[en] In this work the results of the analysis are presented, using the PIXE technique (Proton Induced X-ray Emission), in soil samples of the El Bordo, Vetagrande, Zacatecas, before and after subjecting them to a lixiviation process for the recovering of gold, silver and mercury. This community is part of the mining region nearer to the Zacatecas city municipality, region in which the mining exploitation dates from the colonial time. During almost 350 years the 'yard benefit' method was used or amalgamation with mercury, process that besides having used big quantities of mercury, generated a great quantity of mineral waste calls 'mine wetlands', those that were accumulating, crawled by the rains, toward the streams that end in the prey 'The Pedernalillo'. The dispersion of wetlands them it has extended from the prey until the communities of Tacoaleche, Zoquite, Lampotal and El Bordo, embracing an approximate area of 16 x 2 Km² and forming with the course of the time an accumulated of several millions of tons. In order to determining if the process of recovery of gold, silver and mercury make soluble to other contained metals in these wastes, samples were gathered in an area of 600 m² in the community of The Border, Vetagrande, Zacatecas. Half of the samples were subjected to the lixiviation process in a local metal recovery plant and the other part was analyzed without processing. The analysis of both types of samples by means of the PIXE was carried out in the University of Arizona in Tucson. (Author)

[en] In this work, the results obtained in the determination of the spectra of energy fluence, the radiation doses and the dose equivalents produced by a source of Californium 252 located in a spectrometric system based in the Bonner spheres and with the help of a computer program named BunkiUT are presented. (Author)

No abstract available

[en] Knowledge of environmental radiation is essential to establish the environment quality. Through in situ gamma spectrometry is possible to determine the existence of gamma emitters (natural and artificial) distributed in soils; the natural gamma radiation spectra are made up of several photo-peaks, and in the case of the natural radioactive series, it allows the determination of the ²³⁸U and ²³²Th progenitors, in the case of ¹³⁷Cs and ⁴⁰K are determined directly with its characteristic energies. This is done with the purpose of knowing the gamma emitters present in the soil, in addition to making an evaluation of possible radiological risks. The results of this work have been evaluated and validated with those reported in the literature. An inadequate statistic or an inappropriate choice of spectrum manipulation parameters reduces the quality of the results obtained by the gamma spectrometry system, so it is important to establish appropriate methodologies and factors for editing and conversion. Measurements were made in situ and samples were taken for laboratory measurements in the localities of Tabasco, Loreto, Pinos and Fresnillo of Zacatecas State (Mexico). Sampling was done to determine the profile of activities up to a depth of 25 cm. Gamma spectra were acquired with a spectrometric system based on a germanium crystal. On-site measurements showed consistency with laboratory measurements. The specific activity determined of the radio-nuclides under study is in the order of the values reported in the literature and the risk factors found are in the order of the values of the normal levels. The presence of ¹³⁷Cs was determined in some spectra in situ, confirmed by those determined in the laboratory. (Author)

[en] The radiotherapy is the use of the ionizing radiations for treatment of several cancer types. The radiotherapy equipment s are situated inside an installation specially designed to offer attention to the patients and appropriate radiological protection of the occupational exposed personnel and the public in general. For this reason is necessary to evaluate the behavior of the shielding of the radiotherapy room of the Instituto Zacatecano del Tumor located in the Zacatecas city. Accumulated dose measurements were made in a work day of the radiotherapy room in the interest points using solid state dosimeters, considering the number of attended patients, the applied treatments and the discharges number. Also the simulation of the radiation gamma transport in the room was realized by means of Monte Carlo method with the MCNP5 code to compare the results. In the measurement points of the exterior of room the doses are practically similar to those of the bottom of natural radiation, what means that the shielding of the room is fulfilling its function. In the measurement points located inside the room we find higher dose and with more risk for the health. It is important to carry out this type of studies to guarantee the radiological protection of the occupational exposed personnel and the public in general. With these studies we can establish that so much is possible to increase or to reduce the work load in a radiotherapy room. (Author)

[en] The environmental radioactivity evaluation is a key point in the assessment of the environmental quality. Through this, it can be found possible radioactive contamination, locate possible Uranium and Thorium deposits and evaluate the primordial isotopes concentration due to human activities. A radioactive map of the Zacatecas State, Mexico is under construction based on in situ gamma-ray spectrometry. The present work reports the results of the multivariate statistical approximation of the measured activity data. Based on Pearson correlation, the ²²⁸Ac and ²⁰⁸Tl activities are statistically significant, while the ²¹⁴Bi and ²¹⁴Pb activities are not statistically significant. These can be due to the existence or not of secular equilibrium in the Thorium and Uranium series. (Author)

