We provide an exact solution to the ideal-gas-like models studied in econophysics to understand the microscopic origin of Pareto law. In these classes of models the key ingredient necessary for having a self-organized scale-free steady-state distribution is the trading or collision rule where agents or particles save a definite fraction of their wealth or energy and invest the rest for trading. Using a Gibbs ensemble approach we could obtain the exact distribution of wealth in this model. Moreover we show that in this model (a) good savers are always rich and (b) every agent poor or rich invests the same amount for trading. Nonlinear trading rules could alter the generic scenario observed here.

The complete information for phenomenal distributed parameter control of multicomponent chemical processes in gas, fluid and solid phase

International Nuclear Information System (INIS)

Niemiec, W.

1985-01-01

A constitutive mathematical model of distributed parameters of multicomponent chemical processes in gas, fluid and solid phase is utilized to the realization of phenomenal distributed parameter control of these processes. Original systems of partial differential constitutive state equations, in the following derivative forms /I/, /II/ and /III/ are solved in this paper from the point of view of information for phenomenal distributed parameter control of considered processes. Obtained in this way for multicomponent chemical processes in gas, fluid and solid phase: -dynamical working space-time characteristics/analytical solutions in working space-time of chemical reactors/, -dynamical phenomenal Green functions as working space-time transfer functions, -statical working space characteristics /analytical solutions in working space of chemical reactors/, -statical phenomenal Green functions as working space transfer functions, are applied, as information for realization of constitutive distributed parameter control of mass, energy and momentum aspects of above processes. Two cases are considered by existence of: A/sup o/ - initial conditions, B/sup o/ - initial and boundary conditions, for multicomponent chemical processes in gas, fluid and solid phase

Visualizing double-stranded RNA distribution and dynamics in living cells by dsRNA binding-dependent fluorescence complementation

Energy Technology Data Exchange (ETDEWEB)

Cheng, Xiaofei [Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3 (Canada); College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, Zhejiang 310036 (China); Deng, Ping; Cui, Hongguang [Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3 (Canada); Wang, Aiming, E-mail: aiming.wang@agr.gc.ca [Southern Crop Protection and Food Research Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3 (Canada)

2015-11-15

Double-stranded RNA (dsRNA) is an important type of RNA that plays essential roles in diverse cellular processes in eukaryotic organisms and a hallmark in infections by positive-sense RNA viruses. Currently, no in vivo technology has been developed for visualizing dsRNA in living cells. Here, we report a dsRNA binding-dependent fluorescence complementation (dRBFC) assay that can be used to efficiently monitor dsRNA distribution and dynamics in vivo. The system consists of two dsRNA-binding proteins, which are fused to the N- and C-terminal halves of the yellow fluorescent protein (YFP). Binding of the two fusion proteins to a common dsRNA brings the split YFP halves in close proximity, leading to the reconstitution of the fluorescence-competent structure and restoration of fluorescence. Using this technique, we were able to visualize the distribution and trafficking of the replicative RNA intermediates of positive-sense RNA viruses in living cells. - Highlights: • A live-cell imaging system was developed for visualizing dsRNA in vivo. • It uses dsRNA binding proteins fused with two halves of a fluorescent protein. • Binding to a common dsRNA enables the reporter to become fluorescent. • The system can efficiently monitor viral RNA replication in living cells.

Visualizing double-stranded RNA distribution and dynamics in living cells by dsRNA binding-dependent fluorescence complementation

International Nuclear Information System (INIS)

Cheng, Xiaofei; Deng, Ping; Cui, Hongguang; Wang, Aiming

2015-01-01

Double-stranded RNA (dsRNA) is an important type of RNA that plays essential roles in diverse cellular processes in eukaryotic organisms and a hallmark in infections by positive-sense RNA viruses. Currently, no in vivo technology has been developed for visualizing dsRNA in living cells. Here, we report a dsRNA binding-dependent fluorescence complementation (dRBFC) assay that can be used to efficiently monitor dsRNA distribution and dynamics in vivo. The system consists of two dsRNA-binding proteins, which are fused to the N- and C-terminal halves of the yellow fluorescent protein (YFP). Binding of the two fusion proteins to a common dsRNA brings the split YFP halves in close proximity, leading to the reconstitution of the fluorescence-competent structure and restoration of fluorescence. Using this technique, we were able to visualize the distribution and trafficking of the replicative RNA intermediates of positive-sense RNA viruses in living cells. - Highlights: • A live-cell imaging system was developed for visualizing dsRNA in vivo. • It uses dsRNA binding proteins fused with two halves of a fluorescent protein. • Binding to a common dsRNA enables the reporter to become fluorescent. • The system can efficiently monitor viral RNA replication in living cells.

78 FR 34703 - Pipeline Safety: Information Collection Activities, Revision to Gas Distribution Annual Report

Science.gov (United States)

2013-06-10

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No. PHMSA-2013-0004] Pipeline Safety: Information Collection Activities, Revision to Gas Distribution Annual Report AGENCY: Pipeline and Hazardous Materials Safety Administration, DOT. ACTION: Notice and request...

THE SMOOTH Mg II GAS DISTRIBUTION THROUGH THE INTERSTELLAR/EXTRA-PLANAR/HALO INTERFACE

Energy Technology Data Exchange (ETDEWEB)

Kacprzak, Glenn G.; Cooke, Jeff; Ryan-Weber, Emma V. [Swinburne University of Technology, VIC 3122 (Australia); Churchill, Christopher W.; Nielsen, Nikole M., E-mail: gkacprzak@astro.swin.edu.au [New Mexico State University, Las Cruces, NM 88003 (United States)

2013-11-01

We report the first measurements of Mg II absorption systems associated with spectroscopically confirmed z ∼ 0.1 star-forming galaxies at projected distances of D < 6 kpc. We demonstrate that the data are consistent with the well-known anti-correlation between rest-frame Mg II equivalent width, W{sub r} (2796), and impact parameter, D, represented by a single log-linear relation derived by Nielsen et al. (MAGIICAT) that converges to ∼2 Å at D = 0 kpc. Incorporating MAGIICAT, we find that the halo gas covering fraction is unity below D ∼ 25 kpc. We also report that our D < 6 kpc absorbers are consistent with the W{sub r} (2796) distributions of the Milky Way interstellar medium (ISM) and ISM+halo. In addition, quasar sight lines of intermediate redshift galaxies with 6 < D < 25 kpc have an equivalent width distribution similar to that of the Milky Way halo, implying that beyond ∼6 kpc, quasar sight lines are likely probing halo gas and not the ISM. As inferred by the Milky Way and our new data, the gas profiles of galaxies can be fit by a single log-linear W{sub r} (2796)-D relation out to large scales across a variety of gas-phase conditions and is maintained through the halo/extra-planar/ISM interfaces, which is remarkable considering their kinematic complexity. These low-redshift, small impact parameter absorption systems are the first steps to bridge the gap between quasar absorption-line studies and H I observations of the circumgalactic medium.

Model for negotiation on contingency plans for distribution of natural gas; Modelo de negociacao para planos de contingencia energetica na area de gas natural

Energy Technology Data Exchange (ETDEWEB)

Sobral, Marcos Felipe Falcao; Morais, Danielle Costa [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

2008-07-01

The high consumption of Natural Gas (NG), the environmental and economic turbulences that occurred in recent years raises questions about the supply of the product in critical situations. Characteristic factors of natural gas, like the high cost of storage, show the need for the establishment of contingency plans that define what procedures should be adopted in the distribution of Natural Gas or redistribute among consumers in times of restriction of supply, substantial increase on demand or reduction in the ability of supply. These plans aim to define in advance the actions that will be adopted, providing business and consumer segments clear rules indicate the time to search for alternative sources in case of crisis. The current models can not yet address the problem of negotiation for the division of the product following the concepts proposed by the science of trading, making things like proportionality and envy-free are not observed. The aim of this study is to propose a model for distribution of quotas for supply of NG between different consumer segments. The proposed algorithm combines the procedures of Knaster, Steinhaus and Divide the Dollar, seeking an allocation that minimize the feeling of jealousy and provide an equitable distribution. (author)

Intelligent system for control and automation of natural gas distribution operation; Sistema inteligente de controle e automacao da operacao de distribuicao de gas natural

Energy Technology Data Exchange (ETDEWEB)

Scucuglia, Jose W.; Souza, Celso C. [Universidade para o Desenvolvimento do Estado e da Regiao do Pantanal (UNIDERP), Campo Grande, MS (Brazil). Curso de Engenharia Eletrica; Patricio, Cristian M.M.M.; Cruz, Lauro C.; Reis, Antonio M.; Cortez, Marco A.A.; Maldonado, Waldemar; Rosa, Willian A. [Universidade para o Desenvolvimento do Estado e da Regiao do Pantanal (UNIDERP), Campo Grande, MS (Brazil). Nucleo de Energia, Automacao e Controle; Teixeira, Marcelo C.M. [UNESP, Ilha Solteira, SP (Brazil). Faculdade de Engenharia Eletrica; Carrasco, Benjamim [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2004-07-01

The present work has as objective to present the development of a dedicated intelligent system to the operation of natural gas distribution. The system adds tools of project, simulation, supervision and control of the flow of natural gas in networks distribution, and is composed of hardware and intelligent software. The developed software possess friendly graphical interface, so that the operator composing visually the distribution network automatically, composes a mathematical model formed by a set of differential equations, being solved by the Newton-Raphson method. This tool of simulation allows, in function of network topology, to get through simulation the conditions gas flow in each point of the loop flow. The micro controlled hardware for acquisition of the data in real time and control of valves was developed. The hardware possesses flexible communication (Radio Frequency, Ethernet and Optical Fiber), intelligence for decision taking and auto test of its proper functioning, so that guarantee security in the operations. An implanted neural system in software propitiates the control monitoring of the characteristics operation and conditions of leak with loss of load, identifying inclusive the place of this leak along of the duct. A system with national technology was gotten, of low cost and high added technological value. (author)

Air quality impacts of projections of natural gas-fired distributed generation

Science.gov (United States)

Horne, Jeremy R.; Carreras-Sospedra, Marc; Dabdub, Donald; Lemar, Paul; Nopmongcol, Uarporn; Shah, Tejas; Yarwood, Greg; Young, David; Shaw, Stephanie L.; Knipping, Eladio M.

2017-11-01

This study assesses the potential impacts on emissions and air quality from the increased adoption of natural gas-fired distributed generation of electricity (DG), including displacement of power from central power generation, in the contiguous United States. The study includes four major tasks: (1) modeling of distributed generation market penetration; (2) modeling of central power generation systems; (3) modeling of spatially and temporally resolved emissions; and (4) photochemical grid modeling to evaluate the potential air quality impacts of increased DG penetration, which includes both power-only DG and combined heat and power (CHP) units, for 2030. Low and high DG penetration scenarios estimate the largest penetration of future DG units in three regions - New England, New York, and California. Projections of DG penetration in the contiguous United States estimate 6.3 GW and 24 GW of market adoption in 2030 for the low DG penetration and high DG penetration scenarios, respectively. High DG penetration (all of which is natural gas-fired) serves to offset 8 GW of new natural gas combined cycle (NGCC) units, and 19 GW of solar photovoltaic (PV) installations by 2030. In all scenarios, air quality in the central United States and the northwest remains unaffected as there is little to no DG penetration in those states. California and several states in the northeast are the most impacted by emissions from DG units. Peak increases in maximum daily 8-h average ozone concentrations exceed 5 ppb, which may impede attainment of ambient air quality standards. Overall, air quality impacts from DG vary greatly based on meteorological conditions, proximity to emissions sources, the number and type of DG installations, and the emissions factors used for DG units.

77 FR 34123 - Pipeline Safety: Public Meeting on Integrity Management of Gas Distribution Pipelines

Science.gov (United States)

2012-06-08

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket No. PHMSA-2012-0100] Pipeline Safety: Public Meeting on Integrity Management of Gas Distribution Pipelines AGENCY: Office of Pipeline Safety, Pipeline and Hazardous Materials Safety Administration, DOT. ACTION...

Study on Gas Field Optimization Distribution with Parameters Adjustment of the Air Duct Outlet for Mechanized Heading Face in Coal Mine

Science.gov (United States)

Gong, Xiao-Yan; Zhang, Xin-Yi; Wu, Yue; Xia, Zhi-Xin; Li, Ying

2017-12-01

At present, as the increasingly drilling dimensions with cross-section expansion and distance prolong in coal mine, the situation of gas accumulation in mechanized heading face becomes severe. In this paper, optimization research of gas distribution was carried out by adjusting parameters of the air duct outlet, including angle, caliber and the front and rear distance of air duct outlet. Mechanized heading face of Ningtiaota coal mine was taken as the research object, simulated and analyzed the problems of original gas field, the reasonable parameters range of the air duct outlet was determined according to the allowable range of wind speed and the effect of gas dilution, the adjustment range of each parameter of the air duct outlet is preliminarily determined. Base on this, the distribution of gas field under different parameters adjustment of air duct outlet was simulated. The specific parameters under the different distance between the air duct outlet and the mechanized heading face were obtained, and a new method of optimizing the gas distribution by adjusting parameters of the air duct outlet was provided.

The national energy policy: a case for gas

International Nuclear Information System (INIS)

Nagle, A.

2001-01-01

During the first half of 2001, Australia's Federal, State and Territory governments through COAG have dedicated considerable time to formulating their initial positions on a national energy policy. The formal development of that policy is expected to be agreed at a mid-year meeting of COAG. Given these many benefits, the AGA believes that a national energy policy should: address regulatory constraints on gas market growth and investment; ensure greenhouse programs and measures encourage fuel switching to cleaner energy sources such as natural gas; make gas market contestability regimes consistent and compatible across the States and Territories; improve and streamline project approval processes along the whole gas chain, from exploration and production through to transmission and distribution; remove regulatory structures and market rules that currently inhibit new gas entrants from entering the electricity generation and cogeneration sectors; introduce appropriate taxation regimes for long lived energy infrastructure assets, particularly following the loss of accelerated depreciation; maximise opportunities for energy choice in urban and regional areas and encourage the development, and market uptake, of new gas technologies

Indices of body fat distribution for assessment of lipodysthrophy in people living with HIV/AIDS

Directory of Open Access Journals (Sweden)

Segatto Aline Francielle

2012-10-01

Full Text Available Abstract Background Metabolic and morphological changes associated with excessive abdominal fat, after the introduction of Antiretroviral Therapy, increase the risk of cardiovascular disease in people living with HIV/AIDS(PLWHA. Accurate methods for body composition analysis are expensive and the use of anthropometric indices is an alternative. However the investigations about this subject in PLWHA are rare, making this research very important for clinical purpose and to advance scientific knowledge. The aim of this study is to correlate results of anthropometric indices of evaluation of body fat distribution with the results obtained by Dual-energy X-Ray Absorptiometry(DEXA, in people living with HIV/AIDS. Methods The sample was of 67 PLWHA(39 male and 28 female, aged 43.6+7.9 years. Body mass index, conicity index, waist/hip ratio, waist/height ratio and waist/thigh were calculated. Separated by sex, each index/ratio was plotted in a scatter chart with linear regression fit and their respective Pearson correlation coefficients. Analyses were performed using Prism statistical program and significance was set at 5%. Results The waist/height ratio presented the highest correlation coefficient, for both male (r=0.80, p Conclusion Anthropometric indices, especially waist/height ratio may be a good alternative way to be used for evaluating the distribution of fat in the abdominal region of adults living with HIV/ADIS.

K-distribution models for gas mixtures in hypersonic nonequilibrium flows

Science.gov (United States)

Bansal, Ankit

Calculation of nonequilibrium radiation field in plasmas around a spacecraft entering into an atmosphere at hypersonic velocities is a very complicated and computationally expensive task. The objective of this Dissertation is to collect state-of-the art spectroscopic data for the evaluation of spectral absorption and emission coefficients of atomic and molecular gases, develop efficient and accurate spectral models and databases, and study the effect of radiation on wall heat loads and flowfield around the spacecraft. The most accurate simulation of radiative transport in the shock layer requires calculating the gas properties at a large number of wavelengths and solving the Radiative Transfer Equation (RTE) in a line-by-line (LBL) fashion, which is prohibitively expensive for coupled simulations. A number of k-distribution based spectral models are developed for atomic lines, continuum and molecular bands that allow efficient evaluation of radiative properties and heat loads in hypersonic shock layer plasma. Molecular radiation poses very different challenges than atomic radiation. A molecular spectrum is governed by simultaneous electronic, vibrational and rotational transitions, making the spectrum very strongly dependent on wavelength. In contrast to an atomic spectrum, where line wings play a major role in heat transfer, most of the heat transfer in molecular spectra occurs near line centers. As the first step, k-distribution models are developed separately for atomic and molecular species, taking advantage of the fact that in the Earth's atmosphere the radiative field is dominated by atomic species (N and O) and in Titan's and Mars' atmospheres molecular bands of CN and CO are dominant. There are a number of practical applications where both atomic and molecular species are present, for example, the vacuum-ultra-violet spectrum during Earth's reentry conditions is marked by emission from atomic bound-bound lines and continuum and simultaneous absorption by

Collection of a radioactive source of $^{83}$Kr to study the gas distribution dynamics in a large GRPC detector

CERN Multimedia

An ultra-granular hadronic calorimeter was built using Glass Resistive Plate Chamber (GRPC) detectors as the sensitive medium. The gas of those detectors of $1 \\times 1$ m$^{2}$ each is constrained to be on one side of the detector. To ensure good gas distribution a prototype was built. Such a scheme could be extended to larger GRPC detectors of more than 2 m$^{2}$ if found efficient. To check the performance a radioactive gas could be used in association with the usual gas mixture used to operate the GRPC. The distribution of the radioactive gas can be monitored thanks to the 1 cm$^2$ resolution provided by the embedded electronics used to read out the detector. The radioactive $^{83}$Kr source (obtained from $^{83}$Rb decay) could be produced at the ISOLDE facility and will be used to study larger GRPC detectors at CERN.

Characterization of gas hydrate distribution using conventional 3D seismic data in the Pearl River Mouth Basin, South China Sea

Science.gov (United States)

Wang, Xiujuan; Qiang, Jin; Collett, Timothy S.; Shi, Hesheng; Yang, Shengxiong; Yan, Chengzhi; Li, Yuanping; Wang, Zhenzhen; Chen, Duanxin

2016-01-01

A new 3D seismic reflection data volume acquired in 2012 has allowed for the detailed mapping and characterization of gas hydrate distribution in the Pearl River Mouth Basin in the South China Sea. Previous studies of core and logging data showed that gas hydrate occurrence at high concentrations is controlled by the presence of relatively coarse-grained sediment and the upward migration of thermogenic gas from the deeper sediment section into the overlying gas hydrate stability zone (BGHSZ); however, the spatial distribution of the gas hydrate remains poorly defined. We used a constrained sparse spike inversion technique to generate acoustic-impedance images of the hydrate-bearing sedimentary section from the newly acquired 3D seismic data volume. High-amplitude reflections just above the bottom-simulating reflectors (BSRs) were interpreted to be associated with the accumulation of gas hydrate with elevated saturations. Enhanced seismic reflections below the BSRs were interpreted to indicate the presence of free gas. The base of the BGHSZ was established using the occurrence of BSRs. In areas absent of well-developed BSRs, the BGHSZ was calculated from a model using the inverted P-wave velocity and subsurface temperature data. Seismic attributes were also extracted along the BGHSZ that indicate variations reservoir properties and inferred hydrocarbon accumulations at each site. Gas hydrate saturations estimated from the inversion of acoustic impedance of conventional 3D seismic data, along with well-log-derived rock-physics models were also used to estimate gas hydrate saturations. Our analysis determined that the gas hydrate petroleum system varies significantly across the Pearl River Mouth Basin and that variability in sedimentary properties as a product of depositional processes and the upward migration of gas from deeper thermogenic sources control the distribution of gas hydrates in this basin.

The gas industry in Japan

International Nuclear Information System (INIS)

Jego, H.

2000-01-01

Though oil is the most widely used primary energy in Japan, its market share is decreasing steadily in favour of other energies such as natural gas. Around 80 % of the gas consumed in Japan is imported in the form of LNG, with locally produced natural gas accounting for 5 % and LPG 12%. Annual LNG supplies now total 48 million tons (720 TWh) and are forecast to rise to 57 million tons over the next ten years. However, only on third of the total volume of LNG, i.e., 242 TWh, is distributed to final consumers. The rest is imported directly by power companies to produce electricity. The 245 gas distribution companies, 70 in the public sector and 175 in the private sector (including three large firms: Tokyo Gas, Osaka Gas and Toho Gas) carry the gas through their own non-interconnected networks to around 25 million customers, though the gas supply area covers only 5 % of the country. This small percentage can be explained partly by Japan's topography: 80 % of the land is covered by mountains. This means that only 20 % of the country is suitable for industrial and residential development. Populations living outside the gas supply areas mainly use LPG. The number of LPG customers totals around 25 million, a similar number to those using mains gas. However, the share of mains gas is increasing each year due to the population increase in urban zones. Though gas represents only 11 % of the energy consumed in Japan, it is nevertheless present on practically all markets and holds the leading position for domestic hot water and cooking in the residential sector. However, for heating, it lags well behind oil. In industry, mains gas covers only 5% of energy needs. However, with the expansion of the pipeline network and market liberalization, the share of gas is set to increase. The price of gas for the residential sector is 2 to 3 times higher than in western countries. This can be attributed to the following factors: most natural gas is imported LNG; unit consumption in the

Decision support in the natural gas distribution process of the Ceara state, Brazil; Apoio a decisao no processo de distribucao do gas natural no ambito do estado do Ceara

Energy Technology Data Exchange (ETDEWEB)

Rabelo, Clarice Augusta Carvalho; Arruda, Joao Bosco Furtado; Nobre, Junior, Ernesto Ferreira [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Engenharia de Transportes. Nucleo de Pesquisa em Logistica, Transporte e Desenvolvimento (NUPELTD); br, barruda@det ufc; br, nobre@det ufc

2003-07-01

The participation of natural gas has improved more and more in Brazilian energetic die. In Ceara, the use of natural gas has increased a lot and the expectations are the best. However it's necessary to guarantee a better infrastructure of distribution and interaction among the actors of the sector. This paper is part of a bigger project that intends to contribute with this improvement through an application of multicriteria techniques in the natural gas distribution process in Ceara. The aim of the project is to choose the market segment to be prioritized due to a possible context of restriction of gas offer in order of its potential demands. Nowadays paper, however, only makes a quick analysis of the actual gas situation in Ceara and a small explanation about multicriteria techniques, specifically, the analytic hierarchy process (AHP). Besides, through a simulation of the problem and an application of the analytic hierarchy process, this paper intends to demonstrate the applicability of these methods in this problem. (author)

Decision support in the natural gas distribution process of the Ceara state, Brazil; Apoio a decisao no processo de distribucao do gas natural no ambito do estado do Ceara

Energy Technology Data Exchange (ETDEWEB)

Rabelo, Clarice Augusta Carvalho; Arruda, Joao Bosco Furtado; Nobre Junior, Ernesto Ferreira [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Engenharia de Transportes. Nucleo de Pesquisa em Logistica, Transporte e Desenvolvimento (NUPELTD)]. E-mail: claricerabelo@aol.com; barruda@det.ufc.br; nobre@det.ufc.br

2003-07-01

The participation of natural gas has improved more and more in Brazilian energetic die. In Ceara, the use of natural gas has increased a lot and the expectations are the best. However it's necessary to guarantee a better infrastructure of distribution and interaction among the actors of the sector. This paper is part of a bigger project that intends to contribute with this improvement through an application of multicriteria techniques in the natural gas distribution process in Ceara. The aim of the project is to choose the market segment to be prioritized due to a possible context of restriction of gas offer in order of its potential demands. Nowadays paper, however, only makes a quick analysis of the actual gas situation in Ceara and a small explanation about multicriteria techniques, specifically, the analytic hierarchy process (AHP). Besides, through a simulation of the problem and an application of the analytic hierarchy process, this paper intends to demonstrate the applicability of these methods in this problem. (author)

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

International Nuclear Information System (INIS)

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

2004-01-01

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

Spectroscopic determination of the magnetic field distribution in a gas-puff Z-pinch plasma

Energy Technology Data Exchange (ETDEWEB)

Gregorian, L; Davara, G; Kroupp, E; Maron, Y [Weizmann Institute of Science, Rehovot (Israel). Dept. of Particle Physics

1997-12-31

The time dependent radial distribution of the magnetic field in a gas-puff Z-pinch plasma has been determined by observing the Zeeman effect on emission lines, allowed for by polarization spectroscopy and high accuracy line-profile measurements. A modeling scheme, based on a 1-D magnetic diffusion equation, is used to fit the experimental data. The plasma conductivity inferred from the field distribution was found to be consistent with the Spitzer conductivity. The current density distribution and the time dependent plasma region in which the entire circuit current flows were determined. (author). 3 figs., 6 refs.

Distribution characteristics of interfacial parameter in downward gas-liquid two-phase flow in vertical circular tube

International Nuclear Information System (INIS)

Liu Guoqiang; Yan Changqi; Tian Daogui; Sun Licheng

2014-01-01

Experimental study was performed on distribution characteristics of interfacial parameters of downward gas-liquid flow in a vertical circular tube with the measurement by a two-sensor optical fiber probe. The test section is a circular pipe with the inner diameter of 50 mm and the length of 2000 mm. The superficial velocities of the gas and the liquid phases cover the ranges of 0.004-0.077 m/s and 0.43-0.71 m/s, respectively. The results show that the distributions of the interfacial parameters in downward bubbly flows are quite different from those in upward bubbly flows. For the case of upward flow, the parameters present the 'wall-peak' or 'core-peak' distributions, but for the case of downward flow, they show 'wall-peak' or 'wide-peak' distributions. The average value of void fraction in vertical downward flow is about 119.6%-145.0% larger than that in upward flow, and the interfacial area concentration is about 18.8%-82.5% larger than that in upward flow. The distribution of interfacial parameters shows an obvious tendency of uniformity. (authors)

Supergalactic studies. II. Supergalactic distribution of the nearest intergalactic gas clouds

International Nuclear Information System (INIS)

de Vaucouleurs, G.; Corwin, H.G. Jr.

1975-01-01

The report by Mathewson, Cleary, and Murray that the nearby ''high velocity'' H i clouds, and in particular the Magellanic Stream, are strongly concentrated toward the supergalactic plane is confirmed. The observed concentration within +-30degree from the supergalactic equator of 21 out of 25 clouds in the north galactic hemisphere and 27 out of 31 clouds in the south galactic hemisphere could occur by chance in less than 7 and 3 percent of random samples from a population having a statistically isotropic Poisson distribution. Since the two galactic hemispheres are substantially independent samples, the combined probability of the chance hypothesis is P -3 . It is found that actually the high-velocity clouds are not so much concentrated toward the supergalactic equator (SGE) as toward the equator of the ''Local Cloud'' of galaxies inclined 14degree to the main supergalactic plane. Both galaxies and H i clouds define the same small circle of maximum concentration and exhibit the same standard deviation (15degree) from it, demonstrating closely related space distributions. It is concluded that, with the possible exception of a few of the largest and probably nearest cloud complexes (MS, AC, C), most of the high-velocity clouds are truly intergalactic and associated with the Local Group and nearer groups of galaxies. Half the population in a total sample of 115 nearby galaxies and intergalactic gas coulds is within 11degree from the Local equator, indicating a half-thickness of approx.0.75 Mpc for the Local Cloud. Intergalactic gas clouds have already been identified near 10 of the nearest galaxies (including our Galaxy and the Magellanic Clouds), most within approx.3 Mpc. The estimated space density of intergalactic gas clouds is Napprox. =20--25 Mpc -3 , in approximate agreement with the densities required by the collision theory of ring galaxies

Biology and distribution of chafers (Coleoptera, Scarabaeidae) living in hollow trees in Sweden.

OpenAIRE

Nilsson, Sven; Baranowski, Rickard; Hedin, Jonas; Jansson, Niklas; Ranius, Thomas

2002-01-01

We review the ecology and distributions of the chafers Liocola marmorata (F.), Gnorimus nobilis (L.) and Gnorimus variabilis (L.) in Sweden based on museum and several large private collections. These species live in hollow deciduous trees, in Sweden especially in oaks. The former and recently documented localities are shown on maps. More than 100 years ago, all the species as well as their habitats were more common in Sweden than today. One problem when interpreting old finds is that hollow ...

MULTI-CRITERIA EVALUATION OF THE EXPANSION OF NATURAL GAS DISTRIBUTION NETWORK BY THE URBAN DYNAMICS

Directory of Open Access Journals (Sweden)

Vanessa M. Massara

2010-01-01

Full Text Available The objective of this work is to analyze the expansion of the infrastructure of natural gas distribution, identifying priorities from large metropolis using the energy planning based on urban design tools like urban dynamics and techniques like AHP (analytic hierarchy process. The methodology proposed uses matrices considering the relations between the concept of urban dynamics, quality of life and the possibilities of natural gas displacing other energy forms. The matrices are made up of information about social and urban development, costs of establishing the infrastructure and projections of the consumption potential in various sectors. Relating the consumption to urban development parameters and the real estate future of the areas in study, the methodology allows indicating for each district, the viability of implementing a gas network. As conclusion, the model presents the integration between the cities profile and the natural gas use, by means of a growth natural gas on districts of São Paulo City as a specific case study.

Systematic studies of the gas humidification effects on spatial PEMFC performance distributions

International Nuclear Information System (INIS)

Reshetenko, Tatyana V.; Bender, Guido; Bethune, Keith; Rocheleau, Richard

2012-01-01

Highlights: ► We investigated impacts of gases humidification on a local PEMFC performance. ► The spatial performance and EIS were studied by a segmented cell system. ► The data were analyzed in the terms of voltage losses. ► A reduction in anode/cathode gases humidification decreased a PEMFC performance. ► A decrease of humidification led to non-uniform performances and voltage losses distributions. - Abstract: The overall current density that is measured in a proton exchange membrane fuel cell (PEMFC) represents the average of the local reaction rates. The overall and local PEMFC performances are determined by several primary loss mechanisms, namely activation, ohmic, and mass transfer. Spatial performance and loss variabilities are significant and depend on the cell design and operating conditions. A segmented cell system was used to quantify different loss distributions along the gas channel to understand the effects of gas humidification. A reduction in the reactant stream humidification decreased cell performance and resulted in non-uniform distributions of overpotentials and performance along the flow field. Activation and ohmic overpotentials increased with a relative humidity decrease due to insufficient membrane and catalyst layer hydration. The relative humidity of the cathode had a strong impact on the mass transfer overpotential due to a lower oxygen permeability through the dry Nafion film covering the catalyst surface. The mass transfer loss distribution was non-uniform, and the mass transfer overpotential increased for the outlet segments due to the oxygen consumption at the inlet segments, which reduced the oxygen concentration downstream, and a progressive water accumulation from upstream segments. Electrochemical impedance spectroscopy (EIS) and an equivalent electric circuit (EEC) facilitated the analysis and interpretation of the segmented cell data.

