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In the present paper, we apply a blind fitting algorithm to model two-dimensional energy-incidence angle maps of soft x-ray resonant reflectivity measured in nanoscale epitaxial multilayers of multiferroic ε-Fe2O3 grown by pulsed laser deposition. The possibility of fitting the spectral shape of the complex refraction index across the Fe L3 absorption edge without having an initial guess about the optical constants has been demonstrated. The spectral shape fitting of the real (f1) and imaginary (f2) parts of the atomic scattering factor has been carried out by using a specially designed software utilizing OpenCL fast calculations on graphical processing units. The Kramers-Kronig relations between f1 and f2 are automatically taken into account by the fitting algorithm. A reasonable agreement between blindly generated and reference scattering factor spectra derived independently from an x-ray absorption spectroscopy experiment has been demonstrated. The blind fitting has been compared with the alternative refinement routines, in which small free variations of the reference spectral shapes (or no variations at all) have been allowed. The presented approach to the resonant x-ray reflectometry modeling makes it unnecessary to acquire the optical constant spectral shapes in advance and, thus, is especially helpful when such spectra cannot be physically measured, e.g., for a buried layer of a multilayer system. [ABSTRACT FROM AUTHOR]

Iron emissions from human activities, such as oil combustion and smelting, affect the Earth's climate and marine ecosystems. These emissions are difficult to quantify accurately due to a lack of observations, particularly in remote ocean regions. In this study, we used long‐term, near‐source observations in areas with a dominance of anthropogenic iron emissions in various parts of the world to better estimate the total amount of anthropogenic iron emissions. We also used a statistical source apportionment method to identify the anthropogenic components and their sub‐sources from bulk aerosol observations in the United States. We find that the estimates of anthropogenic iron emissions are within a factor of 3 in most regions compared to previous inventory estimates. Under‐ or overestimation varied by region and depended on the number of sites, interannual variability, and the statistical filter choice. Smelting‐related iron emissions are overestimated by a factor of 1.5 in East Asia compared to previous estimates. More long‐term iron observations and the consideration of the influence of dust and wildfires could help reduce the uncertainty in anthropogenic iron emissions estimates. Plain Language Summary: Human activities, such as smelting and oil combustion, release smoke and particles into the atmosphere. These particles often contain iron, which not only absorbs sunlight, contributing to atmospheric warming, but also serves as a nutrient for phytoplankton in various ocean regions. However, the precise extent of human‐induced iron emissions remains uncertain due to a lack of comprehensive monitoring data. In this study, we leverage a global data set of iron observations to refine our estimates of iron emissions attributed to human activities. Additionally, we examine other co‐released substances, such as carbon and nickel, to identify specific emission sources of iron. We employ statistical techniques to distinguish human‐caused iron emissions from those originating from natural sources like dust and wildfires. Moreover, we utilize iron oxide observations to constrain emissions originating from East Asia and Norway, which are estimated to originate largely from smelting emissions. Through the analysis of long‐term data sets, we provide lower and upper bounds to human‐caused iron emissions. Furthermore, we investigate the impact of reduced observation numbers and a sparse network on the range of estimated iron emissions. Our findings highlight the critical role of observation quality in accurately assessing iron emissions from human activities. Key Points: Anthropogenic total iron emissions are constrained to a factor of 3 in most global regions using long‐term aerosol observationsThe number of sites, interannual variability, and site selection filter can affect the model‐observation comparison uncertainty by 15%–50%Smelting‐related emissions are constrained to a factor of 1.5 using iron oxide observations from East Asia [ABSTRACT FROM AUTHOR]

In this study, poly(n-isopropylacrylamide) (PNIPA) has been synthesized by the free-radical polymerization method using azobisisobutyronitrile the initiator. Then, nanoparticle-PNIPA composite is prepared with magnetic iron oxide (Fe3O4) nanoparticles synthesized by co-precipitation. The thermal decomposition kinetics of synthesized PNIPA and nanocoated PNIPA have been investigated. It has been observed that nanocoated PNIPA has a more stable structure at high temperatures than synthesized PNIPA. In the newly improved model equations relate to thermal decomposition kinetics, a special solution has been made with the new approach. Moreover, the calculated activation energies of the samples have been evaluated with response surface methodology (RSM). The ratios required to synthesize nanocoated-PNIPA under the optimum conditions have been determined by RSM. The activation energy of the nanocomposite obtains when 0.3170 g PNIPA is coated with 0.048 g Fe3O4 nanoparticle is determined as 127.757 kJ/mol. In other words, nanocoating has been increased the thermal stability of the synthesized composite. Poly (n-isopropylacrylamide) has been synthesized by free radical polymerization The Fe-O stretching vibration proves the existence of nanoparticle in FTIR spectra The thermal decomposition kinetics of synthesized PNIPA and Fe3O4-PNIPA nanocomposite have been evaluated by RSM. Magnetic nanoparticle reinforcement enhances the thermal stability of PNIPA [ABSTRACT FROM AUTHOR]

The evaluation of the adsorption capacity of amine‐functionalized silica coated iron oxide magnetic particles (Fe3O4/SiO2‐NH2) as a highly recyclable adsorbent for Congo Red (CR) and Eriochrome Black T (EBT) azo‐dyes from water is reported. The Fe3O4/SiO2‐NH2 were prepared by a simple co‐precipitation method of iron oxide (Fe3O4) nanoparticles followed by silica coating on oleic acid coated Fe3O4. A series of investigation was performed to assess the various experimental parameters like contact time (0–360 min), pH (3–10), stirring speed (0–500 rpm), adsorbent dosages (0.02–0.12 g) and initial concentrations (0.02–0.15 mg mL−1) of dyes. According to the Langmuir isotherm, the maximum adsorption capacities of CR and EBT on Fe3O4/SiO2‐NH2 particles were found to be 211.86 mg g−1 and 81.98 mg g−1, respectively. In comparison, the pseudo‐second order model provided adsorption capacities of 200.40 mg g−1 for CR and 80.91 mg g−1 for EBT. Additionally, the maximum adsorption amounts of CR and EBT on Fe3O4/SiO2‐NH2 particles were 179.37 mg g−1 and 75.43 mg g−1, achieved within 300 min and 180 min at pH 3, respectively. The dye‐loaded particles were recoverable for CR and EBT removal by simple regeneration with 0.1 molL−1 NaOH solution to use the particles until more than five cycles. [ABSTRACT FROM AUTHOR]

The development of nanomaterials for dye degradation has garnered significant interest due to their efficiency, environmental benefits, and cost‐effectiveness. In this study, a nanocomposite adsorbent composed of α‐Fe2O3 coupled with carbon derived from eco‐friendly corn husk has been developed. This material effectively captured cationic dyes, Methylene Blue (MB) and Malachite Green (MG), from aqueous solutions, including industrial dye effluent from local industry. The synthesized nanocomposite demonstrated rapid removal of MB and MG from the solution without the need for additional oxidizing or reducing agents. The adsorption conditions by varying parameters such as adsorbent dose, contact time, solution pH, initial dye concentration, and temperature have been optimized. Adsorption isothermal studies indicated that the Langmuir isotherm model best explained the adsorption process. Kinetic studies revealed that the adsorption process follows a pseudo‐first‐order model for MB, while the intraparticle diffusion model is more appropriate for MG. Moreover, the nanocomposite exhibited excellent reusability and regenerability for dye adsorption. Our study showcases the effectiveness of the synthesized nanocomposite adsorbent, comprising α‐Fe2O3 integrated with carbon derived from eco‐friendly corn husk using a simple and sustainable methodology, in efficiently removing cationic dyes from textile wastewater. This approach offers a promising solution for environmental remediation. [ABSTRACT FROM AUTHOR]

