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Abstract High‑efficiency electromagnetic interference (EMI) shielding materials are of great importance for electronic equipment reliability, information security and human health. In this work, bidirectional aligned Ti3C2Tx@Fe3O4/CNF aerogels (BTFCA) were firstly assembled by bidirectional freezing and freeze-drying technique, and the BTFCA/epoxy nanocomposites with long-range aligned lamellar structures were then prepared by vacuum-assisted impregnation of epoxy resins. Benefitting from the successful construction of bidirectional aligned three-dimensional conductive networks and electromagnetic synergistic effect, when the mass fraction of Ti3C2Tx and Fe3O4 are 2.96 and 1.48 wt%, BTFCA/epoxy nanocomposites show outstanding EMI shielding effectiveness of 79 dB, about 10 times of that of blended Ti3C2Tx@Fe3O4/epoxy (8 dB) nanocomposites with the same loadings of Ti3C2Tx and Fe3O4. Meantime, the corresponding BTFCA/epoxy nanocomposites also present excellent thermal stability (T heat-resistance index of 198.7 °C) and mechanical properties (storage modulus of 9902.1 MPa, Young's modulus of 4.51 GPa and hardness of 0.34 GPa). Our fabricated BTFCA/epoxy nanocomposites would greatly expand the applications of MXene and epoxy resins in the fields of information security, aerospace and weapon manufacturing, etc.

Abstract Background To address the obstacles that come with orthopedic surgery for biological graft tissues, including immune rejections, bacterial infections, and weak osseointegration, bioactive nanocomposites have been used as an alternative for bone grafting since they can mimic the biological and mechanical properties of the native bone. Among them, PCL-PEG-PCL (PCEC) copolymer has gained much attention for bone tissue engineering as a result of its biocompatibility and ability for osteogenesis. Methods Here, we designed a growth factor-free nanoengineered scaffold based on the incorporation of Fe3O4 and hydroxyapatite (HA) nanoparticles into the PCL-PEG-PCL/Gelatin (PCEC/Gel) nanocomposite. We characterized different formulations of nanocomposite scaffolds in terms of physicochemical properties. Also, the mechanical property and specific surface area of the prepared scaffolds, as well as their feasibility for human dental pulp stem cells (hDPSCs) adhesion were assessed. Results The results of in vitro cell culture study revealed that the PCEC/Gel Fe3O4&HA scaffold could promote osteogenesis in comparison with the bare scaffold, which confirmed the positive effect of the Fe3O4 and HA nanoparticles in the osteogenic differentiation of hDPSCs. Conclusion The incorporation of Fe3O4 and HA with PCEC/gelatin could enhance osteogenic differentiation of hDPSCs for possible substitution of bone grafting tissue. Graphical Abstract

Different iron oxide nanoparticles (Fe3O4 and Fe2O3) were prepared by the sol-gel method (titration). The prepared nanoparticles were heated at 90 and 400°C. The morphology surface and structures were characterized by Fourier Transform Infra-Red (FT-IR) and Ultraviolet/Visible (Uv/Visible) measurements, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Atomic Force Microscope (AFM). The enzyme mimetic activities of these nanoparticles (Fe3O4 and Fe2O3) such as two enzymes (Catalase (CAT), and Peroxidase (Pxase)) were measured. The results showed the iron oxides (Fe2O3) heated at 90°C, have the maximum activity (189.99 K.min-1) as catalase (CAT). While the iron oxides (Fe3O4) heated at 90°C, have the maximum activity (3.044 U.min-1) as peroxidase (Pxase), and there is a decrease in the activity for both nanoparticles when annealed at 400°C. Despite the average grain size decrease in both samples, however, the mimetic activity decrease that is mean the average grain size is not affected in both mimetic activities as catalase and peroxidase.

A novel liquid nitrogen quenching treatment is creatively proposed to induced lattice tensile strain of nitrogen/fluorine co-doping Fe 3 O 4 nanocubes assembled on the discarded chrysanthemum tea derived porous carbon as the potential electrocatalyst for optimizing hydrogen evolution. [Display omitted] In this work, the lattice tensile strain of nitrogen/fluorine co-doping ferroferric oxide (Fe 3 O 4) nanocubes assembled on chrysanthemum tea-derived porous carbon is induced through a novel liquid nitrogen quenching treatment (named as TS-NF-FO/PC X -Y, TS: Tensile strain, NF: Nitrogen/Fluorine co-doping, FO: Fe 3 O 4 , PC: Porous carbon, X: The weight ratio of KOH/carbon, Y: The adding amount of porous carbon). Besides, the electrocatalytic activity influenced by the adding amount of porous carbon, the type of dopant, and the introduction of lattice tensile strain is systematically studied and explored. The interconnected porous carbon could improve electrical conductivity and prevent Fe 3 O 4 nanocubes from aggregating. The induced nitrogen/fluorine could cause extrinsic defects and tailor the intrinsic electron state of the host materials. Lattice tensile strain could tailor the surface electronic structure of Fe 3 O 4 via changing the dispersion of surface atoms and their bond lengths. Impressively, the designed TS-NF-FO/PC 5 -0.25 delivers a low overpotential of 207.3 ± 0.4 mV at 10 mA/cm2 and demonstrates desirable reaction dynamics. Density functional theory calculations illustrate that the electron structure and hydrogen adsorption free energy (ΔG *H) are optimized by the synergistic effect among porous carbon, nitrogen/fluorine co-doping and lattice tensile strain, thus promoting hydrogen evolution reaction (HER) catalytic activity. Overall, this work paves the way to unravel the enhancement mechanism of HER on transition metal oxide-based materials by electronic structure and phase composition modulation strategy. [ABSTRACT FROM AUTHOR]

