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An innovative polymer-based electro-sensor decorated with Tb nanoparticles has been developed for the first time. The fabricated sensor was utilized for trace determination of favipiravir (FAV), a recently US FDA-approved antiviral drug for the treatment of COVID-19. Different techniques, including ultraviolet-visible spectrophotometry (UV-VIS), cyclic voltammetry (CV), scanning electron microscope (SEM), X-ray Diffraction (XRD) and electrochemical impedance spectroscopy (EIS), were applied for the characterization of the developed electrode TbNPs@ poly m-THB/PGE. Various experimental variables, including pH, potential range, polymer concentration, number of cycles, scan rate and deposition time, were optimized. Moreover, different voltammetric parameters were examined and optimized. The presented SWV method showed linearity over the range of 10–150 × 10−9 M with a good correlation coefficient (R = 0.9994), and the detection limit (LOD) reached 3.1 × 10−9 M. The proposed method was applied for the quantification of FAV in tablet dosage forms and in human plasma without any interference from complex matrices, obtaining good % recovery results (98.58–101.93%). [ABSTRACT FROM AUTHOR]

Sulfidated nanoscale zerovalent iron (S-nZVI) supported on a flower spherical Mg(OH)2 with different Mg/Fe ration were successfully synthesized. The synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET), and X-ray photoelectron spectroscopy (XPS). The results showed that S-nZVI particles were well dispersed on the petals of the flower spherical Mg(OH)2. The influence of factors, including the initial solution pH, Mg/Fe, S/Fe were studied. The trichloroethylene (TCE) adsorption data on Mg(OH)2 and S-nZVI @Mg(OH)2 fit well to a Langmuir isotherm model, and the maximum adsorption of S-nZVI @Mg(OH)2 was 253.55 mg/g, which was 2.6-fold of S-nZVI. Meanwhile, the S-nZVI @Mg(OH)2 composite expanded the pH selection range of S-nZVI from 2 to 11. Cycling experiments showed that removal rate was 58.3% for the 5th cycle. TCE removal was due to synergistic action of reduction coupled with adsorption. During this process, 65.43% of total remove TCE from ion chromatography data was reduced and 34.57% of total remove TCE was adsorbed finally. At the same time, adsorption favors reduction. These observations indicated that the S-nZVI @Mg(OH)2 can be considered as potential adsorbents to remove TCE for environment remediation. [ABSTRACT FROM AUTHOR]

The present work primarily focuses on the thermo-mechanical and physical properties of polymer composites. The effects of normal load, sliding frequency, and temperature on the reciprocating sliding performance of Carbon fiber (CF) segments are evaluated. These CF segments are coated with graphene nanoplatelets (GNPs), and carbon fiber-reinforced polymer (epoxy) composites (CFRPs). Experiments are carried out at three different normal loads (55 N, 75 N, and 95 N), sliding frequency (8 Hz, 12 Hz, and 16 Hz), and temperature (25°C, 40°C, and 60°C). The experiments are conducted for 20 min with a constant stroke length of 1.5 mm against a 62 HRC hardened chrome steel ball as a counter surface material. Optical microscopy and Scanning electron microscope (SEM) have been used to examine the worn surfaces. In addition, an artificial neural network (ANN) is applied to model the coefficient of friction on the basis of different parameters. It has been observed that adding GNPs to carbon fiber strands improves the strand's bonding tendency with the matrix, resulting in an increase in wear resistance. With the addition of GNPs on carbon fiber strands, the specific wear rate decreased by 32.39%, respectively, while the thermal conductivity increased by 47.95%. The coefficient of friction increases with the normal load up to 75 N and then drops. This is due to fiber fragments and friction film at high loads. As the sliding frequency and temperature increase, the friction coefficient gets reduced. It has been found that the ANN model is able to predict the coefficient of friction with high accuracy. [ABSTRACT FROM AUTHOR]

Eu-doped WO3 (WO3:Eu3+) nanoparticles were prepared by the Pechini method. Tetrabutyl titanate (TBOT) was used to prepare TiO2-encapsulated WO3:Eu3+ nanoparticles (TiO2@WO3:Eu3+). Microstructure and morphology of the prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The results show that the mean diameter of the TiO2@WO3: Eu3+ nano powder prepared at pH = 10 is the smallest, up to 50 nm. The tribological properties of the TiO2@WO3:Eu3+ as extreme pressure and wear resistance agents in water-based lubricant were investigated by a four-ball machine. The results showed that TiO2@WO3:Eu3+ exhibits excellent load-carrying capacity, anti-wear, and anti-friction properties in water-based lubricant, especially when the concentration of TiO2@WO3:Eu3+ was 0.4 wt%. The average wear scar diameter (WSD) was decreased from 0.62 to 0.34 mm and the coefficient of friction (COF) was reduced from 0.0721 to 0.053. This is mainly because of the formation of tens of nanometers thick tribofilm, the actual contact between metals is prevented. [ABSTRACT FROM AUTHOR]

In modern chemistry, great interest has been paid to introducing outstanding photocatalysts for degrading organic pollutants. Herein, a highly efficient binary AgI/Ag2WO4 photocatalyst was prepared from AgI and Ag2WO4 nanoparticles (NPs) and characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), electrochemical impedance spectroscopy (EIS), and Fourier transform infrared (FT-IR) techniques. In the Scherrer model, the average crystallite sizes of 34.9, 42.0, and 24.1 nm were estimated for the AgI, Ag2WO4, and the binary catalyst, while the values were 91, 13, and 85 nm by the Williamson-Hall model. FTIR confirmed the presence of W–O–W, O–W–O, Ag-I, and O–Ag–O bonds in the coupled material. DRS results showed absorption edge wavelengths of 451, 462, and 495 nm (corresponding to the band gap values of 2.75, 2.68, and 2.51 eV) for Ag2WO4, AgI, and AgI/Ag2WO4 catalyst, respectively. Synergistic photocatalytic activity of the coupled system was achieved towards ceftriaxone (CTX) in an aqueous solution (about 33% 10 ppm CTX solution was degraded without any optimization in the initial conditions of catal dose 0.3 g/L (Ag2WO4:AgI with mole ratio 1:2 and 30 min abrasion time), and irrad. time 45 min, CCTX). This boosted effect depended on the AgI:Ag2WO4 mole ratio and grinding time for the mechanical preparation of the binary catalyst (optimums: mole ratio of 4:1 and time 30 min). The photodegradation kinetics obeyed the Hinshelwood model with the apparent first-order rate constant (k) of 0.013 min−1 (t1/2 = 53.30 min). Performing the COD on the photodegraded CTX solutions got a Hinshelwood plot with a slope of 0.019 min−1 (t1/2 = 36.5 min). [ABSTRACT FROM AUTHOR]