The ca. 480 Ma Albești granite (Southern Carpathians, Romania) is characterized by the presence of color zoned blue quartz grains, and is part of the rather extensive European Cambro-Ordovician blue quartz landscape. The color is heat sensitive, fading at temperatures as low as 300℃, inconsistent with the thermally stable, light scattering, nanometric rutile/ilmenite inclusions cited in literature. Extensive X- and Q-band electron paramagnetic resonance (EPR) investigations were carried out, searching for distinctive features of the Albești quartz that are directly or indirectly involved in the generation of the blue coloration. The analyzed quartz grains were extracted from three granite samples of varying coloration and anisotropy, and the quartz from each rock sample was further separated into colored and colorless fractions. The paramagnetic E' and [AlO4]0 centers, as well as Mn2+ ions localized in traces of amorphous associated minerals at grain boundaries or fissure planes, were observed in all quartz samples. Broad EPR lines associated with the presence of magnetic clusters were observed in the spectra of the white quartz sample and the corresponding colorless one. Isochronal annealing up to 500℃ induced the correlated recombination of the E' and [AlO4]0 centers, the strong decrease of the Mn2+ spectrum and the formation of a minority iron oxide phase at the grain boundaries and/or fissure planes. The EPR signature was similar for the colored and the corresponding colorless quartz samples, before and after annealing, showing that the heat sensitive coloration of the Albești quartz does not directly involve the presence of paramagnetic defects and/or minority magnetic phases. [ABSTRACT FROM AUTHOR]

Analyzing transition metal XPS peaks is widely used to determine surface composition and chemistry. However, these peaks have a complex structure, which is still the subject of investigation. Fe 2p analysis is a case in point where the multiplet structure and many-electron-effects lead to peak shapes that cannot be analyzed using standard approaches. Examination of the literature reveals that one of the most widely used approaches to data reduction when processing Fe 2p3/2 spectra involves using symmetric two- or three-component peak fitting with each peak effectively acting to capture a single chemical species (chemistry fit) in the complex spectra. Herein, this approach is compared to an envelope fit approach using Biesinger multiplet components of known iron oxides to determine how effective these methods are in reproducing iron oxide composition. Mixed oxide and metal XPS Fe 2p spectra were synthesized using reference spectra collected experimentally. For the first time, the accuracy and differences between the two approaches are reported. It is demonstrated that no meaningful conclusions can be drawn using single symmetric peaks to analyze complex Fe 2p3/2 spectra, implying that a large portion of the literature is flawed. The envelope fit approach, however, is shown to provide useful information regarding oxide ratios in mixed iron oxide materials, though limitations do exist. A methodology for evaluating the quality of XPS analysis of Fe 2p3/2 spectra is proposed for benchmarking new submissions so that reviewers, authors, and editors can assess these submissions. [ABSTRACT FROM AUTHOR]

The present study focuses on the elaboration of magnetic nanocomposites by the in situ incorporation of magnetite (Fe3O4) nanoparticles (NPs) with spherical and nanoflower-like morphologies in graphitic carbon nitride (g-C3N4) sheets using two different synthetic routes. Nanomaterials are characterized by TEM, SEM, XRD, FTIR, BET, zetametry, vibrating sample magnetometry, and UV–vis absorption spectroscopy. The decoration of the carbon nitride matrix with the magnetic NPs enhanced optical and textural properties. The influence of the morphology of the magnetic NPs on the adsorptive and photocatalytic properties of the nanocomposites under different pH conditions (4.5, 6.9, and 10.6) was assessed from batch tests to remove methylene blue (MB) from aqueous solutions. In extreme pH conditions, the nanocomposites exhibited lower or equivalent MB removal capacity compared to the pure g-C3N4. However, at neutral medium, the nanocomposite with incorporated Fe3O4 nanoflowers showed a significantly higher removal efficiency (80.7%) due to the combination of a high adsorption capacity and a good photocatalytic activity in this pH region. The proposed nanocomposite is a promising alternative to remove cationic dyes from water by magnetic assistance, since no pH adjustment of the polluted effluent is required, reducing costs and environmental impact in the dyeing industry. [ABSTRACT FROM AUTHOR]

Predicting the liberation distribution of minerals in comminuted ore particles is one of the fundamental problems in mineral processing. However, there is still no widely accepted liberation model due to the complexity of the mineral fracture mechanism. In this study, the shape constants of the cumulative beta distribution were further optimized based on the investigation of the liberation distribution and fracture mechanism of iron oxide minerals in three types of iron ores with different grain sizes by locked-cycle grinding and batch grinding to model the liberation distribution of iron oxide minerals with different grinding methods. The results showed that the liberation distribution of iron oxide minerals in the three types of iron ores with locked-cycle grinding and batch grinding was related to intergranular fracture proportion and the closeness of ore particle size and mineral grain size. By relating the shape constants of cumulative beta distribution to ore particle size, mineral grain size, and the proportion of intergranular fracture, the developed liberation model well predicted the liberation distribution of iron oxide minerals with different grinding methods and its coefficient of determination (R2) was between 0.85–0.93. [ABSTRACT FROM AUTHOR]

This study successfully synthesized Fe2O3@rGO nanocrystals using a straightforward sol-gel method in a pigskin-gel (gelatin type A) environment. The fabricated nanocomposites include Fe2O3-linked nanosheets in a reduced graphene oxide-like double tetrahedral pyramid (DTP) structure and Fe2O3 nanocrystals resembling Cheetos puffs (CPs). The Fe2O3@rGO material was characterized through a variety of analytical techniques, including X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, elemental mapping, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, Raman spectroscopy, vibrating sample magnetometer, nitrogen physisorption, and electrochemical impedance spectroscopy. The photocatalytic efficiency of Fe2O3 and Fe2O3@rGO samples in demineralizing rhodamine B in an aqueous solution was thoroughly evaluated. Remarkably, the Fe2O3@rGO composites exhibited significantly enhanced photocatalytic activity and degradation efficiency compared to pure Fe2O3 nanocrystals. The improved performance can be attributed to effective electron transport between the reduced graphene oxide and the semiconductors, effectively reducing electron-hole recombination. Additionally, the Fe2O3@rGO nanocrystals demonstrated excellent magnetic properties, enabling easy separation and recovery after five cycles of reusability testing. These findings highlight the promising potential of this magnetic nano photocatalyst for efficient and sustainable wastewater treatment applications, particularly in the degradation of rhodamine B. Highlights: In the presence of pigskin gel, the synthesis of Fe2O3 nanocrystals (NCs) resembling Cheetos puffs (CPs) were carried out. In the presence of pigskin gel as a reducing agent, Fe2O3 nanocrystals with double tetrahedral pyramidal geometry (DTP) attached to reduced graphene oxide (rGO) nanosheets were obtained. Fe2O3@rGO:DTP Showed improved responsiveness compared to the pure Fe2O3:CPs for the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

The efficient graphene coated iron oxide (GCIO) nanoadsorbent was prepared for removal of various ions, viz., Cr(VI), Pb(II), and As(III), by coating graphene onto the iron oxide surfaces taken as a base material. The as-prepared nanoadsorbent was further characterized by several analytical techniques such as Fourier transform infrared (FTIR) spectroscopy, energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Raman spectroscopy, Differential scanning calorimetry (DSC), and Zeta-potential measurements, respectively. These techniques provided valuable information about the nanoadsorbent and confirmed the interactions between Cr6+, Pb2+, and As3+ ions and the nanoadsorbent. The effect of concentration of adsorbate solution, contact time between adsorbate–adsorbent, and flow rate of adsorbate were studied using a sensitive, simple, and selective spectrophotometric method that enabled quantification of Cr6+, Pb+2, and As3+ ions, respectively. Various modeling of breakthrough curves was applied for monitoring progress of the adsorption process and the results showed that the three metal ions followed second order kinetic model thus confirming that GCIO is an excellent, effective, and economic adsorbent. [ABSTRACT FROM AUTHOR]

