The oxygen-uranium (O-U) system has various oxides, such as UO2, U4O9, U3O8, and UO3. Uranium dioxide is the most important one because it is used as nuclear fuel in nuclear power plants. UO2 can have a wide stoichiometric variation due to excess or deficiency of oxygen in its crystal lattice, which can cause significant modifications of its proprieties. O/U relation determination by gravimetry cannot differentiate a stoichiometric deviation from contents of other uranium oxides in UO2. The presence of other oxides in the manufacturing of UO2 powder or sintered pellets is a critical factor. Fourier Transform Infrared Spectroscopy (FTIR) was used to identify U3O8 in samples of UO2 powder. UO2 can be identified by bands at 340 cm-1 and 470 cm-1, and U3O8 and UO3 by bands at 735 cm-1, 910 cm-1, respectively. The methodology for sample preparation for FTIR spectra acquisition is presented, as well as the calibration for quantitative measurement of U3O8 in UO2. The content of U3O8 in partially calcined samples of UO2 powder was measured by FTIR with good agreement with X-rays diffractometry (XRD)

Polyvinylidene fluoride (PVDF) is a versatile and low-cost polymer with high biocompatibility, mechanical strength, chemical resistance, thermal stability, and ferroelectricity. This material has been widely used in many applications, ranging from membranes to electronic devices. In this study, self-supporting, flexible, and lightweight PVDF films were prepared by an evaporation route using a low-toxicity solvent (dimethyl sulfoxide – DMSO). Graphene oxide (GO) and anatase titania (TiO₂) were incorporated into the PVDF after preparing DMSO-based suspensions of these materials. The prepared materials were examined in terms of their structural, electrical, and wetting properties before and after exposure to near ultraviolet (UV-A) light. Substantial structural changes took place after incorporating GO and TiO₂ into PVDF. Such modifications were accompanied by dramatic changes in the wetting and electrical properties of the PVDF. UV-A light caused the formation of surface defects on PVDF and GO films. In addition, it promoted the photoreduction of GO into reduced graphene oxide (rGO). Composites containing TiO₂ showed high resistance to UV-A light, probably because titania particles absorb the incoming photons and shield the polymer matrix. This study provides new insights into the synthesis and characterization of PVDF/TiO₂/GO composite films, which may be useful for many applications, including flexible electronics, solar cells, and biomedical devices.

Regrettably, glioblastoma multiforme (GBM) remains the deadliest form of brain cancer, with a very unfavorable prognosis for life expectancy for the patient. We report, for the first time, the green colloidal synthesis of cobalt-doped magnetic iron oxide nanoparticles (Co-MNPs) as aqueous ferrofluids, using two anionic polysaccharide biopolymers, hyaluronic acid (HA) and carboxymethyl cellulose (CMC), as surfactants. These ferrofluids based on magnetite nanoparticles (HA@Co-MNP and CMC@Co-MNP) demonstrated superparamagnetic properties and magnetic-to-thermal conversion upon exposure to an alternating magnetic field (AMF), with the extent of conversion dependent on surfactant type. In addition, the ferrophase acted as a nanozyme, mimicking peroxidase-like activity in response to hydrogen peroxide, which is present at higher levels in tumor cells. The coupling of magnetic-heat capabilities with biocatalytic behavior enhances glioblastoma cell elimination and suppresses 3D neurospheroid growth. The results also showed that active targeting based on the HA biopolymer shell, due to its affinity for CD44 membrane receptors overexpressed in GBM, outperformed CMC-coated ferrofluid analogs. These magnetocatalytic-responsive nanoplatforms offer a broad avenue for the diagnosis and therapy of numerous cancers, potentially improving patients’ quality of life and prognoses.