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The primary objective of this investigation was to develop a new nanocatalyst that could produce materials with a lower sulfur content, thereby reducing its environmental harm. To achieve this, the researchers used the sol‐gel method to synthesize a heterogeneous nanocatalyst by attaching sandwich‐type polyoxotungstate [(CuW9O34)2Cu4(H2O)2−10] (denoted as Cu6W18O70) clusters on the surface of copper ferrite nanoparticles (CuFe2O4 NPs). To characterize the nanocatalyst, several analysis techniques were employed, including Fourier transform infrared spectroscopy, ultraviolet‐visible, powder X‐ray diffraction, and scanning electron microscope. The oxidative desulfurization of hazardous sulfur‐containing real and model fuel oils was effectively catalyzed by the Cu6W18O70⊂CuFe2O4 nanocatalyst. According to the experimental findings, the best efficiencies in oxidation reaction were achieved in 1 h contracting time at 35°C, which was as high as 95%. The Cu6W18O70⊂CuFe2O4 nanocatalyst exhibited impressive removal rates (%) on dibenzothiophene (C12H8S), benzothiophene (C8H6S), and thiophene (C4H4S) of model fuels, with figures reaching 97%, 96% and, 96% respectively. Furthermore, multiple recycling of the uniform nanocatalyst can be achieved effortlessly through filtration, without experiencing any notable decline in activity. Therefore, the authors suggest that this study will pave the way for the widely used mentioned nanocatalyst in the practical and workable organization of petroleum fractions. [ABSTRACT FROM AUTHOR]

To investigate the reinforcing effect of nanoflower‐like hydroxyapatite (NFHA) in resin‐based dental composites, we synthesized a novel NFHA using microwave irradiation (MW), hydrothermal treatment (HT), and sonochemical synthesis (SS). Silanized NFHA was then used as the reinforcing filler in dental resin composites. We characterized the structure and morphology of various HA nanostructures using x‐ray diffraction, scanning electron microscope, and TEM. The mechanical performance of dental resin composites reinforced with silanized NFHA was measured using a universal testing machine. Spherical HA, synthesized through chemical precipitation (CP), served as the control group. One‐way analysis of variance was employed for the statistical analysis of the acquired data. The results demonstrate that the nanoflower morphology significantly was improved mechanical and physical properties. After conducting trials, the NFHA synthesized using MW and HT showed a substantial enhancement in mechanical and physical properties compared to the other structures. Therefore, it can be concluded that NFHA can serve as a novel reinforcing HA filler, providing regenerative properties to resin composites with sufficient mechanical strength. [ABSTRACT FROM AUTHOR]

This research aims at investigating the idea of anti‐bacterial self‐healing coatings based on polyurea formaldehyde microcapsules (MCs), with the repair agent being ZnO‐containing linseed oil. ZnO nanoparticles were added to the repair agent with the idea of developing an antibacterial coating. The idea was to entrap some ZnO nanoparticles inside microcapsules, aiming for some local release of ZnO nanoparticles where the coating is damaged. The corrosion resistances of the coatings were studied using the Tafel polarization test. The structure of the coating samples was evaluated using a scanning electron microscope. To check the antibacterial properties of ZnO‐containing self‐healing samples, Escherichia coli and Staphylococcus aureus bacteria were used. Results showed that ZnO nanoparticles were distributed not only inside microcapsules but also over the walls, inferring that overall protection can also be attained in addition to local anti‐bacterial performance. Results showed that the proposed multi‐functional coating has promising antibacterial and self‐healing responses. [ABSTRACT FROM AUTHOR]

The research aimed to prepare eco-friendly bio-nanocomposite films utilizing gelatin/ starch (GS), nano-ZnO, and Darbha grass extract via the solution casting method. Then, it was examined the mechanical and physical properties of different durations of sunlight exposure on the prepared films. The results indicated that up to 12 h of sunlight exposure led to increased film thickness, mechanical strength, and apparent density. Tensile strength increased from 4.8 to 34.8 MPa, and the average crystalline size of the nanoparticles was found to be 54.35 nm using scanning electron microscope. Compared with GS films, these bio-nanocomposite films exhibited lower moisture content, oil permeability, and enhanced water barrier properties. Moreover, they displayed significant UV absorption and profound antimicrobial activity against both gram-positive and gram-negative food borne pathogenic bacteria. The nano-ZnO/Darbha grass extract-based bio-nanocomposite films exhibited showed improved characteristics and could be applied in the field of food packaging application. [ABSTRACT FROM AUTHOR]

The areas of environmental cleanup and bacteria inactivation are particularly interesting in polymer-based nanomaterials because of their unique physicochemical properties. Conjugated polymer nanoparticles (CP NPs) have potential uses in the biological and environmental, but little is known about them. This study aimed to examine the efficacy of CP nanoparticles in the photocatalytic inactivation of S. aureus and E. coli under visible irradiation (λ ≤ 420 nm), with minor enhancements observed. The simple and one-step chemical oxidation technique was used to prepare CP nanoparticles. X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), Energy-dispersive X-ray (EDS), and Transmission electron microscopy (TEM) analyses were utilized to characterize the physicochemical properties of CP nanoparticles for comprehensive structural analysis. The synthesized CP nanoparticles exhibited outstanding photocatalytic disinfection capabilities, achieving a degradation of 98.6%. This research not only provides insights into the physical characteristics of CP nanoparticles but also illustrates their antibacterial efficacy against two different bacterial pathogens, namely S. aureus and E. coli. Therefore, this research highlights an eco-friendly and inexpensive preparation of conjugated polymer nanoparticles for a wide range of applications. [ABSTRACT FROM AUTHOR]

This study presents the effect of chitosan on the properties of zinc ferrite nanoparticles suitable for potential biomedical applications. The co‐precipitation method is employed to fabricate these bio‐composites that exhibit excellent microstructural properties. The X‐ray diffractometer (XRD) analysis confirms the presence of a cubic spinel structure in the zinc ferrite‐chitosan bio‐composites, indicative of their crystalline nature. Scanning electron microscope (SEM) imaging revealed spherical particles with a size distribution below 100 nm, demonstrating the successful synthesis of homogenous nanosized particles. Fourier transform infrared spectroscopy (FTIR) spectroscopy analysis identifies the active functional groups within the bio‐composites, providing valuable insights into the molecular structure and interactions present in the synthesized materials. The presence of chitosan is confirmed, highlighting its role in modifying the chemical composition and enhancing the biocompatibility of the samples. UV–vis absorption spectra analysis reveals that the samples exhibits absorbance within the visible range. Vibrating sample magnetometer (VSM) analysis demonstrates the superparamagnetic behavior of the samples. Remarkably, these formulated samples exhibit superparamagnetism with zero coercivity and a magnetization of ≈0.0125 emu g−1 at 5 kOe when doped with chitosan. These properties are crucial for potential biomedical applications making it a promising candidate for various biomedical applications. [ABSTRACT FROM AUTHOR]

