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In this study, forming limit diagrams (FLDs), fracture toughness (FT), mechanical, magnetic, and electro-physical properties of Al/Fe2O3 composites have been investigated experimentally. Accumulative-roll-bonding (ARB) process was used to manufacture composite samples. Then, Al/Fe2O3 composites have been produced at 300∘C up to eight ARB passes. Also, magnetic composites have been fabricated with 0, 5% and 10wt.% of particles. The interlayer bonding quality was improved at higher passes. By studying the SEM rapture morphology, it was shown that the rapture mode changed to shear ductile for samples with more passes. For composite samples fabricated at higher passes and in comparison with the annealed sample, elongated dimples were turned to shallow dimples. FLDs area as the main forming criterion dropped severely after pass one and then began to improve at higher passes. Fracture test results showed that after the 8th pass, the value of FT improved gradually to the maximum value of 34.3MPam1∕2. [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]

With the continuous advancement of carbon peaking and carbon neutrality goals worldwide, the concept of "hydrogen replacing carbon" is gradually becoming the mainstream for the future development of the steel industry. It plays a crucial role in achieving carbon reduction at the source and breaking away from dependence on fossil fuels. Based on this, this study focuses on the kinetic research of non-isothermal reduction of different iron-containing raw materials under a hydrogen atmosphere. The TG curve and DTG curve in the temperature range from room temperature to 1223K were obtained by thermogravimetric analysis. The research reveals that the hydrogen reduction of iron-containing raw materials can be divided into three stages. In the Stage Ⅰ, hydrogen exhibits strong reduction ability towards HM iron concentrate powder and BY iron concentrate powder, with apparent activation energies of 19.997 kJ/mol and 23.863 kJ/mol, respectively. In the Stage Ⅲ, the presence of Wüstite and MgFe 2 O 3 in HM iron concentrate powder and BY iron concentrate powder hinders the reduction rate. Throughout the reaction stages, the hydrogen reduction of HF ore powder and PB ore powder requires overcoming relatively small reaction barriers, with apparent activation energies of 62.274 kJ/mol and 64.568 kJ/mol, respectively. This analysis provides a theoretical basis for the effective hydrogen reduction of iron-containing raw materials. [Display omitted] • Exploring the reduction behavior of iron-containing raw materials during heating using non-isothermal methods. • Classifying reaction regions based on the variations in TG and DTG curve profiles. • It is proposed that in the Stage Ⅲ of the reaction, the formation of MgFe 2 O 4 leads to an increase in activation energy. • In proposing a deceleration in the Stage Ⅲ of the reaction, two factors may be considered. [ABSTRACT FROM AUTHOR]

In porous water filters, the transport and entrapment of contaminants can be modeled as a classic mass transport problem, which employs the conventional convection–dispersion equation to predict the transport of species existing in trace amounts. Using the volume-averaging method (VAM), the upscaling has revealed two possible macroscopic equations for predicting contaminant concentrations in the filters. The first equation is the classical convection–dispersion equation, which incorporates a total dispersion tensor. The second equation involves an additional transport coefficient, identified as the adsorption-induced vector. In this study, the aforementioned equations were solved in 1D for column tests using 3D unit cells. The simulated breakthrough curves (BTCs), using the proposed micro–macro-coupling-based VAM model, are compared with the direct numerical simulation (DNS) results based on BCC-type unit cells arranged one-after-another in a daisy chain manner, as well as with three previously reported experimental works, in which the functionalized zeolite and zero-valent iron fillings were used as an adsorbent to remove phosphorous and arsenic from water, respectively. The disagreement of VAM BTC predictions with DNS and experimental results reveals the need for an alternative closure formulation in VAM. Detailed investigations reveal time constraint violations in all the three cases, suggesting this as the main cause of VAM's failure. [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]

In this study, novel multifunctional magnetic silver nanoparticles complexed with hexadecylamine-functionalized sulfur- and nitrogen-co-doped graphene quantum dots (AgNPs@Fe3O4-C16SNGQDs) were tested for the removal of phenanthrene and as antibacterial agents from an aqueous solution. The resulting materials were successfully applied as adsorbents and antibacterial agents in batch adsorption and disk diffusion tests. An average Brunauer–Emmett–Teller (BET) surface area of 83.7 and 85.3 m2/g was obtained for AgNPs@Fe3O4 and AgNPs@Fe3O4-C16SNGQDs, respectively. Accordingly, adsorption capacity evaluated using the Langmuir adsorption isotherm was found to be 4097.7 and 5965.7 mg/g for AgNPs@Fe3O4 and AgNPs@Fe3O4-C16SNGQDs, respectively, after 24 h mixing time. The modification of AgNPs@Fe3O4 with C16-SNGQDs facilitated higher adsorption performance at ambient temperature, which is more sustainable and cost-effective when considering large-scale use. Furthermore, C16-SNGQDs showed increased antibacterial activity against negatively charged bacterial strains, whereas AgNPs@Fe3O4-C16SNGQDs showed enhanced inhibition against gram-positive bacteria. Hence, multifunctional nanoparticles have the potential for microbial and chemical pollution remediation and could significantly improve current water treatment methods. [ABSTRACT FROM AUTHOR]

