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Ramirez-Camperos A.M.,National Autonomous University of Mexico | Rodriguez-Padilla V.,National Autonomous University of Mexico | Guido-Aldana P.A.,Instituto Mexicano Of Tecnologia Del Agua Imta
Energy Policy | Year: 2013

This article analyses the cause-effect relation of the structural reform in the Mexican electricity sector, called the Public Electricity Service Act, from 1992 to 2009. One of the main arguments of the reform is to attract private investment in order to reduce the financial load of the government in infrastructure for the development of the National Electric Power System by means of six modalities (Power Self-Supply, Cogeneration, Small Power Production, Independent Power Production, Power Export and Power Import). The article presents the global context of reforms adopted in 1990. The major policies and events are presented in chronological order (before and after reform). In addition, it analyses the new institutional framework, the evolution of modalities, technologies of electricity generation and tariffs. The main conclusion is that the result of reform could be considered a partial progress. The Independent Power Production modality shows greater participation, while Power Self-Supply and Cogeneration are lower. The subsidy policy is maintained. Progress is needed in policies and strengthening, and also in updating regulatory and normative frameworks. © 2013 Elsevier Ltd.

Hansen A.M.,Instituto Mexicano Of Tecnologia Del Agua Imta | Gay D.A.,University of Illinois at Urbana - Champaign
Environmental Science and Pollution Research | Year: 2013

We provide a longer-term record of Hg wet deposition at two tropical latitude monitoring sites in Mexico, selected to provide regionally representative data. Weekly wet deposition samples were collected over 2 years, from September 2003 to November 2005. Based on this data set, we discuss the magnitude and seasonal variation of Hg in wet deposition and compare the results to other measurement sites and to several model estimates. With precipitation-weighted mean (PWM) concentrations of 8.2 and 7.9 ng L-1, respectively, during the sampling period from Sep 30 2003 to Oct 11 2005, and median weekly concentrations of 9.4 ± 1 ng L-1 for both sites, the wet Hg concentrations and deposition at HD01 were much lower than those observed at the US Gulf Coast MDN sites while the wet Hg deposition at OA02 was much lower than most MDN sites, but somewhat similar to US MDN sites along the Pacific Coast. Based on the limited available data, we conclude that the approximately 30 % higher average precipitation at HD01 and roughly equal PWM concentrations lead to the higher deposition at HD01 versus OA02. We believe that these observations may offer scientists and modelers additional understanding of the depositional fluxes in the lower latitudes of North America. © 2013 Springer-Verlag Berlin Heidelberg.

Soares D.,Instituto Mexicano Of Tecnologia Del Agua Imta | Murillo-Licea D.,Research Center y Estudios Superiores en Antropologia Social
Cuadernos de Desarrollo Rural | Year: 2013

The aim of this paper is to contribute to the reflection on the link between disaster risk management and gender equity. It is presented a case study on perceptions about climate change and institutional abilities regarding risk management in four locations of the state of Yucatan, Mexico. In order to know the local social perceptions, surveys and interviews were administered to key informants, and the results account for the existence of serious problems in municipal institutions in charge of both disaster risk management and the promotion of processes to generate greater gender equality. Additionally, a lack of knowledge about the factors that cause climate change was recorded.

Wolaver B.D.,University of Texas at Austin | Crossey L.J.,University of New Mexico | Karlstrom K.E.,University of New Mexico | Banner J.L.,University of Texas at Austin | And 3 more authors.
Geosphere | Year: 2013

He, C, and Sr isotopes are used to infer spring sources in a water-stressed area. Spring-water origins and pathways in the Cuatrociénegas Basin are revealed by linking structure and geochemistry via regionally extensive fault networks. This study presents the first dissolved noble gas and He isotopic data from northeastern Mexico. Basementinvolved faults with complex reactivation histories are important in northeastern Mexico tectonics and affect hydrogeologic systems. The importance of faults as conduits for northeastern Mexico volcanism is recognized, but connections between faulting and the hydrogeologic system have not been extensively investigated. This research tests the hypothesis that Cuatrociénegas Basin springs are divided into two general classes based upon discharge properties: (1) regional carbonate aquifer discharge (mesogenic) mixed with contributions from deeply sourced (endogenic) fluids containing 3He and CO2 from the mantle that ascend along basement-involved faults; and (2) carbonate aquifer discharge mixed with locally recharged (epigenic) mountain precipi tation. Carbonate and/or evaporite dissolution is indicated by Ca-SO4 hydrochemical facies. He isotopes range from 0.89 to 1.85 RA (RA is the 3He/4He of air, 1.4 × 10-6) and have minimal 3H, from which it is inferred that basement-involved faults permit degassing of mantle-derived He (to 23% of the total He) and CO2 (pCO2 10-1 atm). Mantle degassing is compatible with the thinned North American lithosphere, as shown in tomographic images. Sr isotopes in both Cuatrociénegas Basin springs and spring-deposited travertine (87Sr/86Sr = 0.707428-0.707468) indicate that carbonate rocks of the regional Cupido aquifer (87Sr/86Sr = 0.7072-0.7076) are the main source of Sr. Rock-water interactions with mafic volcanic rocks (87Sr/86Sr = 0.70333-0.70359) are not inferred to be an important process. Groundwater-dissolved inorganic C origins are modeled using major elements and C isotopes. C isotope data show that ~30% ± 22% of CO2 in spring water is derived from dissolution of aquifer carbonates (Ccarb = 30%), 24% ± 16% is from soil gas and other organic sources (Corg = 24%), and 46% ± 33% is from deep sources [Cendo (endogenic crust and mantle) = 46%]. This study demonstrates the presence of mantlederived 3He and deeply sourced CO2 that ascend along basement-penetrating faults and mix with Cupido aquifer groundwater before discharging in Cuatrociénegas Basin springs. © 2013 Geological Society of America.

Robles I.,Instituto Mexicano Of Tecnologia Del Agua Imta | Palacio A.,National Autonomous University of Mexico | Rodriguez A.,National Autonomous University of Mexico
Dam Protections against Overtopping and Accidental Leakage - Proceedings of the 1st International Seminar on Dam Protections Against Overtopping and Accidental Leakage | Year: 2015

In this paper the design of a structure to dissipate energy in the spillways was analyzed as an alternative to reduce the destructive effects of water at high speed. Work on energy dissipation are critical elements in the construction of hydraulic structures, these have been developed based on the experience and wealth of knowledge in the field, however, the design of these structures involves laboratory studies, collection prototype field data, statistics, among others. In order to assist in this effort to collect information useful in the design of structures of energy dissipation information current work is presented with information obtained from laboratory data relevant parameters of structures including willing obstacles especially to achieve this objective. The main objective of the study is to have design elements to build a structure of energy dissipation decreases the undesirable effects present in the spillways flow with a sufficiently quieted to avoid structural damage. This was done with the support of a laboratory physical model provided for this purpose. For testing of the physical model α angle was set in one position and the following dimensionless parameters were varied: Lh/Lv, d/D, where D is the maximum diameter of the tests performed. Also the velocity profiles of all testswere measured at 0.12mfrom the point of supply to the water structure in the physical scale model. There are evidences that the variable that dominates the energy dissipation in these structures is the change in diameter of the cylindrical obstructions. © 2015 Taylor & Francis Group, London.

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