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Detailed stratigraphic studies of the Paleocene-lower Eocene interval were conducted on four stratigraphic successions (Sudr-Alhitan, Thamad, Abu-Qada, and Nukhul) in central and southwestern Sinai. These sections are arranged along a North-South direction as: Sudr-Alhitan, Thamad, Abu-Qada, and Nukhul. The biostratigraphic framework was achieved by integrating data of calcareous nannofossils and planktonic foraminifera. The studied area experienced two major tectonic events, most likely related to the Syrian Arc System (SAS), which led to two distinct hiatuses of significant magnitude, evidenced from integrated biostratigraphic analysis and thorough field observations. Benthic foraminifera assemblages suggest a deposition in outer neritic to upper bathyal setting for investigated sites, except for the Tarawan and Thebes formations in Abu-Qada and Sudr-Alhitan sections, which were deposited in middle-outer neritic and outer neritic settings, respectively. Benthic foraminiferal indices indicate an oligo-mesotrophic environment associated with oxic/suboxic conditions at the bottom of the seawater for the studied interval. Low oxygen levels and mesotrophic conditions were seen to mark the Paleocene Eocene Thermal Maximum event, as evidenced by the organic-rich laminated sediment, low benthic foraminiferal indices, and the occurrence of agglutinated taxa Repmanina charoides and Ammobaculites spp., which reflects a major change in food supply. The obtained sequence stratigraphic framework shows that the depositional record of the studied area is significantly influenced by both the regional tectonics and eustatic sea level.
Image processing of multispectral data (Landsat-8 and ASTER) in combination with field studies and petrographic investigations was used for the lithologic mapping of the highly fractionated Humr Akarim (HA) granite pluton and the adjacent area in the Eastern Desert of Egypt. The image processing techniques applied include data transformation techniques such as band ratio, principal component analysis, and minimum noise fraction. Processing of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data is suitable for distinguishing the lithologic units of the HA granite pluton, which have similar mineralogy and chemical composition but differ in texture and microstructures. False Color Composite (FCC) image of the principal component based on standard deviation (PC4, PC2, and PC7 in RGB) is the most appropriate processing technique and effectively highlights significant geological features in HA granite pluton. In comparison to the HA granite pluton, analysis of Landsat images is more favorable and accurate in distinguishing the lithologic units, layering, and folding in the surrounding metavolcanoclastic rocks. Verification of the resulting geological map in the field shows high accuracy and reliability. The resulting geological map is more elaborated and detailed compared to previously published maps based only on field observations, petrographic studies, and chemical composition. It is suggests that the high-intensity lineaments zones detected on the Landsat 8 panchromatic band are zones of significant amounts of mineralization.
For the Wadi El Mayet, the metagabbro-granodiorite-tonalite intrusive complex (MIC) occupies the eastern sector of famous wadi Mubarak–Dabr complex which considered as the largest intrusion in the Egyptian Eastern Desert. The basement associations in the area include volcano-sedimentary rocks, metavolcanics, and ultramafics. The whole successions were intruded by MIC, and granites. The (MIC) comprises multifarious gabbroic varieties namely: olivine, pyroxene, hornblende, uralitized gabbros and rare amphibolites, while silicic portion includes tonalite and granodiorite. Microprobe analytical chemistry of gabbros and granites refers that: the amphiboles are calcic magnesio hornblende formed at low pressure conditions. Chlorites have corundophillite composition. Plagioclase range between labradorite, andesine and oligoclase. Biotite is mainly siderophylite. Muscovite minerals are mainly cheladonite. Geothermo-barometers calculations reveal crystallization temperatures of 550 °C and 860 °C for granites and metagabbros respectively. The (MIC) cover a wide silica range (44.5–74.5 wt %). It has transitional tholeiitic to calc-alkaline magmas. The gabbroic rocks show distinct fecundity with LILE (e.g. Rb, Ba, U and Th), but show observed shortage in most HFSE (e.g. Zr, Nb, Ta). The REE patterns show enrichment in light REE and posse variably positive Eu. It is suggested that, the gabbroic units were likely generated by fractional crystallization of mafic magmas produced through partial melting of metasomatized mantle within island-arc environments. Tonalite - granodiorite (TG) suite show calc-alkaline magmas of I-type settings. They also exhibit enrichment in Ba, Zr, Hf, Rb, U and Th, while P, Nb, Ta and Sr are depleted. Such reductions are harmonious with fractionation of K-feldspar phases. The (TG) show enrichment of (LREE) compare to (HREE) this proposes either the existence of persistent garnet or LREE fertile magma sources. The (TG) is believed to be formed through dehydration melting processes at lower crust settings. Based on the field, geochemistry and structure elements, the investigated mafic and silicic suites are not linked to a single magma origin. The (MIC) can be comparable with intrusions formed in ensialic island-arcs settings. At subduction zone integration between mantle (basaltic suites) and silicic magmas from lower crust forming the early stages of (MIC) crystallization. The whole association was suffered by insignificant fractionation processes and addition of crustal materials during the final stages of (MIC) emplacement.