Cancer is a global issue and hence various efforts are being made. Iron oxide is considered a significant biochemical agent in the biomedical arena for cancer treatment. Marine macroalgae-mediated iron oxides especially, magnetite (Fe3O4) nanoparticles (NPs) are a prospective alternative to diagnose and treat cancer owing to their fluorescent and magnetic properties. We intend to appraise the usability of the aqueous extract of Rosenvingea intricata (R. intricata) in Fe3O4 NPs synthesis and to study their cytotoxic effects against human hepatocarcinoma (Hep3B) and pancreatic (PANC1) cancer cells. In the present study, R. intricata were collected from the coastal region of South Andaman, India. Aqueous extracts of R. intricata were utilized to synthesize Fe3O4 NPs via the co-precipitation method. Phycosynthesized Fe3O4 NPs exhibited wide peak at 400–600 nm from ultraviolet–visible diffused reflectance spectroscopic analysis which validated the formation of NPs. Band edge emission peak at 660 nm in fluorescent spectra confirmed the quantum confinement in Fe3O4 NPs. Fourier transform infrared spectroscopy confirmed the role of R. intricata as a capping and reducing agent with functional groups such as O–H, C–H, C=O, N=O, C=C, C–O, C–N, and C–S arising from amino acids, polysaccharides, aliphatic hydrocarbons, esters, amides, lignins, alkanes, aliphatic amines, and sulfates. Physicochemical properties such as crystallite size (14.36 nm), hydrodynamic size (84.6 nm), irregular morphology, elemental composition, particle size (125 nm), crystallinity, and saturation magnetization (0.90007 emu/g) were obtained from x-ray diffractometer, dynamic light scattering, scanning electron microscopy, energy dispersive x-ray spectrometer, high-resolution transmission electron microscopy, selected area electron diffraction and vibrating sample magnetometer techniques, respectively. The cell viability showed dose-dependent cytotoxic effects and enhanced the apoptosis against Hep3B and PANC1 cancer cells. R. intricata extract capped Fe3O4 NPs could be the most appropriate and effective nanomaterial for cancer treatment and management. [ABSTRACT FROM AUTHOR]

This study focuses on developing machine learning models to detect subtle alterations in hepatocyte chromatin organization due to Iron (II, III) oxide nanoparticle exposure, hypothesizing that exposure will significantly alter chromatin texture. A total of 2000 hepatocyte nuclear regions of interest (ROIs) from mouse liver tissue were analyzed, and for each ROI, 5 different parameters were calculated: Long Run Emphasis, Short Run Emphasis, Run Length Nonuniformity, and 2 wavelet coefficient energies obtained after the discrete wavelet transform. These parameters served as input for supervised machine learning models, specifically random forest and gradient boosting classifiers. The models demonstrated relatively robust performance in distinguishing hepatocyte chromatin structures belonging to the group exposed to IONPs from the controls. The study's findings suggest that iron oxide nanoparticles induce substantial changes in hepatocyte chromatin distribution and underscore the potential of AI techniques in advancing hepatocyte evaluation in physiological and pathological conditions. [ABSTRACT FROM AUTHOR]

Although spinel ferrite nanostructures with adjustable magnetic properties have long been considered for different applications such as microwave, biomedical and magnetic memory devices, detailed magnetic behavior and structural properties of manganese-cobalt ferrites are yet to be investigated and understood. Here, cobalt ferrite nanoparticles (NPs) substituted with manganese (Co1–x Mnx Fe2O4); 0 ≤ x ≤ 1) are synthesized using a co-precipitation method followed by annealing at 800 °C. X-ray diffraction patterns confirm the formation of cubic spinel structure, which is accompanied with α-‌ Fe 2 O 3 secondary phase when increasing the manganese content of NPs, as also observed using field emission scanning electron microscopy. Hysteresis loop measurements demonstrate an increasing trend of magnetic properties with increasing x, leading to maximum values of saturation magnetization (Ms= 65 emu/g) and coercivity (Hc= 1815 Oe) for Co 0.8 Mn 0.2 Fe 2 O 4 NPs. Meanwhile, first-order reversal curve (FORC) analysis manifests distinct soft and hard magnetic phases induced by the slight enhancement in the manganese content. The magnetic hardening of single domain manganese-cobalt ferrite NPs at room temperature is revealed by an increase in FORC coercivity up to 2480 Oe, being about 90% higher than that for pure cobalt ferrite NPs. Further increasing x weakens magnetic properties, minimizing M s and H c to 10 emu/g and 35 Oe when Mn completely substitutes Co in the spinel ferrite structure. In this case, FORC analysis shows suppressed inter-particle magnetostatic interactions and predominant superparamagnetic contribution for MnFe 2 O 4 NPs. [ABSTRACT FROM AUTHOR]

Fluorinated arylborane‐based Lewis acid catalysts have shown remarkable activity and serve as ideal examples of transition metal‐free catalysts for diverse organic transformations. However, their homogeneous nature poses challenges in terms of recyclability and separation from reaction mixtures. This work presents an efficient technique for the heterogenization of boron Lewis acid catalysts by anchoring Piers' borane to allyl‐functionalized iron oxide. This catalyst demonstrates excellent activity in the hydrosilylation of imines and the reductive amination of carbonyls using various silanes as reducing agents under mild reaction conditions. The catalyst exhibits broad tolerance towards a wide range of functional substrates. Furthermore, it exhibits good recyclability and can be easily separated from the products using an external magnetic field. This work represents a significant advance in the development of sustainable heterogenous metal‐free catalysts for organic transformations. [ABSTRACT FROM AUTHOR]

Photocatalysis is essential for wastewater cleanup and clean energy, and in this current study, we have synthesized nanomaterials (iron oxide-based) for photocatalytic pollution degradation and hydrogen production. The performance of aluminium oxide/ferric oxide (Al2O3/Fe2O3), samarium oxide/ferric oxide (Sm2O3/Fe2O3) and yttrium oxide/ferric oxide (Y2O3/Fe2O3) were compared for the production of hydrogen (H2) and degradation of dye under natural sunlight. Various characterisation equipment was used to characterize these photocatalysts’ structure, morphology, elemental content, binding energy and band gap. The hydrogen recovery efficiency of iron oxide-based photocatalysts from sulphide-containing wastewater is assessed. Y2O3/Fe2O3 has shown the highest hydrogen production of 340 mL/h. The influence of operating factors such as sulphide ion concentration, catalyst quantity, and photocatalyst photolytic solution volume on hydrogen production is studied. The optimal values were 0.25 M, 0.2 g/L, and 1L, respectively. The developed photocatalyst passed multiple cycles of stability testing. Fe2O3 has shown the highest Rhodamine B (RhB) dye degradation efficiency of 94% under visible light. [ABSTRACT FROM AUTHOR]

