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A synthesis by plasma of polymers with structure of oxidized ethylene (PPEO) obtained from ethanol is presented in this work with the objective to obtain hydrophilic and potentially biodegradable PPEO films. The synthesis was carried with rf glow discharges in the 20–120 W interval obtaining films with a 0.38 μm/W growing rate thickness. Morphology, chemical structure, hydrophilicity and absorption of electromagnetic energy in the UV–visible interval were analyzed. The results indicated that PPEO has smooth surfaces with particles and/or folded areas with water contact angles between 72° and 97°, in the limit between hydrophilicity and hydrophobicity. The structural chemical analysis showed the presence of C–H and O–H bonds characteristic of the monomer, and C=O and ≈C≈ groups characteristics of plasma polymers with dehydrogenation and formation of multiple bonds. The absorption of electromagnetic energy of PPEO was more intense in the UV than in the visible wavelength interval. These characteristics indicate that PPEO can be biodegradable under the sunlight and/or under wet environments.

This research presents the obtaining of a biochar (CB) from the use of pomegranate peel (

There are many healthcare facilities in Spain that were built throughout the second half of the 20th century, and compose an interesting built heritage designed by outstanding architects of the architectural avant-garde. Some of them were included in the DOCOMOMO's list of buildings to be preserved and documented. As a consequence, every intervention on the hospitals' heritage requires a special attention and needs a deep knowledge of the building in advance of taking action. On the other hand, such a particular heritage is being continuously updated according to the new standards that derive from the current tendencies in hospital design, and also from advances in healing techniques. In this context, 3D Modelling and virtual reality should have a decisive impact on the way hospitals' complex spaces are designed, as they become useful tools for describing the previous stages of the buildings, as well as the impacts of new proposals. They can even change our experience of the built environment. As a step forward, we are developing a methodology to be applied to hospital design where these tools, together with BIM models -and in the near future, high-end immersive VR systems- play an important role., Ministerio de Economía y Competitividad

This work presents the formation of biochar with calcium nanoparticles (NPsCa) in function of pyrolysis time (C10, C30, C60, C120 and C180 min) using the Citrus tangerina peel and their evaluation in the remotion of Aflatoxin B1 (AFB1) in aqueous phase. Firstly, the Citrus tangerina was studied by Thermogravimetric analysis to determine the optimal temperature (TGA), obtaining a result of 600 °C. The biochar (NPsCa) were characterized by Scanning Electronic Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS), as well as surface properties including the identification of functional groups by Fourier Transform Infrared Spectrometry (FTIR), and energetic states through the X-Ray Photoelectron Spectroscopy (XPS). The adsorption studies were carried out on the different materials and later, the experimental data was adjusted to different mathematical models, obtaining the best fit of the kinetic data to the Ho-McKay model, whilst the adsorption isotherms were adjusted to the model of Langmuir, which indicates that the Aflatoxin B1 adsorption process is carried out through a monolayer chemisorption process with maximum sorption capacities (qm) ranging between 15.72 and 63.22 μg g-1 with the 180th minute being the adequate time to obtain the carbon with the best surface properties and the best adsorption capacity. Additionally, it was observed that each material can be reused up to five times in accordance with the results from the reuse cycles.

Several kinds of paper (Bond, Amate, Rice, Press, and Whatman#1) were studied in their original condition and were then exposed to gamma radiation between 3 and 15 kGy (0.9 kGy/h) with intervals of 3 kGy. The length and width of fibers (SEM) as well as pH were measured, and the chemical composition was determined by EDS. Pyrolysis characteristics (TGA and DTC), transmittance spectra by IR and X-ray diffraction patterns were studied as well. Whatman#1 contains only cellulose; whereas Bond, Press and Rice papers also contain calcite and Amate whewellite. All X-ray diffraction patterns showed Type I semicrystalline cellulose, but a slight presence of Type II was noted in the artisan papers (Amate and Rice). These results were confirmed by IR spectra and thermogravimetric analyses. Due to gamma irradiation no acidification nor change of fiber sizes or alteration of other studied parameters were observed. Therefore, these conditions may be recommended for the treatment of some deteriorated documents.