Molybdenum disulfide (MoS2), with its low energy bandgap, plays an essential role in removing organic pollutants from wastewater via the mechanism of photocatalysis. In this paper, the 2H phase of MoS2 nanoflowers (NFs) as a photocatalyst was synthesized by the facial one-step hydrothermal method. Various characterization techniques, such as X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDX), and UV-visible spectroscopy, were carried out to investigate the structural, morphological, chemical compositional, and optical properties of MoS2 NFs. The obtained MoS2 NFs have excellent crystallinity with an average grain size of 6.84 nm. The calculated optical bandgap (Eg) of the MoS2 NFs was determined to be 1.82 eV. The photocatalytic activity of the as-prepared MoS2 NFs has been demonstrated by degrading both rhodamine B (RhB) and
methylene blue (MB) dyes under ultraviolet (UV) and visible-light irradiation. The results reflected that in the case of using the UV source, the photocatalytic degradation speed of the MB dye is very close to that of the RhB dye, while the degradation of the RhB dye is still faster and more efficient, especially in the first 20 minutes of the irradiation period. However, in the case of using visible light, the MB dye degraded faster and more efficiently than the RhB dye. In addition, the photocatalytic mechanism has been explained, and MoS2 NFs have shown excellent reusability.
Mo1-xCoxS2 (0 ≤ x ≤ 0.1) nanoparticles were successfully synthesized by using a hydrothermal route. The crystal structure of the prepared samples was investigated by Xray diffraction (XRD), emphasizing that all the prepared samples had a hexagonal structure of MoS2, and revealed an increment in the average particle size from 5 to 8 nm with increasing the cobalt ratio. The morphology was examined using scanning electron microscopy (SEM), and the recorded images of pure and cobalt-doped MoS2 show flowerlike architecture clusters. FT-IR spectroscopy was carried out to detect functional groups and stretching and bending vibrations of chemical bonds existing in all the prepared samples, confirming the presence of Mo-O and Co-O-Co characteristic peaks. The chemical composition of the synthesized samples was determined by energy dispersive Xray (EDX) analysis. The results confirmed the presence of Mo, S, and Co, which are consistent with the proposed formation of Mo1-xCoxS2 nanosystems. Optical properties were examined by UV–Visible spectrophotometry, reflecting allowed direct transitions with an energy band gap that decreases from 1.9 eV to 1.53 eV with increasing cobalt concentration. The photocatalytic degradation efficiency of methylene blue (MB) using pure and different ratios of cobalt-doped MoS2 as catalysts was tested under visible light radiation, and it was noticed that the MB degradation increased with increasing cobalt concentration.
Anaerobic digestion (AD) is considered as a widely applied technology for treatment of organic wastes and ammonia inhibition is a critical challenge for AD. Addition of biochar is known as a promising strategy for mitigating ammonia inhibition. The iron-modified biochar (Fe-ABC) possesses superior pore structure and iron could act as electron carriers, activating microbial activity, which could further alleviate the inhibition. However, mechanisms of blue algae biochar (ABC) and iron-modified biochar (Fe-ABC) affect the releasing of N-acyl homoserine lactone (AHLs) and thus lead to the mitigation of ammonia inhibition are unclear. Therefore, the current study explored how ABC and Fe-ABC improve AD performance under high ammonia levels. The results demonstrated that Fe-ABC could improve the secretion of quorum sensing signal molecules (mainly AHLs) under ammonia inhibition. The increase of AHLs was due to the relieving of ammonia stress and enriched functional anaerobic microorganisms by Fe-ABC. Moreover, increased AHLs by adding Fe-ABC could strengthen extracellular polymeric substances secretion. In addition, microbial community changes were also in agreement with the improved methane production under ammonia stress by increased AHLs. Furthermore, critical enzymes responsible for all stages of AD process were reinforced after introducing Fe-ABC. The current study could provide primary insights for mitigating ammonia inhibition by increased AHLs after adding Fe-ABC.