Boehmite is one of the stable phases of alumina that is easily available, and it also has a variety of applications. Therefore in this work, for preparation of AlOOH, Sodium hydroxide (NaOH) solutions was added to aluminum nitrate nonahydrate (Al(NO3)3.9H2O) solution. Then, the surface of AlOOH was modified with (3‐aminopropyl)triethoxysilane (APTES), due to high condensation of hydroxyl groups on its surface. Then, di(pyridin‐2‐yl)methanone (di(PM)) was immobilized on the surface of modified AlOOH toward synthesis of immobilized Schiff‐base on AlOOH (di(PM)@AlOOH) as a heterogeneous Schiff‐base ligand. Finally, a palladium complex was immobilized on its surface (Pd‐di(PM)@AlOOH) as a reusable, practical, and novel nanocatalyst. Pd‐di(PM)@AlOOH was characterized by thermogravimetric analysis (TGA) analysis, Fourier‐transform infrared spectroscopy (FT‐IR), transmission electron microscopy (TEM), scanning electron microscope (SEM) imaging, energy‐dispersive X‐ray spectroscopy (EDS) analysis, wavelength‐dispersive X‐ray spectroscopy (WDX) analysis, and inductively coupled plasma (ICP) analysis. After the characterization of Pd‐di(PM)@AlOOH, its performance was used as a highly practical, stable, retrievable, and hybrid organic–inorganic catalyst in the C‐C coupling of the Suzuki reaction. The hot filtration study of Pd‐di(PM)@AlOOH revealed that it acts heterogeneously in the Suzuki reaction. We found that this catalyst can be recycled for five runs without palladium leaching, as studied by hot filtration test and ICP analysis. [ABSTRACT FROM AUTHOR]

Summary: The present study evaluated the production of galactooligosaccharides (GOSs) from lactose in both batch and continuous modes using nano‐immobilised β‐galactosidase. Mesoporous silicon dioxide nanoparticles were used to immobilise β‐galactosidase to enhance the stability and production of GOSs. The change in enzyme‐characteristics was assessed using Fourier‐transform infrared and scanning electron microscope analysis. The nano‐immobilisation increased the enzyme's substrate affinity, but decreased its hydrolytic activity. A significant increase (P < 0.05) in stability was observed across a wide range of temperature (30 °C–70 °C) and pH (5.0–8.0). Both forms of enzymes (free and nano‐immobilised enzymes) followed the zero‐order reaction in all temperatures, while the nano‐immobilised enzyme had the highest activation energy. The free and nano‐immobilised enzymes retained 64.65% and 77.82% of their initial activity after 90 days of storage, respectively. In a batch mode, the nano‐immobilised enzyme produced 2.35 times more GOSs than the free enzyme. The GOSs production remained consistent while the enzyme activity decreased by 12.7% after 5 cycles of operation. The continuous mode of production in a packed bed reactor achieved a GOSs yield of 16.92%. Overall, the nano‐immobilised enzyme showed better GOSs production under batch and continuous mode of operation. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic‐resistant bacterial infections is a principal threat to global health. Functionalization of nanomaterial with antibiotics is known as a useful method for increasing the effectiveness of existing antibiotics. In this study, vancomycin‐functionalized ZnFe2O4 nanocomposite (ZnFe2O4@Cell@APTES@Van) was synthesized, and its functional groups and particle size were characterized using Fourier‐transform infrared spectroscopy, thermogravimetric analysis, dynamic light scattering, scanning electron microscope, and transmission electron microscopy. The antibacteria activity of the synthesized nanocomposite was evaluated using minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli, Staphylococcus aureus, and methicillin‐resistant Staphylococcus aureus (MRSA). Cytotoxicity assay was done by 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide method. Characterization analyses of synthesized nanocomposite confirmed the binding of vancomysin on the surface of ZnFe2O4@Cell@APTES. Nanocomposite exhibited an aggregated semi‐spherical structure with hydrodynamic radii of ∼382 nm. In vitro antibacterial activity test showed that vancomycin and vancomycin functionalized ZnFe2O4 have no antibacterial effect against E. coli. S. aureus was sensitive to vancomycin and ZnFe2O4@Cell@APTES@Van NPs and ZnFe2O4 NPs did not improve vancomycin antibacterial activity against these bacteria. MRSA is resistant to vancomycin while ZnFe2O4@Cell@APTES@Van NPs was efficient in inhibiting MRSA growth. In summary, this study showed that attachment of vancomycin to ZnFe2O4 NPs was increased its antibacterial activity against MRSA. [ABSTRACT FROM AUTHOR]

Plant‐based nanoparticles (NPs) have found great interest among various scientist in the present era and used in various sector including medicine, agriculture, and food industry. The various chemical constituents of plants aid in the bioreduction of metal ions to a nanoscale. Among the various NPs synthesized, zinc oxide (ZnO) NPs hold a premier position. ZnO NPs have use in textile, cosmetic, diagnostics, optoelectronics, photocatalysis, diodes, and many other areas. NPs synthesized through green synthesis have a potentially greater role in treating clinical pathogens. Present investigations show a simple eco‐friendly method for the synthesis of ZnO NPs from the husk of sunflower seeds. Sunflower is an economically important crop, for the formation of edible oil. The husk is considered to be a waste, product in oil industry, however, the biomolecules present in sunflower husk can be used to produce ZnO NPs. Present investigations reveal formation of ZnO NPs and investigations of their structure through scanning electron microscope (SEM), X‐ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Their optical properties have been studied by ultraviolet–visible spectrophotometer (UV–Vis) and fluorophotometer. ZnO NPs have also been investigated for their potential phytoremedial properties. [ABSTRACT FROM AUTHOR]

Nanoparticle incorporation plays an active feature in heat transfer, ultimately enhancing the tribological process under boundary conditions of heat stress. Nanoparticles like zinc oxide (ZnO) and multiwall carbon nanotubes (MWCNT) are well known to significantly affect the cooling and lubrication applications, resulting in improved heat transfer and kinematic viscosity. The present work investigates the tribological performance of ZnO/MWCNTs hybrids as lubricant additive in the paraffinic type of mineral base oil of Group I (SN150) engine oil. The chemical composition of the modified and unmodified oil was examined by an inductively coupled plasma-optical emission spectrometer (ICP-OES), energy dispersive x-ray fluorescence (EDXRF) spectrometer, and Fourier-transform infrared spectroscopy (FTIR). A ring-ondisk tribotester was performed to investigate the tribological behaviour through the linear reciprocating mechanism alloy-steel contacts. The worn steel alloy surfaces morphology and chemical compositions were examined by scanning electron microscope (SEM), energy-dispersive x-ray spectroscopy (EDX), and 3D optical profilometer. Different ZnO/MWCNTs nanomaterial volumetric concentrations were examined in order to determine the most effective performance. According to the tribological results, ZnO/MWCNTs hybrid nanomaterials in the engine oil were found to have significantly higher friction temperature and antiwear capability than the base oil. A volumetric concentration of 3.00 wt% ZnO/MWCNTs nanomaterials to SN150 engine oil imparted excellent wear protection to the steel sample than the pure SN150 base oil. Based on the statistical analysis, the modified oil anti-wear performance was enhanced by reducing the wear loss by 80.5% and friction temperature by 55.8°C compared with the oil base. [ABSTRACT FROM AUTHOR]