High ammonia concentrations in anaerobic degradation systems cause volatile fatty acid accumulation and reduced methane yield, which often derive from restricted activity of syntrophic acid-oxidising bacteria and hydrogenotrophic methanogens. Inclusion of additives that facilitate the electron transfer or increase cell proximity of syntrophic species by flocculation can be a suitable strategy to counteract these problems, but its actual impact on syntrophic interactions has yet to be determined. In this study, microbial cultivation and molecular and microscopic analysis were performed to evaluate the impact of conductive (graphene, iron oxide) and non-conductive (zeolite) additives on the degradation rate of acetate and propionate to methane by highly enriched ammonia-tolerant syntrophic cultures derived from a biogas process. All additives had a low impact on the lag phase but resulted in a higher rate of acetate (except graphene) and propionate degradation. The syntrophic bacteria 'Candidatus Syntrophopropionicum ammoniitolerans', Syntrophaceticus schinkii and a novel hydrogenotrophic methanogen were found in higher relative abundance and higher gene copy numbers in flocculating communities than in planktonic communities in the cultures, indicating benefits to syntrophs of living in close proximity to their cooperating partner. Microscopy and element analysis showed precipitation of phosphates and biofilm formation in all batches except on the graphene batches, possibly enhancing the rate of acetate and propionate degradation. Overall, the concordance of responses observed in both acetate- and propionate-fed cultures highlight the suitability of the addition of iron oxide or zeolites to enhance acid conversion to methane in high-ammonia biogas processes. Key points: • All additives promoted acetate (except graphene) and propionate degradation. • A preference for floc formation by ammonia-tolerant syntrophs was revealed. • Microbes colonised the surfaces of iron oxide and zeolite, but not graphene. [ABSTRACT FROM AUTHOR]

In biogeochemical phosphorus cycling, iron oxide minerals are acknowledged as strong adsorbents of inorganic and organic phosphorus. Dephosphorylation of organic phosphorus is attributed only to biological processes, but iron oxides could also catalyze this reaction. Evidence of this abiotic catalysis has relied on monitoring products in solution, thereby ignoring iron oxides as both catalysts and adsorbents. Here we apply high-resolution mass spectrometry and X-ray absorption spectroscopy to characterize dissolved and particulate phosphorus species, respectively. In soil and sediment samples reacted with ribonucleotides, we uncover the abiotic production of particulate inorganic phosphate associated specifically with iron oxides. Reactions of various organic phosphorus compounds with the different minerals identified in the environmental samples reveal up to ten-fold greater catalytic reactivities with iron oxides than with silicate and aluminosilicate minerals. Importantly, accounting for inorganic phosphate both in solution and mineral-bound, the dephosphorylation rates of iron oxides were within reported enzymatic rates in soils. Our findings thus imply a missing abiotic axiom for organic phosphorus mineralization in phosphorus cycling. Iron oxides serve as both adsorbents and catalysts to generate inorganic phosphorus from organic phosphorus in environmental matrices. This abiotic dephosphorylation, which is comparable to enzymatic rates, is a missing piece in phosphorus cycling. [ABSTRACT FROM AUTHOR]

Water contaminated with arsenic presents serious health risks, necessitating effective and sustainable removal methods. This article proposes a method for removing arsenic from water by impregnating biochar with iron oxide (Fe2O3) from brown seaweed (Sargassumpolycystum). After the seaweed biomass was pyrolyzed at 400 °C, iron oxide was added to the biochar to increase its adsorptive sites and surface functional groups, which allowed the binding of arsenic ions. Batch studies were conducted to maximize the effects of variables, including pH, contact time, arsenic concentration, and adsorbent dosage, on arsenic adsorption. The maximum arsenic adsorption efficiency of 96.7% was achieved under optimal conditions: pH 6, the adsorbent dosage of 100 mg, the initial arsenic concentration of 0.25 mg/L, and a contact time of 90 min. Langmuir and Freundlich's isotherms favored the adsorption process, while the kinetics adhered to a pseudo-second-order model, indicating chemisorption as the controlling step. Column studies revealed complete saturation after 200 min, and the adsorption behavior fits both the Adams–Bohart and Thomas models, demonstrating the potential for large-scale application. The primary mechanism underlying the interaction between iron-modified biochar and arsenic ions is surface complexation, enhanced by increased surface area and porosity. This study highlights the significant contribution of iron-modified biochar derived from macroalgae as an effective and sustainable solution for arsenic removal from water. [ABSTRACT FROM AUTHOR]

Aqueous Sn‐air batteries are attracting a great deal of interest in recent years due to the ultra‐high safety, low cost, dendrite‐free and highly reversible Sn anode. However, the slurry oxygen reduction/evolution reaction (ORR/OER) kinetics on the air cathodes seriously affect the Sn‐air battery performances. Although various advanced catalysts have been developed, the charge overpotentials (~1000 mV) of these Sn‐air batteries are still not satisfactory. Herein, iron oxide (Fe2O3) modified titanium dioxide (TiO2) nanorods with heterogeneous structure are firstly synthesized on Ti mesh (Fe2O3@TiO2/Ti), and the obtained Fe2O3@TiO2/Ti films are further applied as catalytic electrodes for Sn‐air batteries. The core–shell heterogeneous structure of Fe2O3@TiO2/Ti can effectively facilitate the conversion of electrochemical intermediates and separation of photo‐excited electrons and holes to activate oxygen‐related reaction processes. Density functional theory (DFT) and experimental results also confirm that Fe2O3@TiO2/Ti can not only act as the electrocatalysts to improve ORR/OER properties, but also exhibit the superior photo‐catalytic activity to promote charging kinetics. Hence, the Fe2O3@TiO2/Ti‐based Sn‐air batteries show ultra‐low overpotential of ~40 mV, excellent rate capability and good cycling stability under light irradiation. This work will shed light on rational photo‐assisted catalytic cathode design for new‐type metal‐air batteries. [ABSTRACT FROM AUTHOR]

The Cr(VI) removal efficiency of a Brazilian Oxisol collected from the A horizon (15.2% iron oxides, 4.6% organic matter, pH 4.3) was assessed and compared with synthesized iron minerals (SM), to mitigate contamination as a nature-based solution. Batch tests revealed that Cr(VI) removal efficiency was higher and faster for SM than for Oxisol: to remove ∼ 100% Cr(VI) from a solution containing 5 mg L− 1Cr(VI), SM took 24 h, while for the same concentration Oxisol removed 80% Cr(VI) in 30 days. At a higher concentration (30 mg L− 1), Cr(VI) removal efficiency dropped to 90% in 24 h for SM and 22% in 30 days for Oxisol. The Cr(VI) removal of Oxisol and SM fitted, respectively, to the pseudo-first and pseudo-second order, reflecting the way Cr(VI) is removed - by adsorption for SM (since pHPZC> pHsolution) and by reduction to Cr(III) for Oxisol organic matter. To simulate a contamination event, Oxisol was incubated with 300 mg L− 1 of Cr(VI) for 5, 10 and 30 days, followed by sequential extraction. The results of this test revealed that all the chromium was reduced to Cr(III) in all the time periods, and was mostly bound to the less mobile fractions of the soil: organic matter (75–85%), iron oxide/hydroxide (∼ 15%), and the residual fraction (< 5%); and only 5–10% was bound to the exchangeable fraction (more mobile). Although Cr(VI) is better adsorbed by SM, in Oxisol chromium is found in the less toxic form (trivalent) and bound to the less mobile fractions, promoting a more sustainable solution. [ABSTRACT FROM AUTHOR]

Structured marine clay is commonly encountered in offshore engineering projects and engineers are concerned about its impact on the engineering properties of marine clay as well as its correlation with index properties. Current research has emphasized the role of soil structure in these aspects of marine clay. In this study, we investigated the influence of depositional environment and oxidation-induced evolution of clay microstructure on the formation of clay structure in structured clay from Zhanjiang area, a coastal city located in South China. The distinct soil structure observed in marine-terrigenous clay deposited under different environments exhibited sensitivity ranging from 1.6 to 8.9 at varying moisture content levels. The wide range of sensitivity observed in structured marine-terrigenous clay was attributed to free iron oxide derived from siderite present in an acidic environment. Compared to other regions, Zhanjiang marine clay demonstrated favorable mechanical properties but poor physical properties due to its unique clay structure characteristics. Based on these findings, we proposed a modified approach for correlating index properties with engineering properties that yielded good predictions. [ABSTRACT FROM AUTHOR]

