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1

Calculation of the specific heat of magnetic impurities in the Anderson model of the resonant level; Calculo do calor especifico de impurezas magneticas no modelo de Anderson do nivel ressonante  

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

2008-07-01

2

AERONAUTICAL ENGINEERING - NASA Technical Reports Server  

Science.gov (United States)

corrosi6n bajo tensiones en las aleaciones de aluminio empleadas ei aircraft are discussed, giving attention to engine problems, hydraulic ...

3

Identification of source and recharge zones in an aquifer system from water stable isotope. Case Study Bajo Cauca Antioqueno  

International Nuclear Information System (INIS)

Hydrology and hydrogeochemical are auxiliary techniques to valid conceptual hydrogeology an recharge models. Stable isotopes from water trace sources and path flow and Tritium indicates age. This paper is about the use of D 18, D2H y 3H to study the aquifer system on Bajo Cauca antioqueno.

4

Production of three vector bosons in {gamma} {gamma} colliders; Producao de tres bosons vetoriais em {gamma} {gamma} colliders  

Energy Technology Data Exchange (ETDEWEB)

The production of three vector bosons in {gamma} {gamma} collisions studying the reactions {gamma} + {gamma} {yields} W{sup +} + W{sup -} + Z{sup 0} and {gamma} + {gamma} {yields} W{sup +} + W{sup -} + {gamma}. 12 refs., 4 figs., 2 tabs.

1994-12-31

5

Very high voltage cables with synthesis insulation; Les cables tres haute tension a isolation synthetique  

Energy Technology Data Exchange (ETDEWEB)

A historical review on insulated cables for power transmission, is presented, beginning with impregnated paper insulation, oil filled cables and natural rubber cables. High density and chemically reticulated polyethylene were then used for high voltage and very high voltage cables; the advantages of polyethylene compared to impregnated paper cables are discussed, which led to research programs at EDF on various themes concerning the optimization of polyethylene cables: dielectric properties and reliability, thermomechanical behaviour, thermal ageing of materials, testing methods (acceptance dielectric test and long duration temperature test); utilization of low- and high-density and chemically reticulated polyethylene for 225 kV cables is discussed

1997-06-01

6

State of the art in installation of buried HV and EHV cables; Etat de l'art sur la pose des cables souterrains a haute et tres haute tension  

Energy Technology Data Exchange (ETDEWEB)

CIGRE has set up a new working group - Insulated High Voltage Cables - under the auspices of Study Group 21. The working group will examine the various techniques used for the installation of HV and EHV cables and the design parameters to be applied. Twelve installation techniques are known, but only three of these ar used at present. Following an international study carried out by the working group, a clear picture of the state of the art in 1998 has emerged. It has also been possible to identify future trends in the design of buried circuits. (authors)

2000-05-01

7

Aspects of the carbon activated production since three Pinus species; Aspectos da producao de carvao ativado a partir de tres especies de pinus SPP  

Energy Technology Data Exchange (ETDEWEB)

Activated charcoal was produced from sawdust of Pinus caribaea var. caribaea, pinus caribaea var. honduenais and pinus cocarpa, with the objective of studying a alternative of more economic uses for forest residues and the products of the first thinning. A chemical process was utilized based on Zn Cl{sub 2} at temperature of 700 deg C and 450 deg C. It was concluded that the temperature of 700 Celsius produced a activated charcoal with better quality and greater adsorption capacity. The temperature of 450 deg C produced a material with adsorption properties for utilization where greater adsorption capacity is not needed. The production of activated charcoal is possible from the three species of tropical pinus studied. (author). 16 refs., 5 tabs

1987-12-31

8

Fifteen years of seismic monitoring at the Las Tres Virgenes, BCS, geothermal field; Quince anos de monitoreo sismico en el campo geotermico de Las Tres Virgenes, BCS  

Energy Technology Data Exchange (ETDEWEB)

Seismic monitoring at the Las Tres Virgenes, BCS, geothermal field started in 1992 with an analog station of vertical components detecting a large number of earthquakes of varying magnitudes. In February 1993, a seismic network was installed, composed of six digital stations DR-2000-with S-6000 and S-5000 sensors and three registration channels (N-S, E-W and vertical). This was the basis for the development of a program to correct arrival-time data for P and S waves due to instrument drift. From January to April 1994 and May to August 1995, based on the 170 seismic events recorded, a velocity model was proposed. From December 1995 to July 1996, seismic data were processed and interpreted, and zones of occurrence were determined for events according to magnitude and the predominant noise in the field. From September 2003 to December 2004, 10 seismic stations (permanent and temporary) were installed and monitored and it was concluded the most active fault system was ...

