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Creators/Authors contains: "Hassan, Mohamed"

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  1. The presence of poly‐ and perfluoroalkyl substances (PFAS) in the environment is associated with adverse health effects but measuring PFAS is challenging due to the associated high cost and technical complexities of the analysis. Here, the reactivity of atomically precise metal‐oxo clusters is reported and the foundation for their use is provided as fluorescent nanosensors for PFAS detection. The material comprises crystalline, water soluble, hexanuclear cerium‐oxo clusters [Ce63‐O)43‐OH)4]12+decorated with glycine molecules (Ce‐Gly) characterized by fluorescence emission at 353 nm. The Ce‐Gly fluorescence is found sensitive to long chain carboxylated PFAS of CF3–(CF2)n–, where n ≥ 6, such as perfluorooctanoic, perfluorononanoic and perfluorodecanoic acids. This unique reactivity leads to a change in the emission spectra in a concentration dependent manner, enabling PFAS detection through ligand exchange and aggregation‐induced emission (AIE) enhancement. No significant cross‐reactivity from potentially co‐existing species, including sulfonated PFAS, octanoic and dodecanoic acids, humic acid, and inorganic ions is observed. With an optimal concentration of 3.3 µg mL−1Ce‐Gly, the method demonstrated detection limits of 0.24 ppb for PFOA and 0.4 ppb for PFNA. These findings highlight the potential of fluorescence‐based detection strategies utilizing nanoscale probes such as Ce‐Gly as fluorescent probes and nanosensors for PFAS. 
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  2. Cerium oxide nanoparticles (CeNPs) are versatile materials with unique and unusual properties that vary depending on their surface chemistry, size, shape, coating, oxidation states, crystallinity, dopant, structural and surface defects. This review details advances made over the past twenty years in the development of CeNPs and ceria-based nanostructures, the structural determinants affecting their activity, and translation of these distinct features into applications. The two-oxidation states of nanosized CeNPs (Ce3+/Ce4+) coexisting at the nanoscale level, facilitate formation of oxygen vacancies and defect states which confer extremely high reactivity and oxygen buffering capacity, and the ability to act as catalysts for oxidation and reduction reactions. However, the method of synthesis, surface functionalization, surface coating and defects are important factors in determining their properties. This review highlights the key properties of CeNPs, their synthesis, interactions and reaction pathways, and provides examples of emerging applications. Due to their unique properties, CeNPs have become quintessential candidates for catalysis, chemical mechanical planarization (CMP), sensing, biomedical applications and environmental remediation, with tremendous potential to create novel products and translational innovations in a wide range of industries. This review highlights the timely relevance and the transformative potential of these materials in addressing societal challenges and driving technological advancements across these fields. 
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  3. An environmentally responsible synthesis of Na2/3[Ni1/3Mn2/3]O2(NNMO) enabled by direct conversion of metallic Ni powder, releasing only O2and H2O as byproducts. The resulting NNMO exhibits excellent cycling performance as a Na-ion battery cathode. 
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  4. In Fall of 2024, central Florida was impacted by Hurricane Helene (landfall in Perry, FL as a Cat 4 hurricane on Sept 27) and by Hurricane Milton (landfall in Siesta Key, FL as Cat 3 on Oct 9). The hurricanes led to damages of an estimated value > $200billion. The Nearshore Extreme Events Reconnaissance Association (NEER) and the Geotechnical Extreme Events Reconnaissance Association (GEER) represented by their members from more than 10 academic institutions, federal agencies, and industry and supported by technical staff from the NHERI RAPID facility and the UF Center for Coastal Solutions initiated on Sept 23 a data collection effort that included pre-, during-, and post-storm multi-disciplinary data collections efforts. The field data collection effort was concluded on Nov 22. Data includes hydraulic information on storm surge, waves, and currents, topographic and bathymetric data sets, terrestrial and seabed mapping, and geotechnical site characterization including in-situ testing, sediment sampling, and seismic testing. Data was collected in four focus areas in Florida (Cedar Key; Horseshoe Beach; Midnight Pass and Milton Pass, both near Venice) and observational data and limited data products were collected in other areas in Florida including Orchid, Ponte Vedra, Suwannee, Panama City, and others. Data is organized by site (four primary sites and others); data collection phase with respect to the two hurricanes; and instruments or data collection method. This work included support from both the UF Center for Coastal Solutions and the NHERI RAPID facility. 
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  5. Abstract The presence of contaminants of emerging concerns (CECs) such as pharmaceuticals and personal care products, endocrine disrupting compounds (EDCs), per/poly‐fluorinated substances (PFAS), pesticides, and nanomaterials poses significant challenges to the environment and human health. This review discusses the current status of electrochemical sensing methods and their potential as low‐cost analytical platforms for the detection and characterization of emerging contaminants. Recent developments in advanced materials and fabrication techniques such as electrophoretic deposition, layer‐by‐layer deposition, roll‐to‐roll and 3D printing techniques, and the scalable manufacturing of low‐cost portable electrochemical devices are discussed. Examples of detection mechanisms, electrode modification procedures, device configuration, and their performance along with recent developments in fundamental electrochemistry, particularly nanoimpact methods, are provided to demonstrate the capabilities of these methods for the environmental monitoring of CECs. Finally, a critical discussion of future research needs, detection challenges, and opportunities is provided to demonstrate how electrochemistry can be used to advance field monitoring of these chemicals. These methods can be used as complementary or alternative methods to the currently used laboratory‐based analytical instrumentation to facilitate large‐scale studies and manage risks associated with the presence of CECs in the environment and other matrices. 
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