The steam channeling channel formed during steam huff and puff can be blocked by temperature-resistant gel to improve the steam stimulation effect. In this study, a terpolymer prepared by the polymerization of acrylamide, N-Vinyl-pyrrolidone, and 2-acrylamide-2-methypropanesulfonic acid was selected as gelatinizer, hydroquinone, and hexamethylene tetramine were used as cross-linking agents to prepare gel. The stabilization time of the gel at 175 °C was dramatically extended from 3 days to more than 50 days by adding nanoparticles. The gel prepared with 0.6 wt% polymer, 0.1 wt% hydroquinone, 0.1 wt% hexamethylene tetramine, and 0.9 wt% silica nanoparticles can exist stably for 70 days at 175 °C, which provided a potential choice for plugging the steam channeling channel. The rheological experiments showed that the addition of nanoparticles increased the elastic tendency of the polymer solution to improve the structural strength of the heterogeneous network chain. Dynamic light scattering experiments showed that nanoparticles contribute to the dispersion of polymers in water. The micrographs of the gel were observed by scanning electron microscope, verified that the addition of silica nanoparticles strengthened the gel grid structure and increased the gel grid density, which might be one of the main factors to improve the thermal stability of gels. [ABSTRACT FROM AUTHOR]

Present work reports the newly synthesized resin polymethylene, bis-2-methoxy-1-napthaldehy-o-phenylenediimine (PMBMNOPhen) and then react with titanium dioxide and silicon dioxide to form encapsulated resin by metal oxide nanoparticles (PMBMNOPhenTiO2/SiO2) and resulted in the material is polymethylene, bis-2-methoxy-1-napthaldehy-o-phenylenediimine titanium-dioxide nanoparticles (PMBMNOPhenTiO2). The resin-encapsulated metal oxide nanoparticles were successfully identified morphology, crystal structure, and light absorption capacity of samples were characterized via scanning electron microscope (SEM), X-ray diffraction, energy dispersive (EDS) X-ray diffraction analysis (XRD) and ultraviolet–visible spectroscopy methods. Afterwards, the resin-encapsulated metaloxide nanoparticles are used for degradation of methylene orange (MO) dye. The photo-oxidation rate of the dye is dependent on the different parameters: initial dye concentration, effect of time, the effect of NaBH4 and effect of dose of catalyst. The degradation of MO 60–80%% in real water samples with respect time of 30–60 minutes. These results confirm the prepared resin-encapsulated titanium dioxide nanoparticles (PMBMNOPhenTiO2/SiO2) displaying a great photocatalytic activity for the degradation of methylene orange dye under visible light irradiation effect of a catalyst in real water sample degradation. The synthesized catalyst (PMBMNOPhenTiO2/SiO2) was successfully applied in real dye water solution (colored water), collected from Jamshoro, Sindh (Pakistan). The resin-encapsulated metal oxide nanoparticles showed an excellent performance to reduce MO dye in contaminated water. These results approve that the resin-encapsulated titanium dioxide nanoparticles (PMBMNOPhenTiO2) display a great photocatalytic activity for the degradation of MO dye under visible light irradiation degradation. Photocatalytic degradation using resin-encapsulated (TiO2/SiO2) catalyst is effectively used for the textile dye (MO). [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]

The aim was to prepare experimental adhesive (EA) with ZrO2 nanoparticles (ZEA) and without it; and its interaction with dentin conditioned with photodynamic therapy (PDT), etch and rinse, and Er, Cr: YSGG laser (ECL). Methods consisted of the scanning electron microscope (SEM), energy dispersive X-ray (EDX), shear bond strength (SBS) failure mode, and rheological property analysis. The methods were employed to assess bond integrity; the shape of ZrO2 NPs and interfacial dentin and adhesive interaction. Ninety premolar teeth were collected and pre-bonding, conditioning of dentin was performed utilizing phosphoric acid (H3PO4), photodynamic therapy (PDT), and ER-CR-YSGG laser (ECL). The teeth were set to form bonded specimens using two adhesives EA and ZEA. The microscopic imagery of ZrO2 revealed irregular-shaped, non-edged particles. EDX analysis revealed Zr to be 75.7% whereas, O2 by weight was 25.3%. The highest SBS was demonstrated in dentin conditioned with etch and rinse and ZEA (19.05 ± 0.13 MPa). Whereas, the lowest SBS was observed in dentin surface treated with PDT and EA (12.25 ± 0.14 MPa). Most of the reported failure modes were adhesive. Rheological analysis revealed that with increasing frequencies the viscosities of adhesives were reduced. The presence of 10% ZrO by weight in adhesive improves SBS of restoration and this improvement in bond values is statistically significant compared to EA. Bond values may be influenced by surface treatment of dentin. [ABSTRACT FROM AUTHOR]

This study proposed a two-step method involving hydrothermal and electrostatic self-assembly processes for synthesising an amine-functionalised magnetic ligand graphene oxide–based nanocomposite (EDTA@Fe3O4@GO). The amine groups were successfully attached to the surface of iron (II, III) oxide (Fe3O4), which were embedded on the surface of graphene oxide (GO) (Fe3O4@GO). This EDTA@ Fe3O4@GO nanocomposite was used as a chelating agent to bind the toxic heavy metal ions. EDTA@Fe3O4@GO demonstrated the synergistic effect between the large surface area and magnetic behaviour of Fe3O4@GO and the chelating effect of EDTA, and it showed higher efficiency than the individual GO and Fe3O4. The possible structural and compositional characteristics were proposed based on Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET) and Raman spectroscopy analysis. The outcomes revealed the mechanism behind the excellent As(V) adsorption onto EDTA@Fe3O4@GO. The adsorption process was studied by fitting the experimental data obtained into various kinetic and isotherm models. The pseudo-second-order (PSO) kinetic model and the Freundlich isotherm model (FIM) were found to be the best fit models for the removal of As(V) by EDTA@Fe3O4@GO. EDTA@Fe3O4@GO has the utmost adsorption capacity of 178.4 mg/g. Furthermore, the EDTA@Fe3O4@GO nanocomposite is reusable, and it showed excellent adsorption capacity up to 5 cycles. This study has provided insight into the potential of EDTA@Fe3O4@GO and its applications in large-scale wastewater treatment. [ABSTRACT FROM AUTHOR]

This work was aimed to assess the antidiabetic effect of orally administered Prosochit®-based nanoparticles of insulin in an animal model. Five batches of insulin-loaded nanoparticles were prepared as dry water-in-oil-in-water emulsions using different emulsifiers (prosopis gum, Prosochit® 201, Prosochit® 101, Prosochit® 102, and chitosan) for the outer emulsion. Unloaded Prosochit® 101-based nanoparticles were also formulated. The morphology and size distribution of the nanoparticles were studied using a scanning electron microscope and Zetasizer. Forty alloxan-induced diabetic Wistar rats were divided into eight groups. The different groups were administered daily with different formulations (unloaded nanoparticles, the 5 loaded nanoparticles equivalent to 50 IU insulin per kg, purified water, and Actrapid) for 14 days. Blood glucose level was monitored and determined over 24 h. Fasting blood sugar was also taken on days 3, 5, 7, and 14. A graph of the percent blood glucose level relative to time 0 h was plotted against time. The particles showed a water-in-oil-in-water constitution. Both the drug-loaded and the unloaded Prosochit®-based nanoparticles were of nano dimension. There was a significant difference (p < 0.0001) in the antidiabetic effects of all insulin-loaded nanoparticles compared with the negative control. There was no significant difference across the insulin-loaded nanoparticles of prosopis gum, Prosochit® 201, Prosochit® 102, and chitosan while the insulin-loaded Prosochit® 101 nanoparticles showed the best activity, which is comparable to subcutaneous insulin, reducing blood glucose levels to 32.20 ± 3.79%. All the oral Prosochit®-based insulin nanoparticles are characterized by appreciable antidiabetic activity with the activity of Prosochit® 101-based nanoformulation being comparable to that of the subcutaneous insulin. [ABSTRACT FROM AUTHOR]