In recent years, there has been a growing concern about heavy metal contamination in sediments. In this study, iron-based granular biochar (MGB) is prepared to remediate Cu and Pb contaminated sediments. Characterizations via scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) show that the rough surface of MGB with abundant pore structures and a large number of oxygen-containing functional groups that facilitate stabilization of Cu and Pb in sediments. Potential mobility and bioavailability of Cu and Pb are investigated using BCR sequential extraction in the 35 day remediation experiment. The XPS results indicate that FeOOH and C-OH play a crucial part in stabilizing heavy metals. Large affinity of FeOOH for Pb allows it to occupy a proportion in F2 while C–OH is attractive to Cu. Changes of pH, organic matter (OM), and available phosphorus (AP) in sediments after adding MGB as well as the relationship between changes and the stable solidification of Cu and Pb are explored. The stable solidification of heavy metals effectively reduces the available phosphorus in sediments. Magnetic and particle properties of the material are used to reduce the impact of MGB aging on sediment environment and separate it from the remediated sediment. Finally, 3% of MGB significantly enhanced the sediment catalase activity in the biological enzyme activity experiment. All findings indicate that MGB is a green and environmentally friendly sediment remediation material with satisfactory potential in synergistically stabilizing heavy metals and phosphorus. Highlights The complexation of FeOOH with Pb on the surface of MGB fixes it to the reduced state The C-OH on the surface of MGB is more attractive to Cu than Pb MGB effectively mitigates the release of bioavailable phosphorus from sediments to overlying water [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The magnetic polymelamine formaldehyde sulfonate was synthesized and evaluated as adsorbent to remove the dyes including methylene blue, malachite green and basic magenta from aqueous media. The structure of the polymer was studied by FTIR, XRD, EDX, SEM, TEM and VSM techniques. Different adsorption parameters including pH, contact time and amount of adsorbent were investigated. The pH optimum values were 5, 4 and 5 for methylene blue, malachite green and basic magenta, respectively. The contact times of 3 min, 30 min and 20 min were the optimum removal time for methylene blue, malachite green and basic magenta, respectively. The optimal amount of adsorbent was 20 mg for all the dyes. The isotherm models showed that the adsorbed isotherms were Freundlich model for green malachite and the Langmuir model for methylene blue and basic magenta dyes. It shows that the adsorption can be homogeneous (monolayer) or heterogeneous (multilayer) for the dyes. Also, the kinetic model of adsorption was closer to the pseudo second-order for all the dyes. It indicates that the rate of adsorption/desorption process (as a chemisorption) controls the overall sorption kinetics. The adsorption efficiencies of ≥ 75% were obtained for the river and tap waters as real samples. [ABSTRACT FROM AUTHOR]

NaOH modified magnetic bagasse biochar (MBC) was successfully prepared and used to adsorb cadmium (Cd (II)) from water. The material was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results showed that MBC had clear layered structures and abundant functional groups, which provided sufficient Cd (II) adsorption sites. The effects, such as pH, MBC doses and initial Cd (II) concentration on the Cd (II) removal were also studied. The results showed that maximum adsorption capacity of Cd (II) by MBC reached 61 mgμg-1 under the optimal conditions. In addition, the adsorption kinetic accorded with the pseudo-second-order models and the adsorption process belonged to chemical adsorption. The adsorption isotherm was more consistent with Freundlich adsorption isotherm model. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shigella, a typical and fatal foodborne pathogen with strong infectivity and survivability in foodstuff, demands a simple and sensitive detecting method. In this study, we reported a novel nanoplatform based on biofunctionalized magnetic nanoparticles (MNPs) modified upconversion nanoparticles (UCNPs) for rapid and specific determination of Shigella. Due to base pairing, Shigella aptamer-functionalized horseradish peroxidase (HRP) combined with complementary strand-modified MNPs@UCNPs. In the absence of Shigella, HRP associated with MNPs@UCNPs were magnetically separated, and colorless 3,3′,5,5′-tetramethylbenzidine (TMB) was oxidized into blue oxTMB. The overlap between oxTMB's absorption peak and MNPs@UCNPs' emission peak caused the fluorescence quenching at 545 nm. The MNPs@UCNPs fluorescence biosensor was achieved to detect Shigella in 1 h, with a limit of detection of 32 CFU/mL. This work showed a rapid and specific sensing platform and produced satisfactory chicken sample results. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Novel nanoparticle drug therapy could be an effective method to enhance peripheral nerve regeneration. Objectives: The current study aimed to determine the effect of Fe3O4 nanoparticles (NP) coated with omega-3 on sciatic nerve regeneration in Wistar rats. Methods: The rats' left sciatic nerve was crushed with a non-serrated clamp. Animals in experimental groups were given Fe3O4@ω3NPs (10 or 30 mg/kg/d) for one week. The recovery of functions was then assessed over eight weeks using a walking track analysis and a hot plate test. In addition, histomorphometry was used to assess the histomorphometric factors. Results: Results showed that Fe3O4@ω3 NPs may have enhanced sciatic nerve regeneration and improved sensorimotor rehabilitation in comparison to the negative controls. These therapeutic effects were significantly greater in Fe3O4@ω3 NPs at a dose of 30 mg/kg. Furthermore, Fe3O4@ω3 NPs treatment, compared to negative controls, significantly reduced gastrocnemius muscle atrophy and improved histomorphometric parameters. Conclusions: It was determined that Fe3O4@ω3 NPs had great potential for nerve regeneration due to the ease of their manufacturing and their desired efficacy. [ABSTRACT FROM AUTHOR]