Analyzing natural gas distribution in Brazil through EVA (Economic Value Added); Analise economico-financeira da industria de distribuicao de gas natural brasileiro sob a otica da geracao de valor

Energy Technology Data Exchange (ETDEWEB)

Marques, Fernando Rodrigues; Parente, Virginia [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Eletrotecnica e Energia

2008-07-01

Although the Brazilian gas market has been showing steady growth and positive news regarding new discoveries, it is not immune to be questioned about its capacity of value generation, and, in particular, if the new companies, operating in distribution have generated it. Value creation, and its management, has become one of the main activities of the modern corporation in order to align the management and shareholders interests. Despite its advancements, the Brazilian NG industry can be considered at its early stages when compared to those of other countries whose industry is more traditional and mature. The process of unbundling of the gas industry, as well as of the public utilities, has become one of the icons of the Brazilian government policies since the mid 90's. Taking into account regulatory change which had only allowed in the last couple of decades the participation of private ownership into the domestic gas market, a follow up of these companies' performances is of interest. Following the concept of value generation, the present study examines the Brazilian gas distribution sector. Based on a detailed analysis of the financial statements of some of the main companies in the sector, that together represent around 68% of the total Brazilian market, this paper verifies whether the gas distribution sector have presented a positive or negative EVA{sup R}, in other words, if, during the period from 2002 to 2007, these newly companies in the gas industry have created or destroyed value in Brazil. (author)

Toward Measuring Galactic Dense Molecular Gas Properties and 3D Distribution with Hi-GAL

Science.gov (United States)

Zetterlund, Erika; Glenn, Jason; Maloney, Phil

2016-01-01

The Herschel Space Observatory's submillimeter dust continuum survey Hi-GAL provides a powerful new dataset for characterizing the structure of the dense interstellar medium of the Milky Way. Hi-GAL observed a 2° wide strip covering the entire 360° of the Galactic plane in broad bands centered at 70, 160, 250, 350, and 500 μm, with angular resolution ranging from 10 to 40 arcseconds. We are adapting a molecular cloud clump-finding algorithm and a distance probability density function distance-determination method developed for the Bolocam Galactic Plane Survey (BGPS) to the Hi-GAL data. Using these methods we expect to generate a database of 105 cloud clumps, derive distance information for roughly half the clumps, and derive precise distances for approximately 20% of them. With five-color photometry and distances, we will measure the cloud clump properties, such as luminosities, physical sizes, and masses, and construct a three-dimensional map of the Milky Way's dense molecular gas distribution.The cloud clump properties and the dense gas distribution will provide critical ground truths for comparison to theoretical models of molecular cloud structure formation and galaxy evolution models that seek to emulate spiral galaxies. For example, such models cannot resolve star formation and use prescriptive recipes, such as converting a fixed fraction of interstellar gas to stars at a specified interstellar medium density threshold. The models should be compared to observed dense molecular gas properties and galactic distributions.As a pilot survey to refine the clump-finding and distance measurement algorithms developed for BGPS, we have identified molecular cloud clumps in six 2° × 2° patches of the Galactic plane, including one in the inner Galaxy along the line of sight through the Molecular Ring and the termination of the Galactic bar and one toward the outer Galaxy. Distances have been derived for the inner Galaxy clumps and compared to Bolocam Galactic Plane

Waiting time distribution for the first conception leading to a live birth

International Nuclear Information System (INIS)

Shrestha, G.; Biswas, S.

1985-01-01

An attempt has been made in this paper to obtain probability model describing the distribution of the waiting time from marriage to first conception based on the data from marriage to first live birth. The speciality of this present approach lies in assuming the marital exposure to be finite which was assumed to be infinite by most of the earlier investigators for mathematical simplicity. Illustration of the applicability of the model on the data pertaining to first order of conception and monthly probability of conception for women married at different age groups have been illustrated in this paper. (author)

Three-dimensional dynamic hip contact area and pressure distribution during activities of daily living.

Science.gov (United States)

Yoshida, H; Faust, A; Wilckens, J; Kitagawa, M; Fetto, J; Chao, Edmund Y-S

2006-01-01

Estimation of the hip joint contact area and pressure distribution during activities of daily living is important in predicting joint degeneration mechanism, prosthetic implant wear, providing biomechanical rationales for preoperative planning and postoperative rehabilitation. These biomechanical data were estimated utilizing a generic hip model, the Discrete Element Analysis technique, and the in vivo hip joint contact force data. The three-dimensional joint potential contact area was obtained from the anteroposterior radiograph of a subject and the actual joint contact area and pressure distribution in eight activities of daily living were calculated. During fast, normal, and slow walking, the peak pressure of moderate magnitude was located at the lateral roof of the acetabulum during mid-stance. In standing up and sitting down, and during knee bending, the peak pressures were located at the edge of the posterior horn and the magnitude of the peak pressure during sitting down was 2.8 times that of normal walking. The peak pressure was found at the lateral roof in climbing up stairs which was higher than that in going down stairs. These results can be used to rationalize rehabilitation protocols, functional restrictions after complex acetabular reconstructions, and prosthetic component wear and fatigue test set up. The same model and analysis can provide further insight to soft tissue loading and pathology such as labral injury. When the pressure distribution on the acetabulum is inverted onto the femoral head, prediction of subchondral bone collapse associated with avascular necrosis can be achieved with improved accuracy.

Design of the ATLAS New Small Wheel Gas Distribution System for the Micromegas Detector Modules

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00084094; The ATLAS collaboration; Alexopoulos, Theodoros; Maltezos, Stavros; Vlachos, Sotirios; Karentzos, Efstathios; Koulouris, Aimilianos; Moschovakos, Paris; Koutelieris, Georgios

2016-01-01

In this work we present and describe the methodology, the particular calculations and simulations accordingly to achieve the appropriate gas flow rates ensuring a uniform gas distribution among the same type of NSW Micromegas modules. The majority of the components used are in large multiplicity so space saving criteria is taking into account and simplicity on the performance with respect to the total cost as well. An appropriate simulation program has been developed for studying the overall gas system determining the gauge pressure, flow rate in the crucial points and branches, respectively. Moreover, an overall prototype configuration, implemented at the NTUA laboratory and based on the Lock-in Amplifier technique to be used in conjunction with the gas leak test via the FRL method is presented. The obtained performances, by means of sensitivity and S/N ratio improvement, are also discussed.

Spatial root distribution of plants growing in vertical media for use in living walls

DEFF Research Database (Denmark)

Jørgensen, Lars; Dresbøll, Dorte Bodin; Thorup-Kristensen, Kristian

2014-01-01

Background and Aims: For plants growing in living walls, the growth potential is correlated to the roots ability to utilize resources in all parts of the growing medium and thereby to the spatial root distribution. The aim of the study was to test how spatial root distribution was affected...... root growth was limited for plants in the middle or lower parts of the medium and 15N measurements confirmed that only plants in the bottom of the box had active roots in the bottom of the medium. The species differed in root architecture and spatial root distribution. Conclusions: The choice...... by growing medium, planting position and competition from other plants. Methods: Five species (Campanula poscharskyana cv. 'Stella', Fragaria vesca cv. 'Småland', Geranium sanguineum cv. 'Max Frei', Sesleria heufleriana and Veronica officinalis cv. 'Allgrün') were grown in three growing media (coir and two...

Tomography for two-dimensional gas temperature distribution based on TDLAS

Science.gov (United States)

Luo, Can; Wang, Yunchu; Xing, Fei

2018-03-01

Based on tunable diode laser absorption spectroscopy (TDLAS), the tomography is used to reconstruct the combustion gas temperature distribution. The effects of number of rays, number of grids, and spacing of rays on the temperature reconstruction results for parallel ray are researched. The reconstruction quality is proportional to the ray number. The quality tends to be smoother when the ray number exceeds a certain value. The best quality is achieved when η is between 0.5 and 1. A virtual ray method combined with the reconstruction algorithms is tested. It is found that virtual ray method is effective to improve the accuracy of reconstruction results, compared with the original method. The linear interpolation method and cubic spline interpolation method, are used to improve the calculation accuracy of virtual ray absorption value. According to the calculation results, cubic spline interpolation is better. Moreover, the temperature distribution of a TBCC combustion chamber is used to validate those conclusions.

Social familiarity governs prey patch-exploitation, -leaving and inter-patch distribution of the group-living predatory mite Phytoseiulus persimilis.

Science.gov (United States)

Zach, Gernot J; Peneder, Stefan; Strodl, Markus A; Schausberger, Peter

2012-01-01

In group-living animals, social interactions and their effects on other life activities such as foraging are commonly determined by discrimination among group members. Accordingly, many group-living species evolved sophisticated social recognition abilities such as the ability to recognize familiar individuals, i.e. individuals encountered before. Social familiarity may affect within-group interactions and between-group movements. In environments with patchily distributed prey, group-living predators must repeatedly decide whether to stay with the group in a given prey patch or to leave and search for new prey patches and groups. Based on the assumption that in group-living animals social familiarity allows to optimize the performance in other tasks, as for example predicted by limited attention theory, we assessed the influence of social familiarity on prey patch exploitation, patch-leaving, and inter-patch distribution of the group-living, plant-inhabiting predatory mite Phytoseiulus persimilis. P. persimilis is highly specialized on herbivorous spider mite prey such as the two-spotted spider mite Tetranychus urticae, which is patchily distributed on its host plants. We conducted two experiments with (1) groups of juvenile P. persimilis under limited food on interconnected detached leaflets, and (2) groups of adult P. persimilis females under limited food on whole plants. Familiar individuals of both juvenile and adult predator groups were more exploratory and dispersed earlier from a given spider mite patch, occupied more leaves and depleted prey more quickly than individuals of unfamiliar groups. Moreover, familiar juvenile predators had higher survival chances than unfamiliar juveniles. We argue that patch-exploitation and -leaving, and inter-patch dispersion were more favorably coordinated in groups of familiar than unfamiliar predators, alleviating intraspecific competition and improving prey utilization and suppression.

Social familiarity governs prey patch-exploitation, -leaving and inter-patch distribution of the group-living predatory mite Phytoseiulus persimilis.

Directory of Open Access Journals (Sweden)

Gernot J Zach

Full Text Available In group-living animals, social interactions and their effects on other life activities such as foraging are commonly determined by discrimination among group members. Accordingly, many group-living species evolved sophisticated social recognition abilities such as the ability to recognize familiar individuals, i.e. individuals encountered before. Social familiarity may affect within-group interactions and between-group movements. In environments with patchily distributed prey, group-living predators must repeatedly decide whether to stay with the group in a given prey patch or to leave and search for new prey patches and groups.Based on the assumption that in group-living animals social familiarity allows to optimize the performance in other tasks, as for example predicted by limited attention theory, we assessed the influence of social familiarity on prey patch exploitation, patch-leaving, and inter-patch distribution of the group-living, plant-inhabiting predatory mite Phytoseiulus persimilis. P. persimilis is highly specialized on herbivorous spider mite prey such as the two-spotted spider mite Tetranychus urticae, which is patchily distributed on its host plants. We conducted two experiments with (1 groups of juvenile P. persimilis under limited food on interconnected detached leaflets, and (2 groups of adult P. persimilis females under limited food on whole plants. Familiar individuals of both juvenile and adult predator groups were more exploratory and dispersed earlier from a given spider mite patch, occupied more leaves and depleted prey more quickly than individuals of unfamiliar groups. Moreover, familiar juvenile predators had higher survival chances than unfamiliar juveniles.We argue that patch-exploitation and -leaving, and inter-patch dispersion were more favorably coordinated in groups of familiar than unfamiliar predators, alleviating intraspecific competition and improving prey utilization and suppression.

Visualization of Gas Distribution in a Model AP-XPS Reactor by PLIF: CO Oxidation over a Pd(100 Catalyst

Directory of Open Access Journals (Sweden)

Jianfeng Zhou

2017-01-01

Full Text Available In situ knowledge of the gas phase around a catalyst is essential to make an accurate correlation between the catalytic activity and surface structure in operando studies. Although ambient pressure X-ray photoelectron spectroscopy (AP-XPS can provide information on the gas phase as well as the surface structure of a working catalyst, the gas phase detected has not been spatially resolved to date, thus possibly making it ambiguous to interpret the AP-XPS spectra. In this work, planar laser-induced fluorescence (PLIF is used to visualize the CO2 distribution in a model AP-XPS reactor, during CO oxidation over a Pd(100 catalyst. The results show that the gas composition in the vicinity of the sample measured by PLIF is significantly different from that measured by a conventional mass spectrometer connected to a nozzle positioned just above the sample. In addition, the gas distribution above the catalytic sample has a strong dependence on the gas flow and total chamber pressure. The technique presented has the potential to increase our knowledge of the gas phase in AP-XPS, as well as to optimize the design and operating conditions of in situ AP-XPS reactors for catalysis studies.

In situ diagnostic of water distribution in thickness direction of MEA by neutron imaging. Focused on characteristics of water distribution in gas diffusion layer

International Nuclear Information System (INIS)

Tasaki, Yutaka; Ichikawa, Yasushi; Kobo, Norio; Shinohara, Kazuhiko; Boillat, Pierre; Kramer, Denis; Scherer, Gunther G.; Lehmann, Eberhard H.

2008-01-01

The mass transfer characteristics of gas diffusion layer (GDL) are closely related to cell performance in PEFC. In this study, In situ diagnostic of water distribution in thickness direction of MEA by Neutron Imaging has been carried out for three MEAs with different GDLs on cathode side as well as I-V characteristics. It was confirmed that this method is useful for analyzing water distribution in thickness direction of MEA. The relationship between I-V characteristics and liquid water distribution has been studied. (author)

Study on distribution and behavior of long-lived radionuclides in surface soil environment

International Nuclear Information System (INIS)

Morita, Shigemitsu; Watanabe, Hitoshi; Katagiri, Hiromi; Akatsu, Yasuo; Ishiguro, Hideharu

1996-01-01

Technetium-99 ( 99 Tc) and Neptunium-237 ( 237 Np) are important radionuclides for environmental assessment around nuclear fuel cycle facilities, because these have long-lives and relatively high mobility in the environment. Therefore, we have been studied the determination, distribution and behavior of such long-lived radionuclides in surface soil environment. A new analytical technique using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was applied to the determination of long-lived radionuclides in environmental samples. The determination method consists of dry ashing, anion exchange and solvent extraction to eliminate the interfering elements and ICP-MS measurement. The sensitivity of this method was 10 to 100,000 times higher, and the counting time was 300 to 100,000 times shorter than the conventional radioanalytical methods. The soil samples were collected at nine points and core soil sample was collected by an electric core sampler at one point. The core soil sample was divided into eight layers. The depth profiles showed that more than 90% of 99 Tc and 237 Np were retained in the surface layer up to 10cm in depth which contained much amount of organic materials. The results suggest that content of organic materials in soil is related to adsorption of 99 Tc and 237 Np onto soil. (author)

Root Growth and Water distribution in living walls

DEFF Research Database (Denmark)

Jørgensen, Lars

of functional living walls and this thesis is a first step of understanding the essential but hidden part inside the growing medium, i.e. the roots. Ensuring successful performance of the plants in a living wall is complex and the choice of growing medium, plant species and planting position are important....... for root growth. This thesis investigates the correlations between the growing media and root and shoots growth, and studies root growth patterns of different plant species and effects of planting position and root interactions of plants growing in living walls. There are a number of challenges with living...... walls; the vertical orientation of the growing medium, plants are growing vertically above or below each other in a limited rooting volume; there is an increased exposure to weather and the plants can react differently to water conditions and competition from other plants. Plant growth is the core...

Linking the Value Assessment of Oil and Gas Firms to Ambidexterity Theory Using a Mixture of Normal Distributions

Directory of Open Access Journals (Sweden)

Casault Sébastien

2016-05-01

Full Text Available Oil and gas exploration and production firms have return profiles that are not easily explained by current financial theory – the variation in their market returns is non-Gaussian. In this paper, the nature and underlying reason for these significant deviations from expected behavior are considered. Understanding these differences in financial market behavior is important for a wide range of reasons, including: assessing investments, investor relations, decisions to raise capital, assessment of firm and management performance. We show that using a “thicker tailed” mixture of two normal distributions offers a significantly more accurate model than the traditionally Gaussian approach in describing the behavior of the value of oil and gas firms. This mixture of normal distribution is also more effective in bridging the gap between management theory and practice without the need to introduce complex time-sensitive GARCH and/or jump diffusion dynamics. The mixture distribution is consistent with ambidexterity theory that suggests firms operate in two distinct states driven by the primary focus of the firm: an exploration state with high uncertainty and, an exploitation (or production state with lower uncertainty. The findings have direct implications on improving the accuracy of real option pricing techniques and futures analysis of risk management. Traditional options pricing models assume that commercial returns from these assets are described by a normal random walk. However, a normal random walk model discounts the possibility of large changes to the marketplace from events such as the discovery of important reserves or the introduction of new technology. The mixture distribution proves to be well suited to inherently describe the unusually large risks and opportunities associated with oil and gas production and exploration. A significance testing study of 554 oil and gas exploration and production firms empirically supports using a mixture

Valuing lives and allocating resources: a defense of the modified youngest first principle of scarce resource distribution.

Science.gov (United States)

Tallman, Ruth

2014-06-01

In this paper, I argue that the 'modified youngest first' principle provides a morally appropriate criterion for making decisions regarding the distribution of scarce medical resources, and that it is morally preferable to the simple 'youngest first' principle. Based on the complete lives system's goal of maximizing complete lives rather than individual life episodes, I argue that essential to the value we see in complete lives is the first person value attributed by the experiencer of that life. For a life to be 'complete' or 'incomplete,' the subject of that life must be able to understand the concept of a complete life, to have started goals and projects, and to know what it would be for that life to be complete. As the very young are not able to do this, it can reasonably be said that their characteristically human lives have not yet begun, giving those accepting a complete lives approach good reason to accept the modified youngest first principle over a simple 'youngest first' approach. © 2012 John Wiley & Sons Ltd.

Technological Innovation in the downstream gas market: Studying the economics of LNG distribution systems with a focus on Norway

International Nuclear Information System (INIS)

Madlener, Reinhard; Jarlsby, Erik

2005-01-01

Prospects for the market diffusion of natural gas, apart from other factors, depend strongly on the limitations set by the supply infrastructure. One of these limitations is determined by the economic viability of extending the distribution infrastructure, which can vary widely depending on the technology chosen and the prevailing local circumstances. While large-scale pipeline-based systems benefit from economies of scale, they require huge initial capital investments and may in certain cases not be economical at all, or only after excessively long payback periods, especially when end-use energy densities are low, growth in demand slow, and the topography difficult. This paper focuses on the economics of adoption and diffusion of innovative small- and medium-scale liquefied natural gas (LNG) distribution systems, as compared to large pipeline-based distribution systems, with a particular focus on the situation in Norway. We address issues such as scale economies, learning effects, technological lock-in, niche market formation, and flexibility. Besides, we look at both the complementarity and competition among grid-based and LNG-based gas distribution systems. Finally, we briefly touch upon tax issues and political considerations. In Norway, the debate on natural gas extension has become controversial and politicized in recent years. On the one hand, certain stakeholders lobby for heavy, state-sponsored investment into one or more pipelines, which would bring large quantities of natural gas to industrial centers, at least some of which have struggled to maintain their market position in the past. On the other hand, there are stakeholders that have argued for the promotion of modular and more flexible small-scale LNG technology systems that could enhance competition in the gas market, and provide end-users with natural gas that would otherwise not be connected to the grid. Under present regulatory and market conditions in Norway, LNG supply to end users is

Running on Fumes: A Critical Look at Mexico’s Natural Gas Transportation and Distribution Infrastructure

Science.gov (United States)

2011-10-27

company’s revenues, but PEMEX has also been hampered in its ability to leverage private investment and ownership in developing and improving...PEMEX offers for gas distribution franchises ; the standard for exclusivity ranges from 20 to 75 years or more in much of the world, but in Mexico... vs . Government,” Revue de l’energie 53, no.1 (2002):648. 12 Juan Rosellon and Jonathan Halpern, “Regulatory Reform in Mexico’s Natural Gas Industry

Experimental optimization of temperature distribution in the hot-gas duct through the installation of internals in the hot-gas plenum of a high-temperature reactor

International Nuclear Information System (INIS)

Henssen, J.; Mauersberger, R.

1990-01-01

The flow conditions in the hot-gas plenum and in the adjacent hot-gas ducts and hot-gas pipes for the high-temperature reactor project PNP-1000 (nuclear process heat project for 1000 MW thermal output) have been examined experimentally. The experiments were performed in a closed loop in which the flow model to be analyzed, representing a 60deg sector of the core bottom of the PNP-1000 with connecting hot-gas piping and diverting arrangements, was installed. The model scale was approx. 1:5.6. The temperature and flow velocity distribution in the hot-gas duct was registered by means of 14 dual hot-wire flowmeters. Through structural changes and/or the installation of internals into the hot-gas plenum of the core bottom offering little flow resistance coolant gas temperature differentials produced in the core could be reduced to such an extent that a degree of mixture amounting to over 80% was achieved at the entrance of the connected heat exchanger systems. Thereby the desired goal of an adequate degree of mixture of the hot gas involving an acceptable pressure loss was reached. (orig.)

Life-cycle analysis of shale gas and natural gas.

Energy Technology Data Exchange (ETDEWEB)

Clark, C.E.; Han, J.; Burnham, A.; Dunn, J.B.; Wang, M. (Energy Systems); ( EVS)

2012-01-27

The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. Using the current state of knowledge of the recovery, processing, and distribution of shale gas and conventional natural gas, we have estimated up-to-date, life-cycle greenhouse gas emissions. In addition, we have developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps - such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings - that need to be addressed further. Our base case results show that shale gas life-cycle emissions are 6% lower than those of conventional natural gas. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty regarding whether shale gas emissions are indeed lower than conventional gas emissions. This life-cycle analysis provides insight into the critical stages in the natural gas industry where emissions occur and where opportunities exist to reduce the greenhouse gas footprint of natural gas.

Spatial and temporal distribution of free-living protozoa in aquatic environments of a Brazilian semi-arid region

Directory of Open Access Journals (Sweden)

Maria Luisa Quinino de Medeiros

2013-08-01

Full Text Available Free-living protozoa organisms are distributed in aquatic environments and vary widely in both qualitative and quantitative terms. The unique ecological functions they exhibit in their habitats help to maintain the dynamic balance of these environments. Despite their wide range and abundance, studies on geographical distribution and ecology, when compared to other groups, are still scarce. This study aimed to identify and record the occurrence of free-living protozoa at three points in Piancó-Piranhas-Açu basin, in a semi-arid area of Rio Grande do Norte (RN state, and to relate the occurrence of taxa with variations in chlorophyll a, pH and temperature in the environments. Samples were collected in the Armando Ribeiro Gonçalves Dam, from two lentic environments upstream and a lotic ecosystem downstream. Sixty-five taxa of free-living protozoa were found. The Student's t-test showed significant inter-variable differences (p <0.05. Similar protozoan species were recorded under different degrees of trophic status according to chlorophyll a concentrations, suggesting the organisms identified are not ideal for indicating trophic level. We hypothesize that food availability, the influence of lentic and lotic systems and the presence of aquatic macrophytes influenced protozoan dynamics during the study period.

Report of the experts group on the taxation of the access to gas transport and distribution network; Rapport du groupe d'experts sur la tarification de l'acces aux reseaux de transport et de distribution de gaz

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-04-01

In the framework of a new french gas industry organization (directive of the 22 june 1998), a concerting mission has been realized on prices taxation for the transport and distribution facilities. The following topics have been debated: the integration and competition of the european gas market, the gas market liberalization consistency and the taxation of transport and distribution network access. (A.L.B.)

Cumulative Distributions and Flow Structure of Two-Passage Shear Coaxial Injector with Various Gas Injection Ratio

Energy Technology Data Exchange (ETDEWEB)

Lee, Inchul; Kim, Dohun; Koo, Jaye [Korea Aerospace Univ., Goyang (Korea, Republic of)

2013-07-15

To verify the effect of inner- and outer-stage gas jets, a shear coaxial injector was designed to analyze the axial velocity profile and breakup phenomenon with an increase in the measurement distance. When the measurement position was increased to Z/d=100, the axial flow showed a fully developed shape due to the momentum transfer, aerodynamic drag effect, and viscous mixing. An inner gas injection, which induces a higher momentum flux ratio near the nozzle, produces the greater shear force on atomization than an outer gas injection. Inner- and Outer-stage gas injection do not affect the mixing between the inner and outer gas flow below Z/d=5. The experiment results showed that the main effect of liquid jet breakup was governed by the gas jet of an inner stage. As the nozzle exit of the outer-stage was located far from the liquid column, shear force and turbulence breaking up of the liquid jets do not fully affect the liquid column. In the case of an inner-stage gas injection momentum flux ratio within 0.84, with the increase in the outer gas momentum flux ratio, the Smd decreases. However, at an inner-stage gas jet momentum flux ratio over 1.38, the Smd shows the similar distribution.

Numerical Investigation of Fuel Distribution Effect on Flow and Temperature Field in a Heavy Duty Gas Turbine Combustor

Science.gov (United States)

Deng, Xiaowen; Xing, Li; Yin, Hong; Tian, Feng; Zhang, Qun

2018-03-01

Multiple-swirlers structure is commonly adopted for combustion design strategy in heavy duty gas turbine. The multiple-swirlers structure might shorten the flame brush length and reduce emissions. In engineering application, small amount of gas fuel is distributed for non-premixed combustion as a pilot flame while most fuel is supplied to main burner for premixed combustion. The effect of fuel distribution on the flow and temperature field related to the combustor performance is a significant issue. This paper investigates the fuel distribution effect on the combustor performance by adjusting the pilot/main burner fuel percentage. Five pilot fuel distribution schemes are considered including 3 %, 5 %, 7 %, 10 % and 13 %. Altogether five pilot fuel distribution schemes are computed and deliberately examined. The flow field and temperature field are compared, especially on the multiple-swirlers flow field. Computational results show that there is the optimum value for the base load of combustion condition. The pilot fuel percentage curve is calculated to optimize the combustion operation. Under the combustor structure and fuel distribution scheme, the combustion achieves high efficiency with acceptable OTDF and low NOX emission. Besides, the CO emission is also presented.

Structure of distribution gas network operation system; Structure du systeme d'exploitation du reseau de distribution du gaz

Energy Technology Data Exchange (ETDEWEB)

Dzirba, E. [Institute of Oil and Gas (Poland); Osiadacz, A. [Warsaw Technical Uniwersity (Poland)

2000-07-01

Distribution networks have become increasingly complex to manage and potentially labor-intensive to operate safely and efficiently. Remote monitoring enables the operator to continually monitor the performance of the system from a central point(s). Where the system operates outside known parameters, the operator can respond very quickly. Remote control provides the additional functionality of enabling plant to be operated from a central point(s) directly or indirectly via operator. Communication can be through one or a combination of different communication media. The whole system for operation of gas distribution network may be looked at as 5-level general model based on ISO proposals adapted for modern control and management systems. The structure and requirements imposed on such a system are described in this paper. (authors)

Health symptoms in residents living near shale gas activity: A retrospective record review from the Environmental Health Project

Directory of Open Access Journals (Sweden)

Beth Weinberger

2017-12-01

Full Text Available Increasing evidence demonstrates an association between health symptoms and exposure to unconventional natural gas development (UNGD. The purpose of this study is to describe the health of adults in communities with intense UNGD who presented for evaluation of symptoms. Records of 135 structured health assessments conducted between February 2012 and October 2015 were reviewed retrospectively. Publicly available data were used to determine proximity to gas wells. Analysis was restricted to records of adults who lived within 1km of a well in Pennsylvania and denied employment in the gas industry (n=51. Symptoms in each record were reviewed by a physician. Symptoms that could be explained by pre-existing or concurrent conditions or social history and those that began or worsened prior to exposure were excluded. Exposure was calculated using date of well drilling within 1km. The number of symptoms/participant ranged from 0 to 19 (mean=6.2; SD=5.1. Symptoms most commonly reported were: sleep disruption, headache, throat irritation, stress or anxiety, cough, shortness of breath, sinus problems, fatigue, nausea, and wheezing. These results are consistent with findings of prior studies using self-report without physician review. In comparison, our results are strengthened by the collection of health data by a health care provider, critical review of symptoms for possible alternative causes, and confirmation of timing of exposure to unconventional natural gas well relative to symptom onset or exacerbation. Our findings confirm earlier studies and add to the growing body of evidence of the association between symptoms and exposure to UNGD. Keywords: Hydraulic fracturing, Health, Fracking, Shale gas, Unconventional gas

The domestic natural gas industry in developing countries

International Nuclear Information System (INIS)

Klass, D.L.; Khan, R.A.; Khwaja, S.

1992-01-01

The domestic natural gas industry has generally exhibited slow growth in most developing countries that are fortunate enough to have sufficient proved gas reserves to meet energy needs. But supportive government policies that promote the use of indigenous reserves are now beginning to have a positive impact in many parts of the world. Supply and distribution infrastructures are being built or modernized. And natural gas is now or will be available at prices that encourage the displacement of competitive fuels in the larger, energy-intensive industrial and power-generation markets of these countries. It is expected that the domestic gas industry in many developing countries will expand at higher rates than in the past. In the next few decades, the resulting benefits will include reductions in oil consumption per capita, improvements in the balance of payments for oil-importing and exporting developing countries, greater efficiency of energy usage and lower energy consumption per output unit, and improved environmental quality. The national economies and living standards will also undergo significant advancement

Gas chromatographic simulated distillation-mass spectrometry for the determination of the boiling point distributions of crude oils

Science.gov (United States)

Roussis; Fitzgerald

2000-04-01

The coupling of gas chromatographic simulated distillation with mass spectrometry for the determination of the distillation profiles of crude oils is reported. The method provides the boiling point distributions of both weight and volume percent amounts. The weight percent distribution is obtained from the measured total ion current signal. The total ion current signal is converted to weight percent amount by calibration with a reference crude oil of a known distillation profile. Knowledge of the chemical composition of the crude oil across the boiling range permits the determination of the volume percent distribution. The long-term repeatability is equivalent to or better than the short-term repeatability of the currently available American Society for Testing and Materials (ASTM) gas chromatographic method for simulated distillation. Results obtained by the mass spectrometric method are in very good agreement with results obtained by conventional methods of physical distillation. The compositional information supplied by the method can be used to extensively characterize crude oils.

Legal and regulatory possibility of connection between interstate natural gas distribution networks instead of constructing transport pipelines; Possibilidade juridoco-regulatoria da conexao interestadual entre redes de distribuicao de gas natural como alternativa a construcao de gasodutos de transporte

Energy Technology Data Exchange (ETDEWEB)

Goncalves, Gustavo Mano [Andrade, Mano - Advogados, Rio de Janeiro, RJ (Brazil)

2012-07-01

According to Revista Brasil Energia (2011a), the local natural gas distribution concessionaire in the State of Sao Paulo Gas Brasiliano Distribuidora - GBD, plans to expand its distribution pipeline network in western Sao Paulo up to the border of the State of Minas Gerais, near the region known as Minas Triangle where a connection with the pipeline network of the State of Minas Gerais' natural gas distribution company, Companhia de Gas de Minas Gerais - GASMIG shall be built in order to supply natural gas to an ammonia plant to be built by PETROBRAS in the City of Uberaba. Still according to the publication, the project described above would be an alternative to the construction of a transportation pipeline that, since the enforcement of the Gas Law - Law No. 11.909/09 (Brasil, 2009), should be subject to concession contracts preceded by a complex, and probably delayed, planning and procurement. However, there is a transportation pipeline project, deriving from the Bolivia-Brazil transportation pipeline near the city of Sao Carlos, in Sao Paulo, crossing the Minas Triangle and finishing in the State of Goias. This project is owned by TGBC Company. The existence of two gas pipeline projects with very similar paths to supply virtually the same regions and based on different regulatory frameworks, one consisting of a connection between the distribution networks of different States and another based on the concept of pipeline transportation of gas under the legal and regulatory federal jurisdiction raises the discussion about the possibility of legal and regulatory interstate connections of distribution pipeline networks as an alternative to planning, allocation and construction of a transportation pipelines. This article aims to examine the legal and regulatory foundations of both alternatives and delineate the limits of performance of States and Federal Government on legislation and regulation concerning the movement of natural gas pipeline through the Country

Detection of ethylene gas in exhaled breath of people living in landfill using CO{sub 2} laser photoacoustic spectroscopy with multicomponent analysis

Energy Technology Data Exchange (ETDEWEB)

Oktafiani, Fitri, E-mail: fitri.oktafiani@mail.ugm.ac.id; Stiyabudi, Rizky; Amin, Mochamad Nurul; Mitrayana [Department of Physics, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara BLS 21, Yogyakarta, 55281 Indonesia (Indonesia)

2016-06-17

The photoacoustic spectrometer (PAS) had been built and the performance had been determined. The research was based on the conversion of the absorbed middle infra red (IR) radiation by gas confined in a closed PAS cell into standing acoustic wave, which could be detected by a suitable electroacoustic transducer such as a microphone. The lowest detection limit for this setup was (57,1 ± 0,3) ppb and quality factor was (14,5 ± 0,6) for ethylene gas in 10P14 CO{sub 2} laser line. Then, this PAS was used to measure of ethylene gas concentration in breath sample of people living in near the Piyungan Bantul Yogyakarta landfill. The result from multicomponent analysis showed that PAS enable to measure the lowest concentration of volatile organic compound (VOC), such as ethylene, which occured on ambien air in Piyungan landfill. Variaty of distance area applied in this research. In the range of ±0,5 km from landfill, we obtained the concentration of ethylene gas concentration for human breath was (1,520 ± 0,002) ppm, while in the range of ±45 km, the ethylene gas concentration for human breath was (0,424 ± 0,002) ppm. Ethylene gas concentrations in exhaled gas decreased along with increasing distance variation of the landfill.

