Nuclear pulse generator embedded in FPGA.

This manuscript presents the design and implementation of an intellectual property core, which acts as a generator of nuclear pulses. The design is embedded in a Field programmable gate array. It is capable of forming pulses with an exponential shape such as those from a radiation detector or Gaussian-shaped pulses such as those provided by a spectroscopy amplifier. Its characteristic is that the amplitude and period of these pulses can be configured by the user through a Virtual instrument generated in graphic language through the LabVIEW development platform. This can greatly reduce the volume, cost and energy consumption in relation to commercial analog nuclear electronics pulse generators.

FPGA embedded multichannel analyzer.

An multichannel analyzer has been designed, and its performance has been evaluated. The multichannel analyzer is embedded into a Field programmable gate array. The design incudes the virtual instrument in order to hand and to visualize the pulse height spectrum. Two commercially available multichannel analyzers using a NaI(Tl) and HPGe detectors were used to obtain the pulse height spectra of 137Cs, 60Co and 152Eu sources and were compared with the pulse height spectra obtained with the embedded multichannel analyzer, being alike the spectra obtained with the commercial multichannel analyzer. Our design is smaller, low cost and it has options to add other features.

[Lead levels in high-risk populations and the surrounding environment in San Ignacio, Fresnillo, Zacatecas, México]. / Niveles de plomo en la población de alto riesgo y su entorno en San Ignacio, Fresnillo, Zacatecas, México.

OBJECTIVE: To determine the lead concentration in the blood of children and nursing or pregnant women from San Ignacio, Fresnillo, in Zacatecas, Mexico as well as in soil, plants, ash and lead-glazed pottery, in order to determine exposure due to a metal-recycling facility. MATERIAL AND METHODS: The study was carried out from December 2004 to April 2005. Lead in blood was measured with anodic stripping voltammetry, while dispersive energy X-ray fluorescence was used in the other matrices. RESULTS: Based upon the criteria outlined in the Official Mexican Standards, 90% of the children was identified as category 1, 5% as category II and another 5% as category III. The soil in the land near the facility contained from 73 to 84,238 microg/g, with an average of 4940 microg/g. Larger lead concentrations were found on sites located closer to the facility. San Ignacio's soil contained, on average, 109 microg/g. High lead levels were found in glazed pottery and the concentration in agricultural crops was greater than 300 microg/g. CONCLUSIONS: Although the majority of children in San Ignacio have blood lead concentrations considered to be acceptable according to the Official Mexican Standards, several studies indicate that deleterious effects on children's health exist even at low concentrations. The land around the metal recycling facility is contaminated with lead, and to that extent, the crops that are produced there, once ingested, are a source of contamination, which is compounded by the use of glazed pottery.

Niveles de plomo en la población de alto riesgo y su entorno en San Ignacio, Fresnillo, Zacatecas, México / Lead levels in high-risk populations and the surrounding environment in San Ignacio, Fresnillo, Zacatecas, México

OBJETIVO: Determinar la concentración de plomo en la sangre de niños y mujeres, en periodo de lactancia o embarazadas, de la comunidad de San Ignacio, Fresnillo, en Zacatecas, así como en matrices de suelo, plantas, ceniza y barro vidriado, para determinar la exposición que genera una empresa recicladora de metales. MATERIAL Y MÉTODOS: El estudio se realizó de diciembre de 2004 al mes de abril de 2005. El Pb en sangre se midió por voltamperometría de redisolución anódica, mientras que se utilizó energía dispersa de fluorescencia por rayos X para las otras matrices. RESULTADOS: Con base en los criterios de la Norma Oficial Mexicana (NOM) se encontró que 90 por ciento de los menores está en la categoría I, 5 por ciento se encuentra en la categoría II y el otro 5 por ciento se ubica en la categoría III. El suelo de los terrenos aledaños a la recicladora tiene en promedio 4 940 µg/g, en un intervalo de 73 a 84 238 µg/g. Las mayores concentraciones se localizan en los puntos más cercanos a la empresa. El suelo de San Ignacio tiene en promedio 109 µg/g. Se encontraron valores altos en el barro vidriado y la concentración del Pb en las plantas es superior a los 300 µg/g. CONCLUSIONES: A pesar de que la mayoría de los niños analizados presenta niveles de plomo en sangre que la Norma Mexicana señala como aceptables, varios estudios indican que existen efectos nocivos aun a concentraciones bajas. Los terrenos aledaños a la empresa están contaminados, y en esa medida los alimentos que ahí se producen, al ser consumidos, son una fuente de contaminación, que se agudiza con el uso de barro vidriado.