This research presents a study of environmental monitoring at different sampling sites from the Metropolitan Area of the Valley of Toluca (MAVT) Mexico by means of moss samples. The selected sampling sites included urban, transitional and natural protected areas. The mosses were obtained in two campaigns within two periods of the year: rainy-season and dry-cold-season. During the sampling, seven species of moss were identified, among them: Leskea angustata (Tayl.) and Fabronia ciliaris (Brid.) were the most abundant. One sample of each species was analyzed by SEM in order to determine their morphology. After that, the samples were analyzed by instrumental neutron activation analysis (INAA) and total X-ray fluorescence spectrometry (TXRFS) in order to determine the metals concentration. The results indicate that the Urban Region was significantly impacted by pollution compared to the natural protected Areas. The cluster statistical analysis results indicated that the sampling sites with the highest concentration of metals are located in the urban areas. Enrichment factors show that As, Cr, Cu, Zn, Pb, Se, Cs, and Sb are highly enriched mainly by anthropogenic sources.

Effective Fe-TiOx magnetic nanoparticles were synthesized on pineapple-peel (CPa-Fe/TiOx) to evaluate their As(V) uptake capacity. The nanocomposite was characterized by means of BET surface analysis, SEM, TEM, XRD, FTIR and XPS. The results indicated the obtention of spherical nanoparticles with 5.7 nm of diameter distributed on the surface of pineapple peel with a Ti:Fe molar ratio of 2:1, while DRX indicate that the material is amorphous. IR spectra of the obtained CPa-Fe/TiOx present a number of bands at 3316, 2924, 2852, 1729, 1632, 1371, 1241, 1035, 590 and 545, indicating the existence of hydroxyl and carboxyl groups on the composite material. The nanocomposite was evaluated as an adsorbent of As(V) and experimental parameters as time, pH, concentration and temperature were evaluated. CPa-Fe/TiOx were effective at pH = 5.5, sorption isotherms showed that sorption capacities of the Fe-TiOx, were dependent on the site density, surface area and temperature change. The equilibrium data was modelled with the help of Langmuir and Freundlich equations, based on the values of correlation coefficients (R2) the Langmuir isotherm equation was excellently fitted to the experimental data of the arsenic adsorption with a maximum adsorption uptake of 40 mg/g under the studied conditions. The thermodynamic results showed that the sorption of As(V) onto CPa-Fe/TiOx was feasible, spontaneous and exothermic, through mechanism ligand effect-surface, with the interaction between oxy-hydroxides of Fe and Ti with oxy-anions of arsenic present in solution.

The objective of this work was to synthesize particles of titanium oxide and cerium oxide supported on carbon, which was obtained through the pyrolysis of orange peel. The materials were characterized using scanning electron microscopy, X-ray diffraction, infrared spectroscopy, and the specific surface area from Brunauer-Emmett-Teller method. The photocatalytic properties of the synthesized materials were determined by the degradation of phenol in 30 mg/L aqueous solutions. TiO 2 -CeO 2 particles were obtained with an average spherical size of 57 nm and were supported on the carbon surface; this material presented a specific surface area of 296 m 2 /g and degrades ∼40% of phenol after 240 min of UV irradiation.

The degradation of methyl orange (MO) in presence of a natural zeolite from San Luis Potosi, Mexico, previously homo-ionized with Na cations (HNaZ) and impregnated with iron boride nanoparticles (HNaZ-Fe) is presented. Iron boride nanoparticles (FeB-NPs) synthesized by chemical reduction, as well as HNaZ and HNaZ-Fe materials were characterized by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray (EDX), Mossbauer and UV–vis spectroscopies. SEM and TEM measurements showed characteristic spherical shapes associated with FeB-NPs with mean diameter of 120 nm and located on the zeolite’s surface. Whereas the homo-ionized zeolitic material, HNaZ, did not present any type of interactions with MO, the HNaZ-Fe material, with a mass ratio 1:0.06 of HNaZ:Fe, respectively, mostly degraded this dye. The kinetic study showed that the degradation process of MO followed the second order kinetic reaction with a degradation rate constant of 0.0012 g/(mg h) and an 80% dye degradation was always obtained for all used concentrations of MO, which ranged from 50 up to 500 mg/L. The degradation of MO was confirmed by the presence of sulfanilic acid, as detected by UV–vis spectroscopy through the band at 248 nm.