Materials based on iron oxide were prepared via a closed system solution combustion synthesis (IOP), evaluating the effect of adding mango seed husk (T), peel (C), and a mixture of the portions (M) on the material properties obtained (IOT, IOC, and IOM, respectively). The structural (XRD, Mössbauer), morphological (SEM and TEM), optical (UV-VIS diffuse reflectance), textural (BET), and magnetic (VSM) properties of the materials obtained were evaluated. Different phase compositions (hematite, magnetite, and maghemite) were identified in the structure of the materials. Adding mango residue favored the formation of magnetite with superparamagnetic particles in the IOC sample. The solids were evaluated in the methylene blue photocatalysis at different concentrations, observing different effects on the discoloration rate. The IOP sample performed better at the lowest concentration (50 mg L−1) of the dye, with 98% discoloration after 90 min and a specific speed of 44.7 × 10−3 min−1, which can be explained by the heterojunction effect, making electronic recombination harder and increasing the quantum yield of the photocatalyst. At 70 mg L−1 concentration, the best catalyst was the IOM with 82% discoloration and a specific speed of 15.8 × 10−3 min−1, explained by the increase in the specific area due to the insertion of biomass, which improved adsorptive capacity, maintaining the observed heterojunction effects. Under sunlight, the best composite was IOC, with 90.5% discoloration and activity of 29.8 × 10−3 min−1, justified by combining favorable textural and optical properties. [ABSTRACT FROM AUTHOR]

Iron silver oxide (AgxFe2−xO3; 0xFe2−xO3 shown in the figure can be indexed to the hexagonal structure of silver oxide and the rhombohedral structure of hematite and new X-ray Diffraction (XRD) peaks of AgxFe2−xO3 structure. The annealing and doping process seems to cause a serious change in the crystal structure of the thin film, it showed a serious change in its electrical properties. The electrical parameters of resistance for thin films were measured using the Hall measurement method at room temperature. With Hall measurements, the n-type carrier concentration of the Fe2O3 structure was calculated, and it was observed that its resistance was 1MΩ. Likewise, it was observed that AgxFe2−xO3 exhibited an n-type carrier concentration, and its resistance was calculated to be 0.5MΩ. The conductivity change is based on silver doping. The doping process seems to cause a change in the bandgap of the thin film, it showed a change in its optical properties. The film’s optical absorption was measured by UV–Vis photo spectroscopy. Subsequently, the structural and topographic properties of AgxFe2−xO3 structures were investigated by high-precision characterization devices. [ABSTRACT FROM AUTHOR]

The absence of adequate methods for hydrogen storage has prevented the implementation of hydrogen as a major source of energy. Graphene-based materials have been considered for use as solid hydrogen storage, because of graphene's high specific surface area. However, these materials alone do not meet the hydrogen storage standard of 6.5 wt.% set by the United States Department of Energy (DOE). They can, however, be easily modified through either decoration or doping to alter their chemical properties and increase their hydrogen storage capacity. This review is a compilation of various published reports on this topic and summarizes results from theoretical and experimental studies that explore the hydrogen storage properties of metal-modified graphene materials. The efficacy of alkali, alkaline earth metal, and transition metal decoration is examined. In addition, metal doping to further increase storage capacity is considered. Methods for hydrogen storage capacity measurements are later explained and the properties of an effective hydrogen storage material are summarized. [ABSTRACT FROM AUTHOR]

The electrocatalytic recycling of waste nitrate (NO3RR) is a promising decentralized route for green ammonia synthesis. Nonetheless, it suffers from the competing hydrogen evolution reaction and the insufficient proton supply in high pH conditions. Herein, iron oxide nanoparticles anchored on ZnO is introduced as a strategy to enhance the water dissociation ability and proton transfer rate, advancing NH4+ production from alkaline NO3RR. Supported by a set of ex situ and in situ characterization, the findings reveal the reduction of iron oxides, along with improvements in charge transfer properties and proton generation from H2O. Theoretical calculations show that iron oxides reduce the kinetic barrier of the rate‐limiting step (*NO2‐to‐*NO2H) and result in a thermodynamically favorable process to hydrogenation steps, which in turn reduce the overall energy barrier of alkaline NO3RR. Optimal catalytic activity is realized with a Fe loading of 0.5 wt.%, delivering a Faradaic efficiency of ≈83% for ammonium with a NH4+ yield rate of 31 nmol s−1 cm−2 at −0.7 V versus RHE. The results pave the way for the utilization of bi‐metal interaction to tune the reaction pathway for achieving sustainable ammonium synthesis in alkaline, contributing to ongoing efforts to achieve a sustainable nitrogen cycle via N‐based electrochemistry. [ABSTRACT FROM AUTHOR]

Copper-promoted iron oxides are commonly utilized in high-temperature water-gas shift (WGS) reactions. Although the promotional effect of Cu has been previously documented, the nature of the active sites for Cu/Fe 3 O 4 remains debated and the role of the crystallite size of Fe 3 O 4 has not been tackled. In this study, a wide range of Cu/Fe 3 O 4 catalysts were designed by hosting Cu species onto Fe 3 O 4 of two contrasting crystallite sizes (approximately 10 and 160 nm) and by utilizing different preparation methods (ammonia evaporation and deposition-precipitation). The evaluation of their catalytic WGS performances revealed a remarkable and previously undocumented phenomenon: the addition of Cu resulted in universal activity enhancements only for small Fe 3 O 4 crystals, while the larger analogues displayed decreased activity. This peculiar phenomenon can be explained by the creation of Cu–Fe 3 O 4 interfaces present in the iron oxides of small crystallite sizes. Thorough characterizations, such as advanced electron microscopic, in situ powder X-ray diffractions, in situ diffuse reflectance infrared Fourier transform spectroscopy, and computational studies, suggest strong electronic interactions between the different metal species, facilitated reductions of the individual oxides, and more favorable CO activation at the interfacial sites, all accounting for the promoted activity. [Display omitted] • Influence of Fe 3 O 4 crystallite size in water-gas shift reaction was examined. • Performance of Cu/Fe 3 O 4 in water-gas shift reaction was studied. • The formation of Cu–Fe 3 O 4 interfaces existed on small Fe 3 O 4 crystals. • Promotional effect of Cu was only found on small Fe 3 O 4 crystals. [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]