This work reports the phenoxy carbonylation reactions for the synthesis of aryl esters using magnetically separable nickel supported on Fe3O4. The two main advantages of this process are the use of an inexpensive nickel catalyst and the application of o‐chlorophenyl formate as a both CO source and phenol as a coupling partner. This catalyst is entirely magnetically separable due to the super paramagnetic nature of Fe3O4 and decent reusability potential for up to eight cycles with minimal drops in yields. This protocol tolerates various functionalities of aryl iodides and provided moderate to good yields of corresponding esters. The as‐prepared Ni/Fe3O4 nanoparticles have been characterized using analytical techniques such as FESEM, EDS, TEM, XRD, ICP‐OES, and XPS. [ABSTRACT FROM AUTHOR]

In this paper, our objective was to investigate the static and dynamic magnetic properties of Fe3O4 nanotubes that are 1000 nm long, by varying the external radius and the thickness of the tube wall. We performed a detailed numerical analysis by simulating hysteresis curves with an external magnetic field applied parallel to the axis of the tubes (along the z-axis). Our findings indicate that nanotubes with an external radius of 30 nm exhibit non-monotonic behavior in their coercivity due to a change in the magnetization reversal mechanism, which was not observed in nanotubes with external radii of 80 nm. Additionally, we explored the dynamic susceptibility of these nanotubes and found that the position and number of resonance peaks can be controlled by manipulating the nanotube geometry. Overall, our study provides valuable insights into the behavior of Fe3O4 nanotubes, which can aid in the design and improvement in pseudo-one-dimensional technological devices. [ABSTRACT FROM AUTHOR]

Peltier cooling systems are usually smaller, more portable, and relatively simpler to operate compared to conventional vapor compression cooling systems. For this reason, Peltier cooling systems are widely recommended for use in the field of cooling applications and refrigerators. These cooling systems have relatively low efficiency despite extensive operation. To solve this problem, a Peltier cooling system operated with advanced nanofluid is proposed in this study. In this cooling system, water-based Fe3O4 nanofluids were used to cool the Peltier. In order to obtain high stability in these nanofluids, the nanoparticles were synthesized chemically with surface modification processes (Fe3O4@SiO2@(CH2)3IM). By designing and manufacturing an air-to-nanofluid cooling system, the performance of Peltier cooling system was evaluated and compared to the conventional air-to-water system. The nanofluids were prepared in three different volume concentrations as 0.2%, 0.5% and 1.0% and then were examined at different working conditions. This research has been analyzed using both experimental and numerical methods. Temperature measurements and experimental COP evaluations were made in the cooling chamber. The flow structure and temperature distribution in spiral heat exchanger were closely surveyed and discussed in detail. According to the results obtained, nanofluid volumetric concentrations, inlet temperatures and mass flow rates had a significant effect on the cooling performance of the Peltier systems. It was observed that COP values decreased over time in all experiments and approach zero gradually. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The catalytic pyrolysis of bio-mass can contribute in environmental protection and energy development for the present society. Fe3O4 nanoparticles as a catalyst is synthesized from Fe(NO3)⋅9H2O and FeF3⋅3H2O with different precipitating agents (NaOH, KOH, NH4OH, and RbOH) in the presence of oleic acid as stabilizer. The SEM and XRD data show that iron oxide nanoparticles obtain with NH4OH display smaller spherical particles with large surface area and high crystalinity correspondingly which is further used for catalytic thermal decomposition of peanut shell to obtain bio-oil. The catalyst is applied under different conditions to determine their optimum concentration, reaction temperature, and reaction time. The data show that optimum amount of catalyst is 10% for thermal decomposition of peanut shells; and the optimum temperature for this reaction is 400oC with optimized reaction time of 30 min to give maximum amount of oil. In addition, the as-obtain oil is also applied for antibacterial application, which show outstanding better response against microbes as compare to DMSO. The oil obtained has potential of antibacterial activity which may lead to the formulation of new antibacterial drugs to treat various bacterial infections and this outcome may find applications in waste management to reduce environmental pollution. [ABSTRACT FROM AUTHOR]

