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The constraints on the effectiveness of nuclear polyhedrosis virus (NPV) as biocontrol are usually due to environmental factors such as temperature and ultraviolet (UV) exposure. Zeolite has been commonly used as a carrier or delivery system for nuclear polyhedrosis viruses. In this study, zeolite powder was reduced into nanosized particles by beads milling method and was investigated for the effect of its concentration in the delivery system of Helicoverpa armigera nuclear polyhedrosis virus (HaNPV1) on the lethal time against the larvae Crocidolomia pavonana. The formulation used three concentrations of nanozeolite suspension, 0.5, 1, 1.5, and 2 wt.% applied for each 4 x 107 of HaNPV1. A randomized block design (RBD) method was applied with 3 replications. The results showed that the scanning electron microscope (SEM) from nanozeolite was seen coating the entire surface of the HaNPV1 polyhedra and an increase of zeolite concentration caused acceleration of the lethal time of C. pavonana instar III. Thus, the fastest lethal time was 1.2 days receiving a concentration of 2 wt.%, which was significantly higher compared to without delivery (2.9 days). The increase of the zeolite concentration up to 2 wt.% in the delivery system for HaNPV1 improved their performance on lethal time and mortality against C. pavonana. It was concluded that nanozeolite as a delivery system enhanced and created a synergy in infecting C. pavonana. [ABSTRACT FROM AUTHOR]

The aim of the present work is employing BaCe0.85Yb0.15O3-δ nanoparticles for improving textural properties and performances of proton exchange membranes based on polybenzimodazole (PBI) at high operation temperature. The novel proton conducting membrane nanocomposites are prepared by using various weight percent amounts of BaCe0.85Yb0.15O3-δ nanomaterial by dispersing into polybenzimidazole using solution casting method. The nanocomposites membranes properties are studied using AC impedance spectroscopy, scanning electron microscope (SEM) coupled with energy dispersive X-ray (EDX) spectroscopy and thermo gravimetric analysis (TGA). The prepared nanocomposites membranes reveal higher acid uptake, better protonic conductivity and thermal stability compared to pure PBI membranes. Highest acid uptake and protonic conductivity properties are obtained for phosphoric acid-doped PBI nanocomposites membranes while the inorganic compotent amount in the membrane composite is 5 wt.%. The prepared nanocomposites membranes are used in fuel cell sytems. Polarization property and power curves of the prepared membranes are studied at 180 °C. The results show that the obtained PBI/BaCe0.85Yb0.15O3-δ nanocomposites has excelent potentials as proton exchanger membranes for high temperature fuel cell systems. [ABSTRACT FROM AUTHOR]

The main aim of this research work was to develop controlled drug delivery systems based on nanotechnology. Chitosan nanoparticles (CSNPs) were selected as a nanocarrier for the selected antibiotic drugs tetracycline, gentamycin and ciprofloxacin. CSNPs were prepared from chitosan solution by using tripolyphosphate (TPP) via ionic gelation method. Then the prepared high performance CSNPs were loaded with three different antibiotics to form nanocomposite from antibiotic loaded chitosan nanoparticles. Then the prepared nanocomposite used as superior antibacterial materials with minimum toxicity. Samples of cotton (100%) and (50:50) cotton/polyester blended fabrics were treated with different concentrations of this composite to impart antibacterial activity. Results showed that the treated fabrics with chitosan nanoparticles and its nanocomposite with different antibiotics were inhibited the growth of both Gram-positive and Gram-negative bacteria. The Fourier Transform Infrared spectroscopy (FTIR) and Scanning Electron Microscope (SEM) analysis exposed the embedding of chitosan nanoparticles into fabrics and their antibiotics loaded. [ABSTRACT FROM AUTHOR]