Platinum-based catalysts that have long been used as the anodes for the formic acid electro-oxidation (FAO) in the direct formic acid fuel cells (DFAFCs) were susceptible to retrogradation in performance due to CO poisoning that impaired the technology transfer in industry. This work is designed to overcome this challenge by amending the Pt surface sequentially with nanosized cobalt (nano-CoOx, fibril texture of ca. 200 nm in particle size) and iron (nano-FeOx, nanorods of particle size and length of 80 and 253 nm, respectively) oxides. This enriched the Pt surface with oxygenated groups that boosted FAO and mitigated the CO poisoning. The unfilled d-orbitals of the transition metals and their tendency to vary their oxidations states presumed their participation in a faster mechanism of FAO. Engineering the Pt surface in this FeOx/CoOx/Pt hierarchy resulted in a remarkable activity toward FAO, that exceeded four times that of the Pt catalyst with up to ca. 2.5 times improvement in the catalytic tolerance against CO poisoning. This associated a ca. − 32 mV shift in the onset potential of FAO which increased to − 40 mV with a post-activation of the same catalyst at − 0.5 in 0.2 mol L–1 NaOH, displaying the catalyst's competitiveness in reducing overpotentials in DFAFCs. It also exhibited a favorable amelioration in the catalytic durability in long-termed chronoamperometric electrolysis. The electrochemical impedance spectroscopy and the CO stripping voltammetry were employed to elucidate the origin of enhancement. [ABSTRACT FROM AUTHOR]

In this study, various constraints of Cd toxicity on growth, morpho-anatomical characters along with physiological and biochemical metabolic processes of Solanum melongena L. plants were analyzed. Conversely, ameliorative role of iron oxide nanoparticles (FeONPs) was examined against Cd stress. For this purpose, the following treatments were applied in completely randomized fashion; 3 mM CdCl2 solution applied with irrigation water, 40 and 80 ppm solutions of FeONPs applied via foliar spray. Regarding the results, Cd caused oxidative damage to plants' photosynthetic machinery, resulting in elevated levels of stress-markers like malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolytic leakage (EL) along with slight increase in antioxidants activities, including glutathione (GsH), ascorbate (AsA), catalases (CAT), peroxidases (POD), superoxide dismutase (SOD), and ascorbate peroxidases (APX). Also, high Cd level in plants disturb ions homeostasis and reduced essential minerals uptake, including Ca and K. This ultimately reduced growth and development of S. melongena plants. In contrast, FeONPs supplementations improved antioxidants (enzymatic and non-enzymatic) defenses which in turn limited ROS generation and lowered the oxidative damage to photosynthetic machinery. Furthermore, it maintained ionic balance resulting in enhanced uptake of Ca and K nutrients which are necessary for photosynthesis, hence also improved photosynthesis rate of S. melongena plants. Overall, FeONPs foliar spray effectively mitigated Cd toxicity imposed on S. melongena plants. [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]

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]

In this paper, two types of iron oxide nanomaterial (Fe3O4) and nanocomposite (T-Fe3O4) were created from the bio-waste mass of tangerine peel. These two materials were utilized for adsorption tests to remove cefixime (CFX) from an aqueous solution. Before the adsorption application, both adsorbents have been characterized by various characterizations such as XRD, FTIR, VSM, TEM, and FESEM. The mesoporous nano-crystalline structure of Fe3O4 and T-Fe3O4 nanocomposite with less than 100-nm diameter is confirmed. The adsorption of the obtained adsorbents was evaluated for CFX removal by adjusting several operation parameters to optimize the removal. The optimal conditions for CFX removal were found to be an initial concentration of 40 and 50 mg/L, a dosage of 0.25 mg/50 mL, a contact time of 120 min, and a pH of 5. These settings resulted in qe max values of 41.322 and 56.49 mg g−1 onto Fe3O4 and T-Fe3O4, respectively. [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]

Photothermal therapy (PTT) can overcome cancer treatment resistance by enhancing the cell membrane permeability, facilitating drug accumulation, and promoting drug release within the tumor tissue. Iron oxide nanoparticles (IONPs) have emerged as effective agents for PTT due to their unique properties and biocompatibility. Approved for the treatment of anemia, as MRI contrast agents, and as magnetic hyperthermia mediators, IONPs also offer excellent light-to-heat conversion and can be manipulated using external magnetic fields for targeted accumulation in specific tissue. Optimizing parameters such as the laser wavelength, power density, shape, size, iron oxidation state, functionalization, and concentration is crucial for IONPs' effectiveness. In addition to PTT, IONPs enhance other cancer treatment modalities. They improve tumor oxygenation, enhancing the efficacy of radiotherapy and photodynamic therapy. IONPs can also trigger ferroptosis, a programmed cell death pathway mediated by iron-dependent lipid peroxidation. Their magneto-mechanical effect allows them to exert a mechanical force on cancer cells to destroy tumors, minimizing the damage to healthy tissue. This review outlines strategies for the management of the photothermal performance and PTT efficiency with iron oxide nanoparticles, as well as synergies with other cancer therapies. [ABSTRACT FROM AUTHOR]