2009-07-15

9

Ionospheric response to the phenomena occurring below and above it: a summary  

Energy Technology Data Exchange (ETDEWEB)

Some of well known F{sub 2} layer anomalies might have their origin in lower atmosphere and some have extra terrestrial sources. It has been suggested that the phenomena occurring below the ionosphere such as thunderstorms, lightning/sprites, volcanic eruptions and earthquakes and above the phenomena like corona mass ejection, solar flares and extra terrestrial events may produce F{sub 2} layer signatures. In the present paper we have tried to summarize the effect of some phenomena occurring below the ionosphere like thunderstorms, lightning/sprites and seismic activity and the phenomena such as solar flares which occur above the ionosphere, on the ionospheric electron and ion temperatures. The paper also discusses possibilities. The ionospheric electron and ion temperatures were measured by the RrPAa payload aboard the Iindian SRrOSS-C2 satellite. The normal day's ion and electron temperatures have been compared to the temperatures recorded during the disturbed day. The ...

2009-01-15

10

Self-construction of a solar water heater; Calentador solar de agua de auto-construccion  

Energy Technology Data Exchange (ETDEWEB)

In this work a flat receiver of self construction is shown with relatively low cost and easy manufacture, but with a thermal efficiency superior to 40% for applications at temperatures less than 60 degrees Celsius, that allows satisfying international standards in this respect. The heater has been matter of study in open courses distributed in the Universidad Autonoma de la Ciudad de Mexico (UACM) oriented to that the participants construct their own system, in addition to its installation and tests. The obtained results have been excellent. The massive use of efficient solar receivers of self-construction can truly help to the decreasing of the gas discharges of greenhouse effect. [Spanish] En este trabajo se presenta un captador plano de auto construccion con relativamente bajo costo y facil manufactura, pero con un rendimiento termico superior a 40% para aplicaciones a temperatura menos de 60 grados centigrados que le permite satisfacer estandares ...

2009-07-01

11

Very low-dose hyper-radiosensitivity: impact for radiotherapy of micrometastases; Hyperradiosensibilite aux tres faibles doses: impact en radiotherapie des micrometastases  

Energy Technology Data Exchange (ETDEWEB)

Radio-biologists have pointed out a novel radiobiological phenomenon observed in many tumor and normal cell lines: hyper-radiosensitivity to very low-dose (H.R.S.) followed by induced radioresistance (I.R.R.) after a threshold dose of 0.1-0.3 Gy that depends on the cell line. Radioresistance at high dose (i.e. higher than 0.5 Gy) and metastatic potential of tumor cells are likely major factors of failure in radiotherapy. A careful review of literature suggests that: 1) radiotherapy does not increase the metastatic potential of tumor cells; 2) radioresistance at high dose and metastatic potential are not related. However, inside a given tumor cell line, highly metastatic clones may elicit more cells showing H.R.S; or are more radiosensitive at high dose than poorly metastatic ones. Recent data obtained from molecular techniques (comet and immunofluorescence assays) applied to single cells irradiated at very low radiation doses (1-100 mGy) suggest that DNA single-strand breaks (S.S.B.) ...

2007-09-15

12

Subsidence monitoring in the Cerro Prieto geothermal field, B.C., Mexico; Monitoreo de la subsidencia en el campo geotermico de Cerro Prieto, B.C., Mexico  

Energy Technology Data Exchange (ETDEWEB)

Since 1977, precise leveling surveys have been carried out to determine whether there have been vertical terrain displacements and the subsidence speed rate in the Cerro Prieto Geothermal field area. The elevation contours for each leveling show since 1962 that there was a basin that involves the geothermal field. The differences in the last three levelings show a generalized subsidence between Cerro Prieto (BN 10049) and Imperial faults (BN CD-14). [Spanish] A partir de 1977 se realizan trabajos de nivelacion de precision, con el fin de conocer si existen desplazamientos verticales del terreno y cual es la velocidad de subsidencia que existe en el area del Campo Geotermico de Cerro Prieto. Las configuraciones de cotas para cada uno de los anos nivelados, muestran que desde 1962 existe una cuenca que incluye al campo geotermico; la diferencia de cotas obtenidas en las tres ultimas nivelaciones, indican una subsidencia generalizada entre la Falla Cerro Prieto (BN ...

1999-04-01

13

Voltage and reactive power control by means of static compensators of vars in electric power systems; Control de voltaje y potencia reactiva mediante compensadores estaticos de Vars en sistemas electricos de potencia  

Energy Technology Data Exchange (ETDEWEB)

In this thesis a study is made of the of voltage characteristics and reactive power control in the transmission network of the Electric Power Systems (EPS) with static compensators of VARs (SCVs). The necessity of voltage and reactive power control and the application of SCVs as a solution means for three representative operation stages of the EPS, considering balanced operation conditions and fundamental frequency is analyzed: Operation in the presence of incremental voltage changes, quasi-stationary operation or steady state and behavior at the occurrence of big disturbances. The application of SCVs to systems of integral transmission is in general a closed loop control system, reason why the analysis of the interaction of the system EPS-SCV is considered as an essential part of the voltage and reactive power control study. Firstly, the response analysis of the control loop is made for incremental voltage changes, representing the power system by means of its equivalent of Thevenin ...

1987-07-01