Diffusion of dilute gas in arrays of randomly distributed, vertically aligned, high-aspect-ratio cylinders

Directory of Open Access Journals (Sweden)

Wojciech Szmyt

2017-01-01

Full Text Available In this work we modelled the diffusive transport of a dilute gas along arrays of randomly distributed, vertically aligned nanocylinders (nanotubes or nanowires as opposed to gas diffusion in long pores, which is described by the well-known Knudsen theory. Analytical expressions for (i the gas diffusion coefficient inside such arrays, (ii the time between collisions of molecules with the nanocylinder walls (mean time of flight, (iii the surface impingement rate, and (iv the Knudsen number of such a system were rigidly derived based on a random-walk model of a molecule that undergoes memoryless, diffusive reflections from nanocylinder walls assuming the molecular regime of gas transport. It can be specifically shown that the gas diffusion coefficient inside such arrays is inversely proportional to the areal density of cylinders and their mean diameter. An example calculation of a diffusion coefficient is delivered for a system of titanium isopropoxide molecules diffusing between vertically aligned carbon nanotubes. Our findings are important for the correct modelling and optimisation of gas-based deposition techniques, such as atomic layer deposition or chemical vapour deposition, frequently used for surface functionalisation of high-aspect-ratio nanocylinder arrays in solar cells and energy storage applications. Furthermore, gas sensing devices with high-aspect-ratio nanocylinder arrays and the growth of vertically aligned carbon nanotubes need the fundamental understanding and precise modelling of gas transport to optimise such processes.

One-Way Flow of a Rarefied Gas Induced in a Circular Pipe with a Periodic Temperature Distribution

National Research Council Canada - National Science Library

Aoki, K

2000-01-01

The steady behavior of a rarefied gas in a circular pipe with a saw-like temperature distribution increasing and decreasing periodically in the direction of the pipe axis is investigated numerically...

France's State of the Art Distributed Optical Fibre Sensors Qualified for the Monitoring of the French Underground Repository for High Level and Intermediate Level Long Lived Radioactive Wastes.

Science.gov (United States)

Delepine-Lesoille, Sylvie; Girard, Sylvain; Landolt, Marcel; Bertrand, Johan; Planes, Isabelle; Boukenter, Aziz; Marin, Emmanuel; Humbert, Georges; Leparmentier, Stéphanie; Auguste, Jean-Louis; Ouerdane, Youcef

2017-06-13

This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo's severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA) responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution.

Fast spatially resolved exhaust gas recirculation (EGR) distribution measurements in an internal combustion engine using absorption spectroscopy.

Science.gov (United States)

Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

2015-09-01

Exhaust gas recirculation (EGR) in internal combustion engines is an effective method of reducing NOx emissions while improving efficiency. However, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder non-uniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. A sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in the intake manifold. The study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.

49 CFR 192.1005 - What must a gas distribution operator (other than a master meter or small LPG operator) do to...

Science.gov (United States)

2010-10-01

... Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Gas Distribution Pipeline Integrity Management (IM...

French natural gas industry statistics

International Nuclear Information System (INIS)

2004-01-01

The opening of the French natural gas market is effective since August 2000. In this context, some information, which were published in the past, have become confidential and strategic and can no longer be revealed. The data published in this 2004 edition concern only the years 2001 and 2002 for which data are available. The year 2000 inquiry could not be exploited. A first part presents the natural gas industry in France (consumption, supplies, production, storage, distribution, definition of gases, information sources, energy equivalence, map of transportation networks, storage, compression and production facilities). The statistical data are summarized in the second part in the form of tables: resources and uses in 1999, 2001 and 2002; sectoral use of the network distributed gas since 1972; regional distribution of gas production; domestic production and imports since 1972; sectoral distribution of network gas supplies; pipelines and distribution systems; personnel in the gas industry; gas supplies in 2002; supplies to the residential-tertiary sector in 2002; supplies to the industry in 2002; regional supplies in 2002; share of gas supplies per use in each region; regional distribution of gas supplies for each use. A comparison between the 2002 inquiry results and the provisional status is given in appendix. The 2002 energy status and the 2002 questionnaire are also given in appendixes. (J.S.)

Report of the experts group on the taxation of the access to gas transport and distribution network; Rapport du groupe d'experts sur la tarification de l'acces aux reseaux de transport et de distribution de gaz

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-04-01

In the framework of a new french gas industry organization (directive of the 22 june 1998), a concerting mission has been realized on prices taxation for the transport and distribution facilities. The following topics have been debated: the integration and competition of the european gas market, the gas market liberalization consistency and the taxation of transport and distribution network access. (A.L.B.)

Advanced model for expansion of natural gas distribution networks based on geographic information systems

Energy Technology Data Exchange (ETDEWEB)

Ramirez-Rosado, I.J.; Fernandez-Jimenez, L.A.; Garcia-Garrido, E.; Zorzano-Santamaria, P.; Zorzano-Alba, E. [La Rioja Univ., La Rioja (Spain). Dept. of Electrical Engineering; Miranda, V.; Montneiro, C. [Porto Univ., Porto (Portugal). Faculty of Engineering]|[Inst. de Engenharia de Sistemas e Computadores do Porto, Porto (Portugal)

2005-07-01

An advanced geographic information system (GIS) model of natural gas distribution networks was presented. The raster-based model was developed to evaluate costs associated with the expansion of electrical networks due to increased demand in the La Rioja region of Spain. The model was also used to evaluate costs associated with maintenance and amortization of the already existing distribution network. Expansion costs of the distribution network were modelled in various demand scenarios. The model also considered a variety of technical factors associated with pipeline length and topography. Soil and slope data from previous pipeline projects were used to estimate real costs per unit length of pipeline. It was concluded that results obtained by the model will be used by planners to select zones where expansion is economically feasible. 4 refs., 5 figs.

Influence of shielding gas on fume formation rate and particle size distribution for optimised GMAW

International Nuclear Information System (INIS)

Carpenter, K.R.; Monaghan, B.J.; Nicholson, A.; Cuiuri, D.; Norrish, J.

2010-01-01

The influence of shielding gas on fume formation rate (FFR) and particle size distribution has been investigated by using a technique developed for automatic control of the welding voltage in gas metal arc welding (GMAW). The results for automatic control are compared with the use of a fixed voltage. Significant reductions in FFR and a general decrease in average particle size were observed using the automatic control technique. This reduction in FFR was attributed to improved metal transfer stability, via a reduction in the occurrence of repelled globular transfer, by promoting the 'drop-spray' transfer condition, together with a reduction in the arc length. FFR and particle size were strongly related to the C O2 content of the shielding gas, where FFR increased as percent C 02 increased, due mainly to the dominant influence of C O2 on weld transfer and arc characteristics. The results indicate that FFR for GMAW in the spray regime should be determined by using optimised welding conditions for each shielding gas composition.

France’s State of the Art Distributed Optical Fibre Sensors Qualified for the Monitoring of the French Underground Repository for High Level and Intermediate Level Long Lived Radioactive Wastes

Directory of Open Access Journals (Sweden)

Sylvie Delepine-Lesoille

2017-06-01

Full Text Available This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo’s severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution.

France’s State of the Art Distributed Optical Fibre Sensors Qualified for the Monitoring of the French Underground Repository for High Level and Intermediate Level Long Lived Radioactive Wastes

Science.gov (United States)

Delepine-Lesoille, Sylvie; Girard, Sylvain; Landolt, Marcel; Bertrand, Johan; Planes, Isabelle; Boukenter, Aziz; Marin, Emmanuel; Humbert, Georges; Leparmentier, Stéphanie; Auguste, Jean-Louis; Ouerdane, Youcef

2017-01-01

This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo’s severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA) responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution. PMID:28608831

Analysis of intergranular fission-gas bubble-size distributions in irradiated uranium-molybdenum alloy fuel

Energy Technology Data Exchange (ETDEWEB)

Rest, J. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)], E-mail: jrest@anl.gov; Hofman, G.L.; Kim, Yeon Soo [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States)

2009-04-15

An analytical model for the nucleation and growth of intra and intergranular fission-gas bubbles is used to characterize fission-gas bubble development in low-enriched U-Mo alloy fuel irradiated in the advanced test reactor in Idaho as part of the Reduced Enrichment for Research and Test Reactor (RERTR) program. Fuel burnup was limited to less than {approx}7.8 at.% U in order to capture the fuel-swelling stage prior to irradiation-induced recrystallization. The model couples the calculation of the time evolution of the average intergranular bubble radius and number density to the calculation of the intergranular bubble-size distribution based on differential growth rate and sputtering coalescence processes. Recent results on TEM analysis of intragranular bubbles in U-Mo were used to set the irradiation-induced diffusivity and re-solution rate in the bubble-swelling model. Using these values, good agreement was obtained for intergranular bubble distribution compared against measured post-irradiation examination (PIE) data using grain-boundary diffusion enhancement factors of 15-125, depending on the Mo concentration. This range of enhancement factors is consistent with values obtained in the literature.

Analysis of intergranular fission-gas bubble-size distributions in irradiated uranium-molybdenum alloy fuel

Science.gov (United States)

Rest, J.; Hofman, G. L.; Kim, Yeon Soo

2009-04-01

An analytical model for the nucleation and growth of intra and intergranular fission-gas bubbles is used to characterize fission-gas bubble development in low-enriched U-Mo alloy fuel irradiated in the advanced test reactor in Idaho as part of the Reduced Enrichment for Research and Test Reactor (RERTR) program. Fuel burnup was limited to less than ˜7.8 at.% U in order to capture the fuel-swelling stage prior to irradiation-induced recrystallization. The model couples the calculation of the time evolution of the average intergranular bubble radius and number density to the calculation of the intergranular bubble-size distribution based on differential growth rate and sputtering coalescence processes. Recent results on TEM analysis of intragranular bubbles in U-Mo were used to set the irradiation-induced diffusivity and re-solution rate in the bubble-swelling model. Using these values, good agreement was obtained for intergranular bubble distribution compared against measured post-irradiation examination (PIE) data using grain-boundary diffusion enhancement factors of 15-125, depending on the Mo concentration. This range of enhancement factors is consistent with values obtained in the literature.

Survey of stranded gas and delivered costs to Europe of selected gas resources

Science.gov (United States)

Attanasi, E.D.; Freeman, P.A.

2011-01-01

Two important trends affecting the expected growth of global gas markets are (1) the shift by many industrialized countries from coal-fired electricity generation to the use of natural gas to generate electricity and (2) the industrialization of the heavily populated Asian countries of India and China. This paper surveys discovered gas in stranded conventional gas accumulations and presents estimates of the cost of developing and producing stranded gas in selected countries. Stranded gas is natural gas in discovered or identified fields that is not currently commercially producible for either physical or economic reasons. Published reserves of gas at the global level do not distinguish between volumes of gas in producing fields and volumes in nonproducing fields. Data on stranded gas reported here-that is the volumes, geographical distribution, and size distributions of stranded gas fields at the country and regional level-are based on the examination of individual-field data and represent a significant improvement in information available to industry and government decision makers. Globally, stranded gas is pervasive, but large volumes in large accumulations are concentrated in only a few areas. The cost component of the paper focuses on stranded conventional gas accumulations in Africa and South America that have the potential to augment supplies to Europe. The methods described for the computation of extraction and transport costs are innovative in that they use information on the sizes and geographical distribution of the identified stranded gas fields. The costs are based on industry data specific to the country and geologic basin where the stranded gas is located. Gas supplies to Europe can be increased significantly at competitive costs by the development of stranded gas. Net extraction costs of producing the identified gas depend critically on the natural-gas-liquids (NGLs) content, the prevailing prices of liquids, the size of the gas accumulation, and the

Species at risk setback distances : the effects of shallow gas activity on the distribution of grassland birds

International Nuclear Information System (INIS)

Linnen, C.

2006-01-01

The effects of shallow gas activity on the distribution of grassland birds was discussed in this presentation. The overall purpose of the study was to examine the effects of minimal disturbance gas wells and associated activity on species richness; effects on species abundance; and effects on the occurrence of species. The presentation provided several hypotheses, including that species richness would increase with increasing distance from gas wells and trails; that abundance and occurrence of sensitive species would increase with distance from gas wells and trails; and that abundance and occurrence of brood parasites and predators would decrease with increasing distance from gas wells and trails. The presentation illustrated the study area and study design. Several graphs representing the study results were also presented. Bird species that were examined included the abundance and occurrence of western meadowlark; horned lark; chestnut-collared longspur; clay-coloured sparrow; vesper sparrow; sprague pipit; savannah sparrow; grasshopper sparrow; baird sparrow; and brown-headed cowbird. A summary slide was also presented that concluded that species richness did not vary with distance from gas development and that brown-headed cowbirds tended to favour areas with gas development and interior habitats. tabs., figs

Evaluation of pulmonary gas distribution by the 133Xe washout curve

International Nuclear Information System (INIS)

Sato, Masao; Katsuragawa, Shigehiko

1989-01-01

The pulmonary mixing index (PMI) and ΔN 2 derived from an N 2 washout curve by the multiple-breath method, and the K 1 /K 4 ratio (K 1 , K 4 are the rate constant of washout obtained from the fast space and slow space, respectively) derived from regional 133 Xe washout curves were evaluated in 12 healthy subjects and 22 subjects with pulmonary disease, who included 12 subjects with chronic obstructive pulmonary disease (COPD), 5 subjects with pulmonary fibrosis (PF) and 5 subjects with bronchial asthma (BA). The results were as follows: 1) PMI was 0.68±0.31% (mean±SD) in the PF group, 1.34±0.40% in the BA group and 8.63±5.01% in the COPD group. The ΔN 2 was 0.20±0.11%, 0.64±0.24% and 5.96±4.21%, respectively. 2) The K 1 /K 4 ratio in the right lung was linearly correlated with that of the left lung (r=0.84, p 1 /K 4 ratio (mean±SE) in healthy subjects was lowest in the basal region of the right lung. 4) The regional gas distribution score (RGDS) derived from the regional K 1 /K 4 ratios was 18.8±0.9 (mean±SE) in the healthy 12 subjects, 19.0±1.2 in the PF group, 11.8±1.8 in the BA group and 6.5±0.6 in the COPD group. It was concluded that RGDS was more sensitive and useful parameter than PMI and ΔN 2 for detecting the disturbance of pulmonary gas distribution. (author)

Non-equilibrium thermodynamics and energy distribution function of neutron gas in constant power reactor under coupling of neutrons and medium

International Nuclear Information System (INIS)

Hayasaka, Hideo

1983-01-01

The thermodynamics and the energy distribution function of the neutron gas in a constant power reactor are considered, taking into account the burn-up of fuel. To separate the secular motion of neutrons owing to fuel burn-up and the microscopic fluctuations of neutrons around this motion, a long time of the order of several months is divided into m equal intervals, and the respective states corresponding to m small time intervals are treated as quasi-stationary states. The local energy distribution function of the neutron gas in the quasi-stationary state is given by a generalized Boltzmann distribution specified by the respective generalized activity coefficient for each subsystem. The effects of fuel burn-up on the respective distribution functions for successive small time intervals are taken into account through various quantities relating to reactor physics, depending upon the fuel burn-up, by successive approximation. (author)

Joint Costs in Electricity and Natural Gas Distribution Infrastructures: The Role of Urban Factors

Directory of Open Access Journals (Sweden)

Muzeyyen Anil Senyel

2018-04-01

Full Text Available This paper analyzes the joint cost structure of electricity and natural gas distribution investments. Assessing the joint costs is critical for urban development and public policy regarding competition at the local level. The paper accounts for the urban and geographic factors at the local level, while the previous literature primarily used company-level data with a few or no site-specific variables in joint cost analyses. An empirical analysis of the multi-utility capital costs suggests that the local urban and geographic conditions affect such costs, with economies of scope present in electricity and natural gas both in terms of total costs and underground investment costs. Hence, the joint service provision makes economic and environmental sense for urban policy makers.

Fuel flexible distributed combustion for efficient and clean gas turbine engines

International Nuclear Information System (INIS)

Khalil, Ahmed E.E.; Gupta, Ashwani K.

2013-01-01

Highlights: • Examined distributed combustion for gas turbines applications using HiTAC. • Gaseous, liquid, conventional and bio-fuels are examined with ultra-low emissions. • Novel design of fuel flexibility without any atomizer for liquid fuel sprays. • Demonstrated fuel flexibility with emissions x and CO, low noise, enhanced stability, higher efficiency and alleviation of combustion instability. Distributed reaction conditions were achieved using swirl for desirable controlled mixing between the injected air, fuel and hot reactive gases from within the combustor prior to mixture ignition. In this paper, distributed combustion is further investigated using a variety of fuels. Gaseous (methane, diluted methane, hydrogen enriched methane and propane) and liquid fuels, including both traditional (kerosene) and alternate fuels (ethanol) that cover a wide range of calorific values are investigated with emphasis on pollutants emission and combustor performance with each fuel. For liquid fuels, no atomization or spray device was used. Performance evaluation with the different fuels was established to outline the flexibility of the combustor using a wide range of fuels of different composition, phase and calorific value with specific focus on ultra-low pollutants emission. Results obtained on pollutants emission and OH * chemiluminescence for the specific fuels at various equivalence ratios are presented. Near distributed combustion conditions with less than 8 PPM of NO emission were demonstrated under novel premixed conditions for the various fuels tested at heat (energy) release intensity (HRI) of 27 MW/m 3 -atm. and a rather high equivalence ratio of 0.6. Higher equivalence ratios lacked favorable distributed combustion conditions. For the same conditions, CO emission varied for each fuel; less than 10 ppm were demonstrated for methane based fuels, while heavier liquid fuels provided less than 40 ppm CO emissions. Lower emissions of NO ( x can be possible by

Productivity Growth and the General X-factor in Austria´s Gas Distribution

OpenAIRE

Gugler, Klaus; Liebensteiner, Mario

2016-01-01

We estimate cost functions to derive productivity growth using a unique database on costs and outputs of essentially all regulated Austrian gas distribution companies over the period 2002-2013, covering the times before and after the introduction of incentive regulation in 2008. We estimate a concave relation between total costs and time, and a significant one-off but permanent reduction in real costs after an imposed reduction in granted costs in the course of the introduction of incentive r...

Gas-particle phase partitioning and particle size distribution of chlorinated and brominated polycyclic aromatic hydrocarbons in haze.

Science.gov (United States)

Jin, Rong; Zheng, Minghui; Yang, Hongbo; Yang, Lili; Wu, Xiaolin; Xu, Yang; Liu, Guorui

2017-12-01

Chlorinated and brominated polycyclic aromatic hydrocarbons (Cl/Br-PAHs) are emerging semi-volatile organic pollutants in haze-associated particulate matter (PM). Their gas-particle phase partitioning and distribution among PM fractions have not been clarified. Clarification would increase understanding of atmospheric behavior and health risks of Cl/Br-PAHs. In this study, samples of the gas phase and 4 PM phases (aerodynamic diameters (d ae ) > 10 μm, 2.5-10 μm, 1.0-2.5 μm, and <1.0 μm) were collected simultaneously during haze events in Beijing and analyzed. Normalized histogram distribution indicated that the Cl/Br-PAHs tended to adhere to fine particles. Over 80% of the Cl-PAHs and 70% of the Br-PAHs were associated with fine PM (d ae  < 2.5 μm). The gas-particle phase partitioning and PM distribution of Cl/Br-PAHs when heating of buildings was required, which was associated with haze events, were obviously different from those when heating was not required. The relationship between the logarithmic geometric mean diameters of the Cl/Br-PAH congeners and reciprocal of the temperature (1/T) suggested that low air temperatures during the heating period could lead to high proportions of Cl/Br-PAHs in the fine particles. Increased coal burning during the heating period also contributed to high Cl/Br-PAH loads in the fine particles. Copyright © 2017 Elsevier Ltd. All rights reserved.

Regulator preferences and utility prices: evidence from natural gas distribution utilities

International Nuclear Information System (INIS)

Klein, C.C.; Sweeney, G.H.

1999-01-01

We investigate the determinants of regulators' relative weighting of the social welfare of customer groups and utilities using panel data on natural gas distribution utilities in the US state of Tennessee. In contrast to previous empirical work on cross-sections of electric utilities, our results are statistically robust and consistent with the interest group theory of regulation. Intervention in rate cases, settlement vs. litigation of cases, and prices of alternative energy sources, as well as the size characteristics of customer groups and the firm, are significant determinants of the elasticity-weighted price-cost margin (Ramsey number) for each group. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

Cooling of Gas Turbines. 6; Computed Temperature Distribution Through Cross Section of Water-Cooled Turbine Blade

Science.gov (United States)

Livingood, John N. B.; Sams, Eldon W.

1947-01-01

A theoretical analysis of the cross-sectional temperature distribution of a water-cooled turbine blade was made using the relaxation method to solve the differential equation derived from the analysis. The analysis was applied to specific turbine blade and the studies icluded investigations of the accuracy of simple methods to determine the temperature distribution along the mean line of the rear part of the blade, of the possible effect of varying the perimetric distribution of the hot gas-to -metal heat transfer coefficient, and of the effect of changing the thermal conductivity of the blade metal for a constant cross sectional area blade with two quarter inch diameter coolant passages.

Local ISM 3D Distribution and Soft X-ray Background Inferences for Nearby Hot Gas

Science.gov (United States)

Puspitarini, L.; Lallement, R.; Snowden, Steven L.; Vergely, J.-L.; Snowden, S.

2014-01-01

Three-dimensional (3D) interstellar medium (ISM) maps can be used to locate not only interstellar (IS) clouds, but also IS bubbles between the clouds that are blown by stellar winds and supernovae, and are filled by hot gas. To demonstrate this, and to derive a clearer picture of the local ISM, we compare our recent 3D IS dust distribution maps to the ROSAT diffuse Xray background maps after removal of heliospheric emission. In the Galactic plane, there is a good correspondence between the locations and extents of the mapped nearby cavities and the soft (0.25 keV) background emission distribution, showing that most of these nearby cavities contribute to this soft X-ray emission. Assuming a constant dust to gas ratio and homogeneous 106 K hot gas filling the cavities, we modeled in a simple way the 0.25 keV surface brightness along the Galactic plane as seen from the Sun, taking into account the absorption by the mapped clouds. The data-model comparison favors the existence of hot gas in the solar neighborhood, the so-called Local Bubble (LB). The inferred mean pressure in the local cavities is found to be approx.9,400/cu cm K, in agreement with previous studies, providing a validation test for the method. On the other hand, the model overestimates the emission from the huge cavities located in the third quadrant. Using CaII absorption data, we show that the dust to CaII ratio is very small in those regions, implying the presence of a large quantity of lower temperature (non-X-ray emitting) ionized gas and as a consequence a reduction of the volume filled by hot gas, explaining at least part of the discrepancy. In the meridian plane, the two main brightness enhancements coincide well with the LB's most elongated parts and chimneys connecting the LB to the halo, but no particular nearby cavity is found towards the enhancement in the direction of the bright North Polar Spur (NPS) at high latitude. We searched in the 3D maps for the source regions of the higher energy

Natural gas retailing: writing the last chapter of natural gas deregulation

International Nuclear Information System (INIS)

Bjerkelund, T.

1995-01-01

Under the A greement on Natural Gas Markets and Prices of October 1985, the Canadian federal government agreed to deregulate the price of natural gas and to allow a competitive gas market to develop. Several beneficial changes that have occurred as a result of the deregulation were described, including the Industrial Gas Users Association's (IGUA) view on the marketing and sale of natural gas by local gas distributor's (LDC) and the sale within the LDC franchise. IGUA's support for the separation between LDC distribution and LDC sales and marketing activities as the last step in deregulation process, was explained. Several arguments for the opposing view were also discussed. Recommendations were made for effective separation of LDC distribution and LDC sales/marketing activities

Operation and management of aging gas distribution systems

Energy Technology Data Exchange (ETDEWEB)

McNorgan, J.D. (Southern California Gas Co., Los Angeles, CA (United States))

1993-05-01

Southern California Gas Company, transports billions of cubic feet of natural gas through large-diameter, high-pressure transmission lines, across hundreds of miles of varying terrain, to satisfy the needs of over four and a half million customers. Operating an aging gas system can be truly expensive. Repair costs are very high. Recent figures experienced by our company show that it cost over $800 to repair a main leak, $400 to replace a service, and over $40 a foot to replace even small sized mains. A hidden cost is the effect of the physical limitations imposed by an aging system. It could be under-sized, or limited to a low pressure, thus restricting the volume of gas that can be delivered. Additionally there is the potential loss of valuable gas through leaks or blow downs when making repairs or replacements, and the damage it could do to the environment. For some years Southern California Gas Company has had on-going special and routine pipe replacement programs. The special pipe replacement program is driven primarily to increase the safety of the system, while at the same time improving reliability of service to the customers and reducing their total costs.

The analysis of coolant-velocity distribution in plat-typed fuel element using CFD method for RSG-GAS research reactor

International Nuclear Information System (INIS)

Muhammad Subekti; Darwis Isnaini; Endiah Puji Hastuti

2013-01-01

The measurement experiment for coolant-velocity distribution in the subchannel of fuel element of RSG-GAS research reactor is difficult to be carried out due to too narrow channel and subchannel placed inside the fuel element. Hence, the calculation is required to predict the coolant-velocity distribution inside subchannel to confirm that the handle presence does not ruin the velocity distribution into every subchannel. This calculation utilizes CFD method, which respect to 3-dimension interior. Moreover, the calculation of coolant-velocity distribution inside subchannel was not ever carried out. The research object is to investigate the distribution of coolant-velocity in plat-typed fuel element using 3-dimension CFD method for RSG-GAS research reactor. This research is required as a part of the development of thermalhydraulic design of fuel element for innovative research reactor as well. The modeling uses ½ model in Gambit software and calculation uses turbulence equation in FLUENT 6.3 software. Calculation result of 3D coolant-velocity in subchannel using CFD method is lower about 4.06 % than 1D calculation result due to 1D calculation obeys handle availability. (author)

Distribution of living radiolarians and its response on the environments in spring from the section South China Sea

Science.gov (United States)

Zhang, L.; Hu, W.; Chen, M.; Zeng, L.; Xiang, R.; Zhou, W.

2013-12-01

The composition and spatial (horizontal and vertical) distribution of living radiolarians in spring was firstly studied in the section (18°N and 113°E) South China Sea. Vertical plankton tows were collected at depth-intervals from 0 to 300 m in spring using a closing-type net with 62 um mesh size. And we distinguished the living specimens by staining with Rose Bengal. It dominated by tropical-subtropical warm species in spring from the studied areas. The abundance of nassellarians was the almost same as that of spumellarians in the upper-surface waters (0-25m). In the below-surface waters (25-50m), nassellarian abundance was the almost twice that of spumellarians. And the abundances generally decreased with depth (more than 50m), but nasselarian abundance reduced more quickly. The results showed that the horizontal and vertical distribution patterns of living radiolarians were closely related to the mesoscale eddies. The horizontal distributions of radiolarian abundance were uneven and pachy, which may be related to the complicated mecoscale eddies during the sampling period. That is, there were comparatively high abundances in the upper-surface waters where had the cold eddies development. But in the cold eddies of Meigong River mouth, radiolarian abundance was low due to the large input of fresh water, suggesting that low salinity had more important influence than the nutrient on the radiolarian development and reproduction. Vertically, the highest abundances occurred at the mixed layer in the cold eddies, and gradually decreased with depth. However, in the warm eddies, the maximum abundances were in the thermocline layers, where had an abundant supply of nutrients for radiolarians. This study showed that Didymocyrtis tetrathalamus tetrathalamus mostly occurred at the mixed layer, which should be closely related to the cold eddies and rich nutrition and be limited by the fresh water. Based on the distribution of Didymocyrtis tetrathalamus tetrathalamus, we

Perks of controlled circ: a case study of the distribution practices of Vancouver and Western Living magazines

OpenAIRE

Law, Melanie

2007-01-01

This report examines controlled-circulation magazines using Vancouver and Western Living magazines as successful examples. It provides an analysis of the workings of controlled circulation with reference to advertising, editorial, branding, and operations, and shows how magazines with this distribution method can be successful despite publishing professionals’ common assumption that controlled-circulation magazines are of lesser quality than paid-circulation magazines.

Quality standards proposal for the pipeline gas distribution service in the state of Sao Paulo - Brazil; Proposta de padroes de qualidade para o servico de distribuicao de gas canalizado no Estado de Sao Paulo

Energy Technology Data Exchange (ETDEWEB)

Galvao, Clovis Badaro; Assad, Luiz Sergio [Secretaria de Estado de Energia, Sao Paulo, SP (Brazil); Bajay, Sergio Valdir [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica

1998-12-31

The Energy Supply Public Utilities Commission of the State of Sao Paulo - CSPE created in April 1998 to regulate the public services of electricity and gas distribution through networks in the State. Within its legal attributions, the future staff of CSPE, still in the Sao Paulo Secretary of State of Energy, put forward standards to regulate the quality of service in the distribution of electricity and pipeline gas in the State. This paper summarises the current, still preliminary, version of these gas standards, that take into account the current practice of COMGAS, international, well proven, standards as well as COMGAS capacity to achieve quality of service gains favoring the consumers. (author) 8 refs., 3 tabs.

Effects of post-disposal gas generation in a repository for spent fuel, high-level waste and long-lived intermediate level waste sited in opalinus clay

International Nuclear Information System (INIS)

Johnson, L.; Marschall, P.; Zuidema, P.; Gribi, P.

2004-07-01

This comprehensive report issued by the Swiss National Cooperative for the Disposal of Radioactive Waste NAGRA takes a look at post-disposal gas generation in a repository for spent fuel and highly radioactive wastes in Opalinus clay strata. This study provides a comprehensive treatment of the issue of gas generation in a repository for spent fuel (SF), vitrified high-level waste (HLW) and long-lived intermediate-level waste (ILW), sited in the Opalinus clay of the Zuercher Weinland in northern Switzerland. The issue of how gas generation in and transport from waste repositories may influence disposal system performance has been under study for many years, both at Nagra and internationally. The report consists of three main parts: (i) A synthesis of basic information on the host rock and on details of repository construction; (ii) A discussion on gas transport characteristics of the engineered barrier system and the geosphere; (iii) A discussion on the effects of gas on system performance, based on the available information on gas generation, gas transport properties and gas pathways provided in the previous parts of the report. Simplified model calculations based on a mass balance approach for the gas generated within the repository are presented and discussed

The duration of the transitory period of public gas distribution

International Nuclear Information System (INIS)

Gazzola, D.