Biogas conversion is a renewable alternative for producing hydrogen. In this work, dry reforming of simulated biogas was performed in a 1 kW th continuous chemical looping reforming (CLR) unit in which the oxygen required for the partial oxidation of biogas to CO and H 2 is supplied by an oxygen carrier. The performance of two different oxygen carriers (an iron oxide-based residue and a synthetic material based on an iron-manganese mixed oxide) was evaluated. The residue was capable of performing the dry reforming of biogas to a larger extent than the synthetic oxygen carrier. To enhance hydrogen yield, NiO addition was also considered with both materials. The presence of NiO increased methane conversion and H 2 selectivity for both oxygen carriers. A value of approximately 2.6 mol H 2 /mol CH 4 was achieved with both materials with the presence of only 2.7 wt% NiO in the bed. • Dry-CLR of biogas was evaluated in a 0.5 kW th chemical looping unit. • Two Fe-based oxygen carriers tested: one residue and one iron-manganese mixed oxide. • The residue performed the dry reforming of biogas in a larger extent. • NiO addition to both oxygen carriers increased methane conversion and H 2 selectivity. • Yield of 2.6 mol H 2 /molCH 4 with both materials with 2.7 wt% NiO in the bed. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles were synthesized by co-precipitation using three different iron salt stoichiometric mole ratios. Powder X-ray diffraction patterns revealed the inverse cubic spinel structure of magnetite iron oxide. Transmission electron microscopic images showed Fe3O4 nanoparticles with different shapes and average particle sizes of 5.48 nm for Fe3O4-1:2, 6.02 nm for Fe3O4-1.5:2, and 6.98 nm for Fe3O4-2:3 with an energy bandgap of 3.27 to 3.53 eV. The as-prepared Fe3O4 nanoparticles were used as photocatalysts to degrade brilliant green (BG), rhodamine B (RhB), indigo carmine (IC), and methyl red (MR) under visible light irradiation. The photocatalytic degradation efficiency of 80.4% was obtained from Fe3O4-1:2 for brilliant green, 61.5% from Fe3O4-1.5:2 for rhodamine B, and 77.9% and 73.9% from Fe3O4-2:3 for both indigo carmine and methyl red. This indicates that Fe3O4-2:3 is more efficient in the degradation of more than one dye. This study shows that brilliant green degrades most effectively at pH 9, rhodamine B degrades best at pH 6.5, and indigo carmine and methyl red degrade most efficiently at pH 3. Recyclability experiments showed that the Fe3O4 photocatalysts can be recycled four times and are photostable. [ABSTRACT FROM AUTHOR]

The study analyzes the black color factors of black-burnished pottery excavated from the Pungnap Fortress and the Seokchon Tomb during the Hanseong period of the Baekje Kingdom. The current hypothesis surrounding the pottery's black color factors suggests the use of magnetite, manganese oxide, and carbon. To compare the results of the black pottery, red pottery was used as the control group. To identify these black color factors, each hypothesis was investigated using several spectroscopic techniques. However, it was difficult to detect sufficient magnetite and manganese oxide on the surface of the black pottery to account for its black color. In contrast, a larger amount of carbon was located on the surface and core of the black pottery compared to the red pottery. These results indicate that the black factors can be credibly attributed to carbon rather than to magnetite or manganese oxide. The firing temperature of the black-burnished pottery was estimated from the mineral composition based on X-ray diffraction, and the firing atmosphere was deduced from the redox conditions based on the reduction index from Mössbauer spectroscopy. In addition, seven pieces of pottery excavated from Gunsu-ri Temple Site and Buyeo Ancient Tomb from the Sabi period of Baekje were investigated and compared the five pieces of pottery from the Hanseong period. Although the results were based on a limited number of potteries, various firing temperatures and redox atmosphere for pottery from the Hanseong and Sabi periods were carefully proposed. [ABSTRACT FROM AUTHOR]

Structured adsorbents have gained significant importance in gas separation applications due to their ability to fine‐tune mass and heat transfer and lower pressure drop across the bed. This study presents a ferromagnetic compressible hybrid structured adsorbent, allowing regeneration via magnetic induction heating. A compressible melamine sponge is coated with the CO2‐selective Ni‐MOF‐74 adsorbent and Fe3O4 as a ferromagnetic susceptor, capable of dissipating heat instantaneously in an alternating electromagnetic field. Taking advantage of these properties, the potential of rapid CO2 capture and thermal regeneration via magnetic induction swing adsorption is investigated. The successful incorporation of both ingredients on the melamine sponge is confirmed via SEM‐EDX and XRD analysis. Breakthrough experiments with a CO2/CH4‐mixture are performed. The selective property of Ni‐MOF‐74 toward CO2 is retained, with the composite showing a capacity of 1.89 mmol CO2/g. The compressible nature of the melamine sponge allowed for an improvement of 79% in the volumetric capacity of the adsorbent bed and a higher heating rate. In regard to regeneration, within 1 min of subjecting the structured composite to the alternating magnetic field, an efficient desorption (>90%) of CO2 is achieved. Overall, a ferromagnetic compressible hybrid structured adsorbent is presented for fast cyclic gas‐phase separation processes. [ABSTRACT FROM AUTHOR]

The features of glass batch preparation in the production of colorless sheet glass with increased transparency are considered. A non-standard algorithm for dosing and loading selenium, cobalt oxide, erbium oxide, and iron oxide into the mixer was proposed. [ABSTRACT FROM AUTHOR]

Hyperthermia therapy refers to the elevating of a region in the body for therapeutic purposes. Different techniques have been applied for hyperthermia therapy including laser, microwave, radiofrequency, ultrasonic, and magnetic nanoparticles and the latter have received great attention in recent years. Magnetic hyperthermia in cancer therapy aims to increase the temperature of the body tissue by locally delivering heat from the magnetic nanoparticles to cancer cells with the aid of an external alternating magnetic field to kill the cancerous cells or prevent their further growth. This review introduces magnetic hyperthermia with magnetic nanoparticles. It includes the mechanism of the operation and magnetism behind the magnetic hyperthermia phenomenon. Different synthesis methods and surface modification to enhance the biocompatibility, water solubility, and stability of the nanoparticles in physiological environments have been discussed. Recent research on versatile types of magnetic nanoparticles with their ability to increase the local temperature has been addressed. [ABSTRACT FROM AUTHOR]