Iron‐based materials are considered potential anode materials for lithium‐ion batteries thanks to their low cost, abundancy, non‐flammability, good safety, environmental benignity, and high specific capacity. Here, a series of calcium iron oxides materials having brownmillerite structure (i. e., Ca2Fe2‐xMxO5, where M=Mn, Ni and Cu and x=0 and 0.1) has been extensively studied for their use as conversion anodes in lithium cell. In particular, a mechanochemical approach has been used either to synthesize the samples and to prepare electrodes for the tests in lithium cell. Ca2Fe2O5 based electrodes proved excellent performance in lithium cell, approaching the theoretical capacity and being stable upon prolonged cycling (529 mAh g−1 at C/10 and a capacity retention of 81 % after 100 cycles). Through the use of ex‐situ diffraction measurements, we have analyzed the conversion mechanism and proved the partial reversibility of its electrochemical reaction. Also, the incorporation of dopants into the structure of calcium iron oxide resulted in further improvement of its electrochemical performance as is the case of Mn doped sample that show a considerable specific capacity of 567 mAh g−1 and the capacity retention is almost 99 % after 100 cycles. [ABSTRACT FROM AUTHOR]

This paper presents the fabrication and characterization of plane capacitors utilizing magnetodielectric materials composed of magnetizable microfibers dispersed within a silicone oil matrix. The microfibers, with a mean diameter of about 0.94 μ m, comprise hematite (α -Fe2O3), maghemite (γ -Fe2O3), and magnetite (Fe3O4). This study investigates the electrical behavior of these capacitors under the influence of an external magnetic field superimposed on a medium-frequency alternating electric field, across four distinct volume concentrations of microfibers. Electrical capacitance and resistance measurements were conducted every second over a 60-s interval, revealing significant dependencies on both the quantity of magnetizable phase and the applied magnetic flux density. Furthermore, the temporal stability of the capacitors' characteristics is demonstrated. The obtained data are analyzed to determine the electrical conductance and susceptance of the capacitors, elucidating their sensitivity to variations in microfiber concentration and magnetic field strength. To provide theoretical insight into the observed phenomena, a model based on dipolar approximations is proposed. This model effectively explains the underlying physical mechanisms governing the electrical properties of the capacitors. These findings offer valuable insights into the design and optimization of magnetodielectric-based capacitors for diverse applications in microelectronics and sensor technologies. [ABSTRACT FROM AUTHOR]

A diatomite-modified Fe2O3 (Fe2O3/Dia) catalyst was prepared to catalyze the ozonation degradation of sulfachloropyridazine sodium (SPDZ). The chemical oxygen demand (COD) was used as the index of pollutant degradation. The catalytic ozonation experiment showed that the COD removal rate of SPDZ was 87% under Fe2O3/Dia catalysis, which was much higher than that obtained when using Fe2O3 as the catalyst. The characteristics of the Fe2O3/Dia catalyst were investigated, and the successful synthesis of the Fe2O3/Dia composite catalyst was proved by XRD, XPS, SEM, FTIR, BET and other characterization methods. The catalytic mechanism of degradation by ozone with Fe2O3/Dia was analyzed. According to free-radical trapping experiments and an in situ electron paramagnetic spectrometer characterization analysis, the main oxidizing species in the catalytic Fe2O3/Dia ozone system is ·OH. The intermediates in the degradation process of SPDZ were detected and analyzed in detail by liquid chromatography-coupled mass spectrometry. The degradation mechanism and three degradation paths of SPDZ were proposed. [ABSTRACT FROM AUTHOR]

Fe2O3 loaded in the interlayer of hectorite was synthesized using a steam-assisted one-pot method to replace the traditional high-temperature and high-pressure hydrothermal method. The samples were characterized by means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and N2 adsorption–desorption isotherms. Fe2O3/hectorite had a layered hectorite structure. Due to the insertion of Fe2O3, the interlayer spacing increased and had a large specific surface area and pore size, benefiting catalytic reactions. Fe2O3/hectorite was used as a catalyst to degrade phenol in wastewater via the Fenton reaction. With this catalyst, the optimal Fenton reaction conditions were determined with an orthogonal test: pH, 3; temperature, 60 °C; and catalyst dosage, 0.5 g dm−3. Under these optimal reaction conditions, the degradation rate of phenol (200 mg dm–3) was 99.27% in 3 h. After five cycles, the degradation rate reached 95.72%, indicating the excellent reusability of this catalyst. In the temperature range 303–330 K, the catalytic degradation kinetics were studied as a pseudo-first-order reaction, and the apparent activation energy was 30.71 kJ/mol. [ABSTRACT FROM AUTHOR]

Polymeric carbon nitride (PCN) is a kind of polymeric semiconductor that is widely popular in photocatalysis-related energy and environmental fields. However, the photocatalytic activity is still limited due to its poor conductivity and low charge separation efficiency. In this work, benzene rings were introduced to adjust the electronic structure of PCN, and then a PCN-based all-solid Z-scheme heterojunction was fabricated by combing multiwall carbon nanotubes (CNTs) and ferric oxide through precipitation and the in situ deposit method. Upon optimizing the ratio between PCN, CNTs, and Fe2O3, (PCN:CNTs:Fe2O3 = 10:1:3 by weight), the composites expressed superior photocatalytic degradation activity towards methylene blue (MB) and crystal violet (CV) compared with pristine PCN and Fe2O3. The MB degradation percentage achieved 90% in 75 min, and the CV up to 99.6% within 50 min. The Z-scheme mechanism was verified by band alignment and metal selective deposition. The CNTs in the heterojunction played the role of an electron shuttling mediator and hence improved charge separation efficiency. This work provides ideas for the construction of polymer-inorganic all-solid Z-scheme photocatalysts for practical applications. [ABSTRACT FROM AUTHOR]

Textile industry effluents contain several hazardous substances, such as dye-containing effluents, which pose environmental and aesthetic challenges. Presently, the microbial-based remediation process is in use. This study investigated the application of ferrous–ferric oxide (Fe3O4) nanoparticles, a readily formulated nanoadsorbent, to remove scattered dye molecules from industrial effluents. The ferrous–ferric oxide nanoparticles were prepared using a chemical co-precipitation method. The nanoparticles had 26.93 emu g−1 magnetization, with sizes smaller than 20 nm, and possessed a highly purified cubic spinel crystallite structure. The catalytic activity of the iron oxide depended on the dose, photocatalytic enhancer, i.e., H2O2 level, pH of the reaction medium, and dye concentration. We optimized the Fenton-like reaction to work best using 1.0 g/L of ferrous–ferric oxide nanoparticles, 60 mM oxalic acid at pH 7.0, and 60 ppm of dye. Iron oxides act as photocatalysts, and oxalic acid generates electron–hole pairs. Consequently, higher amounts of super-radicals cause the rapid degradation of dye and pseudo-first-order reactions. Liquid chromatography–mass spectrometry (LC-MS) analysis revealed the ferrous–ferric oxide nanoparticles decolorized and destroyed Disperse Red 277 in 180 min under visible light. Hence, complete demineralization is observed using a photo-Fenton-like reaction within 3 h under visible light. These high-capacity, easy-to-separate next-generation adsorption systems are suggested to be suitable for industrial-scale use. Ferrous–ferric oxide nanoparticles with increased adsorption and magnetic properties could be utilized to clean environmental pollution. [ABSTRACT FROM AUTHOR]

