Gabal El-Ineigi fluorite-bearing rare-metal granite with A-type affinity, located in the Central Eastern Desert of Egypt, is distinguished by its abundance of large fluorite-quartz veins and mafic enclaves. Plagioclase (labradorite to oligoclase), Mg-rich biotite, and Mg-rich hornblende are the main components of mafic enclaves, with significant amounts of fluorite as essential phases, and titanite and Fe-Ti oxides (Nb-free rutile and ilmenite-rutile solid solution) as the main accessories. These enclaves are monzodioritic in composition, Si-poor, and highly enriched in Ca, Fe, Mg, and F compared to the host alkali feldspar F-poor Si-rich granites. Given the conflicting evidence for a restitic, xenolithic, magma mixing/mingling, cumulate, or bimodal origin for these enclaves, we propose that the mafic enclaves and felsic host granites are two conjugate liquids, with contrasting compositions, of a single parental melt. This is inferred by the normalized REE patterns that are similar. As a result, liquid immiscibility is proposed as a probable explanation for this mafic–felsic rock association. These enclaves can be interpreted as transient melt phases between pure silicate and calcium-fluoride melts that are preserved from the early stages of separation before evolving into a pure fluoride (Ca-F) melt during magma evolution. Due to element partitioning related to melt unmixing, the enclaves are preferentially enriched in Ca, F, Li, Y, and REE and depleted in HFSE (such as Zr, U, Th, Ta, Nb, Hf, and Ga) in comparison to the host granites. Furthermore, mafic enclaves exhibit W-type tetrad effects, while host granites exhibit M-type tetrad effects, implying that the REE

Introduction: Bacterial infections caused by different strains of bacteria still one of the most important disorders affecting humans worldwide. Polymers nanocomposite systems could be considered as an alternative to conventional antibiotics to eradicate bacterial infections. Significance: In an attempt to enhance the antibacterial performance of silver and iron oxide nanoparticles, decrease their aggregation and toxicity, a polymeric hybrid nanocomposite system combining both nanoparticles is produced. Methods: Magnetic Ag–Fe3O4@polymer hybrid nanocomposites prepared using different polymers, namely polyethylene glycol 4000, ethyl cellulose, and chitosan were synthesized via wet impregnation and ball-milling techniques. The produced nanocomposites were tested for their physical properties and antibacterial activities. Results: XRD, FT-IR, VSM, and TEM results confirmed the successful preparation of hybrid nanocomposites. Hybrid nanocomposites have average crystallite sizes in the following order Ag–Fe3O4@CS (8.9 nm) < Ag– Fe3O4@EC (9.0 nm) < Ag–Fe3O4@PEG4000 (9.4 nm) and active surface area of this trend Ag–Fe3O4@CS (130.4 m2 g−1 ) > Ag–Fe3O4@EC (128.9 m2 g−1 ) > Ag–Fe3O4@PEG4000 (123.4 m2 g−1 ). In addition, they have a saturation magnetization in this order: Ag–Fe3O4@PEG4000 (44.82 emu/g) > Ag–Fe3O4@EC (40.14 emu/ g) > Ag–Fe3O4@CS (22.90 emu/g). Hybrid nanocomposites have a pronounced antibacterial action against Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus intermedius compared to iron oxide nanoparticles and positive antibacterial drug. In addition, both Ag–Fe3O4@EC and Ag–Fe3O4@CS have a lower MIC values compared to Ag–Fe3O4@PEG and positive control. Conclusion: Magnetic Ag–Fe3O4 hybrid nanocomposites could be promising antibacterial nanomaterials and could pave the way for the development of new materials with even more unique properties and applications.

In this work, pure Co3O4, Ni-, CuNi-, and CdNi-doped Co3O4 nanoparticles (NPs) were prepared via chemical coprecipitation method. The obtained Co3O4 exhibits a cubic crystalline structure with an average crystallite size of ~19.9 nm, according to the XRD profiles. Moreover, the effects of Ni-, CuNi- and CdNi-doped Co3O4 on the crystallite size, band gap, and magnetic properties of the cubic Co3O4 were considered. It was observed that the crystallite sizes and the magnetic properties of Ni(0.1)Co3O4(0.9) and Cu(0.05)Ni(0.05)Co3O4(0.9) samples are smaller, while the optical band gaps are wider than that of pure Co3O4. The Cd(0.05)Ni(0.05)Co3O4(0.9) sample has a higher magnetic properties in comparison to the other samples. The elemental composition of the produced Co3O4, Ni-, CuNi- and CdNi-doped Co3O4 NPs is determined using the EDX technique. A morphological study by TEM showed that the CdNi-doped Co3O4 sample has semi-spherical particles with an average particle diameter of ~70.4 nm. The photodegradation of methyl orange (MO) dye in aqueous solution under visible light irradiation was used to examine the catalytic activity of pure and doped Co3O4 NPs. The results showed that the degradation of MO dye was improved in the doped samples and takes the following order: Cd(0.05)Ni(0.05)Co3O4(0.9) (~93%) > Cu(0.05)Ni(0.05)Co3O4(0.9) (~85%) > Ni(0.1)Co3O4(0.9) (~79.7%) > pure Co3O4 (~64.4%) in 120 min of irradiation time. The pseudo-first-order reaction rate constant for Cd(0.05)Ni(0.05)Co3O4(0.9) is equal to 0.021 min− 1 , which is about 1.6-times increased in compared to pure Co3O4. The improved photocatalytic efficiency of this sample was attributed to an extrinsic defect generated by CdNi doping, small particle sized and high surface area, which delayed the electron/hole recombination and caused appropriate band gap configuration

Metallic nanoparticles embedded in the polymer matrix are considered a significant category of heterogeneous catalysts with strong catalytic performance. Functionalized polymers are inexpensive building blocks that make good catalytic platforms for stabilizing metallic nanoparticles. In this study, Fe3O4@CMC-Cu magnetic nanocomposites were successfully synthesized and characterized by XRD, FTIR, BET, XPS, VSM, HR-TEM, and EDX mapping. Morphology observation shows that spherical Fe3O4 magnetic nanoparticles and Cu NPs are distributed uniformly and encapsulated inside the polymer structure with an average diameter of ~ 11 nm without substantial agglomeration. Additionally, the inclusion of CMC polymer and Cu NPs gradually reduces the magnetic saturation of Fe3O4. The reduction of 4-nitrophenol (4-NP) and the organic dyes Congo red (CR) and acriflavine (ACF) in aqueous medium at room temperature was used to test the nanocomposites’ catalytic activity. The effects of reaction parameters, catalyst amount and Cu NPs percentages on the catalytic effectiveness were determined. The induction time of the reaction decreases with increasing the nanocomposite amount and the Cu NPs loading percentages. Excellent catalytic activity was demonstrated by the Fe3O4@CMC-Cu (10 %) nanocomposite for the elimination of all three intended organic contaminants (4-NP, CR and ACF). For the reduction of 4-NP, CR, and ACF, the calculated Kapp values were 1.55 min− 1 , 0.3 min− 1 , and 2.3 min− 1 , respectively. The magnetic nanocomposite was easily separated from the reaction solution and recycled for up to five successive cycles without suffering a substantial decrease in the catalytic activity. Such magnetic nanocomposites provide light on highly effective catalysts for applications in environmental protection