2006-01-01

The article describes the interpretative problems concerning the duration of the transitory period of public gas distribution after law decree 273/05 came into effect. This decree is the third legislative measure which, in a period of five years, reforms the transitory provisions. The article outlines the normative background of legislative decree n. 164/00 (so called Letta decree) and law n. 239/04 (so called Marzano law) and it analyses their judicial interpretations. It then explains the changes introduced by law decree n. 273/05 and the new interpretative problems there might be with reference to this decree. The decree clarifies the due date of the transitory period and specifies that the date of 31st December 2005 is postponed to 31st December 2007. The Administrative Tribunal of Lombardia Region Brescia tried to limit the effects of law decree n. 273/05, stating that the new expiration date could not regard the contracts for which the local authorities had already acknowledged the previous due date. The State Council argued instead that the new law decree regards all the contracts. This decree also clarifies that the chances of increasing duration ex art. 15, comma 7, legislative decree n. 164/00, applies automatically, but it doesn't solve the interpretative problem concerning the possibility of adding up more than one of these chances. The article focuses on the problems of the public gas distribution after the reform of this sector with the implementation of directive n. 98/30/CE and it underlines that the various legislative measures of these years are indicative of the difficulty to allow a gradual transition towards a liberalized market. In this context, law decree n. 273/05 is the last legislative measure which tries to guarantee a balance between the rapid liberalization of the market, on one hand, and the interests of the firms which had contracts when the reform came into effect, on the other hand [it

The environmental and socio-economic impacts and benefits associated with developing a natural gas distribution system in Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

Buszynski, M.E.; Peacock, T. [Sempra Atlantic Gas Inc., Halifax, NS (Canada)

2000-07-01

The discovery of large natural gas reserves off the Scotian Shelf has resulted in the development and construction of offshore production platforms as well as underwater and onshore pipelines to transport natural gas to markets on the eastern seaboard. A billion-dollar expenditure is proposed to establish a local distribution company to construct and maintain approximately 8000 km of distribution and lateral pipelines in the province of Nova Scotia. The many aspects of the proposed program were described with particular focus on the regulatory hearings. The paper also discussed the different landscapes that will be crossed and the specialized construction techniques that will be used to meet environmental and economic challenges. The mechanisms in place to ensure maximum benefit for Nova Scotians were also discussed. The proposed project was also compared to other local megaprojects in the province such as the Sable Offshore Energy Project and the Interprovincial Pipeline through Nova Scotia and New Brunswick. Some of the successful strategies for implementing benefits plans related to large energy projects were also described. Sempra has been awarded the franchise to distribute natural gas in Nova Scotia. The company has developed a benefits plan that offers significant local involvement in terms of labour and materials. 4 figs.

BC gas takes new approach to gas supply optimization

International Nuclear Information System (INIS)

Cawdery, J.; Swoveland, C.

1992-01-01

Wide-ranging changes have taken place in the US and Canada since the mid-1980s in the way that local gas distribution utilities and large industrial customers contract for their gas supplies. This paper reports that these changes have been brought about by open-access policies, the intent of which was to allow customers more latitude to make their gas purchase and transportation arrangements and to improve the access of shippers to available gas transmission capacity. The effects of the new open-access regime have been profound on both sides of the border. More than 70% of North American gas supplies are now sold under unbundled arrangements in which gas supply is contracted under separate commodity and transportation agreements. For local distribution utilities, the numbers of potential supply options have become extremely large. Analysis of these options has become increasingly complex with the need to take account of complicated contract provisions, a wider range of storage options and swap arrangements with other utilities, opportunities for some customers to purchase gas directly and uncertainty about future demand, prices and supplier reliability

Distribution of living larger benthic foraminifera in littoral environments of the United Arab Emirates

Science.gov (United States)

Fiorini, Flavia; Lokier, Stephen W.

2015-04-01

The distribution of larger benthic foraminifera in Recent littoral environment of the United Arab Emirates (Abu Dhabi and Western regions) was investigated with the aim of understanding the response of those foraminifera to an increase in water salinity. For this purpose, 100 sediment samples from nearshore shelf, beach-front, channel, lagoon, and intertidal environment were collected. Sampling was undertaken at a water depth shallower than 15 m in water with a temperature of 22 to 35˚C, a salinity ranging from 40 to 60‰ and a pH of 8. Samples were stained with rose Bengal at the moment of sample collection in order to identify living specimens. The most abundant epiphytic larger benthic foraminifera in the studied area were Peneroplis pertusus and P. planatus with less common Spirolina areatina, S. aciculate and Sorites marginalis. The living specimens of the above mentioned species with normal test growing were particularly abundant in the nearshore shelf and lagoonal samples collected on seaweed. Dead specimens were concentrated in the coarser sediments of the beach-front, probably transported from nearby environments. Shallow coastal ponds are located in the upper intertidal zone and have a maximum salinity of 60‰ and contain abundant detached seagrass. Samples collected from these ponds possess a living foraminifera assemblage dominated by Peneroplis pertusus and P. planatus. High percentages (up to 50% of the stained assemblage) of Peneroplis presented abnormality in test growth, such as the presence of multiple apertures with reduced size, deformation in the general shape of the test, irregular suture lines and abnormal coiling. The high percentage of abnormal tests reflects natural environmental stress mainly caused by high and variable salinity. The unique presence of living epiphytic species, suggests that epiphytic foraminifera may be transported into the pond together with seagrass and continued to live in the pond. This hypothesis is supported by

Charge state distribution of ^{86}Kr in hydrogen and helium gas charge strippers at 2.7  MeV/nucleon

Directory of Open Access Journals (Sweden)

H. Kuboki

2014-12-01

Full Text Available The charge state distributions of krypton (^{86}Kr with an energy of 2.7  MeV/nucleon were measured using hydrogen (H_{2} and helium (He gas charge strippers. A differential pumping system was constructed to confine H_{2} and He gases to a thickness sufficient for the charge state distributions to attain equilibrium. The mean charge states of ^{86}Kr in H_{2} and He gases attained equilibrium at 25.1 and 23.2, respectively, whereas the mean charge state in N_{2} gas at equilibrium was estimated to be less than 20. The charge distributions are successfully reproduced by the cross sections of ionization and electron capture processes optimized by a fitting procedure.

Natural gas distribution operation and maintenance dissemination project Kaunas City, Lithuania. Analysis, registration and recommendations on the existing Lithuanian gas measuring practice. Appendix 1

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

It is recommended that the Lithuanian Gas Industry considers: (1) To adopt a base temperature (T{sub b}) of 15 deg. C in order to uniform with the European preferable base temperature [cf. clause. 3.1]. (2) To use TC domestic gas meters at outdoor located gas meters and even when the gas meter is located just inside the exterior wall, in order to avoid too large error on the annual volume measured. Such TC meters should comply with EN 1359 clause B.23 (or alternatively the more strictly Danish type approval requirements) [cf. clause 3.2]. (3) To carry out supplementary high pressure calibration on turbine gas meters intended to be used at operating pressures of 3 or 6 bar in order to check if used makes and types are sensible to Reynolds number. If so, it would result in a measuring error at operating pressures higher than as determined by calibration with air at atmospheric pressure [cf. clause 3.3]. Similar tests should be considered for the existing Vortex gas meters. (4) To adopt the Danish legislation on legal metrology on gas meters in absence of a similar Lithuanian one due to its up to date requirements towards the distribution companies [cf. clause 3.4]. The first step towards such adoption would require a draft translation of the Danish legislation, at least into English. (5) To adopt the Danish in sevice inspection programme on domestic gas meters and on larger gas meters and gas measuring systems as well as on in-situ check of gas-volume electronic conversion devices [cf. clause 3.5.2 - 2.5.4]. The first step towards such adoption would require a draft translation of the 3 existing Danish manuals on calibration and in-situ check programmes, at least into English. Another approach would be a visit at HNG by 2-3 people from the Lithuanian Gas Industry in order to get acquainted with the Danish practice on laboratory calibration and in-situ check of gas-volume electronic conversion devices. However, it should be noticed that in-situ check measuring

By-pass flows and temperature distribution in a hot gas duct internally insulated by carbon stone

International Nuclear Information System (INIS)

Konuk, A.A.

1979-01-01

A mathematical model has been developed to calculate by-pass flows and temperature distribution in a hot gas duct internally insulated by carbon stone rings. The equations of conservation of mass and momentum are solved for a piping system to obtain axial and radial by-pass velocities. The energy equation is solved next by a marching method to obtain the radial temperature distribution along the duct. The results, although qualitative due to simplifications in the model, are useful to study the effects of duct geometry on its performance. (Author) [pt

Modifying the dissolved-in-water type natural gas field simulation model based on the distribution of estimated Young's modulus for the Kujukuri region, Japan

Directory of Open Access Journals (Sweden)

T. Nakagawa

2015-11-01

Full Text Available A simulation model, which covers the part of Southern-Kanto natural gas field in Chiba prefecture, was developed to perform studies and make predictions of land subsidence. However, because large differences between simulated and measured subsidence occurred in the northern modeled area of the gas field, the model was modified with an estimated Young's modulus distribution. This distribution was estimated by the yield value distribution and the correlation of yield value with Young's modulus. Consequently, the simulated subsidence in the north area was improved to some extent.

Network design for cylinder gas distribution

Directory of Open Access Journals (Sweden)

Tejinder Pal Singh

2015-01-01

Full Text Available Purpose: Network design of the supply chain is an important and strategic aspect of logistics management. In this paper, we address the network design problem specific to packaged gases (cylinder supply chain. We propose an integrated framework that allows for the determination of the optimal facility locations, the filling plant production capacities, the inventory at plants and hubs, and the number of packages to be routed in primary and secondary transportation. Design/methodology/approach: We formulate the problem as a mixed integer program and then develop a decomposition approach to solve it. We illustrate the proposed framework with numerical examples from real-life packaged gases supply chain. The results show that the decomposition approach is effective in solving a broad range of problem sizes. Findings: The main finding of this paper is that decomposing the network design problem into two sub-problems is very effective to tackle the real-life large scale network design problems occurring in cylinder gas distribution by optimizing strategic and tactical decisions and approximating the operational decisions. We also benchmark the results from the decomposition approach by solving the complete packaged gases network design model for smaller test cases. Originality/value: The main contribution of our work is that it integrates supply chain network design decisions without fixing the fillings plant locations with inventory and resource allocation decisions required at the plants. We also consider the transportation costs for the entire supply chain including the transhipment costs among different facilities by deciding the replenishment frequency.

Spatial distribution of ion energy related on electron density in a plasma channel generated in gas clusters by a femtosecond laser

International Nuclear Information System (INIS)

Nam, S. M.; Han, J. M.; Cha, Y. H.; Lee, Y. W.; Rhee, Y. J.; Cha, H. K.

2008-01-01

Neutron generation through Coulomb explosion of deuterium contained gas clusters is known as one of the very effective methods to produce fusion neutrons using a table top terawatt laser. The energy of ions produced through Coulomb explosions is very important factor to generate neutrons efficiently. Until the ion energy reaches around∼MeV level, the D D fusion reaction probability increases exponentially. The understanding of laser beam propagation and laser energy deposition in clusters is very important to improve neutron yields. As the laser beam propagates through clusters medium, laser energy is absorbed in clusters by ionization of molecules consisting clusters. When the backing pressure of gas increases, the average size of clusters increases and which results in higher energy absorption and earlier termination of laser propagation. We first installed a Michelson interferometer to view laser beam traces in a cluster plume and to measure spatial electron density profiles of a plasma channel which was produced by a laser beam. And then we measured the energy of ions distributed along the plasma channel with a translating slit to select ions from narrow parts of a plasma channel. In our experiments, methane gas was used to produce gas clusters at a room temperature and the energy distribution of proton ions for different gas backing pressure were measured by the time of flight method using dual micro channel plates. By comparing the distribution of ion energies and electron densities, we could understand the condition for effective laser energy delivery to clusters

THE SMOOTH Mg II GAS DISTRIBUTION THROUGH THE INTERSTELLAR/EXTRA-PLANAR/HALO INTERFACE

International Nuclear Information System (INIS)

Kacprzak, Glenn G.; Cooke, Jeff; Ryan-Weber, Emma V.; Churchill, Christopher W.; Nielsen, Nikole M.

2013-01-01

We report the first measurements of Mg II absorption systems associated with spectroscopically confirmed z ∼ 0.1 star-forming galaxies at projected distances of D r (2796), and impact parameter, D, represented by a single log-linear relation derived by Nielsen et al. (MAGIICAT) that converges to ∼2 Å at D = 0 kpc. Incorporating MAGIICAT, we find that the halo gas covering fraction is unity below D ∼ 25 kpc. We also report that our D r (2796) distributions of the Milky Way interstellar medium (ISM) and ISM+halo. In addition, quasar sight lines of intermediate redshift galaxies with 6 r (2796)-D relation out to large scales across a variety of gas-phase conditions and is maintained through the halo/extra-planar/ISM interfaces, which is remarkable considering their kinematic complexity. These low-redshift, small impact parameter absorption systems are the first steps to bridge the gap between quasar absorption-line studies and H I observations of the circumgalactic medium

Training and certification of the personnel of gas distribution pipe-laying contractor companies in Spain; Formation et certification du personnel des contracteurs pour la pose des gazoducs en Espagne

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

Since the end of the 1980's, the Spanish gas sector has been experiencing a strong rate of growth of consumption, extension of transportation and distribution networks, and numbers of customers, especially in the domestic and commercial market. Polyethylene is playing a primordial rote in the growing extension of distribution networks in Spain, being the material by far the most widely used both in terms of extension of the network and replacement of obsolete materials. For Spanish gas distribution companies, carrying out this extension of the transportation and distribution network is a primordial objective in order to reach and lay gas supplies on to new towns, with the highest levels of quality and safety. This payer describes the personnel certification work on the gas distribution pipe-laying contractor companies carried out by Sedigas within the framework of the requirements of the standard ISO 45013, on certification of personnel. (author)

Emission characteristics and axial flame temperature distribution of producer gas fired premixed burner

Energy Technology Data Exchange (ETDEWEB)

Bhoi, P.R. [Department of Mechanical Engineering, L and T-Sargent and Lundy Limited, L and T Energy Centre, Near Chhani Jakat Naka, Baroda 390 002 (India); Channiwala, S.A. [Department of Mechanical Engineering, Sardar Vallabhbhai National Institute of Technology, Deemed University, Ichchhanath, Surat 395 007, Gujarat (India)

2009-03-15

This paper presents the emission characteristics and axial flame temperature distribution of producer gas fired premixed burner. The producer gas fired premixed burner of 150 kW capacity was tested on open core throat less down draft gasifier system in the present study. A stable and uniform flame was observed with this burner. An instrumented test set up was developed to evaluate the performance of the burner. The conventional bluff body having blockage ratio of 0.65 was used for flame stabilization. With respect to maximum flame temperature, minimum pressure drop and minimum emissions, a swirl angle of 60 seems to be optimal. The experimental results also showed that the NO{sub x} emissions are inversely proportional to swirl angle and CO emissions are independent of swirl angle. The minimum emission levels of CO and NO{sub x} are observed to be 0.167% and 384 ppm respectively at the swirl angle of 45-60 . The experimental results showed that the maximum axial flame temperature distribution was achieved at A/F ratio of 1.0. The adiabatic flame temperature of 1653 C was calculated theoretically at A/F ratio of 1.0. Experimental results are in tune with theoretical results. It was also concluded that the CO and UHC emissions decreases with increasing A/F ratio while NO{sub x} emissions decreases on either side of A/F ratio of 1.0. (author)

Distribution and Kinematics of Ionized Gas in the central 500pc of Seyfert Galaxies

Science.gov (United States)

Hyland, Ella; Hicks, Erin K. S.; Kade, Kiana

2018-06-01

We have characterized the spatial distribution and kinematics of the ionized hydrogen gas in a sample of 40 Seyfert galaxies as part of the KONA (Keck OSIRIS Nearby AGN) survey. An analysis of the narrow Brackett Gamma emission (2.16 microns) in the central 500 pc of these local AGN will be presented. Measurements include the azimuthal averages of the flux distribution, velocity dispersion, and emission line equivalent width. In addition, the excitation of the Brackett Gamma emission is considered using the ratio of its flux with that of molecular hydrogen (2.12 microns) as a diagnostic. A comparison of the circumnuclear narrow Brackett Gamma emission characteristics in the Seyfert type 1 and type 2 subsamples will also be presented.

Frequency and distribution of leakages in steam generators of gas-cooled reactors

International Nuclear Information System (INIS)

Bongratz, R.; Breitbach, G.; Wolters, J.

1988-01-01

In gas cooled reactors with graphitic primary circuit structures - such as HTR, AGR or Magnox - the water ingress is an event of great safety concern. Water or steam entering the primary circuit react with the hot graphite and carbon-oxide and hydrogen are produced. As the most important initiating event a leak in a steam generator must be taken into account. From the safety point of view as well as for availability reasons it is necessary to construct reliable boilers. Thus the occurrence of a boiler leak should be a rare event. In the context of a probabilistic safety study for an HTR-Project much effort was invested to get information about the frequency and the size distribution of tube failures in steam generators of gas cooled reactors. The main data base was the boiler tube failure statistics of United Kingdom gas cooled reactors. The data were selected and applied to a modern HTR steam generator design. A review of the data showed that the failure frequency is not connected with the load level (pressures, temperatures) or with the geometric size of the heating surface of the boiler. Design, construction, fabrication, examination and operation conditions have the greatest influence an the failure frequency but they are practically not to be quantified. The typical leak develops from smallest size. By erosion effects of the entering water or steam it is enlarged to perhaps some mm 2 , then usually it is detected by moisture monitors. Sudden tube breaks were not reported in the investigated period. As a rule boiler leaks in gas cooled reactors are much more, rare then leaks in steam generators of light water reactors and fossil fired boilers. (author)

Localization of fugitive methane emission from natural gas distribution network of Titas Gas

Directory of Open Access Journals (Sweden)

Mandal Pradip C.

2017-03-01

Full Text Available The aim of this paper is to localize the fugitive leaks from the above ground facilities of the existing system of Titas Gas (TG after developing mathematical model for fugitive emission. Soap screening techniques and Gasurveyor 500 series instrument were used in this study for detecting potential leaks. Leaked gas was quantified using either Hi-Flow gas sampler or bagging measurements system. The results show that the respective potential gas leaking point of City Gate Station (CGS, commercial Regulating and Metering Station (RMS, industrial RMS, residential RMS and Town Bordering Station (TBS/ District Regulating Station (DRS are scrubber dump valve (average leak rate 217.00 L/min, insulating point (average leak rate 4.04 L/min, tube fitting connector (average leak rate 8.00 L/min, connector (average leak rate 1.55 L/min and pressure relief valve (average leak rate 437.92 L/min. Fugitive methane emission can be reduced by stopping leaks of fittings or components having high KLeak value.

Power and energy saving in buildings by distributed generation based on gas-engine systems

Energy Technology Data Exchange (ETDEWEB)

Arghandeh, R.; Amidpour, M.; Ghaffari, A. [Khaje Nasir Toosi Univ. of Technology, Tehran (Iran, Islamic Republic of). Joint Program of Energy Systems Engineering; Manchester Univ., Manchester (United Kingdom)

2008-07-01

Buildings consume high amounts of energy and produce high amounts of greenhouse gas (GHG) emissions. This paper discussed the use of gas cogeneration distributed generation (DG) technologies as a means of reducing energy consumption from buildings as well as energy losses from transmission lines in Iran. Energy sources and power generation systems were reviewed, and the economical benefits and energy savings resulting from the use of cogeneration systems were outlined. Actual rates of electricity consumption for Iran were estimated. Building power consumption was divided into the following 6 major sections: (1) lighting, (2) home appliances, (3) restaurant and cooking devices, (4) sports facilities, (5) utilities, and (6) electronics. Energy consumption criteria (ECC) and daily consumption charts (DCC) were used to plan and design the cogeneration systems. Energy balances, capital costs, and investment rates of return (IRR) were then calculated for 2 scenarios for a sample building. Results of the study showed that gas engine combined heat and power (CHP) DG systems are a reliable and economic technology for reducing energy consumption in buildings. The IRR of the CHP DG system for the sample building was achieved in 1 year. 13 refs., 10 tabs., 11 figs.

Integrated biomass gasification combined cycle distributed generation plant with reciprocating gas engine and ORC

International Nuclear Information System (INIS)

Kalina, Jacek

2011-01-01

The paper theoretically investigates the performance of a distributed generation plant made up of gasifier, Internal Combustion Engine (ICE) and Organic Rankine Cycle (ORC) machine as a bottoming unit. The system can be used for maximization of electricity production from biomass in the case where there is no heat demand for cogeneration plant. To analyze the performance of the gasifier a model based on the thermodynamic equilibrium approach is used. Performance of the gas engine is estimated on the basis of the analysis of its theoretical thermodynamic cycle. Three different setups of the plant are being examined. In the first one the ORC module is driven only by the heat recovered from engine exhaust gas and cooling water. Waste heat from a gasifier is used for gasification air preheating. In the second configuration a thermal oil circuit is applied. The oil transfers heat from engine and raw gas cooler into the ORC. In the third configuration it is proposed to apply a double cascade arrangement of the ORC unit with a two-stage low temperature evaporation of working fluid. This novel approach allows utilization of the total waste heat from the low temperature engine cooling circuit. Two gas engines of different characteristics are taken into account. The results obtained were compared in terms of electric energy generation efficiency of the system. The lowest obtained value of the efficiency was 23.6% while the highest one was 28.3%. These are very favorable values in comparison with other existing small and medium scale biomass-fuelled power generation plants. - Highlights: →The study presents performance analysis of a biomass-fuelled local power plant. →Downdraft wood gasifier, gas engine and ORC module are modelled theoretically. →Method for estimation of the producer gas fired engine performance is proposed. →Two gas engines of different characteristics are taken into account. →Different arrangements of the bottoming ORC cycle ere examined.

A comparison of cost-based pricing rules for natural gas distribution utilities

International Nuclear Information System (INIS)

Klein, C.C.

1993-01-01

Partial-equilibrium social welfare deadweight losses under uniform Ramsey pricing, a cost allocation pricing method, and the actual average revenues by customer class for two natural gas distribution utilities are calculated and compared. Marginal cost estimates are derived from a multiple-output translog variable cost function and used, along with three sets of demand elasticities, to generate the Ramsey prices and welfare losses. The actual and cost-allocation prices are taken directly from rate case files. The largest social welfare losses are associated with the cost-allocation rule, as high as 10-25% of revenue, despite suggestions in the literature to the contrary. (Author)

Policy subjects of the LP gas industry; LP gas sangyo no seisaku kadai

Energy Technology Data Exchange (ETDEWEB)

Murata, K. [Agency of Natural Resources and Energy, Tokyo (Japan)

1996-09-01

The paper commented on current environmental changes in the LP gas industry and the measures for reinforcement of the physical constitution. When correction of the high cost structure in Japan is now the problem, waves of deregulation and rationalization reach to not only to LP gas but energy competitive with LP gas such as petroleum, electric power and town gas. With this, it is expected that LP gas will be faced with severe competition with other energy media. In the LP gas industry, business becomes more and more in number and smaller and smaller in scale as it extends downstream. Therefore, the resulting complicatedness in the distribution sector is the problem. It is necessary to realize scale profit in each distribution stage and to heighten productivity by expanding the scale in the retailing stage, especially. It is also important to tackle scale merit, improvement of productivity, and cost reduction by concentrating functions on either of wholesalers or retailers in every function of delivery, safety, free from each distribution stage.

Risk management system in the natural gas distribution of Lima and Callao according guidelines “Recommendations on transmission and distribution practice” and risk management of the PMI Project (2008)

OpenAIRE

Luján Ruiz, Roger Orlando

2014-01-01

The purpose of this research study is to analyze quantitative operational risk according to the guidelines of the practice recommendation “Recommendations on Transmission and Distribution Practice” , published by The Institution of Gas Engineers of Great Britain and the PMBOK . Chapter 11 , Managing Project Risk . This study was conducted in the Trunk pipeline system operated by Cálidda the Peru - Natural Gas from the City Gate located in Lurín , to Callao Terminal Station . The purpose of th...

Distribution of heavy metals from flue gas in algal bioreactor

Science.gov (United States)

Napan, Katerine

Flue gas from coal-fired power plants is a major source of CO2 to the atmosphere. Microalgae can use this enriched form of CO2 as carbon source and in turn the biomass can be used to produce food, feed, fertilizer and biofuels. However, along with CO2, coal-based flue gas will inevitably introduce heavy metals, which have a high affinity to bind algal cells, could be toxic to the organisms and if transferred to the products could limit their uses. This study seeks to address the distribution and impact of heavy metals present in flue gas on microalgae production systems. To comprehend its effects, algae Scenedesmus obliquus was grown in batch reactors in a multimetal system. Ten heavy metals (Cu, Co, Zn, Pb, As, Se, Cr, Hg, Ni and Cd) were selected and were evaluated at four concentrations (1X, 2X, 5X and 10X). Results show that most heavy metals accumulated mainly in biomass and were found in very low concentrations in media. Hg was shown to be lost from the culture, with low amounts present in the biomass. An upper limit for As uptake was observed, suggesting its likelihood to build-up in the system during medium recycle. The As limited bioaccumulation was overcome by addition of sulfur to the algal medium. Heavy metal at 2X, 5X and 10X inhibited both growth and lipid production, while at the reference concentration both biomass and lipids yields were increased. Heavy metal concentrations in the medium and biomass were time dependent, and at the end of the cultivation most heavy metals in the supernatant solution complied with the recommendations for irrigation water, while biomass was below limits for cattle and poultry feed, fertilizer, plastic and paper. This research shows that bioremediation of CO2 and heavy metals in combination with energy production can be integrated, which is an environmentally friendly form of biotechnology.

An overview of the political, technical and economical aspects of gas-fired distributed energy system in China

International Nuclear Information System (INIS)

Chen, Qiaohui; Wang, Weilong; Lu, Jianfeng; Ding, Jing

2013-01-01

The interest in distributed energy system has been increasing in China in recent years due to the environmental and energy policy concerns. The distributed energy system generates power, heating and cooling to residential, commercial and industrial facilities. Due to cascade utilization of energy, it can make good use of energy to improve energy efficiency and to increase energy savings. Furthermore, it consumes less energy and reduces carbon emissions. This paper reviews existing and newly-built gas-fired distributed energy projects in China. The techno-economic assessment of the selected projects has also been discussed and reported. The results show that in Xiamen Jimei DE project, the primary energy ratio of the DES can be as high as 92.9%, and energy-saving rate is 35.5%. Moreover, exergy efficiency reaches 54.3%, and the system can reduce 0.52 million tons of CO 2 annually. -- Highlights: ► The political, technical and economical aspects of gas-fired DES are analyzed. ► The techno-economic assessment of two selected projects is conducted. ► Primary energy ratio can be as high as 92.9% and energy-saving rate is 35.5%. ► Exergy efficiency is 54.3% and the system can reduce a large amount of CO 2 emissions

Modeling of the evolution of bubble size distribution of gas-liquid flow inside a large vertical pipe. Influence of bubble coalescence and breakup models

International Nuclear Information System (INIS)

Liao, Yixiang; Lucas, Dirk

2011-01-01

The range of gas-liquid flow applications in today's technology is immensely wide. Important examples can be found in chemical reactors, boiling and condensation equipments as well as nuclear reactors. In gas-liquid flows, the bubble size distribution plays an important role in the phase structure and interfacial exchange behaviors. It is therefore necessary to take into account the dynamic change of the bubble size distribution to get good predictions in CFD. An efficient 1D Multi-Bubble-Size-Class Test Solver was introduced in Lucas et al. (2001) for the simulation of the development of the flow structure along a vertical pipe. The model considers a large number of bubble classes. It solves the radial profiles of liquid and gas velocities, bubble-size class resolved gas fraction profiles as well as turbulence parameters on basis of the bubble size distribution present at the given axial position. The evolution of the flow along the height is assumed to be solely caused by the progress of bubble coalescence and break-up resulting in a bubble size distribution changing in the axial direction. In this model, the bubble coalescence and breakup models are very important for reasonable predictions of the bubble size distribution. Many bubble coalescence and breakup models have been proposed in the literature. However, some obvious discrepancies exist in the models; for example, the daughter bubble size distributions are greatly different from different bubble breakup models, as reviewed in our previous publication (Liao and Lucas, 2009a; 2010). Therefore, it is necessary to compare and evaluate typical bubble coalescence and breakup models that have been commonly used in the literature. Thus, this work is aimed to make a comparison of several typical bubble coalescence and breakup models and to discuss in detail the ability of the Test Solver to predict the evolution of bubble size distribution. (orig.)

Green gas. Gas of natural gas quality from biomass. Update of the 2004 study

International Nuclear Information System (INIS)

Welink, Jan-Henk; Dumont, M.; Kwant, K.

2007-01-01

In 2004 a study was published on green gas. Green gas is defined as a gaseous energy carrier from renewable biomass with a similar quality as natural gas. As a result of new developments in the field of co-digestion/fermentation the Dutch Ministry of Economic Affairs asked it's agency SenterNovem to update the 2004 study. The aim of the update is (1) to gain insight into operational aspects of green gas projects, e.g. reliability, efficiency and maintenance aspects; (2) stimulate the production of green gas, taking into account the economics of green gas projects, calculation of the financial gap of green gas production, efficient use of biogas (conversion to electricity or directly input into the natural gas distribution systems, and aspects with regard to commercialization and the market; and (3) the potential of green gas [nl

Effects of gas liquid ratio on the atomization characteristics of gas-liquid swirl coaxial injectors

Science.gov (United States)

Kang, Zhongtao; Li, Qinglian; Zhang, Jiaqi; Cheng, Peng

2018-05-01

To understand the atomization characteristics and atomization mechanism of the gas-liquid swirl coaxial (GLSC) injector, a back-lighting photography technique has been employed to capture the instantaneous spray images with a high speed camera. The diameter and velocity of the droplets in the spray have been characterized with a Dantec Phase Doppler Anemometry (PDA) system. The effects of gas liquid ratio (GLR) on the spray pattern, Sauter mean diameter (SMD), diameter-velocity distribution and mass flow rate distribution were analyzed and discussed. The results show that the atomization of the GLSC injector is dominated by the film breakup when the GLR is small, and violent gas-liquid interaction when the GLR is large enough. The film breakup dominated spray can be divided into gas acceleration region and film breakup region while the violent gas-liquid interaction dominated spray can be divided into the gas acceleration region, violent gas-liquid interaction region and big droplets breakup region. The atomization characteristics of the GLSC injector is significantly influenced by the GLR. From the point of atomization performance, the increase of GLR has positive effects. It decreases the global Sauter mean diameter (GSMD) and varies the SMD distribution from a hollow cone shape (GLR = 0) to an inverted V shape, and finally slanted N shape. However, from the point of spatial distribution, the increase of GLR has negative effects, because the mass flow rate distribution becomes more nonuniform.

Natural gas monthly

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-01-01

The Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the Natural Gas Monthly features articles designed to assist readers in using and interpreting natural gas information.

A survey of financing possibilities of projects in energetics with emphasis to the market with natural gas

Directory of Open Access Journals (Sweden)

Abed Al-Zabidi

2009-09-01

Full Text Available With the present expansion of globalization within economic competition of individual countries are stability and economicdevelopment inevitably bound with the term of energy, therefore also the natural gas. Presently, energy is still the most important factorof economic and social development.The critical tempo of energy consumption, entering of new players on the energetic market, quick industrialization of Asiancountries and accordingly growing difference between supply and demand, worries of depletion of the existing sources and worseningof our living environment are all worldwide global problems.The subject of the presented paper is a survey of market with natural gas in Slovakia, possibilities of diversification of sourcesof natural gas, its transport and distribution with the emphasis to the possibilities of financing of projects in energetics.