The application of iron oxide quantum dots (IOQDs) in this study led to the development of a straightforward, easy, and selective approach for cytosine sensing. To examine the capability of IOQDs in detecting nucleobases, attempts have been made to gain insight into the characteristics of IOQDs, including UV/Vis spectroscopic analysis, infrared spectroscopy, fluorescence spectroscopy, transmission electron microscopy, and powder‐XRD. We introduced IOQDs with a mean particle size distribution of 5.71 ± 0.08 nm for detecting cytosine by harnessing a turn‐on fluorescence phenomenon. The fostering fluorescence response of IOQDs was triggered in the presence of cytosine. In comparison, the presence of other nucleobases did not further induce the fluorescence signal of IOQDs. It was concluded that the hydrogen bonding bridging the carboxylate and hydroxyl groups on the surface of QDs with the amine groups of cytosine results in the elevation of IOQDs fluorescence. [ABSTRACT FROM AUTHOR]

Ferrites were prepared using the oxide method with strontium carbonate (SrCO3), zinc oxide (ZnO), cobalt trioxide (CO3O4), and iron oxide (Fe2O3) as raw materials. The effects of sintering temperature on the phase composition, microstructure, particle size and porosity, intrinsic coercivity Hcj, saturation magnetization Ms and electromagnetic parameters of W-type ferrite absorbent were studied. The results show that W-type ferrite is not formed when the sintering temperature is 1 125 °C. When the sintering temperature is 1 175 °C, lamellar W-type ferrite is formed. At 1 225 °C and 1 275 °C, the prepared W-type ferrite absorbent shows better absorbing properties. [ABSTRACT FROM AUTHOR]

To improve the biocompatibility and bioactivity of biodegradable iron-based materials, nanostructured surfaces formed by metal oxides offer a promising strategy for surface functionalization. To explore this potential, iron oxide nanotubes were synthesized on pure iron (Fe) using an anodic oxidation process (50 V–30 min, using an ethylene glycol solution containing 0.3% NH4F and 3% H2O, at a speed of 100 rpm). A nanotube layer composed mainly of α-Fe2O3 with diameters between 60 and 70 nm was obtained. The effect of the Fe-oxide nanotube layer on cell viability and morphology was evaluated by in vitro studies using a human osteosarcoma cell line (SaOs-2 cells). The results showed that the presence of this layer did not harm the viability or morphology of the cells. Furthermore, cells cultured on anodized surfaces showed higher metabolic activity than those on non-anodized surfaces. This research suggests that growing a layer of Fe oxide nanotubes on pure Fe is a promising method for functionalizing and improving the cytocompatibility of iron substrates. This opens up new opportunities for biomedical applications, including the development of cardiovascular stents or osteosynthesis implants. [ABSTRACT FROM AUTHOR]

Epsilon iron oxide (ϵ‐Fe2O3) and magnetoplumbite barium ferrite (BaFe12O19) are well‐known hard ferrites. For one synthesis method of ϵ‐Fe2O3, combining reverse‐micelle and sol‐gel techniques, Ba ions are used to accelerate the formation of nanorod‐shaped ϵ‐Fe2O3. On the other hand, in synthesis of BaFe12O19 both Ba and Fe ions are used to form the final product. However, the coexistence of these two ferrites has not been reported by any synthesis. Herein, we investigated the effect of Ba ions on the final product for the synthesis combining reverse‐micelle and sol‐gel techniques. At a low Ba ion ratio of [Ba]/[Fe]=0.2, ϵ‐Fe2O3 nanorods are formed, while at higher Ba ion ratios ([Ba]/[Fe]=0.4, 1, 2), BaFe12O19 appears. The phase diagram at 1000 °C shows that at a Ba ion ratio of [Ba]/[Fe]=1, the ratio of ϵ‐Fe2O3 and BaFe12O19 is almost 1 : 1. The diagram shows intermediates between these two phases do not form, indicating a phase separation of ϵ‐Fe2O3 and BaFe12O19. During the sintering process of this synthesis, initially perovskite‐type Ba2Fe2O5 and γ‐Fe2O3 nanoparticles form. Then, in areas where γ‐Fe2O3 nanoparticles are gathered around Ba2Fe2O5 and react, BaFe12O19 is formed, whereas in areas lacking Ba2Fe2O5, ϵ‐Fe2O3 nanorods are formed within Ba‐ion containing silica glass. [ABSTRACT FROM AUTHOR]

In the field of photocatalysis, heterojunction photocatalysts have garnered a lot of attention due to their high‐efficiency interfacial charge‐transfer property and their nanoarchitecture. Herein, GdFeO3/WS2 is successfully synthesized by the in‐situ growth method and holds significant catalytic properties and efficient degradation for tetracycline. Using WS2 as a co‐catalyst could reduce e‐ and h+ recombination, improving GdFeO3's photocatalytic performance. The GdFeO3/WS2 possesses a bandgap of 1.9 eV, 178.9 m2 g−1 specific surface area, 0.2 nm pore size, and a lifespan of 6 ns. The optimal GdFeO3/WS2 photocatalyst exhibits a maximum removal of 96.2 % at a tetracycline concentration of 10 mg/L, a pH of 3, and 40 mg of photocatalyst in an irradiation time of 90 min. Tetracycline has a higher photocatalytic efficiency in visible light (96.2 %) than in sunlight (72.6 %). Trapping tests revealed that the major reactive species for tetracycline removal in an aqueous solution are ⋅⋅OH, and ⋅⋅O2‐. The recycle experiment shows no deactivation of the GdFeO3/WS2 photocatalyst after 5 recycles. This study sheds light on the rational design of the GdFeO3/WS2 photocatalyst as a potential material for treating wastewater. [ABSTRACT FROM AUTHOR]

To address the problem of suboptimal performance in deep eutectic solvents displayed by traditional TiO2 photoelectrodes and Cu2O photoelectrodes that have undergone simplistic modifications that result in a mismatch with battery discharge capacity, a method combining hydrothermal and dip-coating techniques was developed to create a Fe2O3-CuO heterojunction structure on the FTO surface. Then, the impact of the heterojunction structure on the performance of solar flow batteries was investigate in this study. The experimental findings reveal that the formation of the heterojunction structure effectively mitigates the recombination rate of photogenerated carriers within the photoelectrode. Furthermore, by meticulously adjusting the CuO loading, the harmonious balance between charging and discharging currents was achieved, thereby enhancing the overall performance of the solar redox flow batteries. In comparison to standalone Fe2O3 photoelectrodes, this innovative approach significantly broadens the spectrum of sunlight utilization. Notably, the fabricated Fe2O3/CuO-2 photoelectrode demonstrates a remarkable photocharging performance, far surpassing both Fe2O3 photoelectrodes and commercial TiO2 photoelectrodes. Specifically, the Fe2O3/CuO-2 photoelectrode boosts an average current density of 598.68 μA∙cm−2, with its charging current density being 2.74 and 5.15 larger, respectively, than that of the Fe2O3 and commercial TiO2 photoelectrodes. [ABSTRACT FROM AUTHOR]

