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First assessment of low- to medium-temperature geothermal reserves in 20 Mexican states; Primera estimacion de las reservas geotermicas de temperatura intermedia a baja en veinte estados de Mexico  

Energy Technology Data Exchange (ETDEWEB)

A first, partial, assessment is included of the low- to medium-temperature geothermal reserves in 20 Mexican States and their aggregate value. The assessment covers about 29.16% of the identified geothermal-surface manifestations in the public database. For reserve assessments, we use the volumetric method, supplemented with Montecarlo simulations and statistics, to quantify inherent uncertainties. Our estimations are presented on a state-by-state basis. We estimate the aggregated reserves of the 20 states as between 7.7 x 1016 and 8.6 x 1016 kJ, with 90% confidence. The most likely reservoir temperatures range between 60-180 degrees Celsius, with a mean of 111 degrees Celsius. Such massive amounts of recoverable energy-and the associated temperatures-are potentially important for the economic development of nearby localities and the nation. [Spanish] En este trabajo se hace una primera estimacion, parcial, de las reservas geotermicas de temperatura intermedia a ...

2009-07-15

2

Spatial Variability of Wave Data from Todos Santos Bay, Baja California, Mexico  

Science.gov (United States)

... and operation of marine structures and to estimate coastal sediment transport. While the timely collection and report of high ... ...

3

DEFORESTATION - Earth from Space - Search Results  

Science.gov (United States)

Features: FOREST, DEFORESTATION, RIO JAMARI Geographic Region: BRAZIL .... Features: DEFORESTATION, TIERRAS BAJAS DEFORESTATION Geographic Region: BOLIVIA ...

4

Structure and Composition of the Polychaete Community from Bahia San Quintin, Pacific Coast of Baja California, Mexico  

Science.gov (United States)

... poly-chaete densities and diversity values, probably the oyster aquaculture in BF although not intensive has produced a ... faster (Díaz-Castañeda & Rodriguez-Villanueva 1998). However if oyster aquacultu...

5

Local wind patterns for modelling renewable energy systems by means of cluster analysis techniques  

Energy Technology Data Exchange (ETDEWEB)

A method based on cluster analysis techniques is proposed in order to obtain representative local wind patterns. Modeling renewable energy systems, in an accurate way which strongly depends on wind loads, requires reliable data to analyze their response and evaluate their performance. Otherwise poor agreement with the models may be obtained. In a case study for La Paz, Baja California Sur, Mexico, four different wind patterns were obtained from a one-year data set recorded at 10-min intervals. (author)

2002-02-01

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Modern carbonate sediments and environments of the LaPaz region, Baja California Sur, Mexico  

Energy Technology Data Exchange (ETDEWEB)

The Gulf of California represents one of the most productive and unique marginal seas in the world. The mouth of the Gulf captures warm equatorial water while annual wind patterns assure major upwelling of nutrient-rich water leading to a rich marine biota. These conditions have created a wide array of tropical through warm temperate carbonate environments. The most unusual of these environments is located in the La Paz region of Baja California Sur where tropical-subtropical water temperatures and low rainfall have allowed growth of corals, calcareous red algae, and other shelled invertebrates to form a carbonate bank environment. Sampling and mapping transacts in shallow bays north of La Paz and on the adjacent Espiritu Santo island have revealed a full spectrum of subenvironments including mangrove bordered, terrigenous mud dominated coastal zones, which grade into carbonate tidal flats. In addition, single coral heads as well as incipient reef structures ...

1996-12-31

7

Ruthenium-106 brachytherapy for uveal melanomas. Preliminary results: a single institutional experience; Braquiterapia com rutenio-106 em melanomas uveais. Resultados preliminares: experiencia uni-instuticional  

Energy Technology Data Exchange (ETDEWEB)

Objective: To analyze the early response of uveal melanomas in patients treated with ruthenium-106 brachytherapy. Materials And Methods: In the period between April 2002 and July 2003, 20 patients diagnosed with uveal melanoma were submitted to ruthenium-106 brachytherapy. The calculated dose delivered at the apex of the tumor ranged between 55 Gy and 100 Gy. Patients with lesions greater than 5 mm were submitted to transpupillary thermotherapy concomitantly with ophthalmic plaque insertion. Results: As regards the lesions site, 75% of the lesions were located in the choroid, 15% in the iris, and the remainder 10% in the ciliary body. In a median 19-month-follow-up, the progression-free survival for brachytherapy was 69%, and 87% for associated brachytherapy and transpupillary thermotherapy. A significant tumor height reduction was observed after treatment. No patient was submitted to enucleation. Conclusion: Our preliminary results show that ruthenium-106 brachytherapy is an ...

