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The design and synthesis of organic adsorbents for rare earth element (REEs) separation remain significant scientific aspect and industrial endeavor. In a single-pot reaction, acetone and resorcinol in acidic media over a two-day period facilitated the formation of the 2, 4, 4-trimethyl-7, 2′, 4′ trihydroxy flavan (flavan adsorbent). Under acidic conditions, flavan effectively adsorbs REEs (adsorbate), while under alkaline conditions, flavan rapidly dissolves completely. A series of adsorption experiments was conducted to determine the optimal adsorption conditions, including pH variations (1–5), REEs solution concentrations (250–1000 mg/L), adsorption time (5–60 min), and flavan mass (10–100 mg). The maximum adsorption capacity for flavan under optimal conditions was 258 mg g−1. Various analytical instruments were employed for flavan characterization, including Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS), which were essential for analyzing the surface morphology and structural properties of the flavan. Adsorption isotherms suggested that the adsorption of REEs onto the flavan surface followed the Langmuir model, which in turn exhibited a theoretical adsorption capacity of 263.2 mg g−1 better off the Freundlich model. Kinetically, the adsorption of REEs on the flavan is best run in a pseudo-second-order model trajectory, which in turn exhibited an adsorption capacity value of 283 mg g−1. Interference studies revealed that flavan is a selective adsorbent; however, aluminum ions may exert a minor interference effect of 4% (in term of REEs uptake). Other competing elements, including Na, K, Mg, Ba, Mn, Cu, Fe, and Sn, exhibited a minimal decline in flavan uptake for REEs.HighlightsAt present rare earth elements (REEs) are in massive demand globally which in turn is crucial for advanced industries.Synthetic flavan (an affordable adsorbent) is setting ambitious findings for REEs separation in a selective implementation.More importantly flavan is an alkaline-soluble adsorbent that is potentially conducive for promoting REEs separation without desorption studies

Phosphogypsum (PG), the waste byproduct resulting from wet process phosphoric acid production, is employed as a selective and effective adsorbent for total rare earth elements (REEs) from aqueous solution and leach liquor. The elaboration of PG adsorbent complemented after some physical treatments. Adsorption and elution studies carried out in experimental batches, including the effect of pH, adsorbent dose, initial REE concentration, and equilibrium time. Adsorption of REEs onto PG fitted well with Langmuir isotherm with a theoretical capacity surpassed 357 mg/g. REEs were effectively eluted from loaded PG with 2 mol L−1 HCl acid with an efficiency of 94%. PG showed an outstanding selectivity towards REEs in the presence of many cations and anions, for instance (Fe3+, UO22+, Ca2+, SO42−, NO3−). Different qualitative techniques such as EDS, SEM, and FTIR used to emphasize the adsorption of REEs onto PG. The film diffusion model was the preponderant adsorption mechanism for REEs; also, the adsorption process has a good accordance with pseudo-second-order kinetic model.

A composite of rice husk (RH), caustic soda and aluminium oxide was synthesized at 500°C. The activated carbon and amorphous silica dispersed over the aluminium oxide selectively adsorbed uranium in the presence of other elements. At equilibrium time 1 h, phase ratio S/L (0.1 g/10 ml), pH = 5 and uranium initial concentration 120.6 mg/l uranium adsorption efficiency was 96.35%. The uranium stripping efficiency from the load RHA–alumina composite fulfilled 99.9% at 1 h equilibrium time, a phase ratio (S/A) of 0.05 g/10 ml and 0.5 mol/l HNO3. The scanning electron microscopy photos revealed that the rice husk ash (RHA)–alumina composite has vacant or regular cavities before the adsorption, and the cavities are fully occupied by uranium after adsorption. The Fourier transform infrared spectroscopy shows a more broadening of the band υ = 3526 and 3462 cm−1 which was ascribed to the uranium adsorption. The composite adsorbed 93.75% of uranium from a waste sample. The uranium adsorption exhibited a Langmuir isotherm.