Multi-gas interaction modeling on decorated semiconductor interfaces: A novel Fermi distribution-based response isotherm and the inverse hard/soft acid/base concept

Energy Technology Data Exchange (ETDEWEB)

Laminack, William [Department of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Gole, James, E-mail: James.Gole@physics.gatech.edu [Department of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Department of Mechanical Engineering, Georgia Tech, Atlanta, GA 30332 (United States)

2015-12-30

Graphical abstract: Visual representation of the PS interface interacting with mixed gas configurations. The red dots correspond to nanostructured metal oxides. Each combination of distinct molecules are labeled below the pores, which are oversized in the figure. - Highlights: • First study of mixed gas analytes interacting with a micro-porous silicon substrate. • Responses are represented by a newly developed response absorption isotherm. • This isotherm is modeled on the basis of the Fermi distribution function. • The developing IHSAB concept explains multi-gas analyte–analyte interactions. - Abstract: A unique MEMS/NEMS approach is presented for the modeling of a detection platform for mixed gas interactions. Mixed gas analytes interact with nanostructured decorating metal oxide island sites supported on a microporous silicon substrate. The Inverse Hard/Soft acid/base (IHSAB) concept is used to assess a diversity of conductometric responses for mixed gas interactions as a function of these nanostructured metal oxides. The analyte conductometric responses are well represented using a combination diffusion/absorption-based model for multi-gas interactions where a newly developed response absorption isotherm, based on the Fermi distribution function is applied. A further coupling of this model with the IHSAB concept describes the considerations in modeling of multi-gas mixed analyte–interface, and analyte–analyte interactions. Taking into account the molecular electronic interaction of both the analytes with each other and an extrinsic semiconductor interface we demonstrate how the presence of one gas can enhance or diminish the reversible interaction of a second gas with the extrinsic semiconductor interface. These concepts demonstrate important considerations in the array-based formats for multi-gas sensing and its applications.

Natural gas for New Brunswick: First report

International Nuclear Information System (INIS)

1998-01-01

The development of the gas field off Sable Island and the imminent construction of a gas pipeline which will deliver natural gas to New Brunswick has prompted a thorough examination of energy-related issues in the province. This report presents the findings of the provincial energy committee which examined the implications of the arrival of natural gas to the province. The committee held a series of public hearings and consultations, and also received written submissions. After a historical perspective on natural gas as an energy source in the province and a review of the gas industry participants and their interests, the report discusses such issues as gas pipeline economics, local distribution company operations, infrastructure development, the regulatory framework, energy market competition, regional price equity, development of in-province gas sources, pipeline access, pipeline laterals and expansions, establishment of gas distribution franchises, municipal involvement in gas development, the impact of gas industry development on electric utility restructuring, and the environmental benefits of natural gas. Finally, recommendations are made regarding how natural gas should be regulated and distributed

Prevalence and distribution of cervical high-risk human papillomavirus and cytological abnormalities in women living with HIV in Denmark - the SHADE

DEFF Research Database (Denmark)

Thorsteinsson, Kristina; Storgaard, Merete; Katzenstein, Terese L

2016-01-01

BACKGROUND: Women living with HIV (WLWH) are at increased risk of persistent human papillomavirus (HPV) infection, cervical dysplasia and cervical cancer compared with women from the general population (WGP). We assessed the prevalence and distribution of cervical high-risk (hr) HPV infection and...

Technical change and efficiency measures. The post-privatisation in the gas distribution sector in Argentina

International Nuclear Information System (INIS)

Rossi, M.A.

2001-01-01

In this paper we use a stochastic frontier approach to analyse the technical change in the post-privatisation period in the gas distribution sector in Argentina. We found that there is both a catching up effect and a shift in the frontier, which shows that the sector as a whole improved its efficiency in the reviewed period. Moreover, this phenomenon holds not only for the average but also for every firm in the sample

The legal basis of natural gas distribution technology. 2. rev. ed.

International Nuclear Information System (INIS)

Ambos, G.; Bramkamp, F.B.; Rienen, W. van

1993-01-01

The body of legal regulations reaches from general power economy laws to technical safety and environmental laws as well as to laws on construction regulations. The legal regulations laid down by the European Community in regard to the creation of a European single market are of increasing significance. The book wants to give basic information on the relevant legal areas and makes it easier to understand the structure and the systematics of the laws on power supply technology. It does so by differentiating three areas: - Survey of the legal regulatory framework: - Depiction of the basis of energy laws and the questions which arise from the practical work of the energy control board: - Survey of the technical safety and emission control laws in regard to natural-gas distribution by public utilities. (orig.) [de

Reconstruction of Low Pressure Gas Supply System

Directory of Open Access Journals (Sweden)

S. N. Osipov

2013-01-01

Full Text Available The current reconstruction of residential areas in large cities especially with the developed heat-supply systems from thermal power stations and reduction of heat consumption for heating due to higher thermal resistance of building enclosing structures requires new technical solutions in respect of gas-supply problems. While making reconstruction of a gas-supply system of the modernized or new buildings in the operating zone of one gas-distribution plant it is necessary to change hot water-supply systems from gas direct-flow water heaters to centralized heat-supply and free gas volumes are to be used for other needs or gas-supply of new buildings with the current external gas distribution network.Selection of additional gas-line sections and points of gas-supply systems pertaining to new and reconstructed buildings for their connection to the current distribution system of gas-supply is to be executed in accordance with the presented methodology.

Integrated resource planning for local gas distribution companies: A critical review of regulatory policy issues

International Nuclear Information System (INIS)

Harunuzzaman, M.; Islam, M.

1994-08-01

According to the report, public utility commissions (PUCs) are increasingly adopting, or considering the adoption of integrated resource planning (IRP) for local gas distribution companies (LDCs). The Energy Policy Act of 1992 (EPAct) requires PUCs to consider IRP for gas LDCs. This study has two major objectives: (1) to help PUCs develop appropriate regulatory approaches with regard to IRP for gas LDCs; and (2) to help PUCs respond to the EPAct directive. The study finds that it is appropriate for PUCs to pursue energy efficiency within the traditional regulatory framework of minimizing private costs of energy production and delivery; and PUCs should play a limited role in addressing environmental externalities. The study also finds that in promoting energy efficiency, PUCs should pursue policies that are incentive-based, procompetitive, and sensitive to rate impacts. The study evaluates a number of traditional and nontraditional ratemaking mechanisms on the basis of cost minimization, energy efficiency, competitiveness, and other criteria. The mechanisms evaluated include direct recovery of DSM expenses, lost revenue adjustments for DSM options, revenue decoupling mechanisms, sharing of DSM cost savings, performance-based rate of return for DSM, provision of DSM as a separate service, deregulation of DSM service, price caps, and deregulation of the noncore gas market. The study concludes with general recommendations for regulatory approaches and ratemaking mechanisms that PUCs may wish to consider in advancing IRP objectives

Dust and gas distribution in molecular clouds: an observational approach

International Nuclear Information System (INIS)

Campeggio, Loretta; Elia, Davide; Maiolo, Berlinda M T; Strafella, Francesco; Cecchi-Pestellini, Cesare

2005-01-01

The interstellar medium (ISM), gas and dust, appears to be arranged in clouds, whose dimensions, masses and densities span a large range of scales: from giant molecular clouds to small isolated globules. The structure of these objects show a high degree of complexity appearing, in the range of the observed scales, as a non-homogeneous ('clumpy') distribution of matter. The arrangement of the ISM is clearly relevant for the study of the fragmentation of the clouds and then of the star formation processes. To quantify observationally the ISM structure, many methods have been developed and our study is focused on some of them, exploiting multiwavelength observations of IS objects. The investigations presented here have been carried out by considering both the dust absorption (in optical and near IR wavelengths) and the gas emission (in the submm-radio spectral range). We present the maps obtained from the reduction of raw data and a first tentative analysis by means of methods as the structure function, the autocorrelation, and the Δ-variance. These are appropriate tools to highlight the complex structure of the ISM with reference to the paradigm given by the supersonic turbulence. Three observational cases are briefly discussed. In order to analyse the structure of objects characterized by different sizes, we applied the above-mentioned algorithms to the extinction map of the dark globule CB 107 and to the CO(J = 1-0) integrated intensity map of Vela Molecular Ridge, D Cloud. Finally we compare the results obtained with synthetic fractal maps known as 'fractional Brownian motion' fBm images

Direct observation of two dimensional trace gas distributions with an airborne Imaging DOAS instrument

Directory of Open Access Journals (Sweden)

K.-P. Heue

2008-11-01

Full Text Available In many investigations of tropospheric chemistry information about the two dimensional distribution of trace gases on a small scale (e.g. tens to hundreds of metres is highly desirable. An airborne instrument based on imaging Differential Optical Absorption Spectroscopy has been built to map the two dimensional distribution of a series of relevant trace gases including NO₂, HCHO, C₂H₂O₂, H₂O, O₄, SO₂, and BrO on a scale of 100 m.

Here we report on the first tests of the novel aircraft instrument over the industrialised South African Highveld, where large variations in NO₂ column densities in the immediate vicinity of several sources e.g. power plants or steel works, were measured. The observed patterns in the trace gas distribution are interpreted with respect to flux estimates, and it is seen that the fine resolution of the measurements allows separate sources in close proximity to one another to be distinguished.

Gas industry construction expenditures to grow rapidly

International Nuclear Information System (INIS)

Quarles, W.R.

1991-01-01

Between 1991 and 1993, the natural gas industry will invest $28.297 billion to install additional facilities for natural gas production and storage, transmission, underground storage, gas distribution and for other general expenditures, estimates the American Gas Association as shown in the 1990 Gas Facts. This is a 38% investment increase from the forecasts in the 1989 Gas Facts. This issue forecasts investments of $13.303 billion for 1991 and $18.396 billion for 1992. This issue does not include investments for 1993. In 1989, (the last figures released) the gas industry invested $7,341 billion for new transmission lines, distribution mains, underground storage, production and storage and general facilities. Included in the 1989 expenditures are: $3.980 billion in distribution facilities; $2.081 billion in gas transmission systems and $159 million in underground storage facilities. Investment in new distribution facilities in 1991 and $4.550 billion in 1993. This is a steady increase for these three years. Investments in natural gas transmission facilities show a steady increase also. In 1991, pipe line operating companies will invest $9.391 billion for new facilities, $9.005 in 1992 and $9.901 billion in 1993

Equivalent formation strength as a proxy tool for exploring the existence and distribution of gas hydrates

Science.gov (United States)

Hamada, Y.; Yamada, Y.; Sanada, Y.; Nakamura, Y.; Kido, Y. N.; Moe, K.

2017-12-01

Gas hydrates bearing layer can be normally identified by a basement simulating reflector (BSR) or well logging because of their high acoustic- and electric impedance compared to the surrounding formation. These characteristics of the gas hydrate can also represent contrast of in-situ formation strength. We here attempt to describe gas hydrate bearing layers based on the equivalent strength (EST). The Indian National Gas Hydrate Program (NGHP) Expedition 02 was executed 2015 off the eastern margin of the Indian Peninsula to investigate distribution and occurrence of gas hydrates. From 25 drill sites, downhole logging data, cored samples, and drilling performance data were collected. Recorded drilling performance data was converted to the EST, which is a developed mechanical strength calculated only by drilling parameters (top drive torque, rotation per minute , rate of penetration , and drill bit diameter). At a representative site, site 23, the EST shows constant trend of 5 to 10 MPa, with some positive peaks at 0 - 270 mbsf interval, and sudden increase up to 50 MPa above BSR depth (270 - 290 mbsf). Below the BSR, the EST stays at 5-10 MPa down to the bottom of the hole (378 mbsf). Comparison of the EST with logging data and core sample description suggests that the depth profiles of the EST reflect formation lithology and gas hydrate content: the EST increase in the sand-rich layer and the gas hydrate bearing zone. Especially in the gas hydrate zone, the EST curve indicates approximately the same trend with that of P-wave velocity and resistivity measured by downhole logging. Cross plot of the increment of the EST and resistivity revealed the relation between them is roughly logarithmic, indicating the increase and decrease of the EST strongly depend on the saturation factor of gas hydrate. These results suggest that the EST, proxy of in-situ formation strength, can be an indicator of existence and amount of the gas-hydrate layer. Although the EST was calculated

The Spanish gas industry

International Nuclear Information System (INIS)

Anon.

1993-01-01

The spanish gas industry has become one of the major actors in the gas sector of the European Economic Community. This paper pictures the spanish gas industry on the basis of a study by Sedigas, the spanish member of the International Gas Union (IGU). The main subjects described are structure of gas companies, natural gas supply, transport and storage, natural gas distribution networks, statistical data on natural gas consumption, manufactured gas and Liquefied Petroleum Gases (LPG) production-consumption in Spain. 7 figs., 10 tabs

Distributed Energy Generation Systems Based on Renewable Energy and Natural Gas Blending: New Business Models for Economic Incentives, Electricity Market Design and Regulatory Innovation

Science.gov (United States)

Nyangon, Joseph

Expansion of distributed energy resources (DERs) including solar photovoltaics, small- and medium-sized wind farms, gas-fired distributed generation, demand-side management, and energy storage poses significant complications to the design, operation, business model, and regulation of electricity systems. Using statistical regression analysis, this dissertation assesses if increased use of natural gas results in reduced renewable energy capacity, and if natural gas growth is correlated with increased or decreased non-fossil renewable fuels demand. System Generalized Method of Moments (System GMM) estimation of the dynamic relationship was performed on the indicators in the econometric model for the ten states with the fastest growth in solar generation capacity in the U.S. (e.g., California, North Carolina, Arizona, Nevada, New Jersey, Utah, Massachusetts, Georgia, Texas, and New York) to analyze the effect of natural gas on renewable energy diffusion and the ratio of fossil fuels increase for the period 2001-2016 to policy driven solar demand. The study identified ten major drivers of change in electricity systems, including growth in distributed energy generation systems such as intermittent renewable electricity and gas-fired distributed generation; flat to declining electricity demand growth; aging electricity infrastructure and investment gaps; proliferation of affordable information and communications technologies (e.g., advanced meters or interval meters), increasing innovations in data and system optimization; and greater customer engagement. In this ongoing electric power sector transformation, natural gas and fast-flexing renewable resources (mostly solar and wind energy) complement each other in several sectors of the economy. The dissertation concludes that natural gas has a positive impact on solar and wind energy development: a 1% rise in natural gas capacity produces 0.0304% increase in the share of renewable energy in the short-run (monthly) compared

Influence of forced internal air circulation on airflow distribution and heat transfer in a gas double-dynamic solid-state fermentation bioreactor.

Science.gov (United States)

Chen, Hongzhang; Qin, Lanzhi; Li, Hongqiang

2014-02-01

Internal air circulation affects the temperature field distribution in a gas double-dynamic solid-state fermentation bioreactor (GDSFB). To enhance heat transfer through strengthening internal air circulation in a GDSFB, we put an air distribution plate (ADP) into the bioreactor and studied the effects of forced internal air circulation on airflow, heat transfer, and cellulase activity of Trichoderma viride L3. Results showed that ADP could help form a steady and uniform airflow distribution, and with gas-guide tubes, air reversal was formed inside the bioreactor, thus resulting in a smaller temperature difference between medium and air by enhancing convective heat transfer inside the bioreactor. Using an ADP of 5.35 % aperture ratio caused a 1 °C decrease in the average temperature difference during the solid-state fermentation process of T. viride L3. Meanwhile, the cellulase activity of T. viride L3 increased by 13.5 %. The best heat-transfer effect was attained when using an ADP of 5.35 % aperture ratio and setting the fan power to 125 V (4.81 W) in the gas double-dynamic solid-state fermentation (GDSF) process. An option of suitable aperture ratio and fan power may be conducive to ADPs' industrial amplification.

Assessing the safety aspects for use of multilayer pipes in gas distribution of domestic installation; Avaliacao dos aspectos de seguranca para utilizacao de tubos multicamada em instalacoes de distribuicao de gas em residencias

Energy Technology Data Exchange (ETDEWEB)

Bratfisch, Carlos do Amaral Coutinho [Bratfisch - Engenharia em Gas, Sao Paulo, SP (Brazil); Emmeti, Sao Paulo, SP (Brazil); Collela, Ricardo [FGS Brasil Industria e Comercio Ltda., Cotia, SP (Brazil)

2012-07-01

The gas distribution networks average flow at the Brazilian market is low and the operating pressure is less than 2.0 kgf/cm{sup 2}. These values are lower if compared to other countries and due this, gas distribution companies, major builders and developers have started a movement to find alternatives to reduce their installation costs, and they have identified in other countries the multilayer system. Because of the great interest of the consumer market for this alternative, and since there is no standards in Brazil that could regulate it, a technical committee was established under the ABNT in order to prepare a standard draft meeting the local market particularities as well this technology requirements. Then it was initiated a quest looking for the knowledge of the 'state of the art' of this technology in various locations around the world, especially Europe, Asia and Oceania, which shows that, with few exceptions, the knowledge of this alternative is still on the beginning, and even in countries where this system is a pioneer some doubts exist with respect to their usage limit. The multilayer system materials were already used at hot and cold water networks for more than twelve years, but only after that it was made an adaptation for building installations of gas distribution networks. Due the need to search and establish safety criteria both with respect to the product as its installation shape, did the necessary motivation to perform a more detailed study of this new technology, meeting the needs of this market. The intention is to present to the consumer market a series of comparative data definitions and techniques to identify this as a modern, updated, economic, efficient and safe alternative option for gas distribution networks. (author)

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.)

A Robust Distributed Multipoint Fiber Optic Gas Sensor System Based on AGC Amplifier Structure.

Science.gov (United States)

Zhu, Cunguang; Wang, Rende; Tao, Xuechen; Wang, Guangwei; Wang, Pengpeng

2016-07-28

A harsh environment-oriented distributed multipoint fiber optic gas sensor system realized by automatic gain control (AGC) technology is proposed. To improve the photoelectric signal reliability, the electronic variable gain can be modified in real time by an AGC closed-loop feedback structure to compensate for optical transmission loss which is caused by the fiber bend loss or other reasons. The deviation of the system based on AGC structure is below 4.02% when photoelectric signal decays due to fiber bending loss for bending radius of 5 mm, which is 20 times lower than the ordinary differential system. In addition, the AGC circuit with the same electric parameters can keep the baseline intensity of signals in different channels of the distributed multipoint sensor system at the same level. This avoids repetitive calibrations and streamlines the installation process.

Software for the decision making support on the design of natural gas distribution networks; Software de apoio a decisao para o projeto de rede urbanas de distribuicao de gas natural

Energy Technology Data Exchange (ETDEWEB)

Goldbarg, Marco C.; Goldbarg, Elizabeth F.G. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Campos, Michel F. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2004-07-01

This work presents a computational system to aid the decision making process of installing new networks to distribute natural gas in an urban area. The system is called POM-DIGAS. The purpose of the software is to optimize the design of natural gas distribution networks. The general optimization problem comprises two combinatorial problems. The first one refers to the definition of the network layout. In this problem the objective is to minimize the total length of the network. The second combinatorial problem considers the pipe size optimization in which one must choose the diameters of the pipes regarding the demand requirements. POM-DIGAS is a composite of models and algorithms developed to tackle the two combinatorial problems. Furthermore, the software has a geographic information mode, a tool to automatically acquire several types of data concerning the project and a mode with distinct flow equations in order to allow the utilization of different methodologies for computing the network flows. The system was applied to a case study developed for the city of Natal, Rio Grande do Norte. This work was supported by RedeGasEnergia, FINEP and PETROBRAS. (author)

Life-cycle greenhouse gas emissions of shale gas, natural gas, coal, and petroleum.

Science.gov (United States)

Burnham, Andrew; Han, Jeongwoo; Clark, Corrie E; Wang, Michael; Dunn, Jennifer B; Palou-Rivera, Ignasi

2012-01-17

The technologies and practices that have enabled the recent boom in shale gas production have also brought attention to the environmental impacts of its use. It has been debated whether the fugitive methane emissions during natural gas production and transmission outweigh the lower carbon dioxide emissions during combustion when compared to coal and petroleum. Using the current state of knowledge of methane emissions from shale gas, conventional natural gas, coal, and petroleum, we estimated up-to-date life-cycle greenhouse gas emissions. In addition, we developed distribution functions for key parameters in each pathway to examine uncertainty and identify data gaps such as methane emissions from shale gas well completions and conventional natural gas liquid unloadings that need to be further addressed. Our base case results show that shale gas life-cycle emissions are 6% lower than conventional natural gas, 23% lower than gasoline, and 33% lower than coal. However, the range in values for shale and conventional gas overlap, so there is a statistical uncertainty whether shale gas emissions are indeed lower than conventional gas. Moreover, this life-cycle analysis, among other work in this area, provides insight on critical stages that the natural gas industry and government agencies can work together on to reduce the greenhouse gas footprint of natural gas.

Development of Slovenian natural gas distribution for future integration and competition; Developpement du reseau de distribution du gaz Slovene en vue de l'integration et de la concurrence futures

Energy Technology Data Exchange (ETDEWEB)

Cimerman, F.; Polpis-Perpar, B. [Javno podjetje Energetika Ljubljana (Slovenia)

2000-07-01

The European gas industry is currently facing increased competition in the end consumer market. Therefore, many European countries have begun to transform their gas industries to assure a better position in the competitive environment. The impact of these developments will probably go beyond the national gas market. Harmonization and cost reduction will clearly become even more important determinants than they have been in the past for whole national gas supply chain. New developments in the European gas market, an awareness of our position on the Slovenian natural gas market and our plan to join the European Community have forced us to adopt European regulations and introduce cost reductions in several natural gas activities. Our main goal is to be prepared with regard to regulation and to employ cost management to reduce costs in order to offer a better natural gas price for our end consumers. Our paper is separated in two parts. The first part introduces the current situation with regard to the harmonization of our regulations with European directives. The second part presents our preparation for changes in the gas market in terms of cost reduction. In this paper we will try to present the initial steps which the largest Slovenian natural gas distribution company is taking to deal with future incorporation and competition. (authors)

Control of temperature distribution in a supercritical gas extraction tower

International Nuclear Information System (INIS)

Yoshida, M.; Matsumoto, S.; Honda, G.; Iwama, T.; Suzuki, Y.; Odagiri, S.

1989-01-01

A control scheme recently proposed by the authors is applied to the control of axial temperature distribution in a bench-scale supercritical-gas extractor. The extraction unit is constructed from a packed column 3 m long covered by a coaxial cylindrical casing. Although the actual structure of the extractor is very complicated, it is modeled by a simple double-pipe and therefore its mathematical model can be described by a pair of partial differential equations. The models are reduced to a lumped parameter system with a finite dimension by use of the finite Fourier transform technique. The controller is designed on the basis of the reduced model. An extended Kalman filter is used to estimate simultaneously the state variables and the unknown parameters. The results demonstrate that both the state estimation and the controller performance are satisfactory. This implies that the control scheme is very robust in spite of the incompleteness of the model used

Effect of Coulomb friction on orientational correlation and velocity distribution functions in a sheared dilute granular gas.

Science.gov (United States)

Gayen, Bishakhdatta; Alam, Meheboob

2011-08-01

From particle simulations of a sheared frictional granular gas, we show that the Coulomb friction can have dramatic effects on orientational correlation as well as on both the translational and angular velocity distribution functions even in the Boltzmann (dilute) limit. The dependence of orientational correlation on friction coefficient (μ) is found to be nonmonotonic, and the Coulomb friction plays a dual role of enhancing or diminishing the orientational correlation, depending on the value of the tangential restitution coefficient (which characterizes the roughness of particles). From the sticking limit (i.e., with no sliding contact) of rough particles, decreasing the Coulomb friction is found to reduce the density and spatial velocity correlations which, together with diminished orientational correlation for small enough μ, are responsible for the transition from non-gaussian to gaussian distribution functions in the double limit of small friction (μ→0) and nearly elastic particles (e→1). This double limit in fact corresponds to perfectly smooth particles, and hence the maxwellian (gaussian) is indeed a solution of the Boltzmann equation for a frictional granular gas in the limit of elastic collisions and zero Coulomb friction at any roughness. The high-velocity tails of both distribution functions seem to follow stretched exponentials even in the presence of Coulomb friction, and the related velocity exponents deviate strongly from a gaussian with increasing friction.

Emittance growth due to beam-gas scattering

International Nuclear Information System (INIS)

Raubenheimer, T.O.

1992-06-01

The effect of beam-gas scattering on beam emittance is examined by deriving the beam distribution function. The distribution function is found by treating the beam-gas scattering as a filtered Poisson process and calculating the cumulants of the distribution. (author)

Strategic regulation of gas transport

International Nuclear Information System (INIS)

Nese, Gjermund; Straume, Odd Rune

2005-01-01

The basis of the article has been the steadily increasing focus particularly from EU, on increased competition in the natural gas markets. This could influence the profit distribution between the gas producing and consuming counties which is an important problem situation for Norway as a gas producer. The gas market value chain consist of three parts (production, transport and distribution). How the countries may use strategic regulation of the transport tariff for the transport and distribution systems in order to move as much as possible of the total profit to the part of the value chain in control is studied. The focus has been on how increased competition influences the incentives of the authorities through low or high transport tariff and to what extent increased competition influences the welfare level in the producer and consumer counties when strategic regulations of the transport occur. The analysis is based on a theoretical model developed in 2005. Some central mechanisms related to the natural gas market are mapped and Norway may counteract some negative effects of liberalisation of the European gas market through strategic adaptation of the transport tariff to the Norwegian gas transport systems

Size distribution and concentration of soot generated in oil and gas-fired residential boilers under different combustion conditions

Science.gov (United States)

Jiménez, Santiago; Barroso, Jorge; Pina, Antonio; Ballester, Javier

2016-05-01

In spite of the relevance of residential heating burners in the global emission of soot particles to the atmosphere, relatively little information on their properties (concentration, size distribution) is available in the literature, and even less regarding the dependence of those properties on the operating conditions. Instead, the usual procedure to characterize those emissions is to measure the smoke opacity by several methods, among which the blackening of a paper after filtering a fixed amount of gas (Bacharach test) is predominant. In this work, the size distributions of the particles generated in the combustion of a variety of gaseous and liquid fuels in a laboratory facility equipped with commercial burners have been measured with a size classifier coupled to a particle counter in a broad range of operating conditions (air excesses), with simultaneous determination of the Bacharach index. The shape and evolution of the distribution with progressively smaller oxygen concentrations depends essentially on the state of the fuel: whereas the combustion of the gases results in monomodal distributions that 'shift' towards larger diameters, in the case of the gas-oils an ultrafine mode is always observed, and a secondary mode of coarse particle grows in relevance. In both cases, there is a strong, exponential correlation between the total mass concentration and the Bacharach opacity index, quite similar for both groups of fuels. The empirical expressions proposed may allow other researchers to at least estimate the emissions of numerous combustion facilities routinely characterized by their smoke opacities.

Gas prices and price process

International Nuclear Information System (INIS)

Groenewegen, G.G.

1992-01-01

On a conference (Gas for Europe in the 1990's) during the Gasexpo '91 the author held a speech of which the Dutch text is presented here. Attention is paid to the current European pricing methods (prices based on the costs of buying, transporting and distributing the natural gas and prices based on the market value, which is deducted from the prices of alternative fuels), and the transparency of the prices (lack of information on the way the prices are determined). Also attention is paid to the market signal transparency and gas-gas competition, which means a more or less free market of gas distribution. The risks of gas-to-gas competition for a long term price stability, investment policies and security of supply are discussed. Opposition against the Third Party Access (TPA), which is the program to implement gas-to-gas competition, is caused by the fear of natural gas companies for lower gas prices and lower profits. Finally attention is paid to government regulation and the activities of the European Commission (EC) in this matter. 1 fig., 6 ills., 1 tab

Partner's interest conflict analysis in distribution of natural gas: a game theory approach; Analise de conflitos de interesse na distribuicao de gas natural em areas urbanas: uma aplicacao da teoria dos jogos

Energy Technology Data Exchange (ETDEWEB)

Prata, Bruno de Athayde; Arruda, Joao Bosco Furtado [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Nucleo de Pesquisa em Logistica, Transporte e Desenvolvimento

2004-07-01

The use of Natural Gas is nowadays increasing in Brazilian scene and this fact shows the necessity of effective planning tasks in that sector. In the case of Natural Gas Vehicular (NGV) distribution one can face problems of actor's (distributor, retailers, customers and non-users) point of view conflicts and fuel stations expand in most Brazilian urban areas in an uncontrolled way, despising counties regulation on land use. This paper reports a study using a model based in Game Theory concepts to determine some key-variables as the number of fuel stations which must deliver NGV in a given study area. Although some information could not be available the results of simulation shows the usefulness of using such an approach to give solutions to distribution questions in NGV sector. The model was applied to the case of a district in Fortaleza city which is the study area of a project entitled Projeto GASLOG presently on process under the sponsoring of Brazilian Government, PETROBRAS and Brazilian GasEnergy Research Network. (author)

PAHs distribution in sediments associated with gas hydrate and oil seepage from the Gulf of Mexico.

Science.gov (United States)

Wang, Cuiping; Sun, Hongwen; Chang, Ying; Song, Zhiguang; Qin, Xuebo

2011-12-01

Six sediment samples collected from the Gulf of Mexico were analyzed. Total concentrations of the PAHs ranged from 52 to 403 ng g(-1) dry weight. The lowest PAH concentration without 5-6 rings PAHs appeared in S-1 sample associated with gas hydrate or gas venting. Moreover, S-1 sample had the lowest organic carbon content with 0.85% and highest reduced sulfur level with 1.21% relative to other samples. And, analysis of the sources of PAHs in S-1 sample indicated that both pyrogenic and petrogenic sources, converserly, while S-8, S-10 and S-11 sample suggested petrogenic origin. The distribution of dibenzothiophene, fluorine and dibenzofuran and the maturity parameters of triaromatic steranes suggested that organic matters in S-1 sample were different from that in S-8, S-10 and S-11 sample. This study suggested that organic geochemical data could help in distinguish the characteristic of sediment associated with gas hydrate or with oil seepage. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of biomass-generated producer gas constituents on cell growth, product distribution and hydrogenase activity of Clostridium carboxidivorans P7T

International Nuclear Information System (INIS)

Ahmed, Asma; Cateni, Bruno G.; Huhnke, Raymond L.; Lewis, Randy S.

2006-01-01

In our previous work, we demonstrated that biomass-generated producer gas can be converted to ethanol and acetic acid using a microbial catalyst Clostridium carboxidivorans P7 T . Results showed that the producer gas (1) induced cell dormancy, (2) inhibited H 2 consumption, and (3) affected the acetic acid/ethanol product distribution. Results of this work showed that tars were the likely cause of cell dormancy and product redistribution and that the addition of a 0.025μm filter in the gas cleanup negated the effects of tars. C. carboxidivorans P7 T can adapt to the tars (i.e. grow) only after prolonged exposure. Nitric oxide, present in the producer gas at 150ppm, is an inhibitor of the hydrogenase enzyme involved in H 2 consumption. We conclude that significant conditioning of the producer gas will be required for the successful coupling of biomass-generated producer gas with fermentation to produce ethanol and acetic acid. (author)

Natural gas distribution system for Peninsular Malaysia. Malaysia ni okeru toshi gas jigyo no sosetsu

Energy Technology Data Exchange (ETDEWEB)

Ohashi, T [Tokyo Gas Co. Ltd., Tokyo (Japan)

1993-03-30

Tokyo Gas Co., Ltd. established in 1992 Gas Malaysia Sdn. Bhd, a joint venture company with investments from the Malaysia side, and begun full-fledged activities for supplying natural gas in Peninsular Malaysia. This paper explains the summary of the project. With a background of affluent resources including natural gas reserve of 1.9 trillion m[sup 3] as of 1992, Malaysia is promoting various projects to diversify and refine local energy consumption patterns and improve petroleum exporting capacity. The said joint venture project is one of the international bids executed by the national petroleum company, Petronas, in which Tokyo Gas Co., Ltd. and Mitsui and Co., Ltd. were selected as their partner. The company business includes supply and sales of petroleum, as well as construction of pipelines to support the former activities. Engineers have been either stationed or sent to the country as technical cooperation including necessary technical transfer. This project is highly significant in terms of contributing to growth of economy in both countries and to solving global environmental problems. 6 figs.