In this work, AlN nanoparticles were prepared by arc discharge method and transformer oil-based nanofluids containing different concentrations of these nanostructures were prepared and their thermal conductivities and stabilities were investigated at various temperatures. Two aluminum rods were used as the electrodes and nitrogen gas was used as the arc atmosphere. To investigate the factors that influence the size and purity of the nanoparticles, the nitrogen gas pressure and the current flowing through the electrodes were changed. Based on XRD measurements, it was observed that at the pressure of 2 atm. and current of 100 A, the highest purity phase was achieved. Scanning electron microscope (SEM) images indicated that the smallest samples were the ones that were made at a pressure of 3 atm. and arc current of 400 A and had an average particle size of about 67 nm. The band gap of nanoparticles was obtained at 5.6 eV using the Tauc method. Then, transformer oil-based nanofluids with concentrations of 0.5, 1, 2, and 4 wt.% of AlN were prepared and their thermal conductivities and stabilities were investigated. The nanofluid with 4 wt.% of AlN nanoparticles at 60 °C showed a maximum thermal conductivity enhancement of 9.4%. Nanofluids were completely stable for up to a week. [ABSTRACT FROM AUTHOR]

In the present study, binary (Cu9S5 and SnS2) and ternary (Cu2SnS3—CTS) have been prepared by a one-pot thermal decomposition of copper(II) bis (N-methyl-N-paramethoxyphenyl) dithiocarbamate, dimethyltin(IV) bis (N-methyl-N-paramethoxyphenyl) dithiocarbamate, and the co-thermal decomposition of both complexes in oleylamine, respectively. The crystallinity and structural properties of the semiconductor nanoparticles were investigated using X-ray diffraction analyses, which confirmed the purity of the Cu9S5, SnS2, and Cu2SnS3 nanoparticles. Morphological studies using scanning electron microscope (SEM) showed hexagonal plate-like particles of the SnS2, quasi-spherical shapes for both Cu9S5 and Cu2SnS3 in the SEM images. These morphologies were also corroborated by the transmission electron microscopic analysis. Optical analysis by absorption spectroscopy showed absorption in the visible to near infra-red region, and an estimated band gap energy that were greater than their respective bulk. The visible-light photocatalytic evaluation of these nanomaterials showed good activities for the photo-enhanced degradation of methyl orange (MO), with the SnS2 and Cu2SnS3 exhibiting comparable properties (> 90% removal efficiency) and better than the Cu9S5 nanoparticles with < 90% efficiency. The high activity of SnS2 and Cu2SnS3 could be attributed to morphology as well as their structural properties. The method of synthesis showed a facile approach to obtaining these binary and ternary nanomaterials by simple use of precursor compounds, which may also be extended to other metal sulphides. [ABSTRACT FROM AUTHOR]

Nano core–shell drug carriers with high stability, low toxicity, and targeted drug delivery are significance for the delivery of anti-tumor drugs. In this study, Albumin from bovine serum (BSA), serving as a capping agent, was conjugated to MSNs via a cleavable disulfide bond to generate a redox-responsive nanocarrier (MSNs@BSA). Subsequently, cRGD peptide, as a targeting ligand, was modified on the particle surface by a protein cross-linker to obtain nanoparticles with tumor cell-targeting properties (RGD-MSNs@BSA). The construction of RGD-MSNs@BSA was confirmed by DLS analysis, scanning electron microscope (SEM), transmission electron microscopy (TEM), electron dispersive spectroscopy (EDS), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR), respectively. It was displayed that the model anticancer drug doxorubicin (DOX) was efficiently and stably encapsulated in RGD-MSNs@BSA in the absence of glutathione (GSH), and an outbreak of DOX was observed when the particles were exposed to a GSH-containing environment. It demonstrated that disulfide-linked BSA capping can increase the drug loading stability, while enduing it redox sensitivity. Flow cytometry and fluorescence microscope tests displayed that cellular uptake of RGD-MSNs@BSA was much higher than that of particles without cRGD and free DOX. These results indicated that RGD-MSNs@BSA can increase drug tumor-targeting and drug cellular uptake. [ABSTRACT FROM AUTHOR]

Pure and tin-doped magnetite nanoparticles (NPs) were synthesized successfully by co-precipitate method. Scanning electron microscope (SEM) and energy-dispersive X-rays (EDX) specified quantitative evidence for synthesized NPs. The pure and tin-doped magnetite NPs have average particle size of 30 nm and 200 nm, respectively. The magnetite NPs indicate well-defined magnetic behavior and doping of non-magnetic tin decrease its magnetization. The EDX graph indicated doping of Sn+2 ions, whereas XRD results were very effective in structural analysis. The rietveld refinement was helpful for determination of material's structure. The doping of tin in magnetite structure was also specified by FTIR peak at ∼ 546 cm - 1 . The pure and tin-doped magnetite NPs showed almost same antimicrobial behavior against Staphylococcus aureus, whereas tin-doped magnetite NPs showed more antimicrobial behavior against Escherichia coli. These NPs are biocompatible and show effective antimicrobial behavior; therefore, these NPs are potent candidates for biomedical application. These NPs also showed incredible adulticidal behavior against Aedes aegypti, which have been characterized for the first time in the literature. [ABSTRACT FROM AUTHOR]

In this paper, a series of pure-phase Bi2 Fe4 O9 nanocrystals were synthesized by adding different content of FeCl2 in the process of hydrothermal method, and the lower valence iron ions were successfully introduced into Bi2 Fe4 O9. The UVvisible absorption spectrum data proves that the addition of FeCl2 reduces the optical band gap of Bi2 Fe4 O9 from 2.06 eV to 1.96 eV. Both the scanning electron microscope images and X-ray diffraction patterns prove that the synthesized samples are pure-phase square flakes Bi2 Fe4 O9 nanocrystals. Three synthesized Bi2 Fe4 O9 nanocrystal samples (S1, S2, S3, the FeCl2 content of the three samples increased from 0 during the synthesis process, corresponding to x = 0, 0.2 mmol, 0. 4 mmol, respectively) were used for photocatalytic degradation of methyl orange solutions under a 500 W mercury lamp irradiation. It is found that the photocatalytic degradation rate of the three samples is the fastest when 20 µL of hydrogen peroxide is added, and the photocatalytic degradation rate of the S3 sample is faster than that of S1 and S2. In the case of appropriate addition of hydrogen peroxide, the addition of FeCl2 can improve the performance of Bi2 Fe4 O9 in photocatalytic degradation of dye molecules. [ABSTRACT FROM AUTHOR]

