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International Nuclear Information System (INIS)

... Nacional de Fusion, EURATOM-CIEMAT, Madrid (Spain) Krupnik, L. Chmyga,

Energy Technology Data Exchange (ETDEWEB)

A method to select, among several commercial diameter options, the most economic combination of pipeline networks is presented. These networks comply with the discharge conditions in the pipes and pressure in the knots. It is applied a static method for the hydraulics analysis of the Engineering Institute of the Universidad Nacional Autonoma de Mexico (UNAM) and an optimization technique to reduce the number of calculations. [Spanish] Se presenta un metodo para seleccionar, de entre varias opciones de diametros comerciales, la combinacion que forma la red de tuberias mas economica que satisface las condiciones de gasto en los tubos y de presion en los nudos de la misma. Para el analisis hidraulico se emplea un metodo estatico del Instituto de Ingenieria de la Universidad Nacional Autonoma de Mexico (UNAM) y se aplica una tecnica de optimacion para reducir el numero de calculos y alcanzar la solucion.

Energy Technology Data Exchange (ETDEWEB)

Secondary energy can be described as a surplus of electrical energy in a hydropower because the lower demand of energy in some period of the day and the excess of water in the reservoir during the rainy periods. This study proposes the using of the excess of energy at Itaipu Bi nacional for electrolytically hydrogen production and ammonia for nitrogenous fertilizers. Ammonia is a raw material for nitrogenous fertilizers synthesis and produced using hydrogen and nitrogen from the atmosphere. This paper determines the minimal cost of hydrogen production and the capacity of hydrogen production, with this data and according the ammonia market for nitrogenous fertilizers in the Centre/South region was estimated the better capacity of ammonia production for one plant near Itaipu. The process of ammonia production using energy excess is the most environmental acceptable. (author)

International Nuclear Information System (INIS)

This paper describes an electronic imaging system for producing real time neutron radiography from a low power research reactor, which will allow inspections of samples with high efficiency, in terms of measuring time and result analysis. This system has been implanted because of its potential use in various scientific and industrial areas where neutron radiography with photographic film could not be applied. This real time system is installed in neutron radiography facility of Argonauta nuclear research reactor, at the Instituto de Engenharia Nuclear of the Comissao Nacional de Energia Nuclear, in Brazil. It is adequate to perform real time neutron radiography of static and dynamic events of samples.

Energy Technology Data Exchange (ETDEWEB)

This paper presents the technical and economic studies performed by CEMIG, Companhia Energetica de Minas Gerais, Brazil, concerning the use of closing resistor in its extra-high voltage (EHV) breakers. The analysis emphasizes the advantages which could be achieved with the elimination of the resistor as far as costs and reliability are concerned. This evaluation was motivated by two 500 kV breaker failures resulting from the breakdown of the closing resistor operation mechanism. These occurrences resulted in operative restriction for CEMIG EHV system. The analysis demanded a review of the capability criteria of silicon carbide (Si C) gap arresters, which are still greatly used in CEMIG EHV System, and of the procedures to be applied when carrying out the transient studies. The investigation resulted in the prompt removal of closing resistors from circuit breakers in CEMIG extra-high voltage system generating an economy of approximately U$ 840,00 and an improvement ...

International Nuclear Information System (INIS)

Argentina has two operating PHWR nuclear power plants. Atucha I NPP is a pressure vessel type heavy water reactor of 360 MW e with 25 years of operation and Embalse NPP is a pressure tube type CANDU-600 reactor of 640 MW e. Atucha II, a third plant of 600 MW e of the pressure vessel type similar to Atucha I, is being constructed. NASA (Nucleoelectrica Argentina S.A.) currently operates both nuclear power plants. The National Atomic Energy Commission (Comision Nacional de Energia Atomica - CNEA) provides operational support to the plants, including research and development assistance, and actual technical services and maintenance work in different areas. The Chemistry Department, formerly the Reactor Chemistry Department has carried out project and support activities to the plants during the past 20 years. The aim of this work is to describe the present organization and the activities in reactor chemistry of the Chemistry Department. In particular, the projects to ...

International Nuclear Information System (INIS)

Biological wound dressings sterilized with gamma radiation, such as amnion and pig skin, are a reality in Mexico. These tissues are currently processed in the tissue bank and sterilized in the Gamma Industrial Irradiation Plant; both facilities belong to the Instituto Nacional de Investigaciones Nucleares (ININ) (National Institute of Nuclear Research). With the strong support of the International Atomic Energy Agency, the bank was established at the ININ and the Mexican Ministry of Health issued its sanitary license on July 7, 1999. The Quality Management System of the bank was certified by ISO 9001:2000 on August 1, 2003; the scope of the system is 'Research, Development and Processing of Biological Tissues Sterilized with Gamma Radiation'. At present, more than 150 patients from 16 hospitals have been successfully treated with these tissues. This paper presents a brief description of the tissue processing, as well as the present Mexican clinical experience with ...

Energy Technology Data Exchange (ETDEWEB)

Alter both oil crisis, of 1973 and 1979, a bad effect of the elevated costs and continuously increment of the oil prices was noted, for this reason, the interest for renewable energies sources widely available in developing countries was increased. All over the world, governments have formulated main objectives for energies savings and search for friendly technologies, taking into account the effects related with the environment. The imminent scarcity of fossil fuels has made humanity the rational use of primary energies, as a result of these; new plants with improved technology have been conceived taking into account energy savings and efficiency improvement. In this context, biomass gasification technologies are important, since they consist in techniques of parallel production of electricity and heat from just one fuel. This work consists in the development of a gasifier down draft of 100 kW for an internal combustion engine, which includes its sizing process and its energy ...

International Nuclear Information System (INIS)

We study the line widths in the [O III]#lambda#5007 and H#alpha# lines for two groups of planetary nebulae in the Milky Way bulge based upon spectroscopy obtained at the Observatorio Astronomico Nacional in the Sierra San Pedro Martir (OAN-SPM) using the Manchester Echelle Spectrograph. The first sample includes objects early in their evolution, having high H#beta# luminosities, but [O III]#lambda#5007/H#beta# < 3. The second sample comprises objects late in their evolution, with He II #lambda#4686/H#beta#>0.5. These planetary nebulae represent evolutionary phases preceding and following those of the objects studied by Richer et al. in 2008. Our sample of planetary nebulae with weak [O III]#lambda#5007 has a line width distribution similar to that of the expansion velocities of the envelopes of asymptotic giant branch stars and shifted to systematically lower values as compared to the less evolved objects studied by Richer et al. The sample with strong He II ...