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ZnO-ZrO2 nanocomposites using zinc (II) acetylacetonate and different ZnO contents (13, 25, 50, and 75% mol) were synthesized through sol-gel method. The synthesis process was strongly related to nanocomposite properties especially on their structural composition. The obtained ZnO-ZrO2 nanomaterials presented tetragonal crystalline structure for zirconia whereas hexagonal one was formed in ZnO. Raman spectroscopy and XRD patterns confirmed the formation of tetragonal zirconia whereas inhibition of monoclinic structure was observed. Addition of ZnO affected the pore size distribution of the composite, and the measured specific surface areas were from 10 m2/g (for pure ZnO) to 46 m2/g (pristine ZrO2). Eg values of ZrO2 were modified by ZnO addition, since calculated values using Kubelka-Munk's function varied from 4.73 to 3.76 eV. The morphology and size of the nanomaterials investigated by electron microscopy showed formation of nanorods for ZnO with sizes ranging from 50 nm to 300 nm while zirconia was formed by smaller particles (less than 50 nm). The main advantage of using the nanocomposite for photocatalytic degradation of phenol was the mineralization degree, since 75ZnO-ZrO2 nanocomposite surpassed mineralization reached by pure ZnO and also inhibited formation of undesirable intermediates. [ABSTRACT FROM AUTHOR]

The absence of an effective treatment for malignant brain tumors like Glioblastoma multiforme (GBM), has been stimulate researchers in the search of alternatives that allow to offer a solution that improves the quality of life and in addition it could prolong it. Current knowledge on the biological processes allows us a better understanding of the phenomena, as well as the opportunity to design more effective treatments. Nowadays, with nanotechnology tools, the design of highly selective materials represents the opportunity with strongest potential in the mid to long term, to be able to offer early diagnosis techniques and selective treatments that impact in survival and the quality of life, in patients with malignant brain tumors. [ABSTRACT FROM AUTHOR]

The absence of an effective treatment for malignant brain tumors like Glioblastoma multiforme (GBM), has been stimulate researchers in the search of alternatives that allow to offer a solution that improves the quality of life and in addition it could prolong it. Current knowledge on the biological processes allows us a better understanding of the phenomena, as well as the opportunity to design more effective treatments. Nowadays, with nanotechnology tools, the design of highly selective materials represents the opportunity with strongest potential in the mid to long term, to be able to offer early diagnosis techniques and selective treatments that impact in survival and the quality of life, in patients with malignant brain tumors. [ABSTRACT FROM AUTHOR]

The study of the interaction between graphene oxide (GO) and arsenic is of great relevance not only in the design of adsorbent materials to remove this contaminant but also in the understanding of its combined nanotoxicity. In this work, we show that As(III) adsorption, primarily H 3 AsO 3 , by graphene oxide is affected by its degree of oxidation. Three types of GO with C/O ratios between 1.35 and 1.98 were produced, resulting in important variations in the concentration of COH and COC functional groups. The less oxidized material reached a maximum As(III) adsorption capacity of 123 mg/g, whereas the GO with the highest degree of oxidation reached a value of 288 mg/g at pH 7, the highest reported in the literature. We also show that sulfates and carbonates present in water strongly inhibit As(III) adsorption. The interaction between graphene oxide and As(III) was also studied by Density Functional Theory (DFT) computer models showing that graphene oxide interacts with As(III) primarily through hydrogen bonds, having interaction energies with the hydroxyl and epoxide groups of 1508.6 and 1583.6 kJ/mol, respectively. Finally, cytotoxicity tests showed that the graphene oxide maintained cellular viability of 57% with 50 μg/ml, regardless of its degree of oxidation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this work, we describe a methodology for developing a mathematical model based on infrared (IR) detection to determine the moisture content (M) in solid samples. For this purpose, an experimental setup was designed, developed and calibrated against the gravimetric method. The experimental arrangement allowed for the simultaneous measurement of M and the electromotive force (EMF), fitting the experimental variables as much as possible. These variables were correlated by a mathematical model, and the obtained correlation was M=1.12×exp(3.47×EMF), ±2.54%. This finding suggests that it is feasible to measure the moisture content when it has greater values than 2.54%. The proposed methodology could be used for different conditions of temperature, relative humidity and drying rates to evaluate the influence of these variables on the amount of energy received by the IR detector., (Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.)