Fe2O3/g-C3N4 nano-heterostructures for photocatalytic degradation of NOR (norfloxacin) were successfully prepared by combining co-precipitation and calcination methods. The g-C3N4, Fe2O3, and different composite ratios of Fe2O3/g-C3N4 (FeCNs) were characterized by XRD, SEM, XPS, UV-vis DRS, PL, and electrochemical tests, and the mechanism of photocatalytic degradation of NOR was analyzed. The results indicated that the semiconductor was attached to the surface of g-C3N4 in the form of α-Fe2O3 crystal with good crystalline structure. The composite of Fe2O3 with g-C3N4 increased the specific surface area of the material, effectively reduced the band gap, strengthened the photogenerated e−/h+ pair separation, and improved the photocatalytic performance of the composite. The photocatalytic degradation of NOR was consistent with the quasi-primary reaction kinetic model. Among them, FeCN-25wt% showed the optimal photocatalytic degradation of NOR (72.3%) with the largest degradation rate (k = 0.00900 min−1). The Fe2O3/g-C3N4 composite structure is inferred to be a Z-type heterojunction. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) is growing into a major public health crisis worldwide. The reducing alternatives to conventional agents starve for novel antimicrobial agents. Due to their unique magnetic properties and excellent biocompatibility, iron oxide nanoparticles (IONPs) are the most preferable nanomaterials in biomedicine, including antibacterial therapy, primarily through reactive oxygen species (ROS) production. IONP characteristics, including their size, shape, surface charge, and superparamagnetism, influence their biodistribution and antibacterial activity. External magnetic fields, foreign metal doping, and surface, size, and shape modification improve the antibacterial effect of IONPs. Despite a few disadvantages, IONPs are expected to be promising antibacterial agents of a new generation. [ABSTRACT FROM AUTHOR]

The Washan iron deposits in Ningwu district contain different magma-related genetic natures, including magmatic, magmatic–hydrothermal and hydrothermal types, and their ore-forming processes remain a subject of debate. To elucidate the ore-forming processes of iron ores from Washan, we present textural, major element analytical, and thermal data of magnetites from various ore bodies in Washan, probing the crystallization conditions and subsequent formation sequence of magnetites. SEM analysis with back-scattered electron (BSE) imaging reveals diverse magnetite textures, including mineral inclusions, exsolution lamellae, and recrystallization features, reflecting the transitional environment from magmatic to hydrothermal. Based on Ti, V, and Cr compositions of magnetite from different ore bodies, two distinct evolution trends of genetic processes are identified, including evolution paths from porphyry-type to IOA- and IOCG-type magnetite. High-resolution WDS mapping highlights the intensifying alterations during this process. Calculated magnetite crystallization temperatures among different types of magnetite range from 597 °C to 378 °C, suggesting a cooling trend from porphyry-type magnetite (~558 °C) to IOA-type magnetite (~515–439 °C) and IOCG-type magnetite (~378 °C). These results underscore the significant role of magma-derived hydrosaline liquids and vapors in the formation of iron ores from Washan, where variations in the salinity of ore-forming fluids lead to different evolutionary paths for subsequent generations of magnetite. The metallogenic model of the Washan iron deposit suggests that highly saline, iron-rich fluids connect the varying geneses of magnetite, transitioning from deeply formed porphyry-type magnetite to IOA- or IOCG-type magnetite generated in the subaerial zone. [ABSTRACT FROM AUTHOR]

An electrochemical immunosensor was designed and fabricated for the purpose of sensing the carcinoembryonic antigen (CEA) biomarker. The immunosensor utilized a novel approach for surface modification with a composite comprising Fe3O4 nanoparticles decorated on carboxyl functionalized multi-walled carbon nanotubes (COOH-MWCNTs). This distinctive surface tailoring of the glassy carbon electrode (GCE), amplified signals and facilitated electron transfer. The MWCNTs with COOH groups served as an excellent substrate for electrode modification, enabling the formation of a sandwich-like structure by binding to anti-CEA antibody. Additionally, Fe3O4 nanoparticles played a crucial role in electron transfer facilitation. The presence of HRP conjugated with the anti-CEA antibody triggered the reduction of H2O2 in the electrochemical system of the sensor, resulting in an augmentated current. The concentration of CEA was directly proportional to the immunosensor analytical performance. The immunosensor demonstrated a suitable linear range from 0.005 ng mL−1 to 2.5 ng mL−1, with a limit of detection (LOD) of 0.3 pg mL−1. Notably, this immunosensor demonstrated exceptional reproducibility and stability, showcasing its suitability for measuring CEA in both real serum samples. These promising outcomes establish an overview for the adoption of such sensors into diagnostic clinics in the future. [ABSTRACT FROM AUTHOR]

An increase in the number of small electronics is anticipated, requiring the preparation of an adequate powering method. A triboelectric nanogenerator, capable of scavenging ambient mechanical energy, is proposed as an efficient means to reduce power consumption for self-sustainable sensors, although its electrical output needs enhancement to broaden its technological applicability. In this work, a magnetic composite comprising iron oxide and polyaniline was synthesized to augment triboelectricity through the modulation of magnetic field intensity using physical chemistry. The crystallinity of the composite, chemical bonding, and structure of the surface are analyzed. The surface potential of the composite, embedded into polydimethylsiloxane, is quantitatively evaluated by using Kelvin probe force microscopy. By amalgamating magnetic flux density and triboelectric outputs, the optimization of the triboelectric layer is achieved, yielding output values of 93.86 V, 6.9 µA, and 127.5 µW. Following a reduction in surface adhesion after the powder coating process, a wind-based triboelectric nanogenerator is fabricated. Its excellent sensitivity to wind and exceptional long-term endurance are assessed, confirming its suitability as a sensor. The practicality of employing this device in intrusion detection, leveraging a wireless door-opening sensor, is demonstrated using synthesized composite materials. [ABSTRACT FROM AUTHOR]

Biocatalytic performance of immobilized ficin onto silica-coated iron oxide magnetic nanoparticles (MNPs) was examined. FTIR study indicated the successful immobilization of ficin onto silica-coated MNPs. The MNPs were synthesized by an ultrasonic-assisted sol-gel method, resulting in coarse silica-coated MNPs with an amorphous or nanocrystalline phase. Results showed that the affinity of ficin to the substrate decreased due to the immobilization. However, the immobilized ficin exhibited enhanced stability and catalytic activity, with a wider pH range and higher thermal stability compared to free ficin. The optimum pH for immobilized ficin activity was found to be shifted from 7.0 to 6.0, making it a suitable candidate for slight acidic conditions. After five days of storage, immobilized ficin retained its initial activity, while free ficin showed a 30% decrease in activity. The immobilized ficin also exhibited a substantially higher activity than its free form after multiple cycles of usage. These findings suggest that immobilized ficin onto silica-coated iron oxide MNPs is a promising candidate for biocatalysis and industrial processes in a wide range of temperature and solutions with high reusability and stability. Highlights: Iron oxide magnetic nanoparticles were successfully coated with silica. The immobilized ficin exhibited enhanced stability and catalytic activity. Immobilized ficin was found to be a suitable candidate for slight acidic conditions. The immobilized ficin exhibited higher activity than its free form after multiple cycles of usage. Immobilized ficin onto silica-coated iron oxide MNPs is a promising candidate for biocatalysis and industrial processes. [ABSTRACT FROM AUTHOR]

In this study, lanthanum (La)-based magnetic biopolymers were synthesized, and the first adsorption study was conducted on the removal of brilliant green dye from aqueous water with these biopolymers. For the adsorption study, adsorption parameters were investigated and the ideal adsorption conditions determined for the removal of brilliant green dye from aqueous solutions are pH 11, t 60 min, m 10 mg, C0 25 mg/L, T 298 K. It was determined that the adsorption process was compatible with the single-layer Langmuir isotherm, and maximum adsorption capacity obtained according to the Langmuir isotherm was calculated as 256.41 mg/g. The adsorption process was found to be in accordance with the pseudo-second-order, and the adsorption process was explained by intra-particle diffusion. According to studies of adsorption thermodynamics, it has been established that the nature of the adsorption reaction is spontaneous, and this process is endothermic and has increasing randomness. Moreover, the reusability of magnetic lanthanum/alginate (La/Alg) biopolymers was investigated, and it was determined that the biopolymers could be used successfully. In summary, brilliant green dye has been successfully removed with simple, low-cost, environmentally friendly, and easily obtained magnetic La/Alg biopolymers. It can be stated that even low amounts of these biopolymers can be effective in the treatment of highly concentrated dye wastewaters. [ABSTRACT FROM AUTHOR]