Herein, 3D printing coupled with drug‐release systems introduces many advantages to bone‐regenerative medicine. In this research, hydrogel‐based nanocomposite inks comprising alginate/gelatin (Alg/Gel) matrix supplemented with mesoporous bioactive glass (MBG) and zeolite‐imidazole framework‐8 (ZIF‐8) nanoparticles are presented. A fixed wt% of mixed nanoparticles at MBG/ZIF weight ratios of 85:15 and 70:30 is added to Alg/Gel to prepare nanocomposite inks. All inks have shear‐thinning behavior, facilitating scaffolds' 3D printing via extrusion. Scaffolds' 3D spatial and nanocomposite microstructures are confirmed using field‐emission scanning electron microscope and energy‐dispersive X‐ray (FESEM/EDX) and Fourier transform infrared (FT‐IR). Shear punch testing indicates an enhanced shear strength of 85:15 samples in both dry (9.49 ± 0.23 MPa) and wet conditions (1.19 ± 0.16 MPa). After 1 month, nanocomposite scaffolds have a higher degradation rate (65%) than Alg/Gel (50%) in phosphate‐buffered saline. In vitro drug‐release study using UV–visible spectrophotometry exhibits a similar prolonged release profile for 85:15 and 70:30 nanocomposites compared to Alg/Gel. Due to its better mechanical performance, 85:15 is used for bioactivity and cellular tests. MBG provides bioactivity in simulated body fluid by the rapid development of hydroxyapatite validated by FESEM/EDX, XRD, and FT‐IR. Nanocomposite scaffolds exhibit significantly higher MG‐63 cell viability (>90%) than Alg/Gel. Finally, these scaffolds provide a potential additive‐manufacturing solution to bone tissue regeneration. [ABSTRACT FROM AUTHOR]

Three samples of Fe−S were prepared with different hydrothermal periods (6, 12, and 18 h). X‐ray diffraction (XRD) test showed that the first produced sample contained 42.3 wt % of magnetite, 35 wt % of greigite, and 22.7 wt % of pyrite phases. The same phases were formed during the second period but with different wt % ratios. The greigite increased to 67.8 wt % by the third period, while the magnetite and pyrite phases vanished and were associated with a low ratio of the presence of pyrrhotite and FeO2. Scanning electron microscope (SEM) images confirmed the formation of the nanoparticles. The increase in the hydrothermal time produced a reduction in the saturation magnetization (39.8 to 9.1) emu/g and the remanence magnetization (8 to 2.4) emu/g, and increasing in the coercivity. To assess the viability of Michigan Cancer Foundation‐7 (MCF‐7) and hemolytic disease of the fetus and newborn (HdFn) cells, a colorimetric assay for assessing cell metabolic activity (MTT) was applied to the third sample. The outcome verified iron sulfide's cytocompatibility against HdFn cells even at high concentrations and good anticancer activity against MCF‐7 cell lines. The result of the DPPH test confirmed that the third sample had antioxidant activity equivalent to that of ascorbic acid. [ABSTRACT FROM AUTHOR]

For commercial civil applications of laminated composite material, characterizations to forecast the interlaminar shear behavior and viscoelastic response across a wide temperature range are essential. In this study, the interlaminar shear strength (ILSS) of glass/epoxy (GE) composites dispersed with binary nanofillers nanosilica‐multilayer graphene (NS‐MLG) and nanosilica‐nanoclay (NS‐NC) was analyzed at an in‐situ testing temperature of 20, 70, and 110°C. Further, the viscoelastic property of the composites was studied using a dynamic mechanical thermal analyzer (DMTA) in the temperature range of 35–165°C. An increase in the ILSS value of around 9% and 10% was observed at room temperature for GE/MLG‐NS and GE/NC‐NS, respectively, compared to control GE composites. In contrast, the trend was seen to change at higher temperatures. There was a slight decrement in the storage modulus (E′) of GE/MLG‐NS and GE/NC‐NS composites in the glassy region compared to control GE composites. The mean Tg of the GE composite (control) was nearly 107.3°C when the E′ decline onset temperature was taken into account, but after the addition of MLG‐NS, it was 10.1°C below. The mean Tg of GE/NC‐NS was determined to be 106.3°C, and in the glass transition as well as rubbery regions, it was observed to compete with the E′ value of the control GE composites. Fractography was done using micrographs obtained from environmental scanning electron microscope (ESEM). Traces of polymeric material found at the fiber surface certified the improved interfacial adhesion between glass fiber and polymer in the matrix‐modified composite samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chitosan (CS) and tripolyphosphate (TPP) can be combined in the development of a material with synergistic properties and promising potential for the conservation of food products. In this study, ellagic acid (EA) and anti‐inflammatory peptide (FPL)‐loaded CS nanoparticles (FPL/EA NPs) were prepared using the ionic gelation method and optimal preparation conditions were obtained through a single factor design. RESULTS: The synthesized nanoparticles (NPs) were characterized using a scanning electron microscope (SEM), Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and differential scanning calorimetry (DSC). Nanoparticles were spherical, with an average size of 308.33 ± 4.61 nm, a polydispersity index (PDI) of 0.254, a zeta potential of +31.7 ± 0.08 mV, and a high encapsulation capacity (22.16 ± 0.79%). An in vitro release study showed that EA/FPL had a sustainable release from FPL/EA NPs. The stability of the FPL/EA NPs was evaluated for 90 days at 0, 25, and 37 °C. Significant anti‐inflammatory activity of FPL/EA NPs was verified by nitric oxide (NO) and tumor necrosis factor‐α (TNF‐α) reduction. CONCLUSION: These characteristics support the use of CS nanoparticles to encapsulate EA and FPL and improve their bioactivity in food products. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This study investigated the friction and wear properties of high‐strength polyacrylonitrile (HS‐PAN)‐, high‐modulus polyacrylonitrile (HM‐PAN)‐, and high‐modulus pitch (HM‐pitch)‐based carbon fiber‐reinforced polymer matrix composites (CFRPs) with silicon carbide (SiC) nanoparticles. The fiber orientation of the CFRP specimens was set as 8‐ply unidirectional laminates, denoted as [0]8. Ball‐on‐disk (cyclic) wear testing was accompanied by laser, digital, and scanning electron microscope observations. For the HS‐PAN CFRP, the coefficient of friction and wear resistance were the highest among the HM‐PAN and HM‐pitch CFRPs and wear resistance was improved by the addition of SiC‐nanoparticles. Furthermore, there was no significant enhancement of wear resistance for the SiC‐nanoparticle‐filled and nanoparticle‐unfilled HM‐PAN CFRP. The wear resistance was improved by adding SiC‐nanoparticles for the HM‐pitch CFRP. [ABSTRACT FROM AUTHOR]

Since the development of bacterial resistance towards antibiotics has the potential to limit the effectiveness of antibiotics in the treatment of infectious diseases, it is necessary to try different strategies to provide alternatives. In order to solve the problems, this work used silver nanoparticles‐loaded polydopamine‐modified montmorillonite (AgNP/PDA−Mt) to cope with the infection of the gram‐negative bacteria Escherichia. Coli and the gram‐positive bacteria Staphylococcus. aureus. Polydopamine‐modified montmorillonite (PDA−Mt) was used to reduce silver ions into silver nanoparticles through the hydroxyl groups of polydopamine. The chemical properties and morphology of AgNP/PDA−Mt were analyzed by X‐ray diffraction spectroscopy (XRD), fourier transform infrared spectroscopy (FT‐IR), transmission electron microscope (TEM), scanning electron microscope (SEM), etc. Also, its antimicrobial property has been investigated. The results showed that AgNP/PDA−Mt possessed significant sterilization at low doses. And the results had been shown its acceptable biocompatibility. [ABSTRACT FROM AUTHOR]