Infectious coryza (IC) is an acute upper respiratory disease of chicken caused by Avibacterium (A.) paragallinarum. This disease results in an increased culling rate in meat chicken and a marked decrease in egg production (10% to more than 40%) in laying and breeding hens. Vaccines were first used against IC and effectively controlled the disease. Nanotechnology provides an excellent way to develop a new generation of vaccines. NPs have been widely used in vaccine design as adjuvants and antigen delivery vehicles and as antibacterial agents; thus, they can be used as inactivators for bacterial culture. In this research, the antibacterial effects of several nanoparticles (NPs), such as silicon dioxide with chitosan (SiO2-CS), oleoyl-chitosan (O.CS), silicon dioxide (SiO2), and iron oxide (Fe3O4), on A. paragallinarum were studied. Additionally, different A. paragallinarum vaccines were made using the same nanomaterials at a concentration of 400 µg/ml to help control infectious coryza disease in chicken. A concentration of 400 µg/ml of all the NPs tested was the best concentration for the inactivation of A. paragallinarum. Additionally, this study showed that the infectious coryza vaccine adjuvanted with SiO2 NPs had the highest immune response, followed by the infectious coryza vaccine adjuvanted with Fe3O4 NPs, the infectious coryza vaccine adjuvanted with SiO2-CS NPs, and the infectious coryza vaccine adjuvanted with O.CS NPs in comparison with the infectious coryza vaccine adjuvanted with liquid paraffin (a commercial vaccine). [ABSTRACT FROM AUTHOR]

This work presents a new and facile route for the preparation of iron oxide-based catalysts supported on alumina, which enables the targeted synthesis of catalysts with an increased amount of isolated tetrahedrally coordinated iron centers compared to a conventional impregnation procedure, and therefore leads to an increase in activity for CO oxidation reaction. By a multi-step impregnation–calcination protocol, the catalysts were synthesized with iron loadings of between 1 and 10 wt%, and their catalytic activity was then compared with a 10 wt% loaded catalyst prepared by conventional single impregnation. With a loading of 8 wt%, the presented catalysts showed an improved catalytic activity regarding light-off and full conversion temperatures compared to this reference. Through the application of several analytical methods (PXRD, PDF, DRUVS, SEM, XAFS), the improved catalytic activity can be correlated with an increased amount of isolated iron centers and a significantly reduced fraction of agglomerates or particles. [ABSTRACT FROM AUTHOR]

The creation of iron oxide nanostructures with complementary functions has emerged as a requirement for more efficient preclinical nanoparticle-mediated biological research. The physical and magnetic properties of nanoparticles for certain applications are determined by the particle morphology and size, which are crucial factors. We present a method for producing magnetite (Fe3O4) nanoclusters of uniform size by a simple and cost-effective solvothermal process, utilising oleic acid (OA) as the coordinating ligand. The nanocluster sizes are altered by manipulating the temperature during the solvothermal process. Three separate sets of Fe3O4 nanoclusters are synthesised and characterised. The X-ray diffraction (XRD) spectrum exhibits a singular phase characterised by a cubic spinel structure. The particle sizes in the nano range were verified by FESEM, and the interplanar spacing measured by TEM is consistent with that determined by XRD. The confirmation of nanocluster formation was achieved through the utilisation of FESEM and AFM images. The rising temperature correlates with the creation of nanoclusters. The rise in reaction temperature resulted in an augmentation of the size of the crystallite, the shape of nanocrystals, and a rise in the value of saturation magnetization. A high Ms from the magnetic property study confirmed that all the synthesised materials are superparamagnetic. The favourable magnetic characteristics and biocompatibility of the synthesised nanoclusters allow them suitable for biomedical applications. [ABSTRACT FROM AUTHOR]

A bauxite mining waste—partially lateralized khondalite (PLK) rock, was utilized as the feedback for the production of filling material in paper industries for brightening the papers. This product was isolated as the solid residue after leaching of iron ferrooxides (Fe2O3) from the bauxite mining waste matrix by using oxalic acid and hydrochloric acid through a synergistic effect. The leaching or extraction process of Fe2O3 was optimized using the concentration of Hydrochloric acid, temperature and extraction time as process variables in the range of 1–3.5 M, 50–90 °C, and 30–240 min, respectively. The extraction was performed with 0.5 Molar concentration of oxalic acid. From the optimization of iron oxide leaching, it was found that 2 M Hydrochloric acid along with 0.5 M oxalic acid reacted at 70 °C with a reaction period of 240 min resulted 64–65% Fe2O3 extraction efficiency. The solid residue obtained from the optimized conditions was characterized using several physicochemical characterization tools such as XRD, FTIR and SEM-EDAX, and also evaluated using the Bureau of Indian Standards for pulp and paper as well as ceramic industries. A statistical design named Box–Behnken is implemented by using Minitab to improve and optimize the process. The findings suggest that PLK rock can be used as a valuable economic resource for several industrial processes. [ABSTRACT FROM AUTHOR]

The effect of different substrate materials in the fabrication of an electrode intended for use in the water oxidation reaction is investigated. The electrocatalyst is nickel‐iron oxide (NiFeOx) which is deposited by chronoamperometry on nickel, iron, titanium, and stainless steel substrates. The process of electrodeposition is optimized to achieve the lowest overpotential for the water oxidation reaction. The four electrodes are characterized by scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), and glow‐discharge optical emission spectroscopy (GDOES) to describe the effect of the substrate on the nature of the electrocatalyst layer. Electrochemical tests in 1 m NaOH are applied on the four electrodes to assess the stability and the retention of the electrocatalytic properties of the whole electrode. All electrodes show similar overpotential of ≈0.3 V at 10 mA cm−2 implying that the substrate do not affect the electrocatalytic activity of the NiFeOx. After use, the overpotential increases in a range of 30–50 mV for nickel, iron, and titanium substrates, while stainless steel retains the lowest overpotential with an increase of 10 mV. This limited variation can be the effect of smaller NiFeOx nanoparticles compared to other substrates. XPS analysis reveals that after galvanostatic electrolysis, the oxidation state of Fe shifts slightly from Fe(II) to Fe(III), likely Fe3O4 and Fe2O3, while NiO/Ni2O3 change partially to Ni(OH)2. [ABSTRACT FROM AUTHOR]