A cost-effective alternative for lowering carbon emissions from building heating is the use of flat-plate solar collectors (FPSCs). However, low thermal efficiency is a significant barrier to their effective implementation. Favorable nanofluids' thermophysical properties have the potential to increase FPSCs' effectiveness. Accordingly, this study evaluates the performance of an FPSC operating with Fe3O4-water nanofluid in terms of its thermo-hydraulic characteristics with operating parameters ranging from 303 to 333 K for the collector inlet temperature, 0.0167 to 0.05 kg/s for the mass flow rate, and 0.1 to 2% for nanoparticles' volume fraction, respectively. The numerical findings demonstrated that under identical operating conditions, increasing the volume fraction up to 2% resulted in an improvement of 4.28% and 8.90% in energy and energy efficiency, respectively. However, a 13.51% and 7.93% rise in the friction factor and pressure drop, respectively, have also been observed. As a result, the performance index (PI) criteria were used to determine the optimal volume fraction (0.5%) of Fe3O4 nanoparticles, which enhanced the convective heat transfer, exergy efficiency, and energy efficiency by 12.90%, 4.33%, and 2.64%, respectively. [ABSTRACT FROM AUTHOR]

A simple method was reported to achieve a green yolk–shell Fe3O4@SiO2@CuO nanocatalysts (YS‐Fe3O4@SiO2@CuO). Glucose (G) and lactose (L), as a grafting agent, were applied for decorating CuO on the magnetic nanoparticles surface and then using calcination method, yolk–shell structure was obtained. Characterization of nanocatalysts was carried out using inductively coupled plasma–optical emission spectrometry (ICP‐OES), field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), energy‐dispersive X‐ray (EDX)‐Mapping, thermogravimetric analysis (TGA), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), Brunauer, Emmett, and Teller (BET), and vibrating sample magnetometer (VSM) analyses and the results confirmed the successful synthesis of these catalysis. The activity of the nanocatalysts were studied to reduce nitroaromatic compounds monitoring by UV–Vis spectra. In the model reaction, 4‐nitrophenol was reduced using YS‐Fe3O4@SiO2@CuO(G) and YS‐Fe3O4@SiO2@CuO(L), with the activity factors (k′) of 3218 and 2023 s−1 g−1, and rate constants (Kapp) of 0.56 and 1.19 min−1, respectively. The advantages of prepared nanocatalysts were good stability and high conversion. The magnetic property of nanocatalysts makes them easy to recover in multiple cycles. [ABSTRACT FROM AUTHOR]

Silicon/carbon composites have been considered as the anode material of choice for improving the energy density of lithium-ion batteries (LIBs). The carbon-based matrices not only can provide a conductive network for Si, but can also mitigate the bulk expansion of Si. However, the Si/C anode also has obvious disadvantages, such as a complicated preparation process and unstable solid–electrolyte interface (SEI) film, which leads to low initial coulombic efficiency and poor cycle life. In this study, ferrocene was successfully used as the sole source of Fe3O4 and carbon to prepare a core–shell structured Si@Fe3O4@C composite by wrapping a Fe3O4@C layer on the Si surface under hydrothermal action. The synthesized Si@Fe3O4@C composite exhibits excellent cycling stability (1026 mA h g−1 after 500 cycles at 1 A g−1) and rate performance (744 mA h g−1 at 4 A g−1). The good electrochemical performance can be ascribed to Fe3O4 nanoparticles embedded into the carbon layer, which effectively improves the electronic conductivity and interfacial stability of Si@C anode materials. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of photocatalytic materials and realize the greening of materials, in this study, the magnetic photocatalytic materials were prepared by doping Ni-NiO/Fe3O4-GR with lignocellulose as the initial material and TiO2 as the catalytic bulk material. The results showed that the photocatalytic efficiency of methylene blue was significantly different with different proportions of Fe3O4-GR (G1F1). When the addition of photocatalytic material complex G1F1 was at 8.3% of the mass of lignocellulose, the photocatalytic efficiency could reach 91.92%, indicating excellent photocatalytic performance. [ABSTRACT FROM AUTHOR]

Graphene has emerged as an exceptional material for industrial usage and has widely been implemented. In this regard, the current study examines the enhanced characteristics of graphene nanoplatelets (GNP) by depositing the magnetite iron oxide (Fe3O4) on its surface. Ethylene glycol solvent was taken in Fe3O4 and GNP samples formation which were synthesized by the time parameter at various intervals. The Physicochemical characterizations were carried out by FTIR, XPS, XRD, and FESEM. It was observed that the successful grafting of iron particles on the GNP surface was achieved at a high time interval, and the results were more significant. FESEM images reveal a spherical structure on the surface of the graphene nanoplatelets in the GG 1, GG 2, and GG 4 sample. Fe3O4 has an irregular morphology with pores observed on the surface of GNP. However, the surface morphology of the graphene changes to a crinkled and rough surface.

The magnetic Fe3O4-HKUST-1 nanocomposites were synthesized using a simple and green hydrothermal technique, utilizing Fe3O4 and the chemically stable metal–organic framework HKUST-1. The Fe3O4-HKUST-1 nanocomposites were synthesized with a varied proportion of Fe3O4 and subjected to advanced characterization, which included XRD, IR, BET, TG, SEM, TEM, EDS, and VSM. The magnetic nanocomposite 0.4 Fe3O4-HKUST-1 (FH4) had a rough surface with spherical morphology and a good proportion of micro and mesopores. The magnetic nanocomposite had a mean pore size of 2.58 nm, with pore volume of 0.35 cm3/g, having excellent magnetic saturation performance (26.39 emu/g). The adsorption isotherm and adsorption kinetics of magnetic nanocomposites on azo dye neutral red (NR) wastewater were assessed in detail. In contrast to the Freundlich model, the Langmuir model better described the adsorption isotherms, while the pseudo-second-order kinetic model better captured the adsorption kinetics. The FH4 magnetic nanocomposite was the most effective adsorbent with the highest adsorption capacity for NR separation.