[en] The ²²⁶ Ra is one of the more radio toxic nuclides since when entering to the organism it continues metabolically to the calcium, accumulating mainly in the bone tissue where it becomes in an internal radiation source. For the analysis of radium in water the methods of radon emanation are generally applied and coprecipitation with barium sulfate. This last is quick and efficient, and the radium in the precipitate can be measured by alpha or gamma spectrometry, or liquid scintillation dissolving the precipitate one with EDTA. In this work it is proposed a procedure for the radium measurement in water based on the coprecipitation with barium sulfate and in the detection by liquid scintillation. The precipitate of Ba(Ra)SO₄ it is carried with water and blended with the liquid scintillator OptiPhase Hi Safe 3, avoiding the dissolution with EDTA. A 92± 1.4% of radium it was recovered and it was reached a minimum activity detectable of 4.2 ± 0.9 mBq^-1. The procedure was essayed with natural mineral water with a knew activity in concentration of ²²⁶ Ra. The analytic result it coincided with the reported value with a relative error of 9%. (Author)

[en] The uranium determination through radiometric techniques as alpha spectrometry requires for its proper analysis, preparation methods of the source to analyze and procedures for the deposit of this on a surface or substrate. Given the characteristics of alpha particles (small penetration distance and great loss of energy during their journey or its interaction with the matter), is important to ensure that the prepared sources are thin, to avoid problems of self-absorption. The routine methods used for this are the cathodic electro deposition and the direct evaporation, among others. In this paper the use of technique of chemical vapor deposition (CVD) for the preparation of uranium sources is investigated; because by this, is possible to obtain thin films (much thinner than those resulting from electro deposition or evaporation) on a substrate and comprises reacting a precursor with a gas, which in turn serves as a carrier of the reaction products to achieve deposition. Preliminary results of the chemical vapor deposition of uranium are presented, synthesizing and using as precursor molecule the uranyl acetylacetonate, using oxygen as carrier gas for the deposition reaction on a glass substrate. The uranium films obtained were found suitable for alpha spectrometry. The variables taken into account were the precursor sublimation temperatures and deposition temperature, the reaction time and the type and flow of carrier gas. Of the investigated conditions, two depositions with encouraging results that can serve as reference for further work to improve the technique presented here were selected. Alpha spectra obtained for these depositions and the characterization of the representative samples by scanning electron microscopy and X-ray diffraction are also presented. (Author)

[en] The radiation and natural radioactivity is present in the man's food chain, like it is the case of the milk, and it comes from the natural series of radioactive decay of the ²³⁸ U, ²³⁵ U and ²³² Th, and of the ⁴⁰ K radioisotope. Since the radioisotopes can be found in floor of where its are transferred to the grasses and in the water that serve as food and of drinking to the cows, then to enter the milk and its derived to the human consumption. In this work it is presented the study of the radiation and gamma radioactivity of 40 samples of dairy formulas of the trademarks and presentations more sold in the market of the private and public sectors. The measurements of the gamma ray spectra were carried out with a spectrometry system based on an Hyper pure Germanium detector (HPGe). The detector has a resolution (FWHM) of 1.9 keV for an energy of the gamma ray of 1.332 keV of the ⁶⁰ Co. This study presents the results of the concentration in activity of dairy formulations of the radioisotopes of interest. Also, the results are related with possible damages to the health. (Author)

[en] Radioactivity of honey samples from 10 municipalities of the Zacatecas State in Mexico was investigated by gamma spectrometry. The honey corresponds to the prosopis laevigata flowering. The purpose of the study was to estimate the background levels of natural radioactivity and to discard a possible contamination with the artificial ¹³⁷Cs in honey. Any naturally occurring radionuclide could be determined except for ⁴⁰K, which was quantified in 8 of the 10 samples, with an average in specific activity of 9.75 ± 1.8 Bq/kg. No signal for the energy of the anthropogenic radionuclide ¹³⁷Cs was observed, corroborating that the radiation levels are in good agreement with those reported for another honeys in the world. (Author)