Welfare effects of unbundling gas storage and distribution

International Nuclear Information System (INIS)

Breton, M.; Montreal Univ., PQ; Kharbach, M.

2006-01-01

The creation of inventories and stockpiles can help to reduce price and production fluctuations. This paper presented the results of a simulation of market architectures using a 2 period model. The aim of the paper was to provide insights on the merits of a gas unbundling policy recently adopted in many gas markets. In terms of market architecture, it was first assumed that one of the gas firms owned the storage facility and was mandated to give a second firm access to it. It was then assumed that an independent third firm was responsible for the storage activity so that the other 2 firms competed in the downstream gas market and bought storage services from the independent firm. High and low price periods in a single year were considered. The first architecture assumed an Open Access framework which introduced a Stackelberg competition component in the downstream market through the storage participation in the final goods offering. The second architecture assumed an independent storage activity, and a Cournot component was present. Seasonal storage facilities were filled during the low price period and emptied during the high price period. Results of the simulation indicated that total welfare and consumer welfare were maximized in the case of the integrated firm owning the storage facilities and operating in the downstream market. Success was attributed to the Open Access framework and the Stackelberg competition component in the downstream market. The bundled architecture led to higher consumer surplus than the unbundled architecture. It was concluded that regulatory reforms in North American and European gas sectors that foster separating storage and merchant activities can not be justified based on welfare arguments. 12 refs., 1 tab

Restructuring local distribution services: Possibilities and limitations

Energy Technology Data Exchange (ETDEWEB)

Duann, D.J.

1994-08-01

The restructuring of local distribution services is now the focus of the natural gas industry. It is the last major step in the ``reconstitution`` of the natural gas industry and a critical clement in realizing the full benefits of regulatory and market reforms that already have taken place in the wellhead and interstate markets. It could also be the most important regulatory initiative for most end-use customers because they are affected directly by the costs and reliability of distribution services. Several factors contribute to the current emphasis on distribution service restructuring. They include the unbundling and restructuring of upstream markets, a realization of the limitations of supply-side options (such as gas procurement oversight), and the increased diversity and volatility of gas demand facing local distribution companies. Local distribution service is not one but a series of activities that start with commodity gas procurement and extend to transportation, load balancing, storage, and metering and billing of services provided. There are also considerable differences in the economies of scale and scope associated with these various activities. Thus, a mixture of supply arrangements (such as a competitive market or a monopoly) is required for the most efficient delivery of local distribution services. A distinction must be made between the supply of commodity gas and the provision of a bundled distribution service. This distinction and identification of the best supply arrangements for various distribution service components are the most critical factors in developing appropriate restructuring policies. For most state public utility commissions the criteria for service restructuring should include pursuing the economies of scale and scope in gas distribution, differentiating and matching gas service reliability and quality with customer requirements, and controlling costs associated with the search, negotiation, and contracting of gas services.

Projecting changes in the distribution and productivity of living marine resources: A critical review of the suite of modelling approaches used in the large European project VECTORS

NARCIS (Netherlands)

Peck, Myron A.; Arvanitidis, Christos; Butenschön, Momme; Canu, Donata Melaku; Chatzinikolaou, Eva; Cucco, Andrea; Domenici, Paolo; Fernandes, Jose A.; Gasche, Loic; Huebert, Klaus B.; Hufnagl, Marc; Jones, Miranda C.; Kempf, Alexander; Keyl, Friedemann; Maar, Marie; Mahévas, Stéphanie; Marchal, Paul; Nicolas, Delphine; Pinnegar, John K.; Rivot, Etienne; Rochette, Sébastien; Sell, Anne F.; Sinerchia, Matteo; Solidoro, Cosimo; Somerfield, Paul J.; Teal, Lorna R.; Travers-trolet, Morgan; De Wolfshaar, Van Karen E.

2018-01-01

We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of

Pesticides in the atmosphere: a comparison of gas-particle partitioning and particle size distribution of legacy and current-use pesticides

Science.gov (United States)

Degrendele, C.; Okonski, K.; Melymuk, L.; Landlová, L.; Kukučka, P.; Audy, O.; Kohoutek, J.; Čupr, P.; Klánová, J.

2016-02-01

This study presents a comparison of seasonal variation, gas-particle partitioning, and particle-phase size distribution of organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in air. Two years (2012/2013) of weekly air samples were collected at a background site in the Czech Republic using a high-volume air sampler. To study the particle-phase size distribution, air samples were also collected at an urban and rural site in the area of Brno, Czech Republic, using a cascade impactor separating atmospheric particulates according to six size fractions. Major differences were found in the atmospheric distribution of OCPs and CUPs. The atmospheric concentrations of CUPs were driven by agricultural activities while secondary sources such as volatilization from surfaces governed the atmospheric concentrations of OCPs. Moreover, clear differences were observed in gas-particle partitioning; CUP partitioning was influenced by adsorption onto mineral surfaces while OCPs were mainly partitioning to aerosols through absorption. A predictive method for estimating the gas-particle partitioning has been derived and is proposed for polar and non-polar pesticides. Finally, while OCPs and the majority of CUPs were largely found on fine particles, four CUPs (carbendazim, isoproturon, prochloraz, and terbuthylazine) had higher concentrations on coarse particles ( > 3.0 µm), which may be related to the pesticide application technique. This finding is particularly important and should be further investigated given that large particles result in lower risks from inhalation (regardless the toxicity of the pesticide) and lower potential for long-range atmospheric transport.

Análisis de la distribución espacial de estrellas, gas y polvo en galaxias cercanas = Analysis of the spacial distribution of stars, gas and dust in nearby galaxies

OpenAIRE

Muñoz Mateos, Juan Carlos

2010-01-01

El objetivo principal de esta tesis consiste en cuantificar la distribución espacial de las propiedades físicas de las estrellas, el gas y el polvo en galaxias cercanas, dado que son el registro fósil de su evolución pasada. En particular, nos centraremos sobre todo en las variaciones de estas propiedades con la distancia al centro de las galaxias espirales.[ABSTRACT]The main goal of this thesis is to quantify the spatial distribution of the physical properties of stars, gas and d...

Análisis de la distribución espacial de estrellas, gas y polvo en galaxias cercanas = Analysis of the spacial distribution of stars, gas and dust in nearby galaxies

OpenAIRE

Muñoz Mateos, Juan Carlos

2011-01-01

El objetivo principal de esta tesis consiste en cuantificar la distribución espacial de las propiedades físicas de las estrellas, el gas y el polvo en galaxias cercanas, dado que son el registro fósil de su evolución pasada. En particular, nos centraremos sobre todo en las variaciones de estas propiedades con la distancia al centro de las galaxias espirales.[ABSTRACT]The main goal of this thesis is to quantify the spatial distribution of the physical properties of stars, gas and d...

Dependence of charge collection distributions and dose on the gas type filling the ionization chamber for a p(66)Be(49) clinical neutron beam

International Nuclear Information System (INIS)

Awschalom, M.; Haken, R.K.T.

1985-01-01

Measurements of central axis depth charge distributions (CADCD) in a p(66)Be(49) clinical neutron beam using A-150 TE plastic ionization chambers (IC) have shown that these distributions are dependent on the gas type filling the ICs. IC volumes from 0.1 to 8 cm 3 and nine different gases were investigated. Off axis ratios and build-up measurements do not seem to be as sensitive to gas type. The gas dosimetry constants given in the AAPM Protocol for Neutron Beam Dosimetry for air and methane based TE gases were tested for consistency in water and in TE solution filled phantoms at depths of 10 cm, when used in conjunction with an IC having 5 mm thick walls of A-150. 29 refs., 7 figs., 1 tab

Live insertion method used for main renewal

International Nuclear Information System (INIS)

Solkowitz, M.

1992-01-01

Baltimore Gas and Electric's pilot project using the live insertion method to replace a cast iron main provided excellent results. Its use on Eastern Avenue, a major state highway, was cost effective, provided gas service to customers during the work, required relatively short construction time and resulted in only minor traffic disruptions. Gas service transfers to the new main were done at customer convenience and resulted in outages of only a few hours per customer. This paper reports that the project involved inserting a 6-in. plastic line inside an existing 10-in. cast iron main. Miller Pipeline Corp., Indianapolis, supplier of the Insertec left-angle R right-angle live insertion method was contracted for the job. Miller technicians assisted BG and E forces by providing a load analysis of the main, a pushing machine and related supplies, foaming equipment and pipe cutting tools. Company forces were responsible for all preparatory work, including opening all excavations, installing bypasses, and fusing and testing the plastic pipe. Service transfers and renewals were also completed by company employees

A Web Services based system for the distribution of live information at the FTU fusion experiment

International Nuclear Information System (INIS)

Boncagni, L.; Centioli, C.; Lattanzio, L.; Panella, M.; Torelli, C.; Zaccarian, L.

2009-01-01

In this paper we describe LiveMonitor, an integrated system realized for the distribution of information in fusion environments. The software tool is based on a client-server approach, where the server side consists of a set of Web Services that collect data from a variety of data sources. LiveMonitor has been successfully used at FTU, replacing and enhancing part of the core of the current message broadcasting system. The tool integrates all the information needed by the control room personnel during the experiments, namely the shot sequence status coming from the FTU Control System, videos of the plasma discharge from the FTU ports cameras, and fresh data from the databases. From the hardware point of view, the new system is made of a Linux node running the Web Services, while clients running on other machines can display information on large (46 '' ) LCD monitors. The tool has been tested during FTU experiments and can be further expanded to match the needs of the control room personnel and experimental physicists.

Essentials of natural gas microturbines

CERN Document Server

Boicea, Valentin A

2013-01-01

Addressing a field which, until now, has not been sufficiently investigated, Essentials of Natural Gas Microturbines thoroughly examines several natural gas microturbine technologies suitable not only for distributed generation but also for the automotive industry. An invaluable resource for power systems, electrical, and computer science engineers as well as operations researchers, microturbine operators, policy makers, and other industry professionals, the book: Explains the importance of natural gas microturbines and their use in distributed energy resource (DER) systemsDiscusses the histor

[The reconstruction of two-dimensional distributions of gas concentration in the flat flame based on tunable laser absorption spectroscopy].

Science.gov (United States)

Jiang, Zhi-Shen; Wang, Fei; Xing, Da-Wei; Xu, Ting; Yan, Jian-Hua; Cen, Ke-Fa

2012-11-01

The experimental method by using the tunable diode laser absorption spectroscopy combined with the model and algo- rithm was studied to reconstruct the two-dimensional distribution of gas concentration The feasibility of the reconstruction program was verified by numerical simulation A diagnostic system consisting of 24 lasers was built for the measurement of H2O in the methane/air premixed flame. The two-dimensional distribution of H2O concentration in the flame was reconstructed, showing that the reconstruction results reflect the real two-dimensional distribution of H2O concentration in the flame. This diagnostic scheme provides a promising solution for combustion control.

Evaluation of RSG-GAS purification system and pool warm water layer supplier performance

International Nuclear Information System (INIS)

Sudiyono; Suhadi; Diah-Erlina-Lestari

2005-01-01

Function of RSG-GAS purification system and warm water supplier (KBE 02) are to pick up dissolve activation result and another dirts of warm water layer. To keep quality of water at the decided level. The system is equipped by heater to supply warm water layer on the reactor pool surface the distribution is to reduce radiation level in the operation hall area a speciality on the reactor pool surface. Line KBE 02 tomord beam tube headitty system supplies water necessary to be shielding to beam tube in use off time. Of the RSG-GAS purification system and pool warm water layer performance date can be shown north of water is always in good condition. To require the dechded requirement. Resin live time is two years and then months

Natural gas industry R and D

International Nuclear Information System (INIS)

Pavan, S.

1992-01-01

The last three decades have witnessed significant developments in engineering relative to the distribution and use of natural gas. This paper reviews these developments which, in natural gas distribution, include - polyethylene conduits, the use of radar to trace buried conduits, telemetering, innovative pressure reducing techniques and equipment, optimized retrofitting of buried pipelines, leak detection techniques, and energy recovery systems applied to pressure reducing operations. Relative to the efficient combustion and new uses of natural gas, the paper reviews the state-of-the-art in the design of compact wall mounted gas fired boilers for building space heating, gas fuelled space heating ventilation and air conditioning systems, and natural gas fed fuel cells

The use of diagnostic imaging for identifying abnormal gas accumulations in cetaceans and pinnipeds.

Directory of Open Access Journals (Sweden)

Sophie eDennison

2012-06-01

Full Text Available Recent dogma suggested that marine mammals are not at risk of decompression sickness (DCS due to a number of evolutionary adaptations. Several proposed adaptations exist. Lung compression and alveolar collapse that terminate gas exchange before a depth is reached where supersaturation is significant and bradycardia with peripheral vasoconstriction affecting the distribution, and dynamics of blood and tissue nitrogen levels. Published accounts of gas and fat emboli and dysbaric osteonecrosis in marine mammals and theoretical modeling have challenged this view-point, suggesting that decompression-like symptoms may occur under certain circumstances, contrary to common belief. Diagnostic imaging modalities are invaluable tools for the non-invasive examination of animals for evidence of gas and have been used to demonstrate the presence of incidental decompression-related renal gas accumulations in some stranded cetaceans. Diagnostic imaging has also contributed to the recognition of clinically significant gas accumulations in live and dead cetaceans and pinnipeds. Understanding the appropriate application and limitations of the available imaging modalities is important for accurate interpretation of results. The presence of gas may be incidental and must be interpreted cautiously alongside all other available data including clinical examination, clinical laboratory testing, gas analysis, necropsy examination and histology results.

Life Cycle Energy Consumption and Greenhouse Gas Emissions Analysis of Natural Gas-Based Distributed Generation Projects in China

Directory of Open Access Journals (Sweden)

Hansi Liu

2017-10-01

Full Text Available In this paper, we used the life-cycle analysis (LCA method to evaluate the energy consumption and greenhouse gas (GHG emissions of natural gas (NG distributed generation (DG projects in China. We took the China Resources Snow Breweries (CRSB NG DG project in Sichuan province of China as a base scenario and compared its life cycle energy consumption and GHG emissions performance against five further scenarios. We found the CRSB DG project (all energy input is NG can reduce GHG emissions by 22%, but increase energy consumption by 12% relative to the scenario, using coal combined with grid electricity as an energy input. The LCA also indicated that the CRSB project can save 24% of energy and reduce GHG emissions by 48% relative to the all-coal scenario. The studied NG-based DG project presents major GHG emissions reduction advantages over the traditional centralized energy system. Moreover, this reduction of energy consumption and GHG emissions can be expanded if the extra electricity from the DG project can be supplied to the public grid. The action of combining renewable energy into the NG DG system can also strengthen the dual merit of energy conservation and GHG emissions reduction. The marginal CO2 abatement cost of the studied project is about 51 USD/ton CO2 equivalent, which is relatively low. Policymakers are recommended to support NG DG technology development and application in China and globally to boost NG utilization and control GHG emissions.

Transference and natural gas distribution system analysis utilizing hybrid modelling; Analise de sistemas de transferencia e distribuicao de gas natural utilizando modelagem hibrida

Energy Technology Data Exchange (ETDEWEB)

Calvo, Robson A.; Martinkoski, Ricardo [Centro Federal de Educacao Tecnologica do Parana (CEFET), Curitiba, PR (Brazil); Neves Junior, Flavio [Centro Federal de Educacao Tecnologica do Parana (CEFET), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Eletrica e Informatica Industrial

2003-07-01

The objective of this article is to apply techniques of formal specification in modelling of natural gas transmission and distribution systems. In this case the formal models are characterized by using hybrid automata. Initially the existent components in the net are modeled and represented by independent hybrid automata. The global dynamics is obtained through the product hybrid automata. Languages representing the desirable states of the system are obtained from the hybrid automata, allowing a hybrid control procedure. An automatic tool as SHIFT must be used to modelling and simulation. (author)

Biogeographic distribution and metric dental variation of fossil and living orangutans (Pongo spp.).

Science.gov (United States)

Tshen, Lim Tze

2016-01-01

The genus Pongo has a relatively richer Quaternary fossil record than those of the African great apes. Fossil materials are patchy in terms of anatomical parts represented, limited almost exclusively to isolated teeth, jaw and bone fragments. Fossil evidence indicates that the genus Pongo had a broadly continuous distribution across the southern part of the Indomalayan biogeographic region, ranging in time from Early Pleistocene to Holocene: southern China (77 fossil sites), Vietnam (15), Laos (6), Cambodia (2), Thailand (4), Peninsular Malaysia (6), Sumatra (4), Borneo (6) and Java (4). Within this distribution range, there are major geographical gaps with no known orangutan fossils, notably central and southern Indochina, central and southern Thailand, eastern Peninsular Malaysia, northern and southern Sumatra, and Kalimantan. The geological time and place of origin of the genus remain unresolved. Fossil orangutan assemblages usually show greater extent of dental metrical variation than those of modern-day populations. Such variability shown in prehistoric populations has partially contributed to confusion regarding past taxonomic diversity and systematic relationships among extinct and living forms. To date, no fewer than 14 distinct taxa have been identified and named for Pleistocene orangutans. Clear cases suggestive of predation by prehistoric human are few in number, and limited to terminal Pleistocene-Early Holocene sites in Borneo and a Late Pleistocene site in Vietnam.

Impact of airway gas exchange on the multiple inert gas elimination technique: theory.

Science.gov (United States)

Anderson, Joseph C; Hlastala, Michael P

2010-03-01

The multiple inert gas elimination technique (MIGET) provides a method for estimating alveolar gas exchange efficiency. Six soluble inert gases are infused into a peripheral vein. Measurements of these gases in breath, arterial blood, and venous blood are interpreted using a mathematical model of alveolar gas exchange (MIGET model) that neglects airway gas exchange. A mathematical model describing airway and alveolar gas exchange predicts that two of these gases, ether and acetone, exchange primarily within the airways. To determine the effect of airway gas exchange on the MIGET, we selected two additional gases, toluene and m-dichlorobenzene, that have the same blood solubility as ether and acetone and minimize airway gas exchange via their low water solubility. The airway-alveolar gas exchange model simulated the exchange of toluene, m-dichlorobenzene, and the six MIGET gases under multiple conditions of alveolar ventilation-to-perfusion, VA/Q, heterogeneity. We increased the importance of airway gas exchange by changing bronchial blood flow, Qbr. From these simulations, we calculated the excretion and retention of the eight inert gases and divided the results into two groups: (1) the standard MIGET gases which included acetone and ether and (2) the modified MIGET gases which included toluene and m-dichlorobenzene. The MIGET mathematical model predicted distributions of ventilation and perfusion for each grouping of gases and multiple perturbations of VA/Q and Qbr. Using the modified MIGET gases, MIGET predicted a smaller dead space fraction, greater mean VA, greater log(SDVA), and more closely matched the imposed VA distribution than that using the standard MIGET gases. Perfusion distributions were relatively unaffected.

Gas situation in the world; Sekai no gas jijo

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-04-10

The Chinese Government intends to totally prohibit the combustion of coal as is in 2000 onward to deal with environmental problems. To attain the coal, however, it will have to develop technologies for high-efficiency coal utilization, coal pulverization for power generation, and power generation not dependent on coal. Qatar and India signed a letter confirming their intention to enhance cooperation in the oil and gas sectors. It is predicted that natural gas consumption in the United States will renew its maximum record in 1998. In the last half of this year, Venezuela will open its natural gas distribution and transportation sectors to foreign investors. Itohchu Oil Exploration Co., Ltd., operated by Itohchu Corporation for natural resources exploration, won the first success in a foreign capital-led trial drilling in the Caspian Sea off Azerbaijan. Six U.S. corporations plan to participitate in a project of constructing an LNG receiving base and distribution network in Lebanon. Norway is making efforts to increase its sale of gas to the British market despite there are great quantities of inexpensive gas in Britain. Britain will put off the complete liberalization of electric retailing scheduled to be effectuated in April this year until September. The investment in the oil and gas upstream sectors across the world in 1997 is found to be two times larger than that of 1990

Infrared imaging spectroscopy of the Galactic center - Distribution and motions of the ionized gas

Science.gov (United States)

Herbst, T. M.; Beckwith, S. V. W.; Forrest, W. J.; Pipher, J. L.

1993-01-01

High spatial spectral resolution IR images of the Galactic center in the Br-gamma recombination line of hydrogen were taken. A coherent filament of gas extending from north of IRS 1, curving around IRS 16/Sgr A complex, and continuing to the southwest, is seen. Nine stellar sources have associated Br-gamma emission. The total Br-gamma line flux in the filament is approximately 3 x 10 exp -15 W/sq m. The distribution and kinematics of the northern arm suggest orbital motion; the observations are accordingly fit with elliptical orbits in the field of a central point of mass.

DISTRIBUTION OF THE TEMPERATURE IN THE ASH-GAS FLOW DURING KORYAKSKY VOLCANO ERUPTION IN 2009

Science.gov (United States)

Gordeev, E.; Droznin, V.

2009-12-01

The observations of the ash-gas plumes during the Koryaksky eruption in March 2009 by the high resolution thermovision camera allowed obtaining thermal distributions inside the ash-gas flows. The plume structure is formed by single emissions. They rise at the rate of 5.5-7 m/s. The plume structure in general is represented as 3 zones: 1. a zone of high heat exchange; 2. a zone of floating up; 3. a zone of lateral movement. The plume temperature within the zone of lateral movement exceeds the atmospheric temperature by 3-5 oC, within the zone of floating up it exceeds by 20 oC. Its rate within the zone of floating up comprises 5-7 m/s. At the boundary between the zones of high heat exchange and floating up where we know the plume section, from heat balance equation we can estimate steam rate and heat power of the fluid thermal flow. Power of the overheated steam was estimated as Q=35 kg/s. It forms the ash-gas plume from the eruption and has temperature equal to 450 oC. The total volume of water steam produced during 100 days of eruption was estimated 3*105 t, its energy - 109 MJ.

Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors

Directory of Open Access Journals (Sweden)

M. Cihan Çakır

2016-09-01

Full Text Available Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption–dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors.

Science.gov (United States)

Çakır, M Cihan; Çalışkan, Deniz; Bütün, Bayram; Özbay, Ekmel

2016-09-29

Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO) heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption-dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

Research on the internal pressure behavior of metal gas distribution pipelines with different types of tubing defects

Directory of Open Access Journals (Sweden)

Filip Stefan Mihai

2017-01-01

Full Text Available The paper aims to approach an important subject related to natural gas distribution networks which, depending on the expansion of the localities, are composed of intercommunicating pipes, pressure reducing stations and branch connections fittings. The urban networks are the most complex ones and the rural areas networks are the simplest. However, irrespective of their installation, they must meet the safety operating requirements as much as possible. According to standards, all these components must be tight and pressure resistant. In this regard, we intend to approach a very important issue related to the behavior of the tubular steel material showing corrosion and/or material defects, and to the internal stress caused by the gas pressure on the walls of the tubing material.

Methanol and ethanol vapor conversion in gas discharge with strongly non-uniform distribution of electric field on atmospheric pressure

International Nuclear Information System (INIS)

Golota, V.I.; Zavada, L.M.; Kotyukov, O.V.; Kudin, D.V.; Rodionov, S.V.; Pis'menetskoj, A.S.; Dotsenko, Yu.V.

2010-01-01

The barrierless gas discharge of negative polarity with strongly non-uniform distribution of electrical field in the methanol and ethanol vapour was studied. It is shown that level of methanol and ethanol conversion depended from power consumed by the discharge and exposition time for gas mixture in discharge zone. The condition for deep conversion of the methanol and ethanol vapours were determined. The water and carbon dioxide are the end products for the methanol and ethanol conversion. Formaldehyde and formic acid are the intermediates products in the conversion of methanol. And ethanol has a number of different compounds, including acetic acid, acetaldehyde, etc.

Decision NSUARB-NG-98: in the matter of the Gas Distribution Act and in the matter of franchise applications for the distribution of natural gas in the province of Nova Scotia

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-11-16

A decision was rendered following a public hearing conducted by the Nova Scotia Utility and Review Board (the Board) over 49 hearing days between April 12, 1999 and July 29, 1999, in the matter of applications for franchises to construct and operate natural gas delivery systems in the province of Nova Scotia under the authority of various acts. Part One of the report consists of the Board's findings on the province-wide franchise applications. Each application was evaluated in the context of the statutory, regulatory and policy criteria established by the Act and GIC Regulations. The Board drew from these criteria upon which its decision was based. A brief summary of the evidence provided by each applicant in respect of each key factor is presented, followed by the Board's findings in respect of that factor. Part two deals with the applications by the municipalities and co-operatives. A brief summary of each proposal is set out along with the Board's findings. Part three consists of comments by the Board in respect of other issues, including the regulatory environment, single end user franchises and municipal fees. Part four contains a summary of the Board's findings and conclusions. An addendum contains six schedules. Pursuant to Section 8 of the Gas Distribution Act, the Board granted a full regulation class franchise for a period of 25 years to Sempra Atlantic Gas Inc., subject to the approval of the Governor in Council and subject to the conditions set forth in Schedule 'A' attached; all other applications denied.

Evaluation of pulmonary gas distribution by the sup 133 Xe washout curve

Energy Technology Data Exchange (ETDEWEB)

Sato, Masao; Katsuragawa, Shigehiko [Iwate Medical Univ., Morioka (Japan). School of Medicine (Japan)

1989-10-01

The pulmonary mixing index (PMI) and DeltaN{sup 2} derived from an N{sup 2} washout curve by the multiple-breath method, and the K{sub 1}/K{sub 4} ratio (K{sub 1}, K{sub 4} are the rate constant of washout obtained from the fast space and slow space, respectively) derived from regional {sup 133}Xe washout curves were evaluated in 12 healthy subjects and 22 subjects with pulmonary disease, who included 12 subjects with chronic obstructive pulmonary disease (COPD), 5 subjects with pulmonary fibrosis (PF) and 5 subjects with bronchial asthma (BA). The results were as follows: (1) PMI was 0.68{plus minus}0.31% (mean{plus minus}SD) in the PF group, 1.34{plus minus}0.40% in the BA group and 8.63{plus minus}5.01% in the COPD group. The DeltaN{sub 2} was 0.20{plus minus}0.11%, 0.64{plus minus}0.24% and 5.96{plus minus}4.21%, respectively. (2) The K{sub 1}/K{sub 4} ratio in the right lung was linearly correlated with that of the left lung (r=0.84, p<0.001). (3) The regional K{sub 1}/K{sub 4} ratio (mean{plus minus}SE) in healthy subjects was lowest in the basal region of the right lung. (4) The regional gas distribution score (RGDS) derived from the regional K{sub 1}/K{sub 4} ratios was 18.8{plus minus}0.9 (mean{plus minus}SE) in the healthy 12 subjects, 19.0{plus minus}1.2 in the PF group, 11.8{plus minus}1.8 in the BA group and 6.5{plus minus}0.6 in the COPD group. It was concluded that RGDS was more sensitive and useful parameter than PMI and DeltaN{sub 2} for detecting the disturbance of pulmonary gas distribution. (author).

75 FR 13342 - Pipeline Safety: Workshop on Distribution Pipeline Construction

Science.gov (United States)

2010-03-19

... DEPARTMENT OF TRANSPORTATION Pipeline and Hazardous Materials Safety Administration [Docket ID... natural gas distribution construction. Natural gas distribution pipelines are subject to a unique subset... distribution pipeline construction practices. This workshop will focus solely on natural gas distribution...

Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

International Nuclear Information System (INIS)

1996-01-01

The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues

Model documentation Natural Gas Transmission and Distribution Model of the National Energy Modeling System. Volume 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-02-26

The Natural Gas Transmission and Distribution Model (NGTDM) of the National Energy Modeling System is developed and maintained by the Energy Information Administration (EIA), Office of Integrated Analysis and Forecasting. This report documents the archived version of the NGTDM that was used to produce the natural gas forecasts presented in the Annual Energy Outlook 1996, (DOE/EIA-0383(96)). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic approach, and provides detail on the methodology employed. Previously this report represented Volume I of a two-volume set. Volume II reported on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.

Gas quality analysis and evaluation program for project Gasbuggy

Energy Technology Data Exchange (ETDEWEB)

Smith, C F [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

Experimental results of the gas quality analysis program for Project Gasbuggy through August 1969 are presented graphically, addressing the questions raised by the preshot program goals. The chemical composition and the concentrations of tritium, krypton-85, carbon-14 and argon-37, 39 are presented as a function of time and gas production from the nuclear chimney. Chemically, the presence of CO{sub 2}, CO and H{sub 2} served to dilute the formation gas and caused reactions which significantly altered the gas composition at early times. The radionuclide content of the chimney gas at reentry was some 800 pCi/cm{sup 3} of which about 80% was CH{sub 3}T. Lesser quantities of tritium were observed as HT, C{sub 2}H{sub 5}T and C{sub 3}H{sub 7}T. The other major contaminant was Kr{sup 85} which was present at about one-fifth the level of CH{sub 3}T. Small quantities of carbon-14 and argon-39 were also identified. The only other radionuclides identified in the gas were relatively short-lived rare gases. During the production testing, about two and one-half chimney volumes of gas at formation pressure were removed. This removal, accompanied by dilution, has reduced the radionuclide concentrations to about 7% of their levels at reentry. The production characteristics of the Gasbuggy environment prevented an adequate test of the effectiveness of chimney flushing. However, the rapid drawdown concept is supported by the available data as an effective means of reducing contaminant levels. The changes in composition during production or testing are seen to be consistent with a model involving a non-uniform gas influx rate and flow distribution over the chimney region. Mixing times are estimated to be on the order of a few days, so that increasing concentrations following a sudden gas influx can be explained. (author)

Engineering Multifunctional Living Paints: Thin, Convectively-Assembled Biocomposite Coatings of Live Cells and Colloidal Latex Particles Deposited by Continuous Convective-Sedimentation Assembly

Science.gov (United States)

Jenkins, Jessica Shawn

Advanced composite materials could be revolutionized by the development of methods to incorporate living cells into functional materials and devices. This could be accomplished by continuously and rapidly depositing thin ordered arrays of adhesive colloidal latex particles and live cells that maintain stability and preserve microbial reactivity. Convective assembly is one method of rapidly assembling colloidal particles into thin (advantages over thicker randomly ordered composites, including enhanced cell stability and increased reactivity through minimized diffusion resistance to nutrients and reduced light scattering. This method can be used to precisely deposit live bacteria, cyanobacteria, yeast, and algae into biocomposite coatings, forming reactive biosensors, photoabsorbers, or advanced biocatalysts. This dissertation developed new continuous deposition and coating characterization methods for fabricating and characterizing 90 hours) photohydrogen production under anoxygenic conditions. Nutrient reduction slows cell division, minimizing coating outgrowth, and promotes photohydrogen generation, improving coating reactivity. Scanning electron microscopy of microstructure revealed how coating reactivity can be controlled by the size and distribution of the nanopores in the biocomposite layers. Variations in colloid microsphere size and suspension composition do not affect coating reactivity, but both parameters alter coating microstructure. Porous paper coated with thin coatings of colloidal particles and cells to enable coatings to be used in a gas-phase without dehydration may offer higher volumetric productivity for hydrogen production. Future work should focus on optimization of cell density, light intensity, media cycling, and acetate concentration.

