Hydrogen generation via the hydrolysis of sodium tetrahydridoborate (NaBH₄) is attractive for in situ-demand applications that require hydrogen gas as an energy source or as a reducing agent. Herein, sulfuric acid-assisted carbonization of Zr-based metal–organic frameworks (MOFs) produced a solid acid zirconium oxo sulfate/carbon (ZrOSO₄/C). X-ray diffraction, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy/mapping, nitrogen gas adsorption–desorption isotherm, and X-ray photoelectron spectroscopy were used to characterize the material’s phase purity and porosity. Data analysis confirmed the porosity and crystallinity of ZrOSO₄/C. The materials catalyzed the hydrolysis process of NaBH₄, producing a high hydrogen generation rate. The acidity of ZrOSO₄/C plays a vital role in the material’s catalytic performance. These observations may open a gateway for new exploration toward designing an effective catalyst for the release of hydrogen gas using hydrides.

In this study, we present a facile, one-step method for the manufacturing of all-cellulose, layered membranes containing cellulose nanocrystals (CNC), TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidized cellulose nanofibers (TO-CNF), or zwitterionic polymer grafted cellulose nanocrystals (CNC-g-PCysMA) as functional entities in combination with cellulose fibers and commercial grade microfibrillated cellulose. The presence of active sites such as hydroxyl, carbonyl, thioethers, and amines, gave the membranes high adsorption capacities for the metal ions Au (III), Co (II), and Fe (III), as well as the cationic organic dye methylene blue (MB). Furthermore, the membranes served as excellent metal-free catalysts for the decolorization of dyes via hydrogenation. A 3-fold increase of the hydrogenation efficiency for cationic dyes such as rhodamine B (RhB) and methylene blue was obtained in the presence of membranes compared to NaBH₄ alone. Water-based processing, the abundance of the component materials, and the multifunctional characteristics of the membranes ensure their potential as excellent candidates for water purification systems.

The comparison between crustal stress and surface strain azimuthal patterns has provided new insights into several complex tectonic settings worldwide. Here, we performed such a comparison for Egypt taking into account updated datasets of seismological and geodetic observations. In north-eastern Egypt, the stress field shows a fan-shaped azimuthal pattern with a WNW–ESE orientation on the Cairo region, which progressively rotated to NW–SE along the Gulf of Aqaba. The stress field shows a prevailing normal faulting regime, however, along the Sinai/Arabia plate boundary it coexists with a strike–slip faulting one (σ₁ ≅ σ₂ > σ₃), while on the Gulf of Suez, it is characterized by crustal extension occurring on near-orthogonal directions (σ₁ > σ₂ ≅ σ₃). On the Nile Delta, the maximum horizontal stress (S_Hmax) pattern shows scattered orientations, while on the Aswan region, it has a WNW–ESE strike with pure strike–slip features. The strain-rate field shows the largest values along the Red Sea and the Sinai/Arabia plate boundary. Crustal stretching (up to 40 nanostrain/yr) occurs on these areas with WSW–ENE and NE–SW orientations, while crustal contraction occurs on northern Nile Delta (10 nanostrain/yr) and offshore (~35 nanostrain/yr) with E–W and N–S orientations, respectively. The comparison between stress and strain orientations over the investigated area reveals that both patterns are near-parallel and driven by the same large-scale tectonic processes.

Querétaro city is situated in the north central part of the Trans-Mexican Volcanic Belt, and it was considered by several previous studies as an aseismic region. Since that, as well as considering the surrounding seismotectonic setting, it was significant to assess the seismic hazard across the city which aids in the development and updating the building codes and the seismic design criteria. In this regard, the Horizontal to Vertical Spectral Ratio (HVSR) Nakamura's technique has been applied to investigate the local-site effects across the city. Microtremor measurements were performed at 76 free-field selected sites, through the implementation of portable seismic stations equipped with three-component velocity sensors of Trillium Compact 120 s broadband seismometer. Then, acceleration values were estimated by generating synthetic accelerograms based on a recently-developed algorithm that combines the HVSR technique and the theory of random vibrations, considering as a reference the September 19, 2017 (Mw 7.1) intraslab earthquake recorded at the Centro de Geociencias (CGEO) Seismic Station, in Juriquilla, Querétaro. Finally, by computing the pseudoacceleration response spectra through the linear acceleration method at structural periods of 0.1, 0.5, 1.0, 2.0, and 5.0 s, corresponding seismic hazard maps were established for the studied region. Based on these values and delimiting the areas with higher risk considering the interaction of the soil with the buildings on it, this article is the basis for delimiting seismic parameters that define the city, with future applications in the seismic engineering considering both linear and nonlinear structural behaviors.