Silver nanoparticles functionalized poly‐p‐phenylene terephthamide (PPTA) fiber was fabricated through the electroless plating method. To facilitate the efficient deposition of silver nanoparticles, the PPTA fiber surface was modified by using dopamine and γ‐methacryloxypropyl trimethoxy silane (MPTES). Various techniques including scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS) and X‐ray diffraction (XRD) were used to characterize the surface morphology and chemical composition of surface modified and silver‐plated PPTA fibers. The silver‐plated PPTA fiber showed a surface resistance of 0.53 Ω over a length of 1 cm with reliable coating fastness under ultrasonic washing and high temperature treatment. Furthermore, the silver‐plated PPTA fiber exhibited antibacterial resistance against Escherichia coli and Staphylococcus aureus, as well as good electrical heating performance with surface temperature of 100.4°C at a voltage of 4.5 V. [ABSTRACT FROM AUTHOR]

Sulfonic acid functionalized silica coated cobalt ferrite nanoparticles (CoFe2O4/SiO2−SO3H) was prepared as an efficient solid acid catalyst for the green synthesis of dihydropyrimido[4,5‐b]quinolinetrione derivatives. CoFe2O4 NPs were prepared by co‐precipitation method and then the silica‐coated CoFe2O4 NPs were modified with chlorosulfonic acid. Obtained CoFe2O4/SiO2−SO3H was characterized by thermo gravimetric analysis (TGA), Fourier transform‐infrared spectroscopy (FT‐IR), scanning electron microscope (SEM), energy‐dispersive X‐ray spectroscopy (EDX), X‐ray diffraction (XRD) and vibrating‐sample magnetometer (VSM). The magnetically separable CoFe2O4/SiO2−SO3H was successfully used for the four component reaction of barbituric acid, dimedone, amines (or ammonium acetate) and benzaldehyde derivatives for the synthesis of dihydropyrimido[4,5‐b]quinolinetriones under thermal and ultrasound conditions. The advantages of presented simple protocol are the easily separation of magnetic catalyst from the reaction medium by an external magnet, short reaction times, green reaction conditions in addition to simple workup and high yield of products. [ABSTRACT FROM AUTHOR]

In this study, the effect of sonication time on the mechanical properties of graphene nanoplatelets (GnPs) glass fiber composites were discussed. The Sonication process is one of the best techniques to ensure uniform dispersion of nanofillers into the polymer matrix; otherwise, they form agglomerates of multilayers. To fulfill the massive demand for mass production, ultrasonic bath‐type sonication were deployed. In this study, 0, 1, 2, 3, 4, and 5 wt% of GnPs were added with epoxy at different sonication durations, precisely 0, 20, 40, and 60 min. Other sonication process parameters were kept constant with a sonication frequency of 28 KHz. Bidirectional glass fabric materials was used as reinforcement material in the fabrication of the laminates. In total, 21 laminates were fabricated using the hand lay‐up technique in various amalgamations. The tensile and flexural specimens were cut from the laminates as per the standards to determine their mechanical properties. The scanning electron microscope (SEM) images were used for the structural analysis of the glass fiber reinforced GnPs/epoxy composite. Surface morphology of GnPs becomes more wrinkled, resulting in a stronger graphene/epoxy matrix interface, enhancing the tensile strength and tensile modulus performance of the nano‐composites increases up to 37.12% and 66.30%, the flexural strength and flexural modulus performance of the nano‐composites increases up to 55.74% and 91.23% respectively. Based on the investigations, the influence of the GnPs percentage and the sonication duration for the preparation of the nano‐composites with the help of technique for order of preference by similarity to ideal solution (TOPSIS) optimization technique. [ABSTRACT FROM AUTHOR]

Carbon‐phenolic ablators are very efficient heat shields for atmospheric reentry vehicles: they are able to protect a capsule from hyper thermal environments characterized by intense heat fluxes (>1 MW/m2) and very high temperature (also exceeding 300°C). Ablative materials can be modified by the addition of nano‐fillers in order to improve their performance: small amounts of nano‐fillers (in the order of 2–5 wt%) are able to enhance the matrix material properties, guarantying a weight saving too. In this work, three different kinds of ceramic nano‐particles (ZrO2, SiC, and MgO) were tested as fillers for a phenolic resin and for a carbon‐phenolic ablator: the variation in the mechanical properties and ablative performances were verified through mechanical tests and oxyacetylene flame exposure. The influence of the nano‐particles in the composite materials properties and the phenomena connected to their presence in the ablative material were deeply investigated with scanning electron microscope, EDS, XRD, and FTIR analysis. [ABSTRACT FROM AUTHOR]

Niobium pentoxide (Nb2O5) is a promising heterogeneous acid catalyst because of its water‐tolerant acidity. However, the reactivity of Nb2O5 is limited to the surface of a bulk material; thus, its catalytic activity is generally lower than homogeneous catalysts. Nano‐sized Nb2O5 shows superior activity but has low stability and recoverability. We develop spiky‐shaped Nb2O5 composed of radially grown nanorods, which show high stability but low acidity. In this study, an Al‐doping method and the doping effect on the acidity and nanostructure of the spiky‐shaped Nb2O5 are demonstrated. Al of 1–6 mol% is doped in Nb2O5 while maintaining the spiky nanostructure using an Nb–Al composite oxalate as a precursor. Scanning transmission electron microscope analysis results show that the doped Al ions are homogeneously dispersed in the structure. Al doping increases the catalytic activity, where 4 mol% Al‐doped Nb2O5 shows the highest production rate of 2‐phenyl‐2‐phenylaminoacetonitrile in a Strecker reaction. From the acid analysis and Raman spectroscopy, it can be concluded that the Al doping is effective in adjusting acidity and in enhancement of catalytic activity due to creation of NbO4 and distorted NbO6. These are produced by defect formation and lattice distortion caused by differences in valence and ionic radius between Al and Nb. [ABSTRACT FROM AUTHOR]

Boron nitride nanoplatelets (BNNPs) are emerging as a potential candidate for developing polymer‐based thermally conducting nanocomposites that have electrically insulating properties. Generally, the mechanical performance of such polymer‐based nanocomposites, for example, toughness, is often found to be inferior, primarily, owing to the poor dispersion of BNNP, resulting from weaker interfacial interactions between BNNPs and polymer matrices. Here, we report on a successful method to fabricate high density polyethylene (HDPE)/BNNP nanocomposites, with superior mechanical properties, through the in situ exfoliation of the nanofiller via a melt‐extrusion technique. The results obtained showed that the toughness of a nanocomposite with 15 wt% BNNP loading is 18.8 × 103 KJ m−3, that is, about 1.5 times enhancement as compared to the control HDPE sample. The enhancement in mechanical properties can be attributed to a greater degree of homogeneous dispersion of the exfoliated BNNPs achieved using the melt‐ extrusion route. The results that were analyzed through scanning electron microscope and Fourier transform infrared measurements showed that an interesting microstructural feature, named "sunflower‐like" core‐shell structure, formed owing to the relatively stronger interactions between BNNPs and polyethylene chains, which in turn facilitated the uniform dispersion of exfoliated BNNPs in HDPE matrix. This work, therefore, opens up a pathway toward an easy and up‐scalable version for fabricating polymer nanocomposites that have superior mechanical performance and with wider applicability. [ABSTRACT FROM AUTHOR]