This study demonstrates that borosilicate doped with trace amounts of titanium and zirconium (BSZT) serves as an innovative alternative (mock-up laboratory borosilicate glassware) and marks a significant advancement in chromium removal technology. While the manufacturing of borosilicate glass-ceramic (active for Cr(VI) adsorption) typically requires temperatures of 1500 °C, BSZT can be processed effectively at a lower temperature of 900 °C. This reduction in processing temperature is made possible by using sodium metasilicate as a flux and enhancing the silicate content. The composition consists of silica maintained below 84%, borate at approximately 8%, with titanium and zirconium collectively representing 8% weight by weight. To assess the adsorption and desorption properties of this material, various experiments were conducted, altering parameters such as solution pH, contact time, borosilicate weight, and chromium concentration. Advanced characterization techniques—including FTIR, SEM, EDS, and BET—were utilized to evaluate the modified borosilicate’s morphology, bonding, and surface characteristics. Impressively, the modified borosilicate achieved a chromium adsorption efficiency of 65% with an uptake capacity of 25 mg/g in just 30 s. Adsorption isotherm studies indicated that chromium ions adhere more closely to the Langmuir model than to the Freundlich model. Kinetic analyses further confirmed that the adsorption process is chemically driven and aligns with the pseudo-second-order model.HighlightsCurrently, there is a significant demand for chromium (Cr) removal due to its crucial implications for health and environmental concerns.The synthetic borosilicate glass-ceramic reinforced with zirconium and titanium, named as BSZT, has shown promising results for the rapid removal of chromium in its hexavalent form (Cr VI).Importantly, extensive studies have been conducted on BSZT as a sorbent for Cr VI removal, utilizing various advanced analytical techniques for thorough characterization.

In this study, Acrylic acid (AA), acrylamide (AM), and 16,16-dimethylheptadecan-1-amine (PJM-T) were copolymerized using gamma irradiation with 60Co γ-rays at a dose of 25 KGy to form a novel composite; Poly(acrylic acid-co-acrylamide/16,16-dimethylheptadecan-1-amine P(AA-co-AM/PJM-T). P(AA-co-AM/PJM-T) is characterized by different physicochemical techniques and used as a sorbent for rare earth elements from monazite. The optimum pH for the sorption process at 25 ℃ is 4.5 and the equilibrium attained at 60 min. Different kinetics and isothermal models is applied. The maximum adsorption capacity is 182.15 ± 3.73 mg g−1 at 25 ℃. The sorption reaction regulates a pseudo 2nd order mechanism and the process is spontaneous.

In this study, a synthetic BaSO 4 ·CaSO 4 composite was prepared by co-precipitation technique, characterised and examined for REE sorption. The sorption parameters were; pH = 4, equilibrium time = 20 min, temperature = 303 K, and REE liquor volume to composite mass ratio of 0.2:1 L g −1 . The sorption reaction was controlled by pseudo 2nd order kinetic mechanism and Langmuir adsorption isotherm with an adsorption capacity of 168.63 mg g −1 . 90.14% of REE (III) was desorbed using 1 mol L −1 HNO 3. The process was endothermic and spontaneous. Accordingly, 1:1 barite-gypsum (natural ingredient for BaSO 4 ·CaSO 4 ), with 136 mg g −1 loading capacity, was used for REEs extraction.

The synthesis, characterization, and testing of new inorganic compounds as perspective adsorbents or ion exchangers are of significant importance. Magnesium fluoride is a well-known inorganic compound that is affordable and widely used in various scientific and industrial applications. A series of adsorption experiments have been conducted, including investigations of pH range, magnesium fluoride dose weights, initial concentration of the Rare earth elements (REEs) and adsorption time. An outstanding finding regarding magnesium fluoride as an adsorbent is that REEs were separated at pH 1 through ion exchange and at pH 4 through adsorption mechanisms, showing nearly identical uptake of 191 mg/g. Under optimal adsorption conditions, the REEs were adsorbed on magnesium fluoride with an uptake of 302.4 mg. The morphological traits of magnesium fluoride were characterized using energy dispersive spectroscopy (EDS), scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR). Kinetically, the adsorption of REEs on magnesium fluoride aligns with the pseudo-second-order model and exhibits a theoretical loading capacity of 310 mg/g. What’s more, isothermally, the adsorption of REEs corresponds to the Langmuir model and predicts a theoretical uptake of 305 mg/g. Interference studies indicate that magnesium fluoride is a promising adsorbent and exhibits notable selectivity. The study suggested that magnesium fluoride has shown a higher saturation capacity compared to other Group IIA fluorides. From a sustainability perspective, magnesium fluoride has been sourced from the Mediterranean Sea. This approach achieved a REEs separation capacity of 308.7 mg/g after implementing all the optimum sol-gel magnesium fluoride adsorption conditions. Graphical Abstract Highlights Synthesis of an affordable, selective and sustainable sorbent magnesium fluoride (MgF 2 ) for rare earth elements (REEs) capture. The magnesium fluoride separates REEs in the pH range of 1–4 at the same REEs saturation capacity and efficacy, practically, the separation of REEs at pH 1 occurred entirely by ion exchange mechanism, and by adsorption mechanism at pH 4. Magnesium fluoride demonstrates optimal selectivity at pH 1 and exhibits moderate selectivity at pH 4. Magnesium fluoride outperformed other Group 2 fluorides in REEs separation in the following order: MgF 2  > CaF 2  > BaF 2  > SrF 2 . The Mediterranean Sea was utilized as a sustainable magnesium source and effectively separated REEs.