In the present work, both the iron nanoparticles (INPs) by the chemical reduction method were synthesized and the hydrogen gas was produced during the reaction. In the nanoparticle synthesis method, the leach solution prepared from the branches and leaves of Pinus brutia , iron accumulator plant, was used as an iron ion source whilst sodium borohydride (NaBH 4) was used as the reductant agent. The synthesized iron nanoparticles were characterized by UV–vis spectrophotometer, X-ray Diffractometer (XRD), Scanning Electron Microscope (SEM), and Energy Dispersive X-ray Spectroscopy (EDX). According to the characterization results; INPs had the phases of magnetite, goethite, lepidocrocite, and zero-valent iron. The structures of INPs were porous and nearly spherical; also, the average particle size of INPs was determined to be 82.19 nm. INPs had the elements of O, Fe, Ca, Na, Mg, and Cl in descending order. On the other hand, the amount of the generated hydrogen gas was measured by the volume of the displaced water. The effects of temperature, pH, NaBH 4 amount, and poly vinyl pyrrolidone (PVP) amount on the hydrogen gas production were investigated. The results showed that temperature of 65 °C, pH = 9.0, 2.50 g NaBH 4 , and 1.0 g PVP were determined as the optimum conditions for H 2(g) production and 6000 ± 50 mL H 2(g) volume was produced under the optimum environmental conditions. The reaction kinetics was evaluated and the reaction order was found as approximately 1.3523 order and it was obtained that the reaction rate constants increased with increase in temperature as it was expected from the temperature effect. The activation energy, enthalpy, and entropy of the reaction were determined to be 46.86 kJ/mol, 44.19 kJ/mol, and –105.52 J/mol. K, respectively. Image 1 • H 2(g) was produced during iron nanoparticles synthesis with an accumulator plant. • The optimum conditions were determined as 65 °C, pH = 9, 2.5 g NaBH 4 , and 1 g PVP. • 6000 ± 50 mL H 2(g) could be produced in 80 min under the optimum conditions. • The reaction order was found as 1.35 and the studied process was endothermic. [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 the present study, La1 − xCrxFeO3 (x = 0.0, 0.3, 0.6, 0.9, 1.0) was synthesized by micro-emulsion route and characterized by X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Scanning electron microscope (SEM), Energy-dispersive X-ray (EDX) techniques. The dielectric, ferroelectric and photocatalytic properties were investigated and compared with un-doped material. The XRD analysis revealed orthorhombic geometry of La1 − xCrxFeO3 (x = 0.0, 0.3, 0.6, 0.9, 1.0), Cr was doped successfully into the lattice structure of LaFeO3 and particles were spherical and in agglomerated form. The grain sizes were recorded to be 15, 16.9, 17.1, 17.65 and 18.3 (nm) for La1 − xCrxFeO3 (x = 0.0, 0.3, 0.6, 0.9, 1.0), respectively. EDX analysis confirmed the purity of LaCrFeO3 samples. The lattice parameters, bulk density, X-ray density, crystalline size and porosity were determined were also determined of all the La1 − xCrxFeO3 samples. The dielectric constant and dielectric loss values decreased at higher frequency and Cr concentration affected the dielectric properties. The photocatalytic activity (PCA) was evaluated by degrading Congo Red (CR) dye under solar light irradiation and up to 85.43% dye degradation was achieved within 45 min of irradiation. Phyto-toxicity analysis before and after dye degradation was performed, which revealed the toxicity reduction in response of dye degradation. Results revealed that lanthanum ferrite (perovskite) doping with Cr could possibly be employed to enhance the ferroelectric, dielectric and photocatalytic properties. [ABSTRACT FROM AUTHOR]

The novelty of this present work is to investigate the anti-bacterial and anti-fungal activity of the green synthesized titanium dioxide (TiO2) nanoparticles using leaf extract of Mentha arvensis, titanium tetraisopropoxide act as the precursor and leaf extract act as the reducing agent. Synthesized nanoparticles were characterized by using X-ray diffraction, UV–Visible absorbance spectroscopy, Fourier transform infrared spectroscopy and scanning electron microscopy methods. The X-ray diffraction study of the synthesized nanoparticles shows the crystalline structure and the incidence of peaks at 25.27° corresponds to 110 anatase form. Scanning electron microscope study revealed that the synthesized nanoparticle was spherical in shape and the average size of the synthesized nanoparticles was found to be the range of 20–70 nm. Green synthesized TiO2nanoparticle exhibited interesting antibacterial and antifungal activity against selected microorganism. [ABSTRACT FROM AUTHOR]

A correction has been made to Figure 1 to show the morphology of ambient nanoparticles in Chiang Mai, Thailand, as observed in the scanning electron microscope (SEM) analysis [[2]] - the newly added reference 92. Ambient Nanoparticles (PM 0.1) Mapping in Thailand. A correction has been made to "Phairuang et al. (2021) [32], reported on the source apportionment of PM SB 0.1 sb particles in Bangkok", the updated one should be "Phairuang et al. (2021) [53], reported on the source apportionment of PM SB 0.1 sb particles in Bangkok". [Extracted from the article]

The antifungal and aflatoxin B1 (AFB1) inhibitory effect of chemically characterised Callistemon lanceolatus essential oil (