In biogeochemical phosphorus cycling, iron oxide minerals are acknowledged as strong adsorbents of inorganic and organic phosphorus. Dephosphorylation of organic phosphorus is attributed only to biological processes, but iron oxides could also catalyze this reaction. Evidence of this abiotic catalysis has relied on monitoring products in solution, thereby ignoring iron oxides as both catalysts and adsorbents. Here we apply high-resolution mass spectrometry and X-ray absorption spectroscopy to characterize dissolved and particulate phosphorus species, respectively. In soil and sediment samples reacted with ribonucleotides, we uncover the abiotic production of particulate inorganic phosphate associated specifically with iron oxides. Reactions of various organic phosphorus compounds with the different minerals identified in the environmental samples reveal up to ten-fold greater catalytic reactivities with iron oxides than with silicate and aluminosilicate minerals. Importantly, accounting for inorganic phosphate both in solution and mineral-bound, the dephosphorylarion rates of iron oxides were within reported enzymatic rates in soils. Our findings thus imply a missing abiotic axiom for organic phosphorus mineralization in phosphorus cycling. Iron oxides serve as both adsorbents and catalysts to generate inorganic phosphorus from organic phosphorus in environmental matrices. This abiotic dephosphorylation, which is comparable to enzymatic rates, is a missing piece in phosphorus cycling. [ABSTRACT FROM AUTHOR]

Grazing incidence small angle X-ray scattering (GISAXS) was used to study the structure and interparticle spacing of monolayers of organic ligand-stabilized iron oxide nanocrystals floating at the air–water interface on a Langmuir trough, and after transfer to a solid support via the Langmuir–Blodgett technique. GISAXS measurements of the nanocrystal arrangement at the air–water interface showed that lateral compression decreased the interparticle spacing of continuous films. GISAXS also revealed that Langmuir–Blodgett transfer of the nanocrystal layers to a silicon substrate led to a stretching of the film, with a significant increase in interparticle spacing. [ABSTRACT FROM AUTHOR]

The corrosion behavior and mechanism of 316 stainless steel (316SS) immersed in liquid Pb were investigated in Ar at 650 and 750 °C, respectively. The oxidation corrosion first dominated at 650 °C. The outer layer of the corroded 316SS surface was the loose iron oxide layer, and the inner layer was dense Fe-Cr spinel. However, the selective dissolution of Ni and Cr was dominant at first at 750 °C, and the O diffused to the interface increased with time, then an inner oxide layer is formed with Ni, Cr, and Fe in inner layer of the matrix. The sizes of pores formed by the dissolution gradually increased with the corrosion time increase, and the dissolved area was also partially transformed into the whole. The selective dissolution corrosion of the corroded 316SS was dominant at 750 °C with the time increase. The interaction mechanism between the liquid lead and 316SS was revealed. [ABSTRACT FROM AUTHOR]

Hematite (α -Fe2O3) is widely used in sensor sensitization due to its excellent optical properties. In this study, we present a sensitivity-enhanced surface plasmon resonance alcohol sensor based on Fe2O3/Au. We describe the fabrication process of the sensor and characterize its structure. We conduct performance testing on sensors coated multiple times and use solutions with the same gradient of refractive indices as the sensing medium. Within the refractive index range of 1.3335–1.3635, the sensor that was coated twice achieved the highest sensitivity, reaching 2933.2 nm/RIU. This represents a 30.26% enhancement in sensitivity compared to a sensor with a pure gold monolayer film structure. Additionally, we demonstrated the application of this sensor in alcohol concentration detection by testing the alcohol content of common beverages, showing excellent agreement with theoretical values and highlighting the sensor's potential in food testing. [ABSTRACT FROM AUTHOR]

Internal pipe corrosion within water distribution systems leads to iron oxide deposits on pipe walls, potentially contaminating the water supply. Consuming iron oxide-contaminated water can cause significant health issues such as gastrointestinal infections, dermatological problems, and lymph node complications. Therefore, non-destructive and continuous monitoring of pipe corrosion is imperative for water sustainability initiatives. This study introduces a dual-mode methodology utilizing advanced ultrasound technology and convolutional neural networks (CNN) to quantify pipe corrosion. Scanning acoustic microscopy (SAM) employs high-frequency ultrasound to generate high-resolution images of pipe thickness, indicating iron oxide accumulation. SAM also captures internal pipe data to measure iron oxide concentration in the water. This data, analyzed by CNN, achieves an impressive 95% accuracy. This dual-mode system effectively assesses both the extent of pipe corrosion and water contamination, exemplifying the successful integration of SAM and CNN for precise and reliable monitoring. [ABSTRACT FROM AUTHOR]

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Rheumatoid Arthritis (RA) is regarded as a long-term autoimmune disorder, which triggers inflammation in joints and distresses the organs in the body. Nanotechnology, a science-based technique is a tremendously growing-field with numerous applications where nanoparticles are used to resolve the complications in the habitual life. While comparing to other metals, iron oxide nanoparticles (Fe2O3 NPs) were synthesized at minimal cost using eco-friendly natured materials and also has ability to deliver drug at a specific targeted site. In the present study, a topical nanoemulgel was formulated using Fe2O3 NPs synthesized from Punica granatum. The results of Fe2O3 NPs characterization divulged that the particles were sphere-shaped in nature and the bioactive compounds from the extract acted as capping and reducing agents. Nanoemulgels (F1 to F5) were formulated using different concentrations of Fe2O3 NPs and characterized. Among the formulations F4 nanoemulgel revealed good stability with a zeta potential charge of −53 mV and a polydispersity index of 0.24. L929 cells were treated with F4 formulation and this confirmed that the formulation was non-toxic to normal cells. F4 treated MG63 cell lines revealed the anti-inflammatory property (IC50 = 90.77 μg/ml) of the nanoemulgel. Thus, nanoemulgel containing Fe2O3 NPs synthesized from P. granatum can be an effective, eco-friendly and cost-effective approach to treat RA. [ABSTRACT FROM AUTHOR]

This study investigates enhancing the high-temperature oxidation resistance of hot-stamped steels by adding the Cr/Mn/Si elements to form an extremely thin oxide layer. Under low oxygen partial pressure conditions and high Cr content in the matrix, the oxide layer of a 38Cr3MnNbVMo hot-rolled plate containing the Mo element and high Si content was further thinned to 0.6 μm after cooling at 900 °C for 5 min. The structure of the ultra-thin oxide layer consists of Fe3O4, Mn oxides, FeCr2O4, Cr2O3, and Fe2SiO4 oxides. Compared to other antioxidant elements, under low oxygen partial pressure conditions, Si is more prone to oxidation, forming ultra-thin (22 nm) Fe2SiO4 oxides at the matrix interface. Combined with Cr2O3, FeCr2O4, and Mn oxides, it collectively inhibits the mutual diffusion of external O ions and matrix Fe ions. Furthermore, the addition of the Mo element improves the oxidation resistance. The synergistic effect of multiple powerful oxidation-resistant elements and oxide products effectively inhibits the growth of the iron oxide scale, enhancing the oxidation resistance of hot-rolled, hot-stamped steel. [ABSTRACT FROM AUTHOR]