Visualization of velocity field and phase distribution in gas-liquid two-phase flow by NMR imaging

International Nuclear Information System (INIS)

Matsui, G.; Monji, H.; Obata, J.

2004-01-01

NMR imaging has been applied in the field of fluid mechanics, mainly single phase flow, to visualize the instantaneous flow velocity field. In the present study, NMR imaging was used to visualize simultaneously both the instantaneous phase structure and velocity field of gas-liquid two-phase flow. Two methods of NMR imaging were applied. One is useful to visualize both the one component of liquid velocity and the phase distribution. This method was applied to horizontal two-phase flow and a bubble rising in stagnant oil. It was successful in obtaining some pictures of velocity field and phase distribution on the cross section of the pipe. The other is used to visualize a two-dimensional velocity field. This method was applied to a bubble rising in a stagnant water. The velocity field was visualized after and before the passage of a bubble at the measuring cross section. Furthermore, the distribution of liquid velocity was obtained. (author)

Evaluation of two typical distributed energy systems

Science.gov (United States)

Han, Miaomiao; Tan, Xiu

2018-03-01

According to the two-natural gas distributed energy system driven by gas engine driven and gas turbine, in this paper, the first and second laws of thermodynamics are used to measure the distributed energy system from the two parties of “quantity” and “quality”. The calculation results show that the internal combustion engine driven distributed energy station has a higher energy efficiency, but the energy efficiency is low; the gas turbine driven distributed energy station energy efficiency is high, but the primary energy utilization rate is relatively low. When configuring the system, we should determine the applicable natural gas distributed energy system technology plan and unit configuration plan according to the actual load factors of the project and the actual factors such as the location, background and environmental requirements of the project. “quality” measure, the utilization of waste heat energy efficiency index is proposed.

Modelling gas markets - a survey

International Nuclear Information System (INIS)

1997-01-01

This report reviews research of relevance to the analysis of present and future developments of the European natural gas market. The research activities considered are confined to (1) numerical models for gas markets, (2) analyses of energy demand, and (3) analyses of behaviour and cost structures in the transmission and distribution sector. Most of the market models are strictly micro economic and assume perfect competition or a game-theoretical equilibrium. They use sophisticated solution concepts, but very simplified specifications of supply and demand functions. Most of the research on demand is econometric analyses. These have more detailed model specification than have the aggregated market models. It is found, however, that the econometric literature based on neo-classical economics has not yielded unambiguous results and the specifications disregard important real world aspects of gas demand. The section on demand concludes that the extent of the gas grid is an important determinant for gas demand, but there has been virtually no research on what determines this variable. Data about transmission and distribution of gas in Europe is scarce and only a few non-econometric and virtually no econometric analyses are available. However, some conclusions can be made from relevant North American literature: (1) there has been significant autonomous technical progress in the transmission industry, (2) distribution costs strongly depend on geographical and other conditions, and (3) ownership, whether private or public, may be important for distribution costs and pricing policies. 56 refs., 3 figs., 1 tab

Modelling gas markets - a survey

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-31

This report reviews research of relevance to the analysis of present and future developments of the European natural gas market. The research activities considered are confined to (1) numerical models for gas markets, (2) analyses of energy demand, and (3) analyses of behaviour and cost structures in the transmission and distribution sector. Most of the market models are strictly micro economic and assume perfect competition or a game-theoretical equilibrium. They use sophisticated solution concepts, but very simplified specifications of supply and demand functions. Most of the research on demand is econometric analyses. These have more detailed model specification than have the aggregated market models. It is found, however, that the econometric literature based on neo-classical economics has not yielded unambiguous results and the specifications disregard important real world aspects of gas demand. The section on demand concludes that the extent of the gas grid is an important determinant for gas demand, but there has been virtually no research on what determines this variable. Data about transmission and distribution of gas in Europe is scarce and only a few non-econometric and virtually no econometric analyses are available. However, some conclusions can be made from relevant North American literature: (1) there has been significant autonomous technical progress in the transmission industry, (2) distribution costs strongly depend on geographical and other conditions, and (3) ownership, whether private or public, may be important for distribution costs and pricing policies. 56 refs., 3 figs., 1 tab.

Effects of biomass-generated producer gas constituents on cell growth, product distribution and hydrogenase activity of Clostridium carboxidivorans P7{sup T}

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Asma [Oklahoma State University, Stillwater, OK (United States). School of Chemical Engineering; Cateni, Bruno G.; Huhnke, Raymond L. [Oklahoma State University, Stillwater, OK (United States). Department of Biosystems and Agricultural Engineering; Lewis, Randy S. [Brigham Young University, Provo, UT (United States). Chemical Engineering Department

2006-07-15

In our previous work, we demonstrated that biomass-generated producer gas can be converted to ethanol and acetic acid using a microbial catalyst Clostridium carboxidivorans P7{sup T}. Results showed that the producer gas (1) induced cell dormancy, (2) inhibited H{sub 2} consumption, and (3) affected the acetic acid/ethanol product distribution. Results of this work showed that tars were the likely cause of cell dormancy and product redistribution and that the addition of a 0.025{mu}m filter in the gas cleanup negated the effects of tars. C. carboxidivorans P7{sup T} can adapt to the tars (i.e. grow) only after prolonged exposure. Nitric oxide, present in the producer gas at 150ppm, is an inhibitor of the hydrogenase enzyme involved in H{sub 2} consumption. We conclude that significant conditioning of the producer gas will be required for the successful coupling of biomass-generated producer gas with fermentation to produce ethanol and acetic acid. (author)

Russian natural gas policy and its possible effects on European gas markets

International Nuclear Information System (INIS)

Quast, O.; Locatelli, C.

1997-01-01

There is a growing perception among Western European gas experts that Russia has developed a considerable gas surplus - the Russian gas bubble. Thus, the question clearly arises how much gas is available for export and how much gas, over the next 15 to 20 years, can the Russian quasi-monopolist Gazprom market in Western Europe. We consider that Gazprom's export strategy mirrors the approach of Russia's natural gas policy towards the Western European market. In this paper, we will focus on the characteristics of Gazprom's export strategy, its underlying logic, and its impact on Western European gas markets. As a consequence of Gazprom's export strategy, the Russian gas company faces today a price quantity dilemma. Gazprom's problem is to place as much gas as possible in the growing Western European gas market, without destroying downstream gas prices. We argue that Gazprom has adopted a market share expansion and downstream vertical integration strategy, aimed at capturing a part of the downstream gas rent. Although this strategy appears to have initiated a form of gas to gas competition in a number of European consumer markets, this strategy is not based on an aggressive price policy. However, in order to live up to its ambitions, there is a chance that Gazprom will have to somewhat relax traditional contract clauses, such as contract length, indexation terms and take or pay conditions. (author)

Pesticides in the atmosphere: a comparison of gas-particle partitioning and particle size distribution of legacy and current-use pesticides

Directory of Open Access Journals (Sweden)

C. Degrendele

2016-02-01

Full Text Available This study presents a comparison of seasonal variation, gas-particle partitioning, and particle-phase size distribution of organochlorine pesticides (OCPs and current-use pesticides (CUPs in air. Two years (2012/2013 of weekly air samples were collected at a background site in the Czech Republic using a high-volume air sampler. To study the particle-phase size distribution, air samples were also collected at an urban and rural site in the area of Brno, Czech Republic, using a cascade impactor separating atmospheric particulates according to six size fractions. Major differences were found in the atmospheric distribution of OCPs and CUPs. The atmospheric concentrations of CUPs were driven by agricultural activities while secondary sources such as volatilization from surfaces governed the atmospheric concentrations of OCPs. Moreover, clear differences were observed in gas-particle partitioning; CUP partitioning was influenced by adsorption onto mineral surfaces while OCPs were mainly partitioning to aerosols through absorption. A predictive method for estimating the gas-particle partitioning has been derived and is proposed for polar and non-polar pesticides. Finally, while OCPs and the majority of CUPs were largely found on fine particles, four CUPs (carbendazim, isoproturon, prochloraz, and terbuthylazine had higher concentrations on coarse particles ( >  3.0 µm, which may be related to the pesticide application technique. This finding is particularly important and should be further investigated given that large particles result in lower risks from inhalation (regardless the toxicity of the pesticide and lower potential for long-range atmospheric transport.

Will implementation of green gas into the gas supply be feasible in the future?

NARCIS (Netherlands)

Bekkering, J.; Hengeveld, E. J.; van Gemert, W. J. T.; Broekhuis, A. A.

2015-01-01

The energy efficiency, greenhouse gas reduction and cost price of a green gas supply chain were evaluated. The considered supply chain is based on co-digestion of dairy cattle manure and maize, biogas upgrading and injection into a distribution gas grid. A reference scenario was defined which

Outlook natural and renewable gas. 2017 gas adequacy report

International Nuclear Information System (INIS)

2017-01-01

Pursuant to Article L.141-10 of the French Energy Code, the managers of the gas distribution and transmission networks published jointly, and for the first time in 2016, a multi-year provisional assessment of gas demand and production in France. This document is an update of that first edition. It was developed in a collaborative process among managers of the distribution and transmission networks, which coordinated their analyses while taking into consideration recent changes in the energy sector. As the 2016 provisional assessment, this document presents three scenarios: a base reference scenario in line with the objectives of the multi-year energy program, and two framing scenarios

Greenhouse gas emissions from high demand, natural gas-intensive energy scenarios

International Nuclear Information System (INIS)

Victor, D.G.

1990-01-01

Since coal and oil emit 70% and 30% more CO 2 per unit of energy than natural gas (methane), fuel switching to natural gas is an obvious pathway to lower CO 2 emissions and reduced theorized greenhouse warming. However, methane is, itself, a strong greenhouse gas so the CO 2 advantages of natural gas may be offset by leaks in the natural gas recovery and supply system. Simple models of atmospheric CO 2 and methane are used to test this hypothesis for several natural gas-intensive energy scenarios, including the work of Ausubel et al (1988). It is found that the methane leaks are significant and may increase the total 'greenhouse effect' from natural gas-intensive energy scenarios by 10%. Furthermore, because methane is short-lived in the atmosphere, leaking methane from natural gas-intensive, high energy growth scenarios effectively recharges the concentration of atmospheric methane continuously. For such scenarios, the problem of methane leaks is even more serious. A second objective is to explore some high demand scenarios that describe the role of methane leaks in the greenhouse tradeoff between gas and coal as energy sources. It is found that the uncertainty in the methane leaks from the natural gas system are large enough to consume the CO 2 advantages from using natural gas instead of coal for 20% of the market share. (author)

Gas in Europe: a special report

International Nuclear Information System (INIS)

Ballay, U.; Griffiths, M.; Campbell, N.; Nielsen, H.H.; Quinlan, M.; Mollet, P.

1996-01-01

This special report looks at the natural gas industry in various European countries in six separate articles. Increasing demand in the commercial and domestic markets for natural gas suggests that the industry in east Germany is likely to boom. The sale of shares in Hungary's gas distribution companies is seen as a success, despite some early difficulties. Foreign companies are likely to be attracted to invest in the Czech Republic's regional gas distribution companies after their privatisation this summer. Norway expects to enjoy further expansion in the gas industry following Europe wide liberalisation. Gas demand in Italy is likely to rise by fifty per cent over the next five years. Differing rates of expansion in the Netherlands and Belgian gas industries are noted. Finally, the Scandinavian power generation market is likely to increase its use of gas due to environmental imperatives and economic efficiency. (UK)

The multi service cable network along a natural gas network for urban distribution; Reseau cable multiservice associe a un reseau de gaz naturel pour la consommation publique

Energy Technology Data Exchange (ETDEWEB)

Markovic, D.; Krsmanovic, Z. [NIS-Energogas (Yugoslavia)

2000-07-01

The paper discusses parallel construction and development of natural gas and telecommunications projects in Europe, with an emphasis on the situation in FR Yugoslavia. Deregulation of postal services has created an opportunity for joint construction of multipurpose cable networks and gas distribution systems. Advantages are shown of such joint construction of gas pipeline and cable systems, and the strategy of further development of telecommunications and gas supply projects in FR Yugoslavia is presented. (authors)

Partner's interest conflict analysis in distribution of natural gas: a game theory approach; Analise de conflitos de interesse na distribuicao de gas natural em areas urbanas: uma aplicacao da teoria dos jogos

Energy Technology Data Exchange (ETDEWEB)

Prata, Bruno de Athayde; Arruda, Joao Bosco Furtado [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Nucleo de Pesquisa em Logistica, Transporte e Desenvolvimento

2004-07-01

The use of Natural Gas is nowadays increasing in Brazilian scene and this fact shows the necessity of effective planning tasks in that sector. In the case of Natural Gas Vehicular (NGV) distribution one can face problems of actor's (distributor, retailers, customers and non-users) point of view conflicts and fuel stations expand in most Brazilian urban areas in an uncontrolled way, despising counties regulation on land use. This paper reports a study using a model based in Game Theory concepts to determine some key-variables as the number of fuel stations which must deliver NGV in a given study area. Although some information could not be available the results of simulation shows the usefulness of using such an approach to give solutions to distribution questions in NGV sector. The model was applied to the case of a district in Fortaleza city which is the study area of a project entitled Projeto GASLOG presently on process under the sponsoring of Brazilian Government, PETROBRAS and Brazilian GasEnergy Research Network. (author)

Will implementation of green gas into the gas supply be feasible in the future?

NARCIS (Netherlands)

Bekkering, Jan; Hengeveld, Evert Jan; van Gemert, Wim; Broekhuis, A.A.

Energy efficiency, greenhouse gas reduction and cost price of a green gas supply chain were evaluated. This supply chain is based on co-digestion of dairy cattle manure and maize, biogas upgrading and injection into a distribution gas grid. A defined reference scenario reflects the current state of

Will implementation of green gas into the gas supply be feasible in the future?

NARCIS (Netherlands)

Ir. J. Bekkering; prof. dr. Wim van Gemert; A.A. Broekhuis; Drs. E.J. Hengeveld

2015-01-01

energy efficiency, greenhouse gas reduction and cost price of a green gas supply chain were evaluated. This supply chain is based on co-digestion of dairy cattle manure and maize, biogas upgrading and injection into a distribution gas grid. A defined reference scenario reflects the current state of

Thermodynamic Modeling and Dispatch of Distributed Energy Technologies including Fuel Cell -- Gas Turbine Hybrids

Science.gov (United States)

McLarty, Dustin Fogle

Distributed energy systems are a promising means by which to reduce both emissions and costs. Continuous generators must be responsive and highly efficiency to support building dynamics and intermittent on-site renewable power. Fuel cell -- gas turbine hybrids (FC/GT) are fuel-flexible generators capable of ultra-high efficiency, ultra-low emissions, and rapid power response. This work undertakes a detailed study of the electrochemistry, chemistry and mechanical dynamics governing the complex interaction between the individual systems in such a highly coupled hybrid arrangement. The mechanisms leading to the compressor stall/surge phenomena are studied for the increased risk posed to particular hybrid configurations. A novel fuel cell modeling method introduced captures various spatial resolutions, flow geometries, stack configurations and novel heat transfer pathways. Several promising hybrid configurations are analyzed throughout the work and a sensitivity analysis of seven design parameters is conducted. A simple estimating method is introduced for the combined system efficiency of a fuel cell and a turbine using component performance specifications. Existing solid oxide fuel cell technology is capable of hybrid efficiencies greater than 75% (LHV) operating on natural gas, and existing molten carbonate systems greater than 70% (LHV). A dynamic model is calibrated to accurately capture the physical coupling of a FC/GT demonstrator tested at UC Irvine. The 2900 hour experiment highlighted the sensitivity to small perturbations and a need for additional control development. Further sensitivity studies outlined the responsiveness and limits of different control approaches. The capability for substantial turn-down and load following through speed control and flow bypass with minimal impact on internal fuel cell thermal distribution is particularly promising to meet local demands or provide dispatchable support for renewable power. Advanced control and dispatch

Optimization of lift gas allocation in a gas lifted oil field as non-linear optimization problem

Directory of Open Access Journals (Sweden)

Roshan Sharma

2012-01-01

Full Text Available Proper allocation and distribution of lift gas is necessary for maximizing total oil production from a field with gas lifted oil wells. When the supply of the lift gas is limited, the total available gas should be optimally distributed among the oil wells of the field such that the total production of oil from the field is maximized. This paper describes a non-linear optimization problem with constraints associated with the optimal distribution of the lift gas. A non-linear objective function is developed using a simple dynamic model of the oil field where the decision variables represent the lift gas flow rate set points of each oil well of the field. The lift gas optimization problem is solved using the emph'fmincon' solver found in MATLAB. As an alternative and for verification, hill climbing method is utilized for solving the optimization problem. Using both of these methods, it has been shown that after optimization, the total oil production is increased by about 4. For multiple oil wells sharing lift gas from a common source, a cascade control strategy along with a nonlinear steady state optimizer behaves as a self-optimizing control structure when the total supply of lift gas is assumed to be the only input disturbance present in the process. Simulation results show that repeated optimization performed after the first time optimization under the presence of the input disturbance has no effect in the total oil production.

2006 statistical data of the French gas industry

International Nuclear Information System (INIS)

2007-12-01

This document makes a synthesis of the 2006 results of the annual inquiry about the French natural gas industry: 1 - organization of the French gas market (production, transport, methane terminals, storage facilities, distribution, commercialization, main steps of the opening of the gas market in France); 2 - the 2006 gas year (consumption, imports, production, stockpiles); 3 - results of the 2006 inquiry: infrastructures (storage capacities, pipelines and distribution network), production (evolution of natural gas and industrial gases production, uses), transport (inputs and outputs, geographical origin of inputs in 2005 and 2006, raw imports evolution since 1973), storage (evolution of stockpiles variation), natural gas supplies (sectoral uses), supplies by region and by sector in 2006, consumption by sector; 4 - power generation by gas cogeneration in 2005 (plants characteristics, classification, cogeneration status (in TWh), regional distribution of plants); 5 - 2006 monthly changes (inputs, net imports, consumption and useful stockpile, consumption and net imports); 6 - international comparisons (gas share in the overall energy consumption, consumption per user, evolution of main sectors of consumption in some European countries since 1973); 7 - appendixes: French transportation network, main gas roads in Europe, European gas fluxes, 2006 energy status, gas statuses during the past three years. (J.S.)

Multi-gas interaction modeling on decorated semiconductor interfaces: A novel Fermi distribution-based response isotherm and the inverse hard/soft acid/base concept

Science.gov (United States)

Laminack, William; Gole, James

2015-12-01

A unique MEMS/NEMS approach is presented for the modeling of a detection platform for mixed gas interactions. Mixed gas analytes interact with nanostructured decorating metal oxide island sites supported on a microporous silicon substrate. The Inverse Hard/Soft acid/base (IHSAB) concept is used to assess a diversity of conductometric responses for mixed gas interactions as a function of these nanostructured metal oxides. The analyte conductometric responses are well represented using a combination diffusion/absorption-based model for multi-gas interactions where a newly developed response absorption isotherm, based on the Fermi distribution function is applied. A further coupling of this model with the IHSAB concept describes the considerations in modeling of multi-gas mixed analyte-interface, and analyte-analyte interactions. Taking into account the molecular electronic interaction of both the analytes with each other and an extrinsic semiconductor interface we demonstrate how the presence of one gas can enhance or diminish the reversible interaction of a second gas with the extrinsic semiconductor interface. These concepts demonstrate important considerations in the array-based formats for multi-gas sensing and its applications.

Modeling Gas Dynamics in California Sea Lions

Science.gov (United States)

2015-09-30

W. and Fahlman, A. (2009). Could beaked whales get the bends?. Effect of diving behaviour and physiology on modelled gas exchange for three species...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Modeling Gas Dynamics in California Sea Lions Andreas...to update a current gas dynamics model with recently acquired data for respiratory compliance (P-V), and body compartment size estimates in

Projecting changes in the distribution and productivity of living marine resources: A critical review of the suite of modelling approaches used in the large European project VECTORS

Science.gov (United States)

Peck, Myron A.; Arvanitidis, Christos; Butenschön, Momme; Canu, Donata Melaku; Chatzinikolaou, Eva; Cucco, Andrea; Domenici, Paolo; Fernandes, Jose A.; Gasche, Loic; Huebert, Klaus B.; Hufnagl, Marc; Jones, Miranda C.; Kempf, Alexander; Keyl, Friedemann; Maar, Marie; Mahévas, Stéphanie; Marchal, Paul; Nicolas, Delphine; Pinnegar, John K.; Rivot, Etienne; Rochette, Sébastien; Sell, Anne F.; Sinerchia, Matteo; Solidoro, Cosimo; Somerfield, Paul J.; Teal, Lorna R.; Travers-Trolet, Morgan; van de Wolfshaar, Karen E.

2018-02-01

We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of single life stages or the whole life cycle of species, 3) food web models, and 4) end-to-end models. Single pressures are rare and, in the future, models must be able to examine multiple factors affecting living marine resources such as interactions between: i) climate-driven changes in temperature regimes and acidification, ii) reductions in water quality due to eutrophication, iii) the introduction of alien invasive species, and/or iv) (over-)exploitation by fisheries. Statistical (correlative) approaches can be used to detect historical patterns which may not be relevant in the future. Advancing predictive capacity of changes in distribution and productivity of living marine resources requires explicit modelling of biological and physical mechanisms. New formulations are needed which (depending on the question) will need to strive for more realism in ecophysiology and behaviour of individuals, life history strategies of species, as well as trophodynamic interactions occurring at different spatial scales. Coupling existing models (e.g. physical, biological, economic) is one avenue that has proven successful. However, fundamental advancements are needed to address key issues such as the adaptive capacity of species/groups and ecosystems. The continued development of end-to-end models (e.g., physics to fish to human sectors) will be critical if we hope to assess how multiple pressures may interact to cause changes in living marine resources including the ecological and economic costs and trade-offs of different spatial management strategies. Given the strengths and weaknesses of the various types of models reviewed here, confidence in projections of changes in the

Natural gas contracts in efficient portfolios

Energy Technology Data Exchange (ETDEWEB)

Sutherland, R.J.

1994-12-01

This report addresses the {open_quotes}contracts portfolio{close_quotes} issue of natural gas contracts in support of the Domestic Natural Gas and Oil Initiative (DGOI) published by the U.S. Department of Energy in 1994. The analysis is a result of a collaborative effort with the Public Service Commission of the State of Maryland to consider {open_quotes}reforms that enhance the industry`s competitiveness{close_quotes}. The initial focus of our collaborative effort was on gas purchasing and contract portfolios; however, it became apparent that efficient contracting to purchase and use gas requires a broader consideration of regulatory reform. Efficient portfolios are obtained when the holder of the portfolio is affected by and is responsible for the performance of the portfolio. Natural gas distribution companies may prefer a diversity of contracts, but the efficient use of gas requires that the local distribution company be held accountable for its own purchases. Ultimate customers are affected by their own portfolios, which they manage efficiently by making their own choices. The objectives of the DGOI, particularly the efficient use of gas, can be achieved when customers have access to suppliers of gas and energy services under an improved regulatory framework. The evolution of the natural gas market during the last 15 years is described to account for the changing preferences toward gas contracts. Long-term contracts for natural gas were prevalent before the early 1980s, primarily because gas producers had few options other than to sell to a single pipeline company, and this pipeline company, in turn, was the only seller to a gas distribution company.

Steelmaking gas prediction system; Sistema de predicao de gas de aciaria

Energy Technology Data Exchange (ETDEWEB)

Diniz, Pedro Henrique Boaventura; Sampaio, William Genelhu [USIMINAS, Ipatinga, MG (Brazil)

2011-12-21

The Usiminas, Steelmaking Plant located in Ipatinga - MG, has the necessity to complement its energy matrix with additional fuel (oil derived from petroleum presently). Despite the high cost of this fuel, 24,3% of the LDG gas was wasted due to inadequate size of the LDG gas holder and the inappropriate tool to manage the distribution of the fuel. This paper presents how the Steelmaking Gas Prediction System was developed aiming to improve its management and other actions to increase the gas usage minimizing the matrix complementation. (author)

Effects of short-term pressure-controlled ventilation on gas exchange, airway pressures, and gas distribution in patients with acute lung injury/ARDS: comparison with volume-controlled ventilation.

Science.gov (United States)

Prella, Maura; Feihl, François; Domenighetti, Guido

2002-10-01

The potential clinical benefits of pressure-controlled ventilation (PCV) over volume-controlled ventilation (VCV) in patients with acute lung injury (ALI) or ARDS still remain debated. We compared PCV with VCV in patients with ALI/ARDS with respect to the following physiologic end points: (1) gas exchange and airway pressures, and (2) CT scan intrapulmonary gas distribution at end-expiration. Prospective, observational study. A multidisciplinary ICU in a nonuniversity, acute-care hospital. Ten patients with ALI or ARDS (9 men and 1 woman; age range, 17 to 80 years). Sequential ventilation in PCV and VCV with a constant inspiratory/expiratory ratio, tidal volume, respiratory rate, and total positive end-expiratory pressure; measurement of gas exchange and airway pressures; and achievement of CT sections at lung base, hilum, and apex for the quantitative analysis of lung densities and of aerated vs nonaerated zones. PaO(2), PaCO(2), and PaO(2)/fraction of inspired oxygen ratio levels did not differ between PCV and VCV. Peak airway pressure (Ppeak) was significantly lower in PCV compared with VCV (26 +/- 2 cm H(2)O vs 31 +/- 2 cm H(2)O; p mean +/- SEM). The surface areas of the nonaerated zones as well as the total areas at each section level were unchanged in PCV compared with VCV, except at the apex level, where there was a significantly greater nonaerated area in VCV (11 +/- 2 cm(2) vs 9 +/- 2 cm(2); p mean CT number of each lung (20 lungs from 10 patients) was similar in the two modes, as were the density values at the basal and apical levels; the hilum mean CT number was - 442 +/- 28 Hounsfield units (HU) in VCV and - 430 +/- 26 HU in PCV (p lower Ppeaks through the precise titration of the lung distending pressure, and might be applied to avoid regional overdistension by means of a more homogeneous gas distribution.

Suggestion for a natural gas development policy

International Nuclear Information System (INIS)

Drummond, P.H.

1987-01-01

First, this work presents some aspects concerning the reserves and the future of natural gas consumption in Brazil. Then, from the results of a case-study about the implementation of a natural gas distribution company in Fortaleza (Ceara), we analyse under which conditions the business of natural gas distribution is economically interesting (subject of the M.Sc. thesis developed by the author). In possession of this results, the author proposes directions for a Natural Gas Policy in Brazil, approaching also aspects of Tariffs Policy. (author)

Natural gas - an alternative. Swedish electric power from Norwegian natural gas

International Nuclear Information System (INIS)

1986-10-01

The report describes the possible substitution of electric power by natural gas on the heat source market and how gas can be used for power production. The cost of distribution and means of supply are presented. 1/3 of the electric power produced by nuclear power plants can be replaced by the middle of the nineties. Transport techniques for gas and its total volume as well as transport cost from Norwegian North Sea are discussed

The gas industry in Spain

International Nuclear Information System (INIS)

Jego, H.

1999-01-01

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

Angular distributions of low kinetic energy photoelectrons in one- and two-photon ionisation of rare gas atoms

International Nuclear Information System (INIS)

O'Keeffe, P; Bolognesi, P; Avaldi, L; Richter, R; Moise, A; Cleva, P De; Mihelic, A

2012-01-01

The angular distributions of electrons emitted in the photoionisation of rare gas atoms using one and two photons are presented. The one-photon results show that these differential measurements can provide complementary information on the photoionisation event with respect to the measurement of the total absorption cross section while the two photon ionization allows additional parameters to be extracted from the experiments thus permitting a more complete description of the photoionisation dynamics.

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

Science.gov (United States)

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

2017-10-01

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

The relationship between the industry of natural gas and the sector of electric power: perspectives for the united development of such segments in Bahia; Estudo da industria do gas natural e sua relacao com o setor eletrico na Bahia: perspectivas para uma integracao sinergica entre tais segmentos

Energy Technology Data Exchange (ETDEWEB)

Prates, Daniel O. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Rocha, Georges S. [Bahia Univ., Salvador, BA (Brazil). Dept. de Engenharia Quimica. Curso de Especializacao em Engenharia do Gas Natural

2005-07-01

The industry of natural gas is finding great inter-relationship with the electric power section due to aspects technical, economical and institutional. In Brazil, this world tendency is increasing quickly, above all, starting from the crisis of energy lived by the Country in 2001. In spite of, in spite of being the third producing largest and consume-pain in Brazil, Bahia now is deficient in natural gas, committing the thermal-electricity generation due to lack of this energy one as well as, of the deficiency in the transport and distribution infrastructure. Besides, Bahia is the Brazilian state with the largest population without access the electric power. This motivates reflections concerning the potentialities of the natural gas to lessen this situation. Therefore, this work has an objective to evaluate the structures of the industry of the natural gas and the electric section in Bahia and the relationship among these segments. Initially, it tries to present the reasons that it is taking the development of the electric power generation in consonance with the industry of the gas. Soon afterwards, it comes a retrospective abbreviation of the electric power generation in Brazil and in Bahia, emphasizing the recent tendency of use of the natural gas for the thermal-electricity generation. In the following point, it talks about the reservations and production of natural gas and he/she comes the structure of commercialization of gas from the production/importation to the distribution in Brazil and in Bahia. To proceed, the investment plans are evaluated for the enlargement of the production, transport and distribution of natural gas and electricity in Bahia. Finally, the article is concluded being discussed the difficulties and perspectives of increase and integration of the segments of natural gas and electric power in Bahia, tends in view the institutional aspects, technique and economical of a model that influences the use of the natural gas and contribute to the

Carbon isotope evidence for the latitudinal distribution and wind speed dependence of the air-sea gas transfer velocity

International Nuclear Information System (INIS)

Krakauer, Nir Y.