2007-03-15

8

Results of the Interlaboratory Exercise CSN/CIEMAT-100 Among Environmental Radioactivity Laboratories (Soil); Resultados del Ejercicio Interlaboratorios de Radiactividad Ambiental CSN/CIEMAT-00 (Suelo)  

Energy Technology Data Exchange (ETDEWEB)

The document describes the outcome of the CSN/CIEMAT-00 interlaboratory test comparison among environmental radioactivity laboratories. the exercise was organised according to the ISO-43 and the ISO/IUPAC/AOAC Harmonized Protocol for the proficiency testing of analytical laboratories. the test sample was a soil containing environmental levels of K-40, Ra-226, Ac-228, Sr-90, Cs-137, Cs-134, Pu (239-240) y Am-241. the Universidad Autonoma de Barcelona prepared the material and reported adequate statistical studies of homogeneity. The results of the exercise were computed for 30 participating laboratories, and their analytical performance was assessed using the u-score approach. A raised percentage of satisfactory laboratory performance has been obtained for all the analysis, being the best performance in gamma measurements. The exercise has drawn that several laboratories have difficulties in the evaluation of combined uncertainty, mainly in analysis involving radiochemical steps. The ...

2002-07-01

9

Importance of Recognizing Occult Renal Disease in Hypertensive Patients  

British Library Electronic Table of Contents (United Kingdom)

Introduccion y objetivos La enfermedad renal oculta (ERO) es una entidad que define los estadios mas iniciales de insuficiencia renal y no se detecta con los metodos usados habitualmente. El objetivo es determinar la prevalencia de ERO en los pacientes hipertensos en consultas de cardiologia y su relacion con los distintos factores de riesgo y tratamientos cardiovasculares. Metodos. Estudio observacional, transversal, retrospectivo y multicentrico que se llevo a cabo en 1.214 hipertensos de consultas de cardiologia. Resultados . Se analizo a 1.190 pacientes (98%). El filtrado glomerular (FG) fue calculado (MDRD) por el cardiologo responsable en el 11% de los pacientes. Tras su determinacion a posteriori, el 9,5% presentaba ERO, mas probablemente mujeres, con mas edad, mas antecedents de di...

2009-01-01

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 internacionales a este respecto. El ...

2009-07-01

11

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

12

Heat transfer equipment performance diagnosis of auxiliary systems in electric power stations; Diagnostico de comportamiento de equipo de transferencia de calor de sistemas auxiliares de centrales termoelectricas  

Energy Technology Data Exchange (ETDEWEB)

In this article the methodology followed to diagnose the performance of the equipment where heat is transferred from the feed water, condensate and circulation water systems in fossil power plants (FPP). The data collection is made with the unit in normal operation, using local instrumentation without taking the equipment out of service for its installation. The equipment diagnosis is made through the analysis of the collected data in actual operation and the design data; for this purpose a thermal balance of the interested systems is performed to obtain all the conditions an operation data. Later on the performance indicative parameters (PIP) of actual operation and design are calculated and compared one against the other. Such a comparison reveals the performance deterioration and the possible equipment faults. The data obtained and the supplementary information are stored in a data base whose objective is that Comision Federal de Electricidad has on hand a prompt access to them in ...

1990-12-31

13

New technology for the emulsification of petroleum residuals in water; Nueva tecnologia para la emulsificacion de residuales del petroleo en agua  

Energy Technology Data Exchange (ETDEWEB)

It turns out of interest to Comision Federal de Electricidad and Petroleos Mexicanos to reduce costs of fuel oil, reducing the viscosity of the residues petroleum of high vacuum distillation emulsifying these with water. The parameters that define the characteristics of the emulsions are mainly the relation of their components, viscosity, size and drop distribution and its stability. The experimental work began producing emulsions in form of lots, using samples of approximately 500 milliliters of vacuum residue. In this first stage, at different concentrations, were examined eight different surfactants, as well as combinations among them, also seven different stabilizers were used. With these tests it has been managed to identify the concentrations, as well as the most adequate relations of surfactants and stabilizers for the production of emulsions of vacuum residues in water. The size and drop distribution has been determined by means of an optical LEICA microscope, model DMLS, that ...

2001-07-01