Nanometer molecularly imprinted polymers (nano‐MIPs) spherical particles with specific recognition of sialic acid (SA) are synthesized by electrochemically mediated atomic transfer radical polymerization combined with the precipitation method. SA is used as template molecules,4‐vinylphenylboronicacid as functional monomer, and ethylene glycol dimethacrylate as the crosslinking agent. The successful synthesis of spherical nano‐MIPs is verified by Fourier transform infrared spectroscopy, scanning electron microscope, and Malvern particle size instruments. The effects of the potential adjustment on the morphology, size, and particle size distribution of MIP particles are further investigated. By adjusting the potential for polymerization, nanoparticles with average sizes of 160.32, 275.87, and 331.99 nm are obtained. The recognition performance of nano‐MIPs for SA is characterized by a UV–vis spectrophotometer and the satisfactory imprinting factor is 1.54. [ABSTRACT FROM AUTHOR]

This study aimed to produce and characterize the microstructure and mechanical properties of dense polycrystalline bovine hydroxyapatite (DPBHA) bioceramics with 5% and 8% of TiO2 nanoparticles after final synthetization for future use in dental implants. Structural characterization was obtained from analyzes by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscope, energy dispersive spectroscopy, and relative density and apparent porosity. The mechanical characterization was performed by measuring the fracture toughness after three‐point flexural strength (FS) test. The microstructural characterization results showed no secondary phase formation and nonhomogeneous nanoparticle dispersion in HA matrix. DPBHA/Np8% (2.9 ± 0.09 g/cm3) exhibited significantly greater density than DPBHA (2.7 ± 0.03 g/cm3) (p = 0.011) and DPBHA/Np5% (2.7 ± 0.05 g/cm3) (p = 0.041). DPBHA (0.9%) had the smallest porosity followed by DPBHA/Np8% (3.4%). DPBHA/Np5% (4.5%) exhibited the greatest proportion of pores. Pure HA (51.7 ± 10.3 MPa) and DPBHA/Np8% (47.4 ± 6.4 MPa) had significant greater FS (p < 0.001) than DPBHA/Np5% (28.8 ± 3.1 MPa). DPBHA (0.43 ± 0.01 MPa m1/2) and DPBHA/Np8% (0.40 ± 0.06 MPa m1/2) presented greater KIc than DPBHA/Np5% (0.23 ± 0.02 MPa m1/2) (p < 0.003; p < 0.007). In conclusion, 8% TiO2 nanoparticle addition to this synthesis would be a promising HA blend, as mechanical properties were similar, and the relative density/apparent porosity showed superior results than those of the DPBHA. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of aluminum nitride (AlN) on the self‐cleaning and bouncing properties of room temperature vulcanized (RTV) silicone rubber, a superhydrophobic AlN/RTV composite with micro‐nano structure was prepared by powder scattering technology. The method combines the characteristics of RTV curing at room temperature, and has the advantages of simple operation, low cost and easy realization. Bouncing experiments, with different droplet sizes, different tilting angles and different temperatures, and self‐cleaning experiments were designed. The micro‐morphology of superhydrophobic surface was analyzed by Raman spectroscopy, scanning electron microscope, energy dispersive spectrometer, and interferometric 3D profilometer. The results show that the static contact angle and the rolling angle of AlN/RTV are 157.7 ± 0. 9° and 4.2 ± 0.7°, respectively. Many micro‐roughness structures were formed on the RTV surface by AlN, which reduced the contact area between droplets and the sample surface, so the samples had outstanding self‐cleaning and bouncing properties. [ABSTRACT FROM AUTHOR]

Herein, a new strategy for improving epoxy coatings' anti‐corrosion performance has been developed, which combined NH2‐Ce‐MOF with graphene oxide (GO) by hydrothermal method. First, the nanocomposite material's morphology and structure (GO‐Ce‐MOF) were confirmed by Fourier transform infrared, X‐ray diffraction, TG, X‐ray photoelectron spectroscopy, and scanning electron microscope (SEM) studies. The dispersity of the composite in the epoxy coating was evaluated by SEM and mapping analysis. Meanwhile, the anti‐corrosion of as‐prepared composite coatings was investigated in detail by the electrochemical impedance spectroscopy (EIS) and the Tafel polarization curve test. The results illustrated that 2.0 wt% GO‐Ce‐MOF/EP greatly enhanced the composite coating's anti‐corrosion performance compared to other coatings. The reasons for the improvement of the anti‐corrosion performance of the composite coating are attributed to the following two aspects: On the one hand, the addition of GO can provide a physical barrier to form a labyrinth effect to slow down the invasion of corrosive media into the metal substrate, on the other hand, the modification of GO can GO‐Ce‐MOF achieve better compatibility and dispersion in epoxy resin. [ABSTRACT FROM AUTHOR]

By looking at its wide range of applications, the aim of this study is the preparation and characterization of potassium chloride (KCl) nanoparticles by green synthesis using Curcuma longa plant. The detail characterization of KCl nanoparticles is carried out using X‐ray diffraction (XRD) analysis, UV–Visible spectroscopy, and scanning electron microscope (SEM) analysis that the result of KCl nanoparticles is observed as spiny, rock, semispherical, and spherical shape. The results of antibacterial activity show the inhibitory activity against bacteria in the case of preparing KCl by the method of plants, the results are noted that the best concentration in the inhibition area is (31 mm) in bacteria (Staphylococcus epidermidis) at a concentration of (100% mg mL−1). [ABSTRACT FROM AUTHOR]

Nanoparticles have been widely used in the improvement of the mechanical and thermal properties of the epoxy matrix. In this study, the room temperature curing agent composed of acrylic acid and 2,4,6‐trimethyl‐m‐phenylenediamine was mixed with different concentrations of CeO2 nanoparticles into the epoxy resin (E51) to obtain a nanocomposite that can be rapidly molded and cured. Fourier transform infrared spectroscopy and differential scanning calorimetry were used to study the curing behavior of nanocomposites and E51 with the synthesized hardener. Through tensile, flexural, and impact tests, the influence of the nanoparticles content on the mechanical and thermal properties of the prepared composites was discussed. The results showed that the curing process was completed in 4 h. An increase of 78.4% in tensile strength, 81.7% in flexural strength, and 122.0% in elongation were obtained for the cured nanocomposite having 5 wt% CeO2 loading compared to the neat resin. Thermogravimetric analysis result showed that the thermal stability increased with increasing of CeO2 nanofillers content. Finally, the scanning electron microscope revealed the fracture surface morphology of the composites. [ABSTRACT FROM AUTHOR]

The structural and optical properties of pristine and photoactivated surfaces of facet [001] of 2D BiOI nanoplatelet powders synthesized with an antisolvent method were studied using X‐ray diffraction (XRD), a scanning electron microscope, X‐ray photoelectron spectra (XPS), visible–near infrared (vis–NIR) absorption, and transient absorption spectroscopic techniques. The synthesized BiOI nanoplatelets possessed a tetragonal structure with length 200–400 nm and thickness less than 50 nm. XRD analysis showed that the photoactivation did not affect the crystal structure. In contrast, the XPS analysis showed vacancies associated with elements Bi, I, and O. The band gaps estimated from the diffuse reflectance spectra of pristine and photoactivated samples are 1.83 and 1.80 eV, respectively. Femtosecond transient‐absorption spectra measured in the vis–NIR (2.25–0.9 eV) region showed photobleach bands associated with the band edge, shallow trap, and deep trap states. A global fit of the transient spectral profiles showed that all bands decay synchronously for both pristine and photoactivated samples, but the photoactivated samples showed a greater magnitude of carrier‐carrier annihilation following photoexcitation due to photodoping caused by defects. A carrier‐relaxation model involving thermal equilibrium between band‐edge, shallow, and deep trap states is proposed to explain the synchronous decay of all bands. [ABSTRACT FROM AUTHOR]