2006-01-01

The air-sea gas transfer velocity is an important determinant of the exchange of gases, including CO 2 , between the atmosphere and ocean, but the magnitude of the transfer velocity and what factors control it remains poorly known. Here, we use oceanic and atmospheric observations of 14 C and 13 C to constrain the global mean gas transfer velocity as well as the exponent of its wind speed dependence, utilizing the distinct signatures left by the air-sea exchange of 14 CO 2 and 13 CO 2 . While the atmosphere and ocean inventories of 14 CO 2 and 13 CO 2 constrain the mean gas transfer velocity, the latitudinal pattern in the atmospheric and oceanic 14 C and 13 C distributions contain information about the wind speed dependence. We computed the uptake of bomb 14 C by the ocean for different transfer velocity patterns using pulse response functions from an ocean general circulation model, and evaluated the match between the predicted bomb 14 C concentrations and observationally based estimates for the 1970s-1990s. Using a wind speed climatology based on satellite measurements, we solved either for the best-fit global relationship between gas exchange and mean wind speed or for the mean gas transfer velocity over each of 11 ocean regions. We also compared the predicted consequences of different gas exchange relationships on the rate of change and interhemisphere gradient of 14 C in atmospheric CO 2 with tree-ring and atmospheric measurements. Our results suggest that globally, the dependence of the air-sea gas transfer velocity on wind speed is close to linear, with an exponent of 0.5 ± 0.4, and that the global mean gas transfer velocity at a Schmidt number of 660 is 20 ± 3 cm/hr, similar to the results of previous analyses. We find that the air-sea flux of 13 C estimated from atmosphere and ocean observations also suggests a lower than quadratic dependence of gas exchange on wind speed

Approaching hydrate and free gas distribution at the SUGAR-Site location in the Danube Delta

Science.gov (United States)

Bialas, Joerg; Dannowski, Anke; Zander, Timo; Klaeschen, Dirk; Klaucke, Ingo

2017-04-01

Gas hydrates did receive a lot of attention over the last decades when investigating their potential to serve as a possible source for Methane production. Among other world-wide programs the German SUGAR project sets out to investigate the entire chain from exploitation to production in Europe. Therefore research in the scope of the SUGAR project sets out to investigate a site in European EEZ for the detailed studies of hydrate and gas distribution in a permeable sediment matrix. Among others one aim of the project is to provide in situ samples of natural methane hydrate for further investigations by MEBO drilling. The Danube paleo-delta with its ancient canyon and levee systems was chosen as a possible candidate for hydrate formation within the available drilling range of 200 m below seafloor. In order to decide on the best drilling location cruise MSM34 (Bialas et al., 2014) of the German RV MARIA S MERIAN set out to acquire geophysical, geological and geochemical datasets for assessment of the hydrate content within the Danube paleo-delta, Black Sea. The Black Sea is well known for a significant gas content in the sedimentary column. Reports on observations of bottom simulating reflectors (BSR) by Popescu et al. (2007) and others indicate that free gas and hydrate occurrence can be expected within the ancient passive channel levee systems. A variety of inverted reflection events within the gas hydrate stability zone (GHSZ) were observed within the drilling range of MEBO and chosen for further investigation. Here we report on combined seismic investigations of high-resolution 2D & 3D multichannel seismic (MCS) acquisition accompanied by four component Ocean-Bottom-Seismometer (OBS) observations. P- and converted S-wave arrivals within the OBS datasets were analysed to provide overall velocity depth models. Due to the limited length of profiles the majority of OBS events are caused by near vertical reflections. While P-wave events have a significant lateral

Gas and energy technology 2006

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-05-15

Norway has a long tradition as an energy producing nation. No other country administers equally large quantities of energy compared to the number of inhabitants. Norway faces great challenges concerning the ambitions of utilizing natural gas power and living up to its Kyoto protocol pledges. Tekna would like to contribute to increased knowledge about natural gas and energy, its possibilities and technical challenges. Topics treated include carrying and employing natural gas, aspects of technology, energy and environment, hydrogen as energy carrier, as well as other energy alternatives, CO{sub 2} capture and the value chain connected to it.

INFORMATION FOR GAS USERS

CERN Multimedia

Logistics Group

2001-01-01

The contractor for the supply and distribution of pressurised gases has drawn our attention to the large number of gas bottles and banks being stored on the site for increasingly long periods. Users are reminded that the rental charges for gas bottles and banks are based on a progressive rate depending on their period of use. To assist CERN in its efforts to optimise its operations in this field, you are kindly requested : to return empty or unused containers to the official gas distribution points as soon as possible, to try to limit reserve stocks, bearing in mind that standardised gases can be delivered within 36 hours. This will result in a higher turnover rate and in increased safety and will improve the availability of the gases. For all further enquiries, please contact Gas.Store@cern.ch by e-mail or call 72265. Thank you for your co-operation.

Information for gas users

CERN Multimedia

2003-01-01

The contractor for the supply and distribution of pressurised gases has drawn our attention to the large number of gas bottles and banks being stored on the site for increasingly long periods. Users are reminded that the rental charges for gas bottles and banks are based on a progressive rate depending on their period of use. To assist CERN in its efforts to optimise its operations in this field, you are kindly requested: - to return empty or unused containers to the official gas distribution points as soon as possible - to try to limit reserve stocks, bearing in mind that standardised gases can be delivered within 36 hours. This will result in a higher turnover rate and in increased safety and will improve the availability of the gases. For all further enquiries, please contact "Gas store" by e-mail. Thank you for your co-operation. Logistics Group SPL Division

Relaxation distribution function of intracellular dielectric zones as an indicator of tumorous transition of living cells.

Science.gov (United States)

Thornton, B S; Hung, W T; Irving, J

1991-01-01

The response decay data of living cells subject to electric polarization is associated with their relaxation distribution function (RDF) and can be determined using the inverse Laplace transform method. A new polynomial, involving a series of associated Laguerre polynomials, has been used as the approximating function for evaluating the RDF, with the advantage of avoiding the usual arbitrary trial values of a particular parameter in the numerical computations. Some numerical examples are given, followed by an application to cervical tissue. It is found that the average relaxation time and the peak amplitude of the RDF exhibit higher values for tumorous cells than normal cells and might be used as parameters to differentiate them and their associated tissues.

Gas Bubble Migration and Trapping in Porous Media: Pore-Scale Simulation

Science.gov (United States)

Mahabadi, Nariman; Zheng, Xianglei; Yun, Tae Sup; van Paassen, Leon; Jang, Jaewon

2018-02-01

Gas bubbles can be naturally generated or intentionally introduced in sediments. Gas bubble migration and trapping affect the rate of gas emission into the atmosphere or modify the sediment properties such as hydraulic and mechanical properties. In this study, the migration and trapping of gas bubbles are simulated using the pore-network model extracted from the 3D X-ray image of in situ sediment. Two types of bubble size distribution (mono-sized and distributed-sized cases) are used in the simulation. The spatial and statistical bubble size distribution, residual gas saturation, and hydraulic conductivity reduction due to the bubble trapping are investigated. The results show that the bubble size distribution becomes wider during the gas bubble migration due to bubble coalescence for both mono-sized and distributed-sized cases. And the trapped bubble fraction and the residual gas saturation increase as the bubble size increases. The hydraulic conductivity is reduced as a result of the gas bubble trapping. The reduction in hydraulic conductivity is apparently observed as bubble size and the number of nucleation points increase.

Gas emergency management - safety and reliability of supply - remote management of distribution system through computer assisted dispatching of emergency events; Gestion des urgences - securite et fiabilite de la distribution du gaz gestion des urgences a l'aide d'un systeme informatique integre

Energy Technology Data Exchange (ETDEWEB)

Bettin, B.; Clava, R.; Pisino, F. [italgas, Torino (Italy); Guerra, M. [A.M.G.A., (Italy)

2000-07-01

Gas distribution companies have long since paid great attention to improving the quality and safety of the gas supply service to the consumer. In particular the management of gas emergencies has always been a responsibility taken seriously by all sectors of the gas industry. Over the last few years, however, the concept and practices in risk management have been changing rapidly. This has involved gas companies in an on-going attempt to successfully define and establish clear computer assisted risk management practices. Risk management is the systematic use of management policy, procedures and means, with the aim to protect employees, the public, the environment and properties at an acceptable cost. This paper has the purpose of presenting: - the computer software of gas emergency management in use at Italgas S.p.A. for testing the performance of gas distribution networks on a 'real-time' basis and therefore selecting effective action for solving any emergency that may occur; - the integrated system, implemented by A.M.G.A. (Azienda Mediterranea Gas e Acqua S.p.A. - Genova), for real-time management of gas and water network emergencies (reported by customers or by tele-alarm systems), their location, and the dispatching of operative crews. (authors)

Open discovery: An integrated live Linux platform of Bioinformatics tools.

Science.gov (United States)

Vetrivel, Umashankar; Pilla, Kalabharath

2008-01-01

Historically, live linux distributions for Bioinformatics have paved way for portability of Bioinformatics workbench in a platform independent manner. Moreover, most of the existing live Linux distributions limit their usage to sequence analysis and basic molecular visualization programs and are devoid of data persistence. Hence, open discovery - a live linux distribution has been developed with the capability to perform complex tasks like molecular modeling, docking and molecular dynamics in a swift manner. Furthermore, it is also equipped with complete sequence analysis environment and is capable of running windows executable programs in Linux environment. Open discovery portrays the advanced customizable configuration of fedora, with data persistency accessible via USB drive or DVD. The Open Discovery is distributed free under Academic Free License (AFL) and can be downloaded from http://www.OpenDiscovery.org.in.

Measuring trace gas emission from multi-distributed sources using vertical radial plume mapping (VRPM) and backward Lagrangian stochastic (bLS) techniques

Science.gov (United States)

Two micrometeorological techniques for measuring trace gas emission rates from distributed area sources were evaluated using a variety of synthetic area sources. The accuracy of the vertical radial plume mapping (VRPM) and the backward Lagrangian (bLS) techniques with an open-path optical spectrosco...

Energy distributions of an ion in a radio-frequency trap immersed in a buffer gas under the influence of additional external forces

Science.gov (United States)

Rouse, I.; Willitsch, S.

2018-04-01

An ion held in a radio-frequency trap interacting with a uniform buffer gas of neutral atoms develops a steady-state energy distribution characterized by a power-law tail at high energies instead of the exponential decay characteristic of thermal equilibrium. We have previously shown that the Tsallis statistics frequently used as an empirical model for this distribution is a good approximation when the ion is heated due to a combination of micromotion interruption and exchange of kinetic energy with the buffer gas [Rouse and Willitsch, Phys. Rev. Lett. 118, 143401 (2017), 10.1103/PhysRevLett.118.143401]. Here, we extend our treatment to include the heating due to additional motion of the ion caused by external forces, including the "excess micromotion" induced by uniform electric fields and rf phase offsets. We show that this also leads to a Tsallis distribution with a potentially different power-law exponent from that observed in the absence of this additional forced motion, with the difference increasing as the ratio of the mass of the neutral atoms to that of the ion decreases. Our results indicate that unless the excess micromotion is minimized to a very high degree, then even a system with very light neutrals and a heavy ion does not exhibit a thermal distribution.

A Comparison of Producer Gas, Biochar, and Activated Carbon from Two Distributed Scale Thermochemical Conversion Systems Used to Process Forest Biomass

Directory of Open Access Journals (Sweden)

Nathaniel Anderson

2013-01-01

Full Text Available Thermochemical biomass conversion systems have the potential to produce heat, power, fuels and other products from forest biomass at distributed scales that meet the needs of some forest industry facilities. However, many of these systems have not been deployed in this sector and the products they produce from forest biomass have not been adequately described or characterized with regards to chemical properties, possible uses, and markets. This paper characterizes the producer gas, biochar, and activated carbon of a 700 kg h−1 prototype gasification system and a 225 kg h−1 pyrolysis system used to process coniferous sawmill and forest residues. Producer gas from sawmill residues processed with the gasifier had higher energy content than gas from forest residues, with averages of 12.4 MJ m−3 and 9.8 MJ m−3, respectively. Gases from the pyrolysis system averaged 1.3 MJ m−3 for mill residues and 2.5 MJ m−3 for forest residues. Biochars produced have similar particle size distributions and bulk density, but vary in pH and carbon content. Biochars from both systems were successfully activated using steam activation, with resulting BET surface area in the range of commercial activated carbon. Results are discussed in the context of co-locating these systems with forest industry operations.

The Swedish municipal food distribution service to the elderly living at home as experienced by the recipient's relatives.

Science.gov (United States)

Pajalic, Zada

2013-07-23

The municipal Food distribution service (FD) to the elderly living at home is a part of the public social and care service in Sweden, The objective of this service is to ensure proper food intake for persons who are unable to do their own shopping, and prepare their own meals. The foremost reasons for the need of the FD service are in situations where there are illness related physical or psychological limitations.This means that the Swedish welfare system takes on the responsibility for its citizens when they have a legal social related need of care. Further, according to the Swedish social legislation, children or other relatives have no legal obligations to take care of their parents or elderly disabled relatives. This also means that the children or relatives of elderly people requiring social support have no legal right to be involved in the evaluation procedure of need assessment or the outcome of any social and care services granted by the Swedish social welfare system. The aim of the present study was to gain insight into how the relatives of elderly people living at home in Sweden experience the municipal service of ready-made meals distributed daily. The data was collected using in-depth interviews with relatives of elderly persons who use the municipal food distribution (FD) service (n=8). The transcribed interview material was analysed using the grounded theory method. The findings of this study revealed that the relatives of the municipal FD service recipients advocate for a food preparation service in the home of the recipient rather than the distribution of ready-made meals from a central kitchen. The results also revealed that the participating relatives felt frustrated by the legal limitations that make it impossible for them to influence the municipal FD service. The findings in this study also indicate that relatives should be considered as a resource in this matter and could actively participate, and have a positive influence on the quality of

Numerical Study on Flow, Temperature, and Concentration Distribution Features of Combined Gas and Bottom-Electromagnetic Stirring in a Ladle

Directory of Open Access Journals (Sweden)

Yang Li

2018-01-01

Full Text Available A novel method of combined argon gas stirring and bottom-rotating electromagnetic stirring in a ladle refining process is presented in this report. A three-dimensional numerical model was adopted to investigate its effect on improving flow field, eliminating temperature stratification, and homogenizing concentration distribution. The results show that the electromagnetic force has a tendency to spiral by spinning clockwise on the horizontal section and straight up along the vertical section, respectively. When the electromagnetic force is applied to the gas-liquid two phase flow, the gas-liquid plume is shifted and the gas-liquid two phase region is extended. The rotated flow driven by the electromagnetic force promotes the scatter of bubbles. The temperature stratification tends to be alleviated due to the effect of heat compensation and the improved flow. The temperature stratification tends to disappear when the current reaches 1200 A. The improved flow field has a positive influence on decreasing concentration stratification and shortening the mixing time when the combined method is imposed. However, the alloy depositing site needs to be optimized according to the whole circulatory flow and the region of bubbles to escape.

Experimental and Numerical Modelling of CO2 Atmospheric Dispersion in Hazardous Gas Emission Sites.

Science.gov (United States)

Gasparini, A.; sainz Gracia, A. S.; Grandia, F.; Bruno, J.

2015-12-01

Under stable atmospheric conditions and/or in presence of topographic depressions, CO2 concentrations can reach high values resulting in lethal effect to living organisms. The distribution of denser than air gases released from the underground is governed by gravity, turbulence and dispersion. Once emitted, the gas distribution is initially driven by buoyancy and a gas cloud accumulates on the ground (gravitational phase); with time the density gradient becomes less important due to dispersion or mixing and gas distribution is mainly governed by wind and atmospheric turbulence (passive dispersion phase). Natural analogues provide evidences of the impact of CO2 leakage. Dangerous CO2 concentration in atmosphere related to underground emission have been occasionally reported although the conditions favouring the persistence of such a concentration are barely studied.In this work, the dynamics of CO2 in the atmosphere after ground emission is assessed to quantify their potential risk. Two approaches have been followed: (1) direct measurement of air concentration in a natural emission site, where formation of a "CO2 lake" is common and (2) numerical atmospheric modelling. Two sites with different morphology were studied: (a) the Cañada Real site, a flat terrain in the Volcanic Field of Campo de Calatrava (Spain); (b) the Solforata di Pomezia site, a rough terrain in the Alban Hills Volcanic Region (Italy). The comparison between field data and model calculations reveal that numerical dispersion models are capable of predicting the formation of CO2 accumulation over the ground as a consequence of underground gas emission. Therefore, atmospheric modelling could be included as a valuable methodology in the risk assessment of leakage in natural degassing systems and in CCS projects. Conclusions from this work provide clues on whether leakage may be a real risk for humans and under which conditions this risk needs to be included in the risk assessment.

Change Management in public sector: A case study of gas distribution firm

Directory of Open Access Journals (Sweden)

Alireza Shirvani

2013-06-01

Full Text Available This paper considers different approaches for establishment of change management in governmental agencies. The proposed model of this paper uses Kotter’s 8-step method in an empirical investigation for a gas distribution firm located in province of Esfahan, Iran. The results of this study reveal that the organization was successful to create sense of urgency, form a powerful coalition, create a vision for change, communicate the vision, create short-term wins and build on the change. However, the organization was not successful on removing obstacles and changes in corporate culture. In addition, the sixth step, create short -term wins, receives the highest rate of success while removing the obstacles maintains the minimum rate of success. Finally, the survey demonstrates that gender and educational background do not have any impact on change management but age, job experience as well as job position influences change management, significantly.

Natural gas: an environmental-friendly solution?

International Nuclear Information System (INIS)

Vermeire, J.

1994-01-01

Since 1970, the portion of natural gas in energy consumption in Western-Europe has grown by 6 percent per year on the average. About 20 percent of the energy demand in Western-Europe is now covered by natural gas. It is forecasted that this growth will continue at a rate of 2 percent per year until 2010. The natural gas consumption will increase from 325 billion cubic metres in 1993 to 450 billion cubic metres per year in 2010. For the coming 10 to 15 years, the natural gas demand is covered by long-term contracts with gas producing countries. From 2010 on, additional contracts, covering 70 to 120 billion cubic metres per year are required. A shift in geographic distribution of countries from which natural gas will be imported by Western-European countries is expected, which implies high investments and additional costs for transport and distribution of natural gas. Due to its qualities with respect to environmental impact, yield, availability, and advanced technology, natural gas is the energy vector of the 21 first century. (A.S.)

Natural gas in 1936: Petroleum in 1936: The gas and oil fields in the Guelph and Medina (Grimsby) formations: Appendix, the Brownsville Gas Field: Gas and oil in eastern Ontario. Annual publication

Energy Technology Data Exchange (ETDEWEB)

Harkness, R B; Evans, C S

1938-12-31

Part V of this annual report consists of four separate reports: Natural gas, petroleum, gas and oil fields in the Guelph and Medina (Grimsby) formations, and gas and oil in eastern Ontario. The natural gas report discusses production and distribution; changes and improvements; consumption and rates; gas wells and their production; and licenses issued. The logs of wells are also included, being presented alphabetically by counties, townships, and owners, respectively. The petroleum report presents information on production and drilling by township; expansion; and petroleum importation and refining operations.

Natural gas monthly, August 1994

Energy Technology Data Exchange (ETDEWEB)

1994-08-24

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information.

Natural gas monthly, November 1993

International Nuclear Information System (INIS)

1993-01-01

The Natural Gas Monthly (NGM) highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground state data are also reported. From time to time, the NGM features articles designed to assist readers in using and interpreting natural gas information

Substitution of petroleum liquefied gas for natural gas in a metallurgical industry: a case study; Substituicao de gas liquefeito de petroleo por gas natural em uma siderurgica: um estudo de caso

Energy Technology Data Exchange (ETDEWEB)

Pessoa, Isac Quintao; Miranda, Luciano Lellis; Fullin Junior, Benjamin; Rodrigues, Henrique de Castro; Manella, Roberto [Aperam South America, Timoteo, MG (Brazil). Utilidades e Eficiencia Energetica; Lins, Vanessa de Freitas Cunha [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Quimica

2011-12-21

Minas Gerais is a State where there is no production of natural gas. Aiming to increase the consumption of natural gas in Minas Gerais, PETROBRAS increase the network of gas natural distribution in the State of Minas Gerais and the State concessionaire (GASMIG) installed the Project of Natural Gas Valley. The case study is associated to an enterprise that firmed contract for supplying of natural gas. The fuel to be substituted is the Liquefied Petroleum Gas and the results of the substitution were shown. The advantages of the substitution were related to costs, and environmental aspects with the reduction of CO{sub 2} production. The natural gas contains a lower content of impurities and is operated with higher safety than the petroleum liquefied gas. (author)

Estimation of Potential Shale Gas Yield Amount and Land Degradation in China by Landcover Distribution regarding Water-Food-Energy and Forest

Science.gov (United States)

Kim, N.; Heo, S.; Lim, C. H.; Lee, W. K.

2017-12-01

Shale gas is gain attention due to the tremendous reserves beneath the earth. The two known high reservoirs are located in United States and China. According to U.S Energy Information Administration China have estimated 7,299 trillion cubic feet of recoverable shale gas and placed as world first reservoir. United States had 665 trillion cubic feet for the shale gas reservoir and placed fourth. Unlike the traditional fossil fuel, spatial distribution of shale gas is considered to be widely spread and the reserved amount and location make the resource as energy source for the next generation. United States dramatically increased the shale gas production. For instance, shale gas production composes more than 50% of total natural gas production whereas China and Canada shale gas produce very small amount of the shale gas. According to U.S Energy Information Administration's report, in 2014 United States produced shale gas almost 40 billion cubic feet per day but China only produced 0.25 billion cubic feet per day. Recently, China's policy had changed to decrease the coal powerplants to reduce the air pollution and the energy stress in China is keep increasing. Shale gas produce less air pollution while producing energy and considered to be clean energy source. Considering the situation of China and characteristics of shale gas, soon the demand of shale gas will increase in China. United States invested 71.7 billion dollars in 2013 but it Chinese government is only proceeding fundamental investment due to land degradation, limited water resources, geological location of the reservoirs.In this study, firstly we reviewed the current system and technology of shale gas extraction such as hydraulic Fracturing. Secondly, listed the possible environmental damages, land degradations, and resource demands for the shale gas extraction. Thirdly, invested the potential shale gas extraction amount in China based on the location of shale gas reservoirs and limited resources for the

Differential accumulation and distribution of natural gas and its main controlling factors in the Sinian Dengying Fm, Sichuan Basin

Directory of Open Access Journals (Sweden)

Shugen Liu

2015-01-01

Full Text Available In order to disclose the genetic relationship between the hydrocarbon reservoirs and the transformation mechanism between ancient and modern gas reservoirs in the Sinian Dengying Fm in the Sichuan Basin, by using the drilling data, and geologic, geophysical and geochemical methods together, the differential accumulation and distribution of natural gas and its main controlling factors in this study area were identified following the idea of corroborating macroscopic, mesoscopic and microscopic results each other. The results demonstrate as follows. (1 The crude oil in the paleo-oil reservoirs of the Dengying Fm cracked into gas to form the early overpressure paleo-gas reservoirs 100 Ma. From 100 Ma to 20 Ma, the constant uplifting of the Sichuan Basin coupled with the shift of structural highs and the initial occurrence of Weiyuan anticline caused the adjustment of the early overpressure paleo-gas reservoirs into the late overpressure paleo-gas reservoirs. (2 With the increase of uplifting magnitude since 20 Ma, the formations overlying the Dengying Fm in Weiyuan structure experienced rapid erosion, resulting in decline of the caprock sealing ability and damage to the preservation conditions. Therefore, the natural gas in the Dengying Fm started to leak and dissipate from the eroded window of the Lower Triassic Jialingjiang Fm located on the top of the Weiyuan anticline, which is the beginning of the differential accumulation and dissipation of the natural gas in the Dengying Fm across the Sichuan Basin. During the process of the differential accumulation and dissipation, the gas below the spill point of the structural gas traps in Ziyang, Jinshi and Longnüsi–Moxi–Anpingdian–Gaoshiti areas migrated to the Weiyuan anticline along the unconformity of the Dengying Fm, and dissipated through the eroded window of the Jialingjiang Fm on the top of the Weiyuan anticline, resulting in a transformation of abnormal high pressure of gas reservoir

Distributed generation hits market

International Nuclear Information System (INIS)

Anon.

1997-01-01

The pace at which vendors are developing and marketing gas turbines and reciprocating engines for small-scale applications may signal the widespread growth of distributed generation. Loosely defined to refer to applications in which power generation equipment is located close to end users who have near-term power capacity needs, distributed generation encompasses a broad range of technologies and load requirements. Disagreement is inevitable, but many industry observers associate distributed generation with applications anywhere from 25 kW to 25 MW. Ten years ago, distributed generation users only represented about 2% of the world market. Today, that figure has increased to about 4 or 5%, and probably could settle in the 20% range within a 3-to-5-year period, according to Michael Jones, San Diego, Calif.-based Solar Turbines Inc. power generation marketing manager. The US Energy Information Administration predicts about 175 GW of generation capacity will be added domestically by 2010. If 20% comes from smaller plants, distributed generation could account for about 35 GW. Even with more competition, it's highly unlikely distributed generation will totally replace current market structures and central stations. Distributed generation may be best suited for making market inroads when and where central systems need upgrading, and should prove its worth when the system can't handle peak demands. Typical applications include small reciprocating engine generators at remote customer sites or larger gas turbines to boost the grid. Additional market opportunities include standby capacity, peak shaving, power quality, cogeneration and capacity rental for immediate demand requirements. Integration of distributed generation systems--using gas-fueled engines, gas-fired combustion engines and fuel cells--can upgrade power quality for customers and reduce operating costs for electric utilities

Gas phase ion chemistry

CERN Document Server

Bowers, Michael T

1979-01-01

Gas Phase Ion Chemistry, Volume 1 covers papers on the advances of gas phase ion chemistry. The book discusses the advances in flow tubes and the measurement of ion-molecule rate coefficients and product distributions; the ion chemistry of the earth's atmosphere; and the classical ion-molecule collision theory. The text also describes statistical methods in reaction dynamics; the state selection by photoion-photoelectron coincidence; and the effects of temperature and pressure in the kinetics of ion-molecule reactions. The energy distribution in the unimolecular decomposition of ions, as well

Greenhouse Gas Abatement with Distributed Generation in California's Commercial Buildings

International Nuclear Information System (INIS)

Stadler, Michael; Marnay, Chris; Cardoso, Goncalo; Megel, Olivier; Siddiqui, Afzal; Lai, Judy

2009-01-01

Lawrence Berkeley National Laboratory (LBL) is working with the California Energy Commission (CEC) to determine the role of distributed generation (DG) in greenhouse gas reductions. The impact of DG on large industrial sites is well known, and mostly, the potentials are already harvested. In contrast, little is known about the impact of DG on commercial buildings with peak electric loads ranging from 100 kW to 5 MW. We examine how DG with combined heat and power (CHP) may be implemented within the context of a cost minimizing microgrid that is able to adopt and operate various smart energy technologies, such as thermal and photovoltaic (PV) on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and storage systems. We use a mixed-integer linear program (MILP) that has the minimization of a site's annual energy costs as objective. Using 138 representative commercial sites in California (CA) with existing tariff rates and technology data, we find the greenhouse gas reduction potential for California's commercial sector. This paper shows results from the ongoing research project and finished work from a two year U.S. Department of Energy research project. To show the impact of the different technologies on CO2 emissions, several sensitivity runs for different climate zones within CA with different technology performance expectations for 2020 were performed. The considered sites can contribute between 1 Mt/a and 1.8 Mt/a to the California Air Resources Board (CARB) goal of 6.7Mt/a CO2 abatement potential in 2020. Also, with lower PV and storage costs as well as consideration of a CO2 pricing scheme, our results indicate that PV and electric storage adoption can compete rather than supplement each other when the tariff structure and costs of electricity supply have been taken into consideration. To satisfy the site's objective of minimizing energy costs, the batteries will be charged also by CHP systems during off-peak and mid-peak hours and

Gas-phase chemistry of Mo, Ru, W, and Os metal carbonyl complexes

International Nuclear Information System (INIS)

Wang, Y.; Qin, Z.; Fan, F.L.

2014-01-01

Metal carbonyl complexes were used for studying the gas-phase chemical behavior of Mo, Ru, W and Os isotopes with an on-line low temperature isothermal gas chromatography apparatus. Short-lived Mo and Ru isotopes were produced by a 252 Cf spontaneous fission source. Short-lived nuclides of W and Os were produced using the heavy ion reactions 19 F + 159 Tb and 165 Ho, respectively. Short-lived products were thermalized in a recoil chamber filled with a gas mixture of helium and carbon monoxide. The carbonyls formed were then transported through capillaries to an isothermal chromatography column for study of the adsorption behavior as a function of temperature. On-line isothermal chromatography (IC) experiments on Teflon (PTFE) and quartz surfaces showed that short-lived isotopes of the listed elements can form carbonyl complexes which are very volatile and interact most likely in physical sorption processes. Deduced adsorption enthalpies of Mo and Ru carbonyls were -38 ± 2 kJ/mol and -36 ± 2 kJ/mol, respectively. These values are in good agreement with literature data, partly obtained with different chromatographic techniques. A validation of the applied Monte Carlo model to deduce adsorption enthalpies with Mo isotopes of different half-lives proved the validity of the underlying adsorption model. The investigations using a gas-jet system coupled to a heavy ion accelerator without any preseparator clearly showed the limitations of the approach. The He and CO gas mixture, which was directly added into the chamber, will result in decomposition of CO gas and produce some aerosol particles. After the experiment of 173 W and 179 Os in the heavy ion experiments, the Teflon column was covered by a yellowish deposit; the adsorption enthalpy of W and Os carbonyls could therefore not be properly deduced using Monte Carlo simulations. (orig.)

Model documentation: Natural Gas Transmission and Distribution Model of the National Energy Modeling System; Volume 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-02-24

The Natural Gas Transmission and Distribution Model (NGTDM) is a component of the National Energy Modeling System (NEMS) used to represent the domestic natural gas transmission and distribution system. NEMS is the third in a series of computer-based, midterm energy modeling systems used since 1974 by the Energy Information Administration (EIA) and its predecessor, the Federal Energy Administration, to analyze domestic energy-economy markets and develop projections. This report documents the archived version of NGTDM that was used to produce the natural gas forecasts used in support of the Annual Energy Outlook 1994, DOE/EIA-0383(94). The purpose of this report is to provide a reference document for model analysts, users, and the public that defines the objectives of the model, describes its basic design, provides detail on the methodology employed, and describes the model inputs, outputs, and key assumptions. It is intended to fulfill the legal obligation of the EIA to provide adequate documentation in support of its models (Public Law 94-385, Section 57.b.2). This report represents Volume 1 of a two-volume set. (Volume 2 will report on model performance, detailing convergence criteria and properties, results of sensitivity testing, comparison of model outputs with the literature and/or other model results, and major unresolved issues.) Subsequent chapters of this report provide: (1) an overview of the NGTDM (Chapter 2); (2) a description of the interface between the National Energy Modeling System (NEMS) and the NGTDM (Chapter 3); (3) an overview of the solution methodology of the NGTDM (Chapter 4); (4) the solution methodology for the Annual Flow Module (Chapter 5); (5) the solution methodology for the Distributor Tariff Module (Chapter 6); (6) the solution methodology for the Capacity Expansion Module (Chapter 7); (7) the solution methodology for the Pipeline Tariff Module (Chapter 8); and (8) a description of model assumptions, inputs, and outputs (Chapter 9).

Distribution Integrity Management Plant (DIMP)

Energy Technology Data Exchange (ETDEWEB)

Gonzales, Jerome F. [Los Alamos National Laboratory

2012-05-07

This document is the distribution integrity management plan (Plan) for the Los Alamos National Laboratory (LANL) Natural Gas Distribution System. This Plan meets the requirements of 49 CFR Part 192, Subpart P Distribution Integrity Management Programs (DIMP) for the LANL Natural Gas Distribution System. This Plan was developed by reviewing records and interviewing LANL personnel. The records consist of the design, construction, operation and maintenance for the LANL Natural Gas Distribution System. The records system for the LANL Natural Gas Distribution System is limited, so the majority of information is based on the judgment of LANL employees; the maintenance crew, the Corrosion Specialist and the Utilities and Infrastructure (UI) Civil Team Leader. The records used in this report are: Pipeline and Hazardous Materials Safety Administration (PHMSA) 7100.1-1, Report of Main and Service Line Inspection, Natural Gas Leak Survey, Gas Leak Response Report, Gas Leak and Repair Report, and Pipe-to-Soil Recordings. The specific elements of knowledge of the infrastructure used to evaluate each threat and prioritize risks are listed in Sections 6 and 7, Threat Evaluation and Risk Prioritization respectively. This Plan addresses additional information needed and a method for gaining that data over time through normal activities. The processes used for the initial assessment of Threat Evaluation and Risk Prioritization are the methods found in the Simple, Handy Risk-based Integrity Management Plan (SHRIMP{trademark}) software package developed by the American Pipeline and Gas Agency (APGA) Security and Integrity Foundation (SIF). SHRIMP{trademark} uses an index model developed by the consultants and advisors of the SIF. Threat assessment is performed using questions developed by the Gas Piping Technology Company (GPTC) as modified and added to by the SHRIMP{trademark} advisors. This Plan is required to be reviewed every 5 years to be continually refined and improved. Records