Once dispersion and cytotoxicity issues are resolved, it has been proven that carbon nanotubes (CNTs) have great advantages in biomedical applications due to their unique properties. In this study, the superiority of carbon nanotubes was combined with magnetic targeting strategies, and a solution to the distribution problem in the aqueous media of the resulting CNTs decorated with iron oxide (mCNTs) was sought. A non‐covalent functionalization approach has been utilized to overcome this fundamental drawback of mCNTs. Conjugates of polyethylene glycol monomethyl ether and 9‐ fluorenyl methyl chloroformate (Fmoc) amino acids were used to coat the lateral surfaces of mCNTs, making them more water‐soluble. The selected Fmoc amino acids have different numbers of aromatic rings, which is known to affect the coating efficiency in non‐covalent functionalization and therefore, the dispersion behavior of the CNTs. Their coating yields, dispersion behaviors, magnetism, charge, and size properties have been determined. All coated mCNT samples displayed superparamagnetic behavior. Dispersion tests showed a promise to increase the stability of mCNTs with this approach. Moreover, we demonstrated that the functionalization of mCNTs affects cell viability in a dose‐dependent manner. The main finding of this study is that mCNTs can be successfully functionalized with Fmoc amino acid‐modified polyethylene glycol. [ABSTRACT FROM AUTHOR]

We report the synthesis of iron oxide nanoparticles using solution combustion synthesis, focusing on the controlled manipulation of material characteristics, such as particle size, phase composition, and magnetic properties, by applying external inert gas pressure. It was shown that variation of nitrogen gas pressure in the reactor in the range 0.1 to 1.1 MPa changed the time-temperature history of the process and resulted in the gradual change of phase composition of the fabricated materials along the FeO → FeO∙Fe2O3 → Fe2O3 route. The particle size varied in the 50–400 nm range, with a maximum for powder synthesized at a pressure of 0.25 MPa. For magnetic fluid hyperthermia, the critical parameter is specific loss power. It was demonstrated that this parameter can be optimized by gas pressure variation. The maximum specific loss power measured under conditions suitable for magnetic hyperthermia (magnetic field 33.5 mT and frequency 259.6 kHz) appears to be 174 W/g. The proposed innovative approach is an effective tool for controlling the synthesis of various nanoparticles with desired properties. Highlights: Inert gas pressure controls material's structure fabricated by solution combustion synthesis. A raise in gas pressure leads to a vary in phase composition along the FeO → Fe3O4 → Fe2O3 line. The particle size alters in 50–400 nm range with minimum for that made at a pressure of 1.1 MPa. The specific loss power under magnetic hyperthermia conditions was as high as 174 W/g. The innovative approach can be used for synthesis of various nanoparticles with desired properties. [ABSTRACT FROM AUTHOR]

Wenyu Zhang,1,* Linquan Li,1,* Yaguang Wu,1 Chengzhilin Li,1 Zi’ang Xu,1 Nianlei Zhang,1 Xinyu Wang,1 Yingchun Zhao,1 Tingjian Zu,1 Qingbin He,1 Jianwei Jiao,2 Runxiao Zheng1 1School of Clinical and Basic Medical Sciences, Medical Science and Technology Innovation Center, Shandong Provincial Hospital, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250000, People’s Republic of China; 2State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, People’s Republic of China*These authors contributed equally to this workCorrespondence: Runxiao Zheng, Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 250000, People’s Republic of China, Email zhengrunxiao@sdfmu.edu.cn Jianwei Jiao, State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, People’s Republic of China, Email jwjiao@ioz.ac.cnIntroduction: Immunotherapy has led to a paradigm shift in reinvigorating treatment of cancer. Nevertheless, tumor associated macrophages (TAMs) experience functional polarization on account of the generation of suppressive metabolites, contributing to impaired antitumor immune responses.Methods: Hence, metabolic reprogramming of tumor microenvironment (TME) can synergistically improve the efficacy of anti-tumor immunotherapy. Herein, we engineered an iron-based nanoplatform termed ERFe3O4 NPs. This platform features hollow Fe3O4 nanoparticles loaded with the natural product emodin, the outer layer is coated with red blood cell membrane (mRBCs) inserted with DSPE-PEG2000-galactose. This effectively modulates lactate production, thereby reversing the tumor immune suppressive microenvironment (TIME).Results: The ERFe3O4 NPs actively targeted TAMs on account of their ability to bind to M2-like TAMs with high expression of galectin (Mgl). ERFe3O4 NPs achieved efficient ability to reverse TIME via the production of reducing lactate and prompting enrichment iron of high concentrations. Furthermore, ERFe3O4 NPs resulted in heightened expression of CD16/32 and enhanced TNF-α release, indicating promotion of M1 TAMs polarization. In vitro and in vivo experiments revealed that ERFe3O4 NPs induced significant apoptosis of tumor cells and antitumor immune response.Discussion: This study combines Traditional Chinese Medicine (TCM) with nanomaterials to synergistically reprogram TAMs and reverse TIME, opening up new ideas for improving anti-tumor immunotherapy. Keywords: metabolic immunotherapy, nanoparticles, reprograming, iron oxide, macrophages

Abstract Platinum-based catalysts that have long been used as the anodes for the formic acid electro-oxidation (FAO) in the direct formic acid fuel cells (DFAFCs) were susceptible to retrogradation in performance due to CO poisoning that impaired the technology transfer in industry. This work is designed to overcome this challenge by amending the Pt surface sequentially with nanosized cobalt (nano-CoOx, fibril texture of ca. 200 nm in particle size) and iron (nano-FeOx, nanorods of particle size and length of 80 and 253 nm, respectively) oxides. This enriched the Pt surface with oxygenated groups that boosted FAO and mitigated the CO poisoning. The unfilled d-orbitals of the transition metals and their tendency to vary their oxidations states presumed their participation in a faster mechanism of FAO. Engineering the Pt surface in this FeOx/CoOx/Pt hierarchy resulted in a remarkable activity toward FAO, that exceeded four times that of the Pt catalyst with up to ca. 2.5 times improvement in the catalytic tolerance against CO poisoning. This associated a ca. − 32 mV shift in the onset potential of FAO which increased to − 40 mV with a post-activation of the same catalyst at − 0.5 in 0.2 mol L–1 NaOH, displaying the catalyst's competitiveness in reducing overpotentials in DFAFCs. It also exhibited a favorable amelioration in the catalytic durability in long-termed chronoamperometric electrolysis. The electrochemical impedance spectroscopy and the CO stripping voltammetry were employed to elucidate the origin of enhancement.