This study is aimed to synthesize zinc oxide nanoparticles (ZnO NPs) from Aloe barbadensis Miller leaf extract using the green synthesis method at room temperature. The biosynthesized NPs are characterized by X‐ray diffraction (XRD), UV–vis spectroscopy (UV–vis), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscope (SEM). The XRD pattern has revealed the hexagonal wurtzite structure with a crystallite size of 16 nm for synthesized ZnO NPs. The FTIR results display the formation of ZnO NPs and the presence of other functional groups. The UV–vis absorption spectrum shows an absorption band at 347 nm and the value of the bandgap is found to be 3.75 eV. The surface morphology of synthesized NPs is visualized by SEM images, it is observed that most of the NPs are needle in shape. Further, these NPs will find applications in biosensing and photocatalytic activity. [ABSTRACT FROM AUTHOR]

The aim of this research is to investigate the thickness influence on the efficiency of multiwalled carbon nanotubes (MWCNTs) in glass/epoxy composite laminates under the high‐velocity impact. Combining 0.25 wt% of MWCNTs in the 4‐layer and 8‐layer specimens and 0.1 wt% of MWCNTs in the 16‐layer specimen led to the maximum rise in the energy absorption and specific perforation energy compared with the unreinforced laminates. The significant growth in energy absorption in the 4‐layer, 8‐layer, and 16‐layer specimens was 5.8, 8.3, and 14.4 J, respectively. The number of agglomerations (dislocations) in the matrix was consequently increased as a function of thickness, which led to the better performance of MWCNTs with lower weight percentages in the composite laminates containing more layers. The scanning electron microscope was used to observe the dispersion and agglomeration of MWCNTs in the resin epoxy, and there was also an improvement in the fiber–resin bonding. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HAp) nanoparticles stabilized Pickering emulsions were prepared by dichloromethane (CH2Cl2) dissolved poly(L‐lactic acid) (PLLA) as the oil phase and the deionized water with different concentrations of cetyltrimethyl‐ammonium bromide (CTAB) as the aqueous phase. Effect of CTAB concentration on emulsions type and stability were studied. The emulsion type underwent a two‐phase inversion, and emulsion stability increased first and then decreased with increasing CTAB concentrations. Besides, effect of CTAB concentration on zeta potential, aggregate size, contact angle of HAp nanoparticles and the oil–water interfacial tension were studied. The results indicated that zeta potential value of HAp nanoparticles changed from negative to positive, and the contact angle increased to over 80° initially and then decreased to below 40° rapidly. The distribution of HAp nanoparticles on the surface of emulsion droplets with different concentrations of CTAB (5 and 20 mM) was characterized using laser‐induced confocal microscope. It revealed the distribution of HAp nanoparticles changed with different CTAB concentrations. The cured PLLA materials were obtained after the solvent being volatilized using as‐received emulsions as templates. Scanning electron microscope images showed both microspheres and porous materials with interconnected pore structure were obtained. In conclusion, the microstructure of microspheres or porous PLLA materials is controllable by adjusting the property of HAp nanoparticles stabilized Pickering emulsions with appropriate amount of CTAB. [ABSTRACT FROM AUTHOR]

Curcumin nanoparticles were most recently considered in medical research because of their antibacterial properties. The main objective of the study was to develop the green synthesis and antibacterial activity of curcumin nanoparticles using Curcuma longa. The processing of curcumin nanoparticles was carried out after the collection, identification, and extraction of curcumin. The effect of a sample on the synthesis of nanoparticles, such as curcumin aqueous concentrations (5, 10, and 20 mg/ml) and curcumin nanoparticles (5, 10, and 20 mg/ml), and the antibacterial effect of these nanoparticles on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and the fungal strain Aspergillus niger. For examining antibacterial and anti‐fungal activity disc diffusion method was performed, followed by the zone of inhibition. According to X‐ray diffraction and scanning electron microscope analysis, nanoparticles have spherical shapes and size of 42.64 nm. Results showed that a high dose of 20 mg/ml curcumin nanoparticles have more antibacterial activity than curcumin extracts in E. coli as it showed the largest diameter of zone of inhibition as compared to other doses. Other bacterial and fungal strains also showed significant results but E. coli was most prominent. The biosynthesis of curcumin nanoparticles using an aqueous extract of C. longa is a clean, inexpensive, and safe method that has not been used any toxic substance and consequently does not have side effects. Since several pathogenic species have acquired antibiotic resistance, the combination of curcumin with various nanoparticles would be beneficial in the cure of pathogenic diseases. [ABSTRACT FROM AUTHOR]

The rise in demand for energy and pollution of the environment from the usage of petroleum products promote research to explore environmentally friendly substitutes. Brucea Javanica oil has the potential to be a mineral oil and is plentiful and cheap in India. In this research work, the oil was epoxidized to focus on improving the oxidation stability of the Brucea Javanica oil. In addition, ZrO2 nanoparticles are introduced to the chemically modified Brucea Javanica oil in a particular proportion and tested for tribological behavior. The epoxidation process provided better lubricating properties due to an increase in viscosity, flash point, and pour point. During the assessment, 0.5% consisting of ZrO2 nanoparticles resulted in significant reductions in coefficient of friction and rate of wear. Worn surfaces were analyzed using scanning electron microscope and they exhibit excellent surfaces when nanoparticles were introduced up to 0.5% concentration due to improved lubricant film formation on metal surfaces. The optimal level of inclusion to the epoxidized Brucea Javanica oil was discovered at a concentration of 0.5%, and an increase after this limit results in maximum wear of the surfaces due to their agglomeration on the surface. So, nanoparticles up to a certain limit are useful for reducing the friction and wear of the surfaces. [ABSTRACT FROM AUTHOR]

ZnO/ZrO2 samples were obtained by impregnation ZnO on three different ZrO2 polymorphic phases: monoclinic, tetrahedral and amorphous. The catalysts were tested for CO2 hydrogenation to methanol and the structure was determined using nitrogen physisorption, scanning electron microscope (SEM), Fourier transform infrared (FT‐IR) pyridine adsorption, hydrogen temperature‐programmed desorption (H2‐TPD), CO2‐TPD and X‐ray photoelectron spectroscopy (XPS). The results showed that the ZnO/tm‐ZrO2‐500 catalyst, with a mixture of both tetrahedral and monoclinic ZrO2 phases, had the highest CH3OH yield among all the samples. The yield of methanol is correlated to the lattice oxygen content for all the catalysts. During the reaction, formate and methoxy species seemed to be the active intermediate species. [ABSTRACT FROM AUTHOR]