In the current world of coatings and nanomaterials, specifically bearings, zinc, chromium, nickel, diamond-like coatings, and molybdenum disulfide are being used, to name but a few. Boron nitride in various forms has been used to enhance the surface properties, such as hardness, wear resistance, and corrosion resistance of dies, tools, etc. In this paper, a significant focus is being given to the improvement of the surface properties of bearing-steel materials by the impregnation of cubic and hexagonal boron nitride nanoparticles. The vacuum heat treatment method is used for treating the sample pins of material equivalents to EN31. In the design of the experiments, the Taguchi method with L27 orthogonal array is used for the optimization of various parameters, such as the weight % of c-BN and h-BN nanoparticles and the temperature of the vacuum treatment. With the help of preliminary experimentation, the three levels of three parameters are decided. The microhardness analysis shows an improvement from 321 HV0.1 to 766 HV0.1 for a 50 µm case depth of nanoparticle impregnation. The evaluation of the influence of selected factors is also performed using ANOVA and the S/N ratio, and it was revealed that hex boron nitride (h-BN) affects the microhardness value more than the other two factors. The friction and wear testing reveal that the wear properties are improved by approximately 1.6 times, and the frictional force also decreases by approx. 1.4 times. Scanning electron microscope (SEM) analysis shows that the nanoparticles are penetrated by 21.09% and 46.99% atomic weight. In addition, a reduction in the friction coefficient and better wear response were achieved as a result of the heat treatment with nanoparticle impregnation. [ABSTRACT FROM AUTHOR]

Contamination of surfaces has long been identified as a significant factor in viral transmission. Therefore, sustained efforts are required to address this issue. This work aims to build a scientific database on nano-sized metal oxides as intelligent materials for surface disinfection against corona viruses, synthesize and characterize nano-sized MgO, and discuss the possibility of using it in virus eradication. The MgO nanoparticle was prepared through the heating method. Meanwhile, XRD diffractometer, Scan electron microscope, and nitrogen adsorption were used to characterize the MgO nanoparticle. The synthesized MgO nanoparticle showed an average crystallite size of 18.55nm, lattice strain 0.0053, surface area 27.56 m2/g and d-spacing 2.1092. The outcomes of this review highlight the advantage and challenges of AgO, CuO, ZnO, TiO2 and MgO nanoparticles and their utilization for surface disinfection against coronaviruses. [ABSTRACT FROM AUTHOR]

Curcumin is a known naturally occurring anti-inflammatory agent derived from turmeric, and it is commonly used as a herbal food supplement. Here, in order to overcome the inherent hydrophobicity of curcumin (Cur), polylactic acid (PLA) nanoparticles (NPs) were synthesised using a solvent evaporation, and an oil-in-water emulsion method used to encapsulate curcumin. Polymeric NPs also offer the ability to control rate of drug release. The newly synthesised NPs were analysed using a scanning electron microscope (SEM), where results show the NPs range from 50 to 250 nm. NPs containing graded amounts of curcumin (0 %, 0.5 %, and 2 %) were added to cultures of NIH3T3 fibroblast cells for cytotoxicity evaluation using the Alamar Blue assay. Then, the curcumin NPs were incorporated into an alginate/gelatin solution, prior to crosslinking using a calcium chloride solution (200 nM). These hydrogels were then characterised with respect to their chemical, mechanical and rheological properties. Following hydrogel optimization, hydrogels loaded with NP containing 2 % curcumin were selected as a candidate as a bioink for three-dimensional (3D) printing. The biological assessment for these bioinks/hydrogels were conducted using THP-1 cells, a human monocytic cell line. Cell viability and immunomodulation were evaluated using lactate dehydrogenase (LHD) and a tumour necrosis factor alpha (TNF-α) enzyme-linked immunosorbent (ELISA) assay, respectively. Results show that the hydrogels were cytocompatible and supressed the production of TNF-α. These bioactive hydrogels are printable, supress immune cell activation and inflammation showing immense potential for the fabrication of tissue engineering constructs. [Display omitted] • Encapsulation of Cur@PLA NPs • Cur@PLA NPs within alginate/gelatin hydrogels modulate anti-inflammatory response of monocytes. • Bioink developed based on Cur@PLA NPs for 3D printable constructs [ABSTRACT FROM AUTHOR]

Zn-doped CuFe2O4 nanoparticles (NPs) were eco-friendly synthesized using plant extract. These nanoparticles were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and thermal gravimetric analysis (TGA). SEM image showed spherical NPs with size range less than 30 nm. In the EDS diagram, the elements of zinc, copper, iron, and oxygen are shown. The cytotoxicity and anticancer properties of Zn-doped CuFe2O4 NPs were evaluated on macrophage normal cells and A549 lung cancer cells. The cytotoxic effects of Zn-doped CuFe2O4 and CuFe2O4 NPs on A549 cancer cell lines were analyzed. The Zn-doped CuFe2O4 and CuFe2O4 NPs demonstrated IC50 values 95.8 and 278.4 µg/mL on A549 cancer cell, respectively. Additionally, Zn-doped CuFe2O4 and CuFe2O4 NPs had IC80 values of 8.31 and 16.1 µg/mL on A549 cancer cell, respectively. Notably, doping Zn on CuFe2O4 NPs displayed better cytotoxic effects on A549 cancer cells compared with the CuFe2O4 NPs alone. Also spinel nanocrystals of Zn-doped CuFe2O4 (~ 13 nm) had a minimum toxicity (CC50 = 136.6 µg/mL) on macrophages J774 Cell Line. [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]

In this paper, inorganic oxide MgO nanoparticles-doped polymer dispersed liquid crystal (PDLC) films were made from a mixture of the prepolymer, SLC1717 liquid crystal, and MgO nanoparticles by the polymerization induced phase separation (PIPS) process. To observe the effect of MgO concentration, PDLC was dispersed with 0.2, 0.4, 0.6, and 0.8 wt.% MgO. Electro-optical properties of the films have been investigated using LCD parameter meter and Scanning Electron Microscope (SEM) at room temperature. It is established that MgO nanoparticles affect the microstructure of PDLC films significantly because of the formed agglomerates of MgO nanoparticles. Results show an improvement in the electro-optical properties and a decrease in the driving voltage for doped systems with MgO nanoparticles. When the doping amount of MgO is 0.8 wt.%, the threshold voltage (Vth) is reduced to about 7.5 V. Therefore, MgO-doped PDLC is expected to become an excellent choice in the field of energy-saving. [ABSTRACT FROM AUTHOR]

This paper focusses on the effect of aluminium oxide nanoparticles concentration on tribological properties of lubricant oil and noise response on Detroit engine 92V friction parts. The nanomaterials were produced by sol-gel production, process. The manufactured nanomaterials and the tested part were evaluated by scanning electron microscope (SEM) analysis. The coefficient of friction (CoF) and noise response were studied. Results analysis illustrated that the addition of Al2O3 nanoparticles has improved the tribological properties of the lubricating oil and decreases the wear rate of engine parts according to the decrease of CoF. Adding 1% wt. of Al2O3 nanoparticles to oil has decreased the wear rate and the CoF more than 0.5% wt. of Al2O3 nanoparticles addition. [ABSTRACT FROM AUTHOR]