Integration of potential field- and structural data make it possible to trace surface and subsurface large-scale geological structures of the Egyptian Nubian Shield (ENS). Obtained results indicate that the Northern Eastern Desert (NED) of the ENS is dominated by relatively younger (c. 580 Ma) E–W and NE–SW trending extensional structures that were controlled by the evolution and retreat of the Cadomian Arc. Density of such extensional structures increases with depth as displayed by the potential data. The prevailing structural trends in the Central Eastern Desert (CED) are NW–SE and WNW–ESE. Both trends are highly prompted by the timing of deformation upon the Najd Fault System, and are themselves dissected by a relatively younger NE–SW shearing trend. Lineament density in the CED is subordinate for both subsurface and near surface structures. The South Eastern Desert exhibits compressional and extrusion-related structures of two main prominent trends; WNW-to-NW (to the western part) and the N-, NNE- to NE (to the eastern part). The previously mentioned Neoproterozoic trends are remarkably influenced by the Oligocene–Miocene Red Sea-Gulf of Suez rift related fractures in the vicinity of the rift shoulder. The remarkable change in trends and densities of structural trends, especially in the NED, is interpreted in terms of concealing of the older structures by the younger extensional structures which in turns reflect an N-ward progressive deformation in the entire ENS. Gravity data are more appropriate in delineating the structural trends compared to the magnetic data which are largely affected by lithological variations and/or alteration zones and magnetic mineralogy.

This is a comprehensive review of the principles and applications of adaptive optics (AO) in ophthalmology. It has been combined with flood illumination ophthalmoscopy, scanning laser ophthalmoscopy, as well as optical coherence tomography to image photoreceptors, retinal pigment epithelium (RPE), retinal ganglion cells, lamina cribrosa and the retinal vasculature. In this review, we highlight the clinical studies that have utilised AO to understand disease mechanisms. However, there are some limitations to using AO in a clinical setting including the cost of running an AO imaging service, the time needed to scan patients, the lack of normative databases and the very small size of area imaged. However, it is undoubtedly an exceptional research tool that enables visualisation of the retina at a cellular level.

Overactive bladder (OAB) is a common chronic condition that can have a significant impact on quality of life (HRQL). We aimed to assess the prevalence of OAB bother and its related quality of life among medical students in Egypt. A cross-sectional study among medical students in Egypt. An online questionnaire was shared via online platforms to collect the intended participants. We used the Overactive Bladder Symptoms and Health-Related Quality of Life Short Form (OAB-q SF). We assessed the difference between participants in their baseline characteristics using the Mann–Whitney U and Kruskal–Wallis Tests. We performed a multiple linear regression to assess the potential risk factors. 1003 participants completed the questionnaire. The median transformed OAB bother score was 10[3.33, 23.33], while the median transformed score of HRQL was 93.8[80, 98.46]. The prevalence was about 15%, while about 51.65% reported a decline in HRQL. A statistically significant association between OAB bother and academic phase, energy drink, or satisfaction with social life was reported. We found no association between OAB bother and caffeinated drinks or smoking. Finally, neither age, gender, nor BMI had an association with OAB bother. A low prevalence of OAB among medical students was found. Consumption of Energy drinks was found to be a risk factor, while caffeinated drinks had no effect. OAB was found to be higher in the academic phase than in the clinical one. Several studies should be conducted to further assess the risk factors of overactive bladder. Clinicaltrials.gov registration: NCT07044778, June 2025.