The availability of rapid and low-cost instruments to detect magnetic nanoparticles (MNPs) concentrations is vital in giant magnetoresistance (GMR)-based biosensors. This paper reports a new setup for a simple GMR sensor using the commercial chip AAL024 as a transducer. It was combined with a basic differential amplifier and microcontroller to acquire digital output voltages for the detection of green-synthesized (GS)-Fe3O4 MNPs as a label and streptavidin-coated MNPs in biosensor applications. As a characteristic feature of Fe3O4, the GS-Fe3O4 MNPs displayed a cubic inverse spinel structure. The average GS-Fe3O4 particle size was 11 nm and they exhibited soft ferromagnetic behavior with a saturation magnetization (MS) of 55.5 emu/g. Owing to the presence of phytochemical components in the Moringa oleifera (MO) extract, the MS of GS-Fe3O4 was lower than that of Fe3O4. To study sensor performance, the detection of the GS-Fe3O4 MNP labels and streptavidin-coated MNPs assay was investigated. Using the microcontroller as the supply voltage for the AAL024 and an analog-to-digital converter simplified data collection and made any additional measuring instruments unnecessary. The sensor showed promising performance with the GS-Fe3O4 MNP label and streptavidin assay owing to the linear correspondence between the signal and concentration of the MNP label. A small limit-of-detection of 4 mg/mL was achieved for GS-Fe3O4. The sensitivity of GS-Fe3O4 and streptavidin were 2.79 and 1.80 mV/(mg/mL), respectively. Moreover, the excellent stability and reproducibility of the sensor were confirmed by the stable signal for over 30 s with relative signal deviation (RSD) ranges of 2–20% and 2–10% for MNPs and streptavidin, respectively.

The escalating contamination of water bodies with antibiotic residues is an urgent environmental and public health issue. This study aimed to fabricate an innovative photocatalytic composite (CMZ) by combining chitosan, magnetic iron oxide (Fe _3 O _4 ), and zinc oxide (ZnO) for efficiently removing antibiotic moxifloxacin (MFX) water. Comprehensive characterization of the fabricated CMZ was performed using various techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), photoluminescence spectroscopy (PL) and nitrogen adsorption/desorption isotherm analysis. The synergistic incorporation of ZnO, Fe _3 O _4 , and chitosan in the CMZ composite altered the structural properties of ZnO and chitosan The band gap energy of CMZ was 2.58 eV, significantly boosting its photocatalytic effectiveness under visible light exposure. The CMZ composites exhibited a high efficiency in catalyzing MFX degradation in aqueous environments. The optimal conditions for MFX degradation were established, including a neutral pH level of 7, a 90 min exposure to irradiation, and employing 0.1 g of the CMZ catalyst. The degradation process obeyed closely to the first-order kinetic model. The CMZ material showed consistently high performance in degrading MFX across four consecutive reuse cycles, emphasizing its practical applicability for mitigating antibiotic pollution.

In order to solve the problems of low cathode conductivity, shuttle effect, and poor electrochemical performance of Li-S batteries, we designed a porous carbon/nano-sized ferric oxide (Fe _3 O _4 ) composite modified membrane. This improved both conductivity and adsorption capacity of lithium polysulfides (LiPSs) prepared with mesopores and high specific surface area C-Fe _3 O _4 @PE. The membrane can bind polysulfide via chemical and physical adsorption. Owing to these advantages, a Li-S battery based on C-Fe _3 O _4 @PE and with a separator exhibited excellent rate performance (965.9 mA h g ^–1 at 0.2 C and 437.5 mA h g ^–1 at 5 C), as well as a long cycle life (416.6 mA h g ^–1 after 300 cycles at 0.5 C, with a capacity retention rate of 50.5%).

Ti3C2Tx MXene is one of the most comprehensively studied 2D materials in terms of its adsorptive, transport, and catalytic properties, cytotoxic performance, etc. Still, conventional MXene synthesis approaches provide low single-flake MXene yield and frequently uncontrollable properties, demanding further post-processing. The MXene family also lacks magnetism, which is helpful for producing effective nanoadsorbents as their magnetic decantation is the cheapest and most convenient way to remove the spent adsorbent from water. Composite materials consisting of magnetic nanoparticles grown on top of MXene flakes are commonly used to provide magnetic properties to the resulting nanocomposite. In this paper, we study the possibility to delaminate multilayer Ti3C2Tx MXene sheets directly by growing iron oxide magnetic nanoparticles inside their interlayer spacing. We find out that, with a mass fraction of particles comparable or exceeding that of MXenes, their growth is accompanied by an effective enhancement of single-layer MXene yield and suitable magnetic properties of the resulting composite. The developed approach can be further used for simplifying synthesis protocols to obtain magnetic MXene-based nanoadsorbents with tunable properties.