Wastewater of industries, which is polluted with different dyes is becoming a severe issue, which should be tackled on priority bases such as to provide an eco-friendly environment. In addition to this, in search of an efficient green synthesized capacitive electrode material, we have synthesized cobalt oxide (Co 3 O 4) nano-materials by employing green chili and sunflower seeds extracts. The as synthesized samples are labeled as Co-P, Co-GC and Co-SF. The successful fabrication of these samples was tested by X-ray diffraction (XRD), scanning electron microscope (SEM), Xray photoelectron spectroscope (XPS). These tests have explored successful fabrication of Co 3 O 4 -based samples comprised on nanoparticles (NPs) in the range of 35–45 nm. Optical properties were studied by UV–vis spectroscope and Co-SF sample has exhibited lowest energy band gap i.e 2.41 eV. Photoluminescence (PL) analysis has explored that Co 3 O 4 NPs prepared by sunflower extracts have offered lowest recombination rate. Among of Co-P, Co-GC and Co-SF photocatalysts, Co-SF has shown excellent photodegradation activity, which is 90% against a water pollutant name as methylene blue (MB) under UV–Vis light. This sample also has shown a good catalytic stability i.e 80.7%. Moreover, for electrochemical performance analysis, cyclic voltammetry (CV), galvanostatic charge discharge (GCD) and electrochemical impedance spectroscopic (EIS) tests were also performed. Among of Co-P, Co-GC and Co-SF samples, Co-SF sample has offered 1080.32 F/g specific capacitance and 86.70% capacitance retention at higher scan rate i.e 10 A/g. Additionally, this optimized sample has also maintained 83.51% capacitance even after 5000 GCD cycles performed at 1 A/g, and good conductive nature. These extraordinary results have provided new platform for water purification and energy storage appliances. [ABSTRACT FROM AUTHOR]

Soft reliner and glaze are materials used over full or partial dental prosthesis to prevent excessive pressure on the supporting tissues. They are also indicated as supportive treatment for dental stomatitis, especially when modified by the addition of medications. The objective of the work was to evaluate the antimicrobial effect of silver-coated silica nanoparticles in a glaze and a soft reliner. The nanoparticles were synthesized, characterized, and tested by minimum inhibitory concentration (MIC) for C. albicans SC5314. Then, the nanoparticles were incorporated to a glaze and a soft reliner, which were called nanocomposites. Then, the nanocomposites were divided into six groups (n = 12): CG: glaze/reliner; CR: reliner; G1: glaze + 1% nanoparticles/reliner; G2: glaze + 2.5% nanoparticles/reliner; R1: reliner + 1%; R2: reliner + 2.5%. The nanocomposites were characterized by a goniometer and by a scanning electron microscope. The antibiofilm test was performed against C. albicans SC5314. According to the MIC results, the non-functionalized nanoparticles reduced fungal growth at 1000 μg/mL and the functionalized nanoparticles at 2000 μg/mL. The functionalized nanoparticle had a superior dispersion being selected for the antibiofilm test. There was a reduction of 64% in CFU/specimen count for the glaze, not statistically significant (p = 0.244). For the soft reliner, there was an increase in CFU/specimen with the presence of nanoparticles, still not statistically significant (p = 0.264). In conclusion, it is necessary to conduct new studies to increase the release of silver, thus improving nanoparticles' antifungal potential. [ABSTRACT FROM AUTHOR]

Silver nanoparticles was reflected a powerful antimicrobial agents newly exclusively after growing incidence of diseases related with biofilm and multi-drug resistant pathogens which essential required to find a different path to eliminate that's challenge. So the aim of present study was to synthesize silver nanoparticles through biological method using bacteria Eschriesca coli. Biological silver nanoparticles were described by several techniques. The UV-visible spectrophotometric indicated absorbance peak at 246 to 356 nm, Fourier Transformer Infrared analysis (FTIR) revealed that carboxylic groups and poly phenolic groups are enclosed on the surface of both silver nanoparticles creating stabilized nanoparticles, and by scanning electron microscope (SEM), which shown that the biosynthesized silver nanoparticles were spherical in size 26.22 to 31.44 nm. Optimization of silver nanoparticle biosynthesis by E. coli was performed for parameters (temperature and pH and concentration of silver nitrate solution) and the results discovered that temperature 60°C, pH 7 and 3 M silver nitrate concentration were the optimum conditions for silver Nano particles biosynthesis by E. coli isolated from clinical samples of Thi - Qar (Nassryah) city-south Iraq. [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]

Staphylococcus aureus (S. aureus) is a Gram-positive bacteria considered one of the leading causes of community and hospital-acquired illnesses or public health concerns. Antibiotic resistance in this microorganism is one of the greatest issues in global health care. The use of metal nanoparticles and their oxides is one of the potential approaches to combating bacteria resistance to antibiotics. The antibacterial properties of ZnO NPs against enterotoxigenic S. aureus were studied. ZnO NPs were tested in vitro by agar diffusion test. They resulted in 26 and 22 mm zones of inhibition for a size of 20 nm and a concentration of 20 mM against 105 and 107 CFU/mL S. aureus, respectively. The MIC of ZnO NPs of various sizes, 20 and 50 nm, with 105 CFU/mL was 2.5 and 5 mM, respectively. MIC with 107 CFU/mL was five mM for 20 and 50 nm ZnO NPs. Further, the highest growth reduction percentage, 98.99% in the counts of S. aureus was achieved by ZnO NPs of size 20 nm and concentration of 10 mM. Moreover, the obtained ELISA results indicated a significantly decreased concentration of enterotoxin A with all concentrations and sizes of ZnO NPs. PCR analysis showed a significant effect on sea gene in response to ZnO NPs treatments leading to loss of the gene, unlike the unaffected nuc gene. Moreover, morphological changes and cell shape distortion were detected by scanning electron microscope for bacterial cells treated with ZnO NPs. [ABSTRACT FROM AUTHOR]

In this work, hydrothermal synthesis of NiO nanoparticles in aqueous solutions at higher temperatures was used. An investigation of its optical and electrical capabilities might be done in many ways. As a result, the size and structure of NiO nanoparticles were characterised using a scanning electron microscope. A powder X-ray diffractometer was used to measure experimentally the crystallite grain size and dislocation density, which were computed using the Scherer formula. The functional groups of the title nanoparticles were easily distinguishable in the FTIR spectrum. After optical absorption analyses, NiO nanoparticles were shown to have optimised UV-Visible transmittance. The density functional theory (B3LYP) was used to compute the bonding of molecular properties of NiO in the ground state using the basis sets 6-311+G (d, p) and 6-311++G (d, p). There is evidence of charge transfer in molecules based on the computed molecular electrostatic potential (MESP), Thermodynamic properties, HOMO and LUMO energies determined. The scientific applications of this NiO nanomaterial would be well served by this material. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) nanostructures are systems with many fascinating novel properties that can be used to study new science and have significant promise for applications. In this study, graphene oxide was prepared using the modified Hummer's method. In addition, potassium ferrite is a good candidate for biomedical application, as iron and potassium are biocompatible and non-toxic materials. Mg0.85K0.3Fe2O4/GO nanocomposites were prepared by the citrate auto-combustion method. The effect of adding GO to Mg0.85K0.3Fe2O4 on structure, morphology, electrical, and magnetic properties was discussed. Samples under investigation were characterized using XRD, infrared spectroscopy (IR), high-resolution transmission electron microscopy (HRTEM), and atomic force microscopy (AFM). The crystallite size of prepared samples was decreased from 28.098 to18.148 nm by increasing GO content. Scanning electron microscope (SEM) confirms the successful adhesion of Mg0.85K0.3Fe2O4 nanoparticles on graphene oxide sheets, which are dispersed in a metal oxide matrix. EDAX analysis confirms the existence of C, O, K, Mg, and Fe elements present in the samples. Magnetic properties were studied by VSM and Faraday's method. GO has a significant effect on the magnetic properties of nanocomposites. For instance, the saturation magnetization and Curie temperature have diverse values, which will be appropriate for numerous applications. [ABSTRACT FROM AUTHOR]