Hypochlorous acid (HOCl) plays a crucial role in many physiological processes and is widely used as bleach, deodorant and fungicide. In this work, we designed an amphiphilic hydrazone fluorescent molecule THG‐1 containing hydrophilic sugar units and hydrophobic tetraphenylethylene unit for ratiometric detection of HOCl with high sensitivity and excellent selectivity based on HOCl‐triggered hydrolyzation reaction and aggregation‐induced emission (AIE) effect. The detection mechanism was verified by liquid chromatograph mass spectrometry experiments and scanning electron microscope (SEM) tests. Contrast experiments revealed that the numbers of lactose unit and hydrazone linker were essential for assembly of THG‐1 and detection of HOCl. In addition, THG‐1 was successfully used for imaging of exogenous and endogenous HOCl in living cells. [ABSTRACT FROM AUTHOR]

MoS2 can generate useful molybdenum oxides by thermally reacting with LiF or Ag nanoparticles (NPs). MoS2 easily loses sulfide and reacts with oxygen gas upon heating in air to give orthorhombic molybdenum trioxide, α‐MoO3. Morphological changes of α‐MoO3 from 500 to 900°C were investigated using X‐ray powder diffraction and scanning electron microscope. The strong diffraction peaks of the (020), (040), and (060) planes at 800°C revealed highly anisotropic growth of the oxides with a layered crystal structure. In the presence of LiF, MoS2 reacts with oxygen gas to generate Li2MoO4 and MoO2, depending on the LiF concentration. In the presence of Ag NPs, the thermal reactions of MoS2 at 800 and 900°C give silver molybdates Ag2Mo2O7 and Ag2MoO4, respectively. These results demonstrate that MoS2 is an important precursor for generating useful molybdenum oxides on the surface of inert substrates without requiring sophisticated, expensive equipment. [ABSTRACT FROM AUTHOR]

Metal matrix composites with yttria as reinforcement are mostly produced because of it's improved mechanical properties while thermal stability, electrochemical and magnetic properties of the yttria based composites are rarely considered. In the present study, the feasibility of incorporating yttria nanoparticles into nickel matrix from ethylene glycol bath by electro‐codeposition method is demonstrated. The particle content of the coatings was strongly influenced by current density i. e. the rate of metal deposition. Particle content, surface morphology and microstructural changes of the deposits were investigated by scanning electron microscope (SEM) equipped with energy dispersed X‐ray analyzer (EDAX). A dense, compact and smoother composite surface with lower particle content was obtained at higher current densities. Crystallographic structure, texture and lattice strain have been evaluated using X‐ray diffraction (XRD). Incorporation of yttria particles inhibits the grain growth and causes grain refinement of the nickel matrix. Annealed nanocomposite deposits revealed thermal stability up to 700 °C. The comparative electrochemical corrosion behavior of the electrodeposited coatings in 3.5 % NaCl solution and their deposition potential were evaluated. Magnetic studies showed nearly complete absence of hysteresis i. e. soft magnetic nature of the coatings. [ABSTRACT FROM AUTHOR]

In this study, it was aimed to investigate octavinyl‐polyhedral oligomeric silsesquioxane (OV‐POSS) incorporation into natural rubber (NR)/butadiene rubber (BR) elastomer blends as a potential compatibilizer. The effects of OV‐POSS loading levels on the thermal, mechanical, morphological, and dynamic‐mechanical properties of elastomer blends were explored. Fourier‐Transform Infrared Spectrometer (FTIR), Temperature Scanning Stress Relaxation (TSSR), and Differential Scanning Calorimetry (DSC) results revealed the conceivable effect of OV‐POSS nanoparticles in the vulcanization through reacting with sulfur and/or elastomers. Scanning Electron Microscope (SEM), X‐Ray Diffraction (XRD), and tensile test measurements supported the improvement of mechanical properties due to homogeneous dispersion at low loading levels. On the other hand, high amount of OV‐POSS incorporation (7 and 10 phr) resulted in a decrease in mechanical properties, owing to the agglomeration of nanoparticles. According to contact angle and Dynamic mechanical analysis (DMA) results, it could be concluded that OV‐POSS nanoparticles were localized at the interface of the elastomers and enabled the compatibilization of immiscible NR/BR blends. [ABSTRACT FROM AUTHOR]

A useful and green synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones/thiones derivatives were achieved by one‐pot cyclocondensation between substituted aryl aldehydes, diketone/ketoester, and urea/thiourea using magnetic CoNiFe2O4@Silica‐SO3H nanoparticles under solvent‐free condition. The choice of this approach showed essential advantages such as short reaction time, simple work‐up procedure, high activity of the catalyst, high yield of the reaction products, the magnetic properties of the catalyst, and environmentally amiable conditions. In addition, the catalyst recovered and reused four times without notable loss of its activity. The magnetic CoNiFe2O4@Silica‐SO3H nanoparticles were described by Fourier‐transform infrared spectroscopy (FT‐IR), field emission scanning electron microscope, energy dispersive X‐ray spectroscopy, X‐ray diffraction spectroscopy, and vibrating sample magnetometer. The products were obtained with excellent yields (88–98%). The formation of the products was confirmed and identified with their physical properties (melting points), the FT‐IR, 1H NMR, 13C NMR, mass spectrometry, and the elemental analysis. [ABSTRACT FROM AUTHOR]

Nanoparticle size polycrystalline aluminium substituted copper cobalt ferrite samples CuxCo1‐xFe2‐2yAl2yO4 (where x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0; y = 0.05, 0.15, and 0.25) have been prepared by standard ceramic technique. The effects of aluminium and copper on structural properties of cobalt ferrite are studied. A universal testing machine as well as Archimedes' method is applied for determining the physical properties of the samples. Phase formation is investigated using x‐ray diffraction, infrared absorption technique, and scanning electron microscope technique. The size of particle raises with the increase in concentration of Al3+ content. The particle size occurs in the nano range 50–100 nm. The particle size is a very important parameter in terms of ferrite. [ABSTRACT FROM AUTHOR]

Nanozymes exhibit excellent enzyme‐like activities but lack specificity. Here, molecularly imprinted polymers (MIPs) based on polypyrrole (PPy) and using methylene blue (MB) as template were grown on Fe3O4 nanozymes to enhance the catalytic selectivity. The obtained composite Fe3O4@PPy MIPs were characterized using a scanning electron microscope, transmission electron microscope, powder X‐ray diffractometer, and vibrating sample magnetometer. The PPy‐encapsulated Fe3O4 nanozymes retained their catalytic ability and almost completely removed MB within 30 min in the presence of sodium persulfate. In comparison with bare Fe3O4 nanozymes, the Fe3O4@PPy MIPs showed superior catalytic selectivity for MB. The apparent rate constants (kapp) for MB, rhodamine B, and methyl orange were 0.073, 0.035, and 0.012 min−1, respectively. Even after five recycling steps, the obtained Fe3O4@PPy MIPs could degrade more than 80% of MB. [ABSTRACT FROM AUTHOR]

Layered metal/dielectric hyperbolic metamaterials (HMMs) support a wide landscape of plasmon polariton excitations. In addition to surface plasmon polaritons, coupled Bloch‐like gap‐plasmon polaritons with high modal confinement inside the multilayer are supported. Photons can excite only a subset of these polaritonic modes, typically with a limited energy and momentum range in respect to the wide set of high‐K modes supported by hyperbolic dispersion media, and coupling with gratings or local excitation is necessary. Strikingly, electron energy loss spectroscopy (EELS) in a scanning transmission electron microscope allows nm‐scale local excitation and mapping of the spatial field distribution of all the modes supported by a photonic or plasmonic structure, both bright and dark, and also all other inelastic interactions of the beam, including phonons and interband transitions. Herein, experimental evidence of the spatial distribution of plasmon polaritons in multilayered type II HMM nanostructures is acquired with an aloof electron beam adjacent to structures of current interest. HMM pillars are useful for their separation and adjustability of optical scattering and absorption, while HMM slot cavities can be used as waveguides with high field confinement. The nature of the modes is confirmed with corresponding simulations of EEL and optical spectra and near‐field intensities. [ABSTRACT FROM AUTHOR]