The degradation of methyl orange (MO) dye, in the presence of pure iron nanoparticles (Fe-NPs) and supporting them in natural zeolite-type clinoptilolite (Fe-Z), were studied. The degradation tests consisted of analyzing the dependence of pH, initial concentration of MO, contact time between systems Fe-NPs ↔ MO and Fe-Z ↔ MO, and temperature, respectively. The highest degradation percentages of MO ranging from 80 to 100% occurred at pH values between 3 and 10; below 3 and above 10, relatively low degradation percentages were measured. Whereas nearly 100% of MO degradation was obtained with pure Fe-NPs for all studied MO concentrations and from 30 °C to 50 °C, for the composite Fe-Z, the degradation of MO was both MO concentration and temperature dependent with the highest degradation percentages at 50 °C. Besides, while using pure Fe-NPs the degradation of 100% of MO was reached at a contact time of 6 h at temperatures between 20 °C and 50 °C. However, when using the composite Fe-Z, the degradation percentages of MO were from 80% to 90% which was reached in 17 h, for temperatures between 15 °C and 50 °C. The resulting kinetic degradation data of MO from pure and supported Fe-NPs was analyzed by considering several empirical models, from which the temperature dependent rate constants were obtained, with best values of ~0.2 h−1at 15 °C and ~1.86 h−1at 50 °C and establishing endothermic-degradation processes. By using these rate constants and the Arrhenius relation, an activation energy (Ea) for the degradation process was determined, being for the Fe-NPs ↔ MO system slightly higher than for the Fe-Z↔ MO system.

The nanoparticles technology has received considerable attention for its potential applications in groundwater treatment for the removal of various pollutants as Cadmium. In this work, iron boride nanoparticles were synthesized in pure form and in presence of homo-ionized zeolite clinoptilolite, as support material. These materials were used for removing Cd (II) from aqueous solutions containing 10, 50, 100, 150, 200, 250, 300 and 400 mg/L. The characterization of these materials was made by using X-ray Diffraction, Scanning Electron Microscopy and Mossbauer Spectroscopy. Pure iron boride particles show a broad X-ray diffraction peak centered at 45∘ (2𝜃), inferring the presence of nanocrystals of Fe2B as identified from Mossbauer Spectroscopy. The size of these Fe2B particles was within the range of 50 and 120 nm. The maximum sorption capacities for Cd (II) of iron boride particles and supported iron boride particles in homo-ionized zeolitic material were nearly 100 %. For homo-ionized zeolite and homo-ionized zeolite plus sodium borohydride was ≥ 95 %.

Organometallic compounds made of titanium oxide (TiOx) and pyrrole (Py) were synthesized by plasma to combine the photoelectronic activity of TiO and Py in hybrid materials with potential use in photostimulated processes as photoelectronic devices in pollutant degradation or in solar photocollectors. The Ti precursors were based on titanium tetrapropoxide combined with Py in 1:1 mass ratio in a vacuum tubular glass reactor under resistive electrical glow discharges of water vapor plasmas. The TiOx–Py hybrid compounds with x in the 2.75–3.55 interval absorbed electromagnetic radiation in two regions with different intensities. The first and most intense one was from approximately 190 to 350 nm and the other from roughly 350 to 900 nm, which indicates that in the first interval, the TiO fraction dominates the absorption and that the activity of the second region belonged to Py segments. The electrical conductivity was in the (10−6–10−10) S/m interval with activation energy in the (0.015–2.42) eV range, depending on the reaction time and synthesis conditions.