The Sr-doped ZnO nanoparticles have been synthesized by the chemical precipitation method at room temperature. The prepared nanoparticles are annealed at 500 °C for 4 h. The nanoparticles have been characterized using X-ray diffraction (XRD) technique, scanning electron microscope and UV–Vis spectroscopy. The XRD studies reveal the formation of a wurtzite geometry. The crystallite size, dislocation density and strain are examined as a function of Sr-doping concentration. The band gap of the prepared nanoparticles ranges from 3.46 eV to 3.56 eV. The nanoparticles have a higher hole concentration than electron concentration. Supercapacitor cells have been prepared by using synthesized nanoparticle electrodes and it is characterized using cyclic voltammetry (CV) by using KOH as an electrolyte solution. The calculated specific capacitance is high at a high doping concentration of 'Sr'. [Display omitted] • Wurtzite geometry undoped ZnO and Sr-doped ZnO nanoparticles have been prepared. • The crystallite size of the nanoparticles ranges from 28.46 to 33.45 nm. • The optical absorbance is enhanced due to doping and the observed band gap is blue-shift due to addition of the dopants. • The nanoparticles have high hole concentration and the charge carrier concentration increases at high doping concentration. • The high specific capacitance 500 F/g is observed in this study which corresponds to the Sr-doped ZnO (4 %) nanoparticles. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the incorporation of copper-modified niobium (Nb/Cu) nanoparticles at concentrations of 0.1 % and 0.3 wt% in a one-step adhesive (PacBond Adhesive). Thirty sound human third molars were randomly divided into three groups: control, 0.1NbCu, and 0.3NbCu. Specimens were restored with PacBond and resin composite OptiComp, Composite LC. Stick specimens (0.64 mm2) were obtained and subjected to microtensile bond strength (MTBS) testing (n = 10) using a universal testing machine at a rate of 0.5 mm/min after 24 h and 6 months. Scanning electron microscope (SEM) analysis, microhardness after 24 h and immersion in ethanol (HK) (n = 7), degree of conversion (DC) (n = 6), and surface mineral deposition (n = 3) were also conducted. Data were analyzed using two-way ANOVA for MTBS and HK, and one-way ANOVA for %SHL and DC, all of them were followed by Tukey's test (p < 0.05). For MTBS, statistical difference in storage times was observed for 0.1NbCu after 24 h (p = 0.007). There was no statistical difference between the control and 0.3NbCu regarding time and materials after 24 h and 6 months (p = 0.065). There was no statistical difference among the groups for DC (p = 0.278), but there was a significant difference among the groups for the factor of time in HK measurements (p = 0.047). The 0.1NbCu and 0.3NbCu groups exhibited absorbance Bands indicative of surface mineral deposition after 14 and 21 days, and the 0.3NbCu interface showed better preservation in SEM analysis. The concentration of 0.3 % NbCu in a one-step adhesive appears promising and may offer enhanced longevity for the tooth/restoration interface. [ABSTRACT FROM AUTHOR]

Nanoparticle agglomeration reduces the modification effect of nanocomposites, and there is a need to investigate a technique for evaluating the overall particle dispersion within the material, which in turn ensures the modification effect of the material. In this paper, a non-destructive testing technique for nanoparticle dispersion based on nonlinear ultrasonic (NLUS) is proposed to rapidly assess the overall nanoparticle dispersion within a material. An interfacial mismatch model describing different degrees of nanoparticle agglomeration was firstly developed, and then the nonlinear acoustic response of the nanoparticle-dielectric system was quantitatively solved, and the theoretical model was validated in conjunction with NLUS tests. The experimental results show that agglomerated interfaces are the source of the nonlinear response of nanodielectrics and that the microscopically generated nonlinear effects can be equivalently accumulated to the mesoscopic domain, with the error in the theoretically calculated values of the two being less than 5%; The NLUS technique eliminates the need for cumbersome steps such as particle size counting, and its small number of rapid detection results are close to the statistical convergence of the particle size of the 250 particles accumulated in the imaging image of the scanning electron microscope, with an error of between 3% ∼ and 13%. With a single inspection area of 339 mm3, the NLUS technology significantly reduces evaluation time and cost while expanding the inspection area, offering the combined advantages of speed, wide field of view, and non-destructiveness. [Display omitted] • NLUS can assess the particle agglomeration degree quantitatively, rapidly, and nondestructively. • Agglomerated interface is the source of the nanodielectric nonlinearity. • The micro-regional nonlinear response can be equivalently accumulated to the mesoscopic domain. [ABSTRACT FROM AUTHOR]

Biofilms are matrix-enclosed communities of bacteria that are highly resistant to antibiotics. Adding nanomaterials with antibacterial activity to the implant surfaces may be a great solution against biofilm formation. Due to its potent and widespread antibacterial effect, silver nanoparticles were considered the most potent agent with different biological activities. In the present investigation, silver nanoparticles (AgNPs) were newly synthesized as antibiofilm agents using sugarcane process byproduct (molasses) and named Mo-capped AgNPs. The synthesized nanoparticles showed promising antimicrobial activity against S. aureus ATCC 6538 and C. albicans DAY185. Statistically designed optimization through response surface methodology was evaluated for maximum activity and better physical characteristics, namely the nanoparticles' size and polydispersity index (PDI), and it was revealed that molasses concentration was the main effective factor. Minimal biofilm eradication concentration (MBEC) of Mo-capped AgNPs against S. aureus ATCC 6538 and C. albicans DAY185 was 16 and 32 µg/mL, respectively. Scanning electron microscope study of Mo-capped AgNP-treated biofilm revealed that AgNPs penetrated the preformed biofilm and eradicated the microbial cells. The optimally synthesized Mo-capped AgNPs were spherically shaped, and the average size diameter ranged between 29 and 88 nm with high proportions of Ag+ element (78.0%) recorded. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the importance of molasses ingredients in capping and stabilizing the produced silver nanoparticles. [ABSTRACT FROM AUTHOR]

In the present study, self-assembled ZnO nanoparticles were synthesized via a hydrothermal method utilizing an aqueous extract of mentha pepperita L (peppermint) leaves. The effect of parameters, including the amount of extract, reaction time, and pH was investigated on the structure and morphology of synthesized nanoparticles. X-ray diffraction (XRD) patterns confirmed the formation of pure well-crystallized ZnO nanoparticles using a zinc nitrate solution (50 mM) and peppermint extract in a volume ratio of 6:1 at pH of 8 and 12. However, the morphology and crystallite size of the particles were different in pH of 8 and 12. Fourier transform infrared (FTIR) spectra confirmed the modification of the ZnO surface with peppermint extract components. Analysis of N 2 adsorption and desorption cycles showed the increment of surface area by about 5 times using peppermint extract. Scanning electron microscope (SEM) images revealed the formation of a self-assembled sphere structure using peppermint extract. Mechanism of dissolution-precipitation was proposed for green hydrothermal synthesis of ZnO nanoparticles, based on XRD and SEM results at various reaction times. The synthesized ZnO nanoparticles (reaction time of 24 h and pH of 8) were used to remove methylene blue (MB) dye from an aqueous solution, and adsorption and photocatalytic process were studied. The mass of the dye adsorbed per mass of the adsorbent, q t , grew up by increasing the initial dye concentration. Conversely, the photocatalytic degradation percent decreased. In addition, the final adsorption capacity in 50 mL of 30 ppm dye solution was almost the same in 0.01 and 0.05 g of ZnO, although it was smaller in 0.1 g of ZnO. The maximum degradation efficiency was derived by using 0.05 g ZnO. Self-assembled structure, high capacity of adsorption, and excellent photocatalytic properties were unique characteristics of the synthesized ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