Abstract In this study, various constraints of Cd toxicity on growth, morpho-anatomical characters along with physiological and biochemical metabolic processes of Solanum melongena L. plants were analyzed. Conversely, ameliorative role of iron oxide nanoparticles (FeONPs) was examined against Cd stress. For this purpose, the following treatments were applied in completely randomized fashion; 3 mM CdCl2 solution applied with irrigation water, 40 and 80 ppm solutions of FeONPs applied via foliar spray. Regarding the results, Cd caused oxidative damage to plants’ photosynthetic machinery, resulting in elevated levels of stress-markers like malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolytic leakage (EL) along with slight increase in antioxidants activities, including glutathione (GsH), ascorbate (AsA), catalases (CAT), peroxidases (POD), superoxide dismutase (SOD), and ascorbate peroxidases (APX). Also, high Cd level in plants disturb ions homeostasis and reduced essential minerals uptake, including Ca and K. This ultimately reduced growth and development of S. melongena plants. In contrast, FeONPs supplementations improved antioxidants (enzymatic and non-enzymatic) defenses which in turn limited ROS generation and lowered the oxidative damage to photosynthetic machinery. Furthermore, it maintained ionic balance resulting in enhanced uptake of Ca and K nutrients which are necessary for photosynthesis, hence also improved photosynthesis rate of S. melongena plants. Overall, FeONPs foliar spray effectively mitigated Cd toxicity imposed on S. melongena plants.

Abstract The study analyzes the black color factors of black-burnished pottery excavated from the Pungnap Fortress and the Seokchon Tomb during the Hanseong period of the Baekje Kingdom. The current hypothesis surrounding the pottery’s black color factors suggests the use of magnetite, manganese oxide, and carbon. To compare the results of the black pottery, red pottery was used as the control group. To identify these black color factors, each hypothesis was investigated using several spectroscopic techniques. However, it was difficult to detect sufficient magnetite and manganese oxide on the surface of the black pottery to account for its black color. In contrast, a larger amount of carbon was located on the surface and core of the black pottery compared to the red pottery. These results indicate that the black factors can be credibly attributed to carbon rather than to magnetite or manganese oxide. The firing temperature of the black-burnished pottery was estimated from the mineral composition based on X-ray diffraction, and the firing atmosphere was deduced from the redox conditions based on the reduction index from Mössbauer spectroscopy. In addition, seven pieces of pottery excavated from Gunsu-ri Temple Site and Buyeo Ancient Tomb from the Sabi period of Baekje were investigated and compared the five pieces of pottery from the Hanseong period. Although the results were based on a limited number of potteries, various firing temperatures and redox atmosphere for pottery from the Hanseong and Sabi periods were carefully proposed.

Abstract Infectious coryza (IC) is an acute upper respiratory disease of chicken caused by Avibacterium (A.) paragallinarum. This disease results in an increased culling rate in meat chicken and a marked decrease in egg production (10% to more than 40%) in laying and breeding hens. Vaccines were first used against IC and effectively controlled the disease. Nanotechnology provides an excellent way to develop a new generation of vaccines. NPs have been widely used in vaccine design as adjuvants and antigen delivery vehicles and as antibacterial agents; thus, they can be used as inactivators for bacterial culture. In this research, the antibacterial effects of several nanoparticles (NPs), such as silicon dioxide with chitosan (SiO2-CS), oleoyl-chitosan (O.CS), silicon dioxide (SiO2), and iron oxide (Fe3O4), on A. paragallinarum were studied. Additionally, different A. paragallinarum vaccines were made using the same nanomaterials at a concentration of 400 µg/ml to help control infectious coryza disease in chicken. A concentration of 400 µg/ml of all the NPs tested was the best concentration for the inactivation of A. paragallinarum. Additionally, this study showed that the infectious coryza vaccine adjuvanted with SiO2 NPs had the highest immune response, followed by the infectious coryza vaccine adjuvanted with Fe3O4 NPs, the infectious coryza vaccine adjuvanted with SiO2-CS NPs, and the infectious coryza vaccine adjuvanted with O.CS NPs in comparison with the infectious coryza vaccine adjuvanted with liquid paraffin (a commercial vaccine).

The nitrate contamination of water resources is a serious environmental problem, which may be solved by nitrate sorption onto magnetic nanoparticles. In this study, the effects of Fe3O4 magnetic nanoparticles on nitrate removal were investigated. Fe3O4 was synthesized by a co-precipitation method and used as an adsorbent for nitrate removal. pH, adsorbent dosage, and contact time were considered as the main variables. The effective ranges of these variables were chosen as pH = 4–10, adsorbent dose = 0.5–1.5 g/L, and contact time = 30–90 min. The optimization study was conducted using the Box–Behnken statistical design method. According to the analysis of variance table, it can be concluded that the model is ‘significant’ and the value of R2 was 0.99. The results of the study show that the maximum nitrate removal efficiency was about 91.02%. This was obtained at pH 7, using a dose of 1.3 g/Lof Fe3O4, and a contact time of 28 min. HIGHLIGHTS It is a nitrate removal study.; It is an optimization study.; It includes nanoparticles.;