Plant diseases significantly threaten global food security, with viral infections, particularly Watermelon Mosaic Virus (WMV), causing substantial losses in economically important crops such as squash. This study aims to investigate the efficacy of beneficial bacteria isolated from various plants in promoting growth and mitigating the effects of WMV in squash. Understanding the interactions between plants and beneficial microbes could provide sustainable solutions for managing viral infections in agriculture. Sixty-two bacterial isolates were obtained from the rhizosphere of basil, mint, thyme, and squash plants. Among these, six strains exhibited notable plant growth-promoting activities, including the synthesis of indole acetic acid, solubilization of phosphate and zinc, ammonia production, and activity of 1-aminocyclopropane-1-carboxylate deaminase (ACCD). Morphological observations and 16S rRNA gene sequencing identified these isolates as Pseudomonas indica, Bacillus paramycoides, Bacillus thuringiensis, Bacillus mycoides, Paenibacillus glucanolyticus, and Niallia circulans. In pot experiments, squash plants inoculated with these bacterial strains demonstrated significant reductions in disease severity after being infected with WMV. Specifically, foliar applications of the bacteria resulted in the following reductions in disease severity: B. mycoides (87%), B. thuringiensis (73%), Paenibacillus glucanolyticus (73%), Niallia circulans (70%), B. paramycoides (65%), and Pseudomonas indica (65%). Additionally, plants treated with B. mycoides showed increased plant height and shoot dry weight, indicating enhanced growth performance relative to infected controls. Statistical analysis revealed that these growth promotions and disease severity reduction were significant (p<0.05). GC–MS analysis of the six bacterial strains revealed a diverse array of 73 chemical metabolites, including common compounds such as 9-Octadecenoic acid (Z), benzene derivatives, and cyclopentanones. These findings suggest shared metabolic pathways among the strains and indicate potential roles in ecological interactions, plant defense mechanisms, and antiviral properties. These metabolites likely contribute to the observed reductions in viral severity and enhance plant resilience. The study indicates that inoculating squash plants with specific beneficial bacteria, especially B. mycoides, through foliar or soil application can significantly decrease the severity of WMV and promote plant growth. This approach offers an environmentally friendly alternative to chemical antiviral treatments and may reduce reliance on pesticides. This research highlights the potential of using plant growth-promoting bacteria (PGPB)as a sustainable approach to control viral infections in crops. Further field trials are necessary to PGPB validate the scalability of these findings and assess their effectiveness under diverse agricultural conditions. Incorporating these beneficial microbes into agricultural practices could enhance the resilience of cropping systems, ultimately fostering sustainable agriculture and enhancing food security.
The rapid development of the Internet of Things (IoT) has accelerated the advancement of indoor photovoltaics (IPVs) that directly power wireless IoT devices. The interest in lead-free perovskites for IPVs stems from their similar optoelectronic properties to high-performance lead halide perovskites, but without concerns about toxic lead leakage in indoor environments. However, currently prevalent lead-free perovskite IPVs, especially tin halide perovskites (THPs), still exhibit inferior performance, arising from their uncontrollable crystallization. Here, a novel adhesive bonding strategy is proposed for precisely regulating heterogeneous nucleation kinetics of THPs by introducing alkali metal fluorides. These ionic adhesives boost the work of adhesion at the buried interface between substrates and perovskite film, subsequently reducing the contact angle and energy barrier for heterogeneous nucleation, resulting in high-quality THP films. The resulting THP solar cells achieve an efficiency of 20.12% under indoor illumination at 1000 lux, exceeding all types of lead-free perovskite IPVs and successfully powering radio frequency identification-based sensors.
Tin halide perovskites (THPs) have demonstrated exceptional potential for various applications owing to their
low toxicity and excellent optoelectronic properties. However, the crystallization kinetics of THPs are less controllable than its lead counterpart because of the higher Lewis acidity of Sn2+, leading to THP films with poor morphology and rampant defects. Here, a colloidal zeta potential modulation approach is developed to improve the crystallization kinetics of THP films inspired by the classical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. After adding 3- aminopyrrolidine dihydro iodate (APDI2) in the precursor solution to change the zeta potential of the pristine colloids, the total interaction potential energy between colloidal particles with APDI2 could be controllably reduced, resulting in a higher coagulation probability and a lower critical nuclei concentration. In situ laser light scattering measurements confirmed the increased nucleation rate of the THP colloids with APDI2. The resulting film with APDI2 shows a pinholefree morphology with fewer defects, achieving an impressive efficiency of 15.13%