In this work, nanoparticles of zinc oxide were synthesized; they were formed using the sol-gel method (citrate route) at calcination temperatures (Tc) of 500, 550 and 600 °C. For all samples studied, IR spectroscopy showed the presence of the bands associated with water molecules present in the zinc oxide and carbon dioxide adsorbed on its surface. The formation of zinc oxide phase was confirmed by XRD, which showed that from 500 ºC it had this type of Wurtzite structure. However, samples calcinated at 600 ºC have higher crystallinity. Crystallite size was calculated using the Scherrer equation. The Rietveld method was used to obtain lattice parameters a and c for Wurtzite cell types as well as cell volume and the ratio c/a of each sample. These parameters do not show significant changes when they are compared with values obtained from samples with different calcination temperatures. Electron paramagnetic resonance showed the presence of defects in the zinc oxide. Three signals with g values of 1.96, 2.00 and 2.04 were associated with oxygen and zinc vacancies. Defects in the structure disappear when the calcination temperature is increased. The sample that was highlighted with the highest concentration of vacancies has a mean crystallite size greater than 30 nm, and this may also be responsible for this feature.

Geoscientists commonly focus on Tertiary units to understand the Andean uplift and deformation of the eastern Cordillera of Colombia, whereas the Cretaceous evolution remains poorly known. Cretaceous units are exposed in western Eastern Cordillera, but outcrops are scarce in the Middle Magdalena Valley. Recent seismic acquisition programs and new wells drilled through the Cretaceous succession led to a better understanding of unconformities and sequences in both the Middle Magdalena Valley and the western flank of the Eastern Cordillera. This paper identifies unconformities bounding seismic sequences and deciphers Cretaceous structural deformation in the Middle Magdalena Valley and western Eastern Cordillera based on the interpretation of sizable seismic reflection sections and well information. The analysis of sedimentary sequences and unconformity surfaces allowed identification of stages of pre-Eocene deformation. Regional correlations of sequences and unconformities recognized here with those identified by other authors support the occurrence of Cretaceous regional tectonic events.

Energy levels associated with several crystalline defects, such as zinc (V_Zn) and oxygen (V_O) vacancies, Zn and O interstitials (Zn_i and O_i respectively), Zn and O antisite defects, and charged oxygen vacancies Vo-, among others, are generated by the introduction of cobalt (Co) into the structure. The effective introduction of Co into the Zn occupancy site was evaluated by XRD and electron paramagnetic resonance. The EPR spectra remain consistent across all doping concentrations of Co²⁺ ions and revealed intriguing features linked to four distinct Co²⁺ paramagnetic centers; among them, a pair of Co²⁺ ions exhibited ferromagnetic coupling. ZnO nanocrystals doped with cobalt were produced by sol gel and their use as photocatalysts were evaluated in the degradation of the Congo red pollutant. The degradation efficiency improved by more than 50% when compared to the efficiency of pure ZnO nanocrystals at the same activity time.

Seismic inversion, a nonlinear, non-unique-solution, and human-prone error problem, seeks the optimal solution in multivariate space, a task that AI algorithms perform better. So, inversion with AI becomes appropriate to extract information from post-stack data. A probabilistic neural network (PNN) and deep feedforward neural network (DFNN) inverted seismic data using multiattributes, and their results were compared with those provided by a model-based inversion (MBI). Applied to a post-stack volume of the Frontier Formation at the Teapot-Dome field, Wyoming-USA, the three methods provided porosity volumes (ϕ), gamma rays (GR), and Lamé impedances (µρ, λρ). The comparison between well-logs and the provided volumes revealed a reliable PNN prediction, while DFNN achieved the best geologically correlated parameter sections and a less reliable MBI prediction. The geomorphological time-slice analysis discriminated high ϕ-µρ areas and low GR–λρ areas, geologically interpreted as a deltaic environment, with distributary channels and beachfront lobes subject to the action of the tides, which agrees with the well-log interpretation and the basin geological evolution. The results enhanced the stacked section’s importance by the geological information contained, which would contribute to reducing the prospecting risk. Finally, PNN and DFNN encouraging results reaffirm their best searching-in-multivariate space ability.