In the present study, compatibilization of immiscible blends of polymers was investigated based on the Pickering emulsion concept with various mixing procedures. Silica nanoparticles were incorporated into poly (1,4‐cyclohexanedimethylene isosorbide terephthalate) (PEICT)/isotactic polypropylene (iPP) blends. Localization of nanoparticles was effectively modified by varying mixing procedures. Relocation of hydrophilic silica occurred in a secondary mixing procedure with the PEICT, which has relatively high affinity when primarily mixed with iPP. The final location of the silica nanoparticles was confirmed by SEM images. SEM and an optical microscope were used to follow morphological change. By simply changing the mixing procedure, the hydrophilic silica nanoparticles were able to perform the role of a morphology modifier successfully without modifying the surface characteristics. The mechanical properties and crystallization behavior were also compared depending on the surface characteristics of the silica nanoparticles and their final localization. [ABSTRACT FROM AUTHOR]

Preparation of silver nanoflowers (Ag NFs) was carried out through the self-assembly process of diphenylalanine (FF) peptide on the graphite surface. Pencil graphite rods were used as a substrate for the self-assembly process. A reduction reaction by hydrazine was employed in the synthesis procedure of the Ag NFs. scanning electron microscope, Fourier transform infrared spectroscopy (FT-IR) spectroscopy and X-ray diffraction (XRD) were employed to characterise the obtained Ag NFs. The morphological analysis of the Ag NFs revealed assemblies constructed by multiple sheet nanostructures designed as flower petals and positioned in the form of 3D semi-spherical arrangements. The successful synthesis of Ag NFs was confirmed by FT-IR characteristic bands of FF and Ag components. The cubic lattice structure of the Ag NFs was revealed by XRD. Standard Kirby–Bauer disk diffusion tests using Gram-positive and Gram-negative bacterial strains exhibited the promising antibacterial performance of the Ag NFs against all of the tested bacterial species. [ABSTRACT FROM AUTHOR]

In the present study, the reinforcing effect of aluminum silicon carbide (Al‐SiC) nanoparticles and chemically treated nanocellulose fiber on thermomechanical and corrosion characteristics of polymer nanocomposites have been investigated. The experimental design was selected as per response surface methodology (RSM) to optimize the effect of Al‐SiC (1.59 to 18.41 wt%), nanocellulose fiber concentration (1.59 to 18.41 wt%) and sonication time (39.55 to 140.45 minutes). From the analysis of variance (ANOVA) results, it was found that the Al‐SiC, nanocellulose fiber concentration and sonication time played a significant role in the mechanical properties. In order to simultaneously maximize the flexural strength, the optimal values of nanocellulose fiber, Al‐SiC nanoparticles, and sonication time was found to be 5 wt%, 5 wt%, and 120 minutes, respectively. From the normal distribution plot, it is found that there is a good agreement between experimental results and developed RSM model. Addition of Al‐SiC (5 wt%) and nanocellulose fiber (5 wt%) in epoxy polymer improved the physical, mechanical, thermal and corrosion resistance properties. The scanning electron microscope analysis on Al‐SiC and nanocellulose fiber reinforced epoxy nanocomposites revealed uniform dispersion of nanocellulose fiber and Al‐SiC in the polymer matrix, which caused for the improved mechanical, and corrosion resistance characteristics. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are being recognized as antibacterial agents due to their rapidly increasing multidrug resistance in bacterial pathogens. Hence, there is an unmet need to identify the natural antibacterial agent. The present study aimed to evaluate the antibacterial activity of sericin‐conjugated silver NPs synthesized by using sericin as a reducing and capping agent. Synthesized NPs were characterized by scanning electron microscope, nanolaser particle size analyzer (BT‐90), Fourier‐transform infrared analysis, and energy‐dispersive X‐ray. The biogenic NPs significantly inhibited the growth of Escherichia coli (12–15 mm zone of inhibition), Staphylococcus aureus (14.6–15.4 mm zone of inhibition), and Klebsiella pneumoniae (12.5–18 mm zone of inhibition). The stability of naturally synthesized NPs was examined at various temperatures (i.e., 4°C, 37°C, and 55°C) and pH (i.e., 3, 7, and 11). Temperature variability did not significantly affect the efficacy of NPs. However, NPs performed better at higher pH levels. This study suggested that the sericin‐based silver NPs are not only effective against bacteria, but they also maintain the stability at different ranges of temperature and pH. We concluded that the sericin‐conjugated silver NPs possess the remarkable antibacterial potential, which suggests their large‐scale use as a cheap and stable antimicrobial agent in the future. [ABSTRACT FROM AUTHOR]

Immobilization of enzyme onto nanoparticles such as chitosan can have biotechnological importance. In this study, chitosan nanoparticles (ChNPs) were prepared by Ionic gelation method and Endoglucanase Cel9A from Alicyclobacillus acidocaldariius (AaCel9A) immobilized on the nanoparticles. The FTIR results showed that the enzymes were immobilized on the ChNPs. The dynamic light scattering and scanning electron microscope (SEM) results illustrated that the AaCel9A‐ChNPs approximately had 40 nm diameters. For optimizing enzyme immobilization, response surface methodology was employed using different variables (pH, enzyme immobilization time, and enzyme to ChNPs ratio [E/Cs]). The results showed that the high immobilization efficiency was achieved in pH 7, E/Cs of 0.4 in 2.63 hr. The enzyme activity results showed that, immobilization increased optimum pH for activity (from 6.5 to 7.5) and the enzyme Km (from 3.703 to 12.195 [mg/ml]), which make it suitable to use in some industries such as detergents. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag‐NP‐AE) are synthesized and stabilized by the extract of an ethnomedicine, Albizia lebbeck bark aqueous extract (AE). Ag‐NP‐AE is active against several multidrug‐resistant (MDR) clinical isolates. The nanoparticles are characterized by UV‐vis spectroscopy, Fourier‐transform infrared spectroscopy (FTIR), Dynamic light scattering (DLS), Scanning electron microscope (SEM), Transmission electron microscope (TEM) and X‐ray diffraction (XRD) studies. The antibacterial potency of Ag‐NP‐AE is determined by Disc diffusion, Agar and Broth dilution assays against 14 MDR isolates along with their minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The growth kinetics was determined by quantification of colonies; while toxicity by quantification of viable cells. The Ag‐NP‐AE shows free‐radical scavenging activity at 15–20 μM and is non‐toxic up to 50 μM but demonstrated significant antibacterial activity against all the test isolates with zone diameter of 10.4–19.5 mm and MIC of 0.5–0.84 μM (0.085‐0.143 μg); while the zone diameter with AE was 10.2–15 mm and MIC of 128–1024 μg/mL, respectively; while 100 % killing was observed at 0.50 μM within 2–4 h of exposure due to damage of cellular architectures. [ABSTRACT FROM AUTHOR]