This research presents a study of environmental monitoring at different sampling sites from the Metropolitan Area of the Valley of Toluca (MAVT), Mexico, using mosses (Leskea angustata(Tayl.) andFabronia ciliaris(Brid.)) and soil samples. The epiphytic mosses and soils were sampled in two campaigns within two periods of the year, a rainy and dry-cold season. The selected sampling sites included urban regions (UR), transitional regions (TR), and protected natural areas (PA). The samples were analyzed by the Instrumental Neutron Activation Analysis (INAA) to determine As, Cr, Hg, and Se principally. However, due to the versatility of the analytic technique used, other elements including Cs, Co, Sc, Sb, Rb, Ce, La, Eu, and Yb were also detected. Statistical analysis (As, Cr, Hg, and Se) was carried out with principal components and cluster analysis methods; this revealed that a good correlation exists between metal content in mosses and the degree of pollution in the areas sampled. The obtained results in mosses showed that the concentrations of As, Cr, Co, Cs, Rb, Ce, La, and Yb increased with respect to the concentrations obtained during the first sampling, whereas Se, Sc, Sb and Eu, concentrations were decreased. For As and Hg, the concentrations were similar in both sampling periods. The soil samples present the most significant concentration.

This research presents the obtaining of a biochar (CB) from the use of pomegranate peel (Punica granatum) conditioned with iron and cerium nanoparticles (C-Fe/Ce), as well as its characterization by SEM (Scanning Electronic Microscopy), FTIR (Fourier Transform Infrared Spectrometry), TGA (Thermogravimetric analysis), EDS (Energy Dispersive Spectroscopy), XPS (X-Ray Photoelectron Spectroscopy) and evaluation of the adsorption capacity of ampicillin (AMP) in aqueous phase at 20, 30 and 40 C. The maximum adsorption capacity for CB was 18.97 mg g À1 and for C-Fe/Ce, 27.61 mg g À1 at pH of 7, observing that with increasing temperature, the sorption capacity decreases in both materials, the experimental data was fitted to various mathematical models and the best fit was the pseudo-second order model for the kinetics, whilst for the adsorption isotherms the best fit was with the Langmuir model, indicating that the adsorption process is carried out in a monolayer on a homogeneous surface, through a chemisorption process. According to the thermodynamic parameters this process is carried out through an exothermic reaction. The results obtained indicate that both materials are suitable for the removal of AMP in the aqueous phase and that they can be reused up to 5 times.

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The design and testing of a fuzzy rule based controller to regulate the power of a TRIGA Mark III research nuclear reactor are presented. The design does not require the current exact parameters of the point kinetic equations of the reactor. Instead, from a qualitative analysis of the actions taken by the operators during the reactor’s operation, a set of control rules is derived. The rules cover the operation of the reactor from low levels of about dozens of watts up to its full power level of one megawatt. The controller is able to increase power from different initial values to a wide range of desired levels, maintaining constant levels for long periods of time. The controller’s output is the external reactivity, which is further converted to a control rod incremental movement. The fuzzy controller is implemented on the reactor’s digital operating console, and the results of a series of experiments are discussed.