Two different kinds of copper nanoparticles (CuNPs) (brown colour and greenish colour) were synthesised by using simple solution route and applied by exhaust method to achieve multidimensional functionalization on one of the most popular cellulose materials e.g., cotton fabric. The synthesised CuNPs imparted different colours to the said textile due to different conditions of synthesis and localized surface plasmon resonance. Physico-chemical characterizations of the synthesized nanoparticles were performed by using scanning electron microscope (SEM) and energy dispersive X-ray (EDX) analysis whereas the optical properties of the nanoparticles were studied using UV–visible spectroscopy. The prepared CuNPs of both the types demonstrated very good antimicrobial activity up to 97%. In addition, cotton fabric treated with CuNPs showed very high catalytic activity for reduction of 4-nitroaniline (4-NA) in presence of sodium borohydride to phenylene diamine (4-PD). Washing durability and rubbing fastness of the treated fabric have also been measured by following standard testing methods and found to be very good with a rating 4. [ABSTRACT FROM AUTHOR]

This study aims at the characterisation of red and orange glass tesserae from the 4th-century Roman villa of Noheda (Spain). Due to the limited number of analyses available for such ancient materials, many questions remain unanswered about the production processes in the Roman period. Six samples were chosen for their hue variations, including two samples showing banded patterns of red and orange. Differences in copper speciation were investigated by X-ray absorption spectroscopy and compared with colour and compositional variations obtained by EPMA. The shapes and sizes of colouring crystals could be investigated using scanning and transmission electron microscope imaging. The brown-red colour is due to metallic copper nano-particles and corresponds to a low-copper and low-lead group usually described in the literature. The orange samples and bands are coloured by copper oxide C u 2 O nanoparticles with remaining Cu+ in the glass and have greater contents of Cu. Compositional analyses reveal that the same base glass is used in the red and orange bands with additions of Cu, Sn, Pb and probable Fe. Furthermore, based on our results and on the literature review, a high-copper low-lead group of glasses highlights the variability of compositions observed in cuprite colours. [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]

In this work, the azo dye Congo red (CR) was degraded by a Fe–In2O3 catalyst under the irradiation of ultrasonic. The Fe–In2O3 catalyst was prepared by a fast and moderate solvothermal method followed by the characterization of X-ray diffraction and scanning electron microscope. The effects of operating parameters, such as catalyst composition, catalyst dosage, initial dye concentration, ultrasonic power and ultrasonic frequency on degradation process were discussed. In the experiment, the optimum CR removal of 97.75% in 60 min was achieved under the conditions, i.e., catalyst dosage of 0.06 g ⋅ L − 1 , CR concentration of 10 mg ⋅ L − 1 , ultrasonic frequency of 45 kHz and ultrasonic power of 100 W. Besides, the CR degradation behavior by the catalyst with ultrasonic is well in accordance with the first-order kinetic model. A spherical Fe–In2O3 nanocatalyst with good crystalline structure was successfully synthesized, and the excellent catalytic degradation efficiency for the azo dye congo red under ultrasonic irradiation was shown. The congo red degradation process was fostered by Fe–In2O3 catalyst compared with that of the blank and pure In2O3, which is well in accordance with the first order kinetic model. [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]

Purpose: This study aims to fabricate and investigate the tribological performance of ultra-high molecular weight polyethylene (UHMWPE)-based composite materials reinforced with 0.5, 1 and 2 weight percentage of graphene nanoplatelets (GNPs) while keeping the weight percentage of vitamin C constant at 2% for each composite. Design/methodology/approach: In this paper, the composites were fabricated using hot pressing, and the dispersion of GNP/vitamin C/UHMWPE hybrid composite was investigated by X-ray diffraction. Experimental trials were performed according to ASTM F732 on a reciprocating sliding tribometer (pin-on-disc) at human body temperature of 37 ± 1 °C, for a load of 52 N, to assess the role of these fillers on the tribological properties of UHMWPE against Ti6Al4V counter body material under dry and lubricating (human serum) environment. Findings: In this study, it has been observed that friction and wear behavior of the developed composites improve with increase in weight percentage of GNP, and human serum adheres to the surface of the composite pins upon sliding, resulting in the formation of a film, which results in better wear resistance of the composite pins under human serum lubrication than dry sliding. Scanning electron microscope was used to investigate the worn surface morphological examination of the composite materials. Specific wear rate of 0.76 × 10−7 mm3/Nm was attained for 2 Wt.% GNP-filled composite under human serum lubrication. Practical implications: The results indicate the compatibility of the composite material used in this study and suggested the in vitro implant application. Originality/value: The presented work includes novel study of synergistic effect of GNP (which acts as a solid lubricant) and vitamin C (added as an antioxidant) on the tribological performance of UHMWPE under dry and human serum lubrication. [ABSTRACT FROM AUTHOR]

Nanoparticles have been used to overcome the limitations of oral drug delivery. This study was performed to examine the effects of modifying Digitaria exilis starch by cross-linking with multifunctional excipients: citric acid (CA) and sodium tripolyphosphate (STPP) to produce starch citrate and phosphate respectively at 20 % concentration. Thereafter, nanoparticles were synthesized via the nanoprecipitation method in the presence of Tween® 80, using ibuprofen as the model drug. The physicochemical properties of the modified starch were evaluated and the nanoparticles characterized by the encapsulation efficiciency, loading capacity, particle size, polydispersity index, scanning electron microscope (SEM), fourier transform infrared spectroscopy(FTIR), in vitro drug release and release kinetics. Results show that both cross-linkers improved the physicochemical properties of the starch, and produced particles in the nanometer range (616 nm and 933 nm) for citric acid and sodium tripolyphosphate nanoparticles respectively. Spherical and pitted particles corresponding to citric acid and sodium tripolyphosphate nanoparticles respectively were produced and they both showed a controlled release of ibuprofen from the formulation and both followed the Higuchi kinetic model with R2 values that exhibited a non-fickian diffusion pattern. This study revealed that the two excipients had different effects on the size and morphology of the nanoparticles and controlled the release of drug from the nanoparticles. [ABSTRACT FROM AUTHOR]

Background: Mucoadhesive nasal gel provide a good platform of drug delivery to the nasal mucosa. We aimed to detect the histologic effect of mucoadhesive loaded antibiotic to the nasal mucosa of the rabbits by light microscope and scanning electron microscope to detect the ultra-structure changes. Methods: A total of 36 adult male rabbits divided into 3 groups. Vehicle control group (A): Non-diseased, receives intranasal mucoadhesive gel. group (B): Non-diseased, receives intranasal Neomycin-loaded mucoadhesive gel. group (C): Non-diseased, receives intranasal ciprofloxacin loaded mucoadhesive gel. Part of the nasal mucosa was stained by Toluidine blue for scanning light microscopy. Other part of the Nasal mucosa was immediately fixed in 1.5% gluteraldehyde in phosphate buffered saline (pH 7.4) for 2 h at room temperature, and determination of morphological properties and microscopic ultra-structure was performed. Results: There is statistically insignificant difference of histological changes in inflammatory cells of Ciprofloxacin group also surface mucosa showing deciliation of wide area of the epithelial cells and nasal mucosa showing necrobiosis of numerous epithelial cells. Congestion is significantly higher in Neomycin group (46.1%), than Ciprofloxacin group (7.7%). Conclusion: Antibiotic loaded mucoadhesive gel showed minimal damage with preserved integrity of the nasal mucosa, so it could be considered safe vehicle for delivering topical antibiotics. [ABSTRACT FROM AUTHOR]

Nanoparticles of tin oxide (SnO2) doped with iron oxide (α-Fe2O3) and Europium oxide (Eu2O3) were synthesized through the solid-state synthesis method. The phase analysis confirms the tetragonal rutile phase for all samples using X-ray diffraction (XRD). The luminescence intensity and expansion of lattice depend on doping percentage, which validates the successful blending of Fe and Eu in SnO2 lattice. The lattice dislocation and strain are calculated using the Williamson–Hall (WH) parcel, which also supports the development of the grain boundary in the doped samples. An increase in a large number of recombination centers leads to quenching in optical spectra by using the photoluminescence (PL) spectrum, and the shift in the band gap estimated from UV–visible absorption spectra confirms the impact of the grain boundary. A vibrating sample magnetometer (VSM) under the physical properties measurement system (PPMS) confirms room temperature ferromagnetism RTFM, and a scanning electron microscope (SEM) showed clear images of grain boundaries. Conductivity studies show an increase in resistance to Fe/Eu doping. Among all the tailored samples, Sn(1−x)Fex/EuO2, for x = 0.04 wt. % and 0.02 wt. % proved as a potential candidate for magneto-opto-electronic, i.e., spintronics device applications. [ABSTRACT FROM AUTHOR]

In this study, zinc ferrite nanoparticles with a diameter of less than 50 nm were synthesized. Using XRD (X-ray Diffraction), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) the morphology and structure of this ferrite was investigated. The formation of spinel phase in Zn-Mn ferrite was shown by X-ray analysis. SEM photograph has shown spherical shape of nanoparticles and the dimensions of the samples were confirmed by Transmission Electron Microscope (TEM) at the nanoscale. Using the Debye-Scherrer formula, the size of Mn ferrite nanoparticle crystals was calculated to be about 13 nm. To check the properties related to the sensitivity of this ferrite, a fully insulated Plexiglass box was used and placed in it. By injecting 1 mL of liquid and vapor it, we will have 200 ppm concentration of each sample in this box. Then the injected vapored sample in this box is exposed to the ferrite. After this step, the conductivity of the ferrite in a closed circuit was changed. By changing the sample type, amount of this conductivity was varied. Five gases were tested in this project: ethanol, dimethyl formamid, carbon tetrachloride, acetonitrile and acetone. Among these samples the carbon tetrachloride had the best sensitivity performance. Finally, the sensor equation for carbon tetrachloride was extracted by applying different concentrations of it from 20 to 200 ppm. [ABSTRACT FROM AUTHOR]

The aim of this study is to produce multifunctional cotton fabric with improved mechanical performance by utilizing the potentiality of ZnO nanoparticles. Synthesized ZnO nanoparticles are immobilized on the cotton fabric with the following recipes: (i) only ZnO nanoparticles, (ii) ZnO nanoparticles with an acrylic binder, and (iii) ZnO nanoparticles with polyethylene wax emulsion and binder. SEM (Scanning Electron Microscope) and EDS (Dispersive Energy Spectroscopy) are used to investigate the surface morphology. For analysis of functional properties antimicrobial activity, ultraviolet (UV) protection ability, and crease resistance are measured. Several mechanical properties are also investigated. The results show that the treatment with the first and second recipes improves the functional properties but degrades the mechanical properties. In contrast, nano ZnO treatment with the third recipe improves mechanical as well as functional properties. Specifically, the nano deposition by this recipe increases the tensile strength, tearing strength, elongation, abrasion, and pilling resistance. Therefore, the findings in this research will boost up the confidence of textile researchers and manufacturers for the use of nano ZnO and understanding its characteristics in the production of valuable functional textiles. [ABSTRACT FROM AUTHOR]

ZnO nanoparticles show great potential for photodegradation applications due to their excellent physical and chemical properties. Finding a greener approach to producing nanoparticles is of the utmost importance for multidimensional application purposes. In the present study, the ZnO nanoparticles were synthesized by a simple combustion method at 400 °C, using jackfruit extract. X-ray diffraction (XRD) pattern revealed a crystalline structure of the nanoparticles. Scanning electron microscope (SEM), Raman spectroscopy, BET surface area were used to further characterize the synthesized nanoparticles. Further, it has been used as a photocatalyst for the degradation of one of the organic pollutant methylene blue dye. In general, the method employed here is a greener approach to synthesize ZnO nanoparticles with good photocatalytic activity. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles are produced using simple auto combustion methods with honey as a metal-stabilizing and -reducing agent. Herein, α-Fe2O3 nanoparticles are produced using an iron nitrate precursor. These prepared samples are analyzed by an X-ray diffractometer (XRD), FTIR spectroscopy, UV-DRS, and a field-emission scanning electron microscope (FESEM) combined with energy-dispersive spectroscopy and a vibrating sample magnetometer (VSM). The XRD results confirm a rhombohedral structure with an R3 c ¯ space group single-phase formation of α-Fe2O3 in all samples. FESEM images reveal the different morphologies for the entire three samples. TEM analysis exhibits spherical shapes and their distribution on the surfaces. XPS spectroscopy confirms the Fe-2p and O-1s state and their valency. The VSM study shows strong ferromagnetic behavior. The prepared α-Fe2O3 nanoparticles exhibit exceptional charge carriers and radical production. The prepared sample retains excellent photocatalytic, antifungal and antibacterial activity. [ABSTRACT FROM AUTHOR]

Essential oils are composed of volatile components, and rapidly evaporate. It is desirable to formulate them in a cover protecting the essential oils against environmental conditions. Applying nanotechnology to preparing desirable formulations of essential oils can be provided in a cover along with controlled release, increased oil life and greater mobility. In this study, nanoparticles were prepared using polycaprolactone and chitosan aimed at encapsulation of Rosmarinus officinalis and Zataria multiflora essential oils. The nanoparticles were characterized in terms of size, polydispersity, encapsulation efficiency, and scanning electron microscope photomicrographs. The nanoparticles showed a positive surface charge ranging between +11.60 and +29.20 mV and a mean particle radius ranging between 181-407 nm. Encapsulation efficiency was obtained between 75.8-84.4% under different preparation conditions. The LC50 values of fumigant toxicity of R. officinalis essential oil and nanoparticles were equal to 103.53 and 112.64 μL/L air, and for Z. multiflora essential oil and nanoparticles, they were equal to 195.13 and 206.66 μL/L air, respectively for 24 h exposure time against Tribolium confusum. The effectiveness of non- formulated essential oils was significantly (P < 0.05) lower than nanoencapsulated oils in the confused flour beetle adults for a long period under the same condition, due to the sustained release of the essentials provided by the formulation. [ABSTRACT FROM AUTHOR]