The investigation and clarification of the properties of surface-functionalized superparamagnetic nanoparticles in a biological environment are key challenges prior to their medical applications. In the present work, electron paramagnetic resonance spectroscopy (EPR) combined with the spin labeling technique was utilized to better understand the behavior of nitroxides attached to magnetite nanoparticles dispersed in body fluid. EPR spectra of spin-labeled, silane-coated Fe3O4 nanoparticles in human serum and whole blood were recorded and analyzed for both room- and low-temperature values. In all cases, the obtained EPR signal consisted of a broad line from magnetite cores and a characteristic signal from the attached 4-Amino-2,2,6,6-tetramethylpiperidine-1-oxyl (4-amino-TEMPO). Even for liquid samples, the anisotropic components of magnetic tensors did not fully average out, which was reflected in the differences in the intensity of three narrow hyperfine lines from nitroxide. At 230 K the irregular slow-motion signal from the attached radical was also simulated using the EasySpin toolbox, which allowed to determine the parameters related to magnetic tensors and the dynamics of the spin label. The study showed that the anisotropy of the motion of the spin label 4-amino-TEMPO reflects its interactions with the surrounding medium and the manner of the attachment of the nitroxide to the surface of nanoparticles.

Introduction. The use of building materials with photocatalytically active additives is considered as a promising solution to environmental and economic problems of the urban environment. In the field of building materials science the necessity of studying the microstructure of self-cleaning building materials and the influence of impurities on the efficiency of self-cleaning of materials with photocatalytically active additives is determined.Materials and methods. Red gypsum (production waste with photocatalytically active impurities), cement, building gypsum, microsilica, synthesized photocatalytically active titanium oxide – silicon oxide additive, and iron-based pigments were used. Tablet specimens of gypsum-cement-pozzolanic binder with various photocatalytically active components were made: photocatalyst additive, pigments, photocatalytically active oxide impurities. The microstructure of the specimens and the distribution of titanium and iron elements were studied using scanning electron microscopy. The efficiency of self-cleaning was determined by the change in the contact angle of a water drop on a surface coated with oleic acid.Results. The efficiency of self-cleaning of specimens with added and impurity photocatalytically active components was determined. The influence of added impurities on the structure of the material and the influence of the type and concentration of impurities on the efficiency of self-cleaning were revealed.Conclusions. Titanium oxide photocatalyst additive at a concentration of 4.4 % provides high self-cleaning efficiency, evenly distributed throughout the material without affecting the structure of the forming binder stone. Pigment (iron (III) oxide) provides sufficient self-cleaning efficiency at a concentration of 2–9 %, at concentrations of more than 2 % it is distributed unevenly, providing a small increase in self-cleaning efficiency indicators. With the joint introduction of titanium and iron oxides, deterioration in self-purification is observed due to the high degree of recombination of electron – hole pairs. Red gypsum with impurity oxides of titanium and iron has shown a high efficiency of self-cleaning, has a uniform distribution of impurities that do not have a clear effect on the structure of the material.

This work presents the green synthesis of iron oxide nanoparticles (IONPs) using Baccharis salicifolia extract and their incorporation in mesoporous silica MCM-41, obtaining an MCM-41@IONP composite. The MCM-41@IONP composite was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), nitrogen adsorption and desorption, scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The use of the natural reducing agent Baccharis salicifolia resulted in nanoparticles with an average size of 31 nm. Furthermore, we showcase the application of the MCM-41@IONP nanocomposite in a metal–insulator–semiconductor (MIS) diode, which was fabricated at room temperature. The current–voltage and capacitance–voltage curves of the MIS diode were carefully measured and subjected to detailed analysis. The results demonstrate the potential utility of MCM-41@IONP nanocomposite-based MIS diodes, suggesting their applicability in the design of biosensors or as discrete components in electronic devices.

Rapid advancements in nanotechnology have expanded its applications and synergistic impact on modern nanosystems. The comprehensive assessment of nanomaterials' safety for human exposure has become crucial and heightened. In addition to the characterization of cell proliferation and apoptosis, probing the implication of autophagy is vital for understanding the ramification of nanomaterials. Hence, HEK-293 kidney cells were employed to understand the changes in induction and perturbation of autophagy in cells by iron oxide (Fe3O4) and silica (SiO2) nanoparticles. Interestingly, Fe3O4 worked as a potent modulator of the autophagy process through its catalytic performance, which can develop better than that of SiO2 nanoparticles mechanism, stressing their therapeutic implication in the understanding of cell behaviors. The quantification of reactive oxygen species (ROS) was measured along with the process of autophagy during cell growth. This modulated autophagy will help in cell fate determination in complementary therapy for disease treatment, provide a clinical strategy for future study. [ABSTRACT FROM AUTHOR]

Air pollution is an environmental factor associated with an increased risk of neurodegenerative diseases, such as Alzheimer's and Parkinson's, characterized by decreased cognitive abilities and memory. The limited models of sporadic Alzheimer's disease fail to replicate all pathological hallmarks of the disease, making it challenging to uncover potential environmental causes. Environmentally driven models of Alzheimer's disease are thus timely and necessary. We used live-cell confocal fluorescent imaging combined with high-resolution stimulated emission depletion (STED) microscopy to follow the response of retinoic acid-differentiated human neuroblastoma SH-SY5Y cells to nanomaterial exposure. Here, we report that exposure of the cells to some particulate matter constituents reproduces a neurodegenerative phenotype, including extracellular amyloid beta-containing plaques and decreased neurite length. Consistent with the existing in vivo research, we observed detrimental effects, specifically a substantial reduction in neurite length and formation of amyloid beta plaques, after exposure to iron oxide and diesel exhaust particles. Conversely, after exposure to engineered cerium oxide nanoparticles, the lengths of neurites were maintained, and almost no extracellular amyloid beta plaques were formed. Although the exact mechanism behind this effect remains to be explained, the retinoic acid differentiated SH-SY5Y cell in vitro model could serve as an alternative, environmentally driven model of neurodegenerative diseases, including Alzheimer's disease. [ABSTRACT FROM AUTHOR]