To prepare USPIO-PEG-Cy5.5 targeted bimodal probe for noninvasive diagnosis of thyroid cancer. The characterization was verified, and the physical and chemical properties were discussed. Fe3O4 was used as the carrier. Fluorescent Cy5.5 was linked with polyethylene glycol (PEG). A small amount of Cy5.5-NHS fluorescent powder were dissolved in dimethyl sulfoxide solution. PEG-Fe3O4 nanoparticles were centrifuged and ultra-filtrated. The nanoparticles were resuspended with phosphate buffer to change the pH. The Cy5.5 fluorescence was added to the Fe3O4 particles and incubated at 37 °C for 2 h. Characterization test of Cy5.5-PEG-Fe3O4 and relaxation rate measurement were performed. Fro cells were used to perform cell imaging experiment. CCK-8 assay was carried out to detect the cytotoxicity. The bimodal molecular probe Cy5.5-PEG-Fe3O4 was synthesized successfully. Transmission electron microscopy showed that the particle size of the probe was 18.8 ± 3.5 nm, the water and particle size of the nanoparticles was 35.7 ± 18.6 nm, and the zeta potential was −18.0 mv. The relaxation rate was 0.044 and the slope was 0.97. The cytotoxicity test showed that the bimodal molecular probe had slight toxicity to fro cells with a concentration-dependent manner. The synthesized Cy5.5-PEG-Fe3O4 probe has low toxicity, good biocompatibility, stable particle size, which can be used for cell imaging for noninvasive diagnosis of thyroid cancer.

In this study, at first, 2-amino-1,4-dihydropyrimidine was synthesized by the reaction of guanidine hydrochloride, 4-methybenzaldehyde and ethyl benzoylacetate in the presence of sodium hydrogencarbonate as catalyst. Also, Fe3O4 nanoparticles were synthesized and functionalized via sequential reactions with chloropropyl(trimethoxy)silane and 2-aminopyridine. The resulting nanoparticles were used as environmentally benign magnetic nano-catalyst for the synthesis of some novel ethyl 2-amino-4-aryl-8-(4-methylphenyl)-3-cyano-6-phenyl-8,4-dihydro-1H-pyrimido[1,2-a]pyrimidine-7-carboxylate derivatives via a one-pot reaction of 2-amino-1,4-dihydropyrimidine, an aromatic aldehyde, and malononitrile. All the reaction steps are performed under ultrasound irradiation. Simple operation, high reaction yields, reusability of the catalyst for several times, short reaction times and easy separation of catalyst are the key advantages of using this catalyst.

The primary aim of this study is to develop an economical, stable, and effective heterogeneous catalyst for wastewater remediation via the Fenton oxidation process. For this purpose, Fe 3 O 4 -montmorillonite alginate (FeMA) composite beads were synthesized by entrapping Fe 3 O 4 -montmorillonite in calcium alginate beads. The performance of the catalysts was evaluated via the Fenton degradation of ofloxacin (OFL), an antibiotic that is frequently detected in water bodies. The physiochemical properties of the FeMA composite beads were characterized using X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscope/energy dispersive X-ray (FESEM/EDX), Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). FeMA composite beads were found to have a higher surface area, higher porosity, and better thermal stability compared to pristine alginate beads. The composite beads were subsequently used for Fenton degradation of ofloxacin (OFL) in an aqueous solution. The effects of Fe 3 O 4 -montmorillonite loading on alginate, FeMA composite beads dosage, initial solution pH, initial OFL concentration, different oxidants, H 2 O 2 dosage, reaction temperature, and inorganic salts on Fenton degradation of OFL in aqueous solution was investigated. The results revealed that the percentage of OFL degradation reached about 80 % under optimized conditions, while the total organic carbon (TOC) removal reached about 53 %. The entrapment of Fe 3 O 4 -montmorillonite in alginate beads results in less iron ions leaching compared to previous observation, and the efficiency remains constant over the five cycles investigated. The kinetics of the Fenton degradation process are best fitted to the pseudo-first-order kinetic model. It is therefore believed that FeMA composite beads can be a promising material for wastewater remediation via the Fenton oxidation process. [ABSTRACT FROM AUTHOR]

Nanodiamonds with magnetic resonance imaging (MRI) and targeted drug delivery to exert combined effects for biomedical applications have been considered to be an urgent challenge. Herein, a novel bio-nanoarchitectonics (Fe3O4@NDs) with simultaneous imaging and therapeutic capacities was fabricated by covalently conjugating nanodiamonds (NDs) with Fe3O4. Fe3O4@NDs exhibited better biocompatibility and excellent photothermal stability with superb photothermal conversion performance (37.2%). Fe3O4@NDs has high doxorubicin (DOX) loading capacity (193 mg/g) with pH and NIR-responsive release characteristics. Fe3O4@NDs loading DOX showed a combined chemo-photothermal inhibitory effect on the tumor cells. Enhanced T2-weighted MRI contrast toward the tumor, with the assistance of a magnetic field, convinced the Fe3O4@NDs gathered in the tumor more efficiently and could be used for MRI-based cancer diagnosis. Our results revealed an effective strategy to achieve a stimuli-sensitive nanoplatform for multifunctional theranostics by the combined action. [ABSTRACT FROM AUTHOR]

The shortage of water resources has always been one of the most difficult problems that perplexes humanity. Solar steam generation (SSG) has been a new non-polluting and low-cost water purification method in recent years. However, the high cost of traditional photothermal conversion materials and the low efficiency of photothermal conversion has restricted the large-scale application of SSG technology. In this work, composite materials with Fe3O4 nanospheres attached to MoS2 nanosheets were synthesized, which increased the absorbance and specific surface area of the composite materials, reduced the sunlight reflection, and increased the photothermal conversion efficiency. During the experiment, the composite material was evenly coated on cotton. The strong water absorption of cotton ensured that the water could be transported sufficiently to the surface for evaporation. Under one sun irradiation intensity, the evaporation rate of the sample synthesized in this work reached 1.42 kg m−2 h−1; the evaporation efficiency is 89.18%. In addition, the surface temperature of the sample can reach 41.6 °C, which has far exceeded most photothermal conversion materials. Furthermore, the use of this composite material as an SSG device for seawater desalination and sewage purification can remove more than 98% of salt ions in seawater, and the removal rate of heavy metal ions in sewage is close to 100%, with a good seawater desalination capacity and sewage purification capacity. This work provides a new idea for the application of composite materials in the field of seawater desalination and sewage purification. [ABSTRACT FROM AUTHOR]

Herein, Fe3O4 nanoparticles and graphene oxide (GO) are compounded first, followed by the addition of cellulose nanofiber (CNF) and l-ascorbic acid, to obtain Fe3O4@reduced graphene oxide (rGO)/CNF foams via the freeze-drying method. The electrical conductivity and magnetism of as-prepared foams were improved due to the presence of rGO and Fe3O4, which is suitable for electromagnetic interference (EMI) shielding material. The results exhibit that Fe3O4@rGO/CNF foams all possess a porous structure, and the optimized foam shows an EMI shielding effectiveness value of ~ 23 dB in the X-band. The good EMI shielding performance of the Fe3O4@rGO/CNF foam originates from the synergy of its composition and structure. This work could provide a reference for the design and fabrication of novel EMI shielding materials. [ABSTRACT FROM AUTHOR]

A major drawback of nanoparticles (NPs) for biomedical applications is their preferential phagocytosis in immune cells, which can be avoided by surface modifications like PEGylation. Nevertheless, examinations of different polyethylene glycol (PEG) chain lengths on the competence of immune cells as well as possible immunotoxic effects are still sparse. Therefore, primary murine macrophages and dendritic cells were generated and incubated with magnetic nanoporous silica nanoparticles (MNPSNPs) modified with different mPEG chains (2 kDa, 5 kDa, and 10 kDa). Cytotoxicity, cytokine release, and the formation of reactive oxygen species (ROS) were determined. Immune competence of both cell types was examined and uptake of MNPSNPs into macrophages was visualized. Concentrations up to 150 µg/mL MNPSNPs showed no effects on the metabolic activity or immune competence of both cell types. However, ROS significantly increased in macrophages incubated with larger PEG chains, while the concentration of cytokines (TNF-α and IL-6) did not indicate a proinflammatory process. Investigations on the uptake of MNPSNPs revealed no differences in the onset of internalization and the intensity of intracellular fluorescence. The study gives no indication for an immunotoxic effect of PEGylated MNPSNPs. Nevertheless, there is still a need for optimization regarding their internalization to ensure an efficient drug delivery. [ABSTRACT FROM AUTHOR]

In this study, both wood flour (WF) and wood flour-derived biochar (WFB) were used as supports for Fe3O4 to activate peroxydisulfate (PDS). The role of different carriers was investigated emphatically from the aspects of catalyst properties, the degradation kinetics of bisphenol A (BPA), the effects of important parameters, and the generation of reactive oxygen species (ROS). Results showed that both WF and WFB could serve as good support for Fe3O4, which could control the release of iron into solution and increase the specific surface areas (SSAs). The WFB/Fe3O4 had stronger PDS activation capability than WF/Fe3O4 mainly due to the larger SSA of WFB/Fe3O4 and the PDS activation ability of WFB. Both radical species (•OH and SO4•−) and non-radical pathways, including 1O2 and high-valent iron-oxo species, contributed to the degradation of BPA in the WFB/Fe3O4–PDS process. Moreover, the WFB/Fe3O4 catalyst also showed stronger ability to control the iron release, better reusability, and higher BPA mineralization efficiency than WF/Fe3O4. [ABSTRACT FROM AUTHOR]

In this work, an Fe3O4 catalyst was synthetized in a single step via electrochemical synthesis. The Fe3O4 catalyst was used to evaluate the degradation of Ofloxacin (OFX) using a heterogeneous advanced oxidation process with sodium persulfate (PS). PS activation was successfully achieved via thermal conventional heating directly and subsequently applied for the degradation of OFX. The degradation kinetics were studied under different conditions, such as catalyst and oxidant concentration and temperature. The results show that a higher reaction temperature, catalyst and initial PS dose strongly influence the degradation efficiency. Thermal activation of persulfate was tested at 20, 40 and 60 °C. At 60 °C, the half-time of OFX was 23 times greater than at 20 °C, confirming the activation of persulfate. Mineralization studies also showed that under optimized conditions (20 mM of persulfate, 1 g/L catalyst and 100 mg/L OFX), a 66% reduction in organic matter was observed, in contrast to that obtained at 40 °C and 20 °C, which was null. The reusability, as tested through the fourth reuse cycle, resulted in a 38% reduced degradation efficiency when comparing the first and last cycle. Furthermore, the electrosynthesized catalyst presented similar degradation efficiencies in both real water and MilliQ, mainly because of the C l 2 − generation at high C l − concentrations that takes place in C l − contaminated water. [ABSTRACT FROM AUTHOR]

Magnetic coagulants (M-HAFAC), using fly ash modified by hydrochloric acid, sulfuric acid, sodium hydroxide and ferric chloride as raw materials and nano Fe3O4 as magnetic seed, were prepared as an adsorbent for Cr(Ⅵ) in wastewater. Experiments and characterization analysis were performed on the prepared magnetic coagulant. The coagulation experimental results showed that the coagulant prepared on the basis of hydrochloric acid modified-fly ash (HAFAC) had the best adsorption properties, and the removal rate of Cr6+ could reach 97.53%. Zeta potential, BET, SEM, XRD, XPS characterization results showed that the mechanism of Cr(Ⅵ) removal by the modified fly ash-based magnetic coagulant was the synergistic effect of electro-neutralization and chemical precipitation. Kinetic and thermodynamic analyses showed that the adsorption behavior of Cr6+ adsorption by magnetic coagulants is dominated by monolayer adsorption and chemisorption, and the adsorption process heat absorption can proceed spontaneously. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Molecular Science is the property of Journal of Molecular Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Molecular Science is the property of Journal of Molecular Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fe3O4/reduced graphene oxide (RGO) nanocomposite powders were directly synthesized by solution combustion method using ferric nitrate and graphene oxide as oxidants and glycine as fuel at fuel to oxidant ratio of 1. The structural, microstructural, and electrochemical properties were investigated as a function of RGO contents. The Fe3O4 nanoparticles were dispersed on the RGO nanosheets, forming a honeycomb-like microstructure. With the increase of RGO nanosheets, the specific surface areas and pore volume increased from 20.5 to 170 m2/g and from 0.06 to 0.80 cm3/g, respectively, due to the open structure of RGO sheets. The Fe3O4-18 wt% RGO nanocomposite exhibited a high reversible capacity of ~ 700 mAh g−1 at a current density of 1 A g−1 and excellent cycling stability with a capacity retention of 95% following 250 cycles. The superior electrochemical performance of Fe3O4/RGO nanocomposites was attributed to the hierarchical porous structure of RGO nanosheets. The microstructural features benefitted from shortening the diffusion path of Li+ and preventing the aggregation of Fe3O4 nanoparticles. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are gradually used since of their huge specific surface area and superior pore structure. However, there are problems such as easy aggregation and difficult separation in water treatment. In this study, we prepared composite microspheres (FMCS-1) by modifying MIL-125-NH 2 with Fe 3 O 4 and chitosan. The structural characterization and performance analysis of the materials showed that the introduction of chitosan effectively prevents the stacking of MOFs. The magnetic test manifested that Fe 3 O 4 solved the problem of the difficult separation of MOFs from water. The removal potential of toxic Cr(VI) was tested by adsorption experiments. The isotherm model indicated that FMCS-1 is a single molecular layer adsorbent with a maximum adsorption capacity of 109.46 mg/g at pH = 2. The adsorption kinetics showed that the adsorption of Cr(VI) by FMCS-1 was chemical adsorption. The acid resistance test demonstrated that FMCS-1 can exist stably in acid solutions. The recycling experiments proved that the adsorbent can be reused and the removal percentage still reaches 50 % after 5 cycles. This work expands the application of MOFs in water treatment and also provides an effective adsorbent for Cr(VI) removal. [Display omitted] • A magnetic MIL-125-NH 2 @chitosan composite was prepared. • Physicochemical properties of FMCS-1 microspheres were evaluated. • FMCS-1 microspheres displayed high efficiency for Cr(VI) removal. • The adsorption mechanism of Cr(VI) by FMCS-1 was investigated. • FMCS-1 can efficiently separate from aqueous solutions. [ABSTRACT FROM AUTHOR]

This work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and mercury intrusion porosimetry (MIP) tests were performed. The results showed that increasing the amount of Fe3O4 NPs in a mix leads to a gradual increment in measured viscosity and yield stress. High nano-Fe3O4 content substantially impeded the early strength development process and led to a decrement in the 7- and 28-day compressive strength of cement paste. The MIP studies exhibited a gradual increment in total porosity, and average pore volume, as nano-Fe3O4 content was increased. All the macroscopic cross-sections of slow, fast and thermal neutrons constantly increased as a result of the addition of magnetite nanoparticles, with their variations being markedly linear. Similarly, gamma attenuation test results indicated that the addition of Fe3O4 powder enhances the shielding capability of paste in the energy range of interest (0.08–2.614 MeV). In conclusion, Fe3O4 nanoparticles can be successfully used in producing lead-free cementitious composites with improved gamma-ray and neutron shielding properties. However, certain drawbacks related to an increment in matrix porosity and thus a decrement in mechanical performance should be taken into account. [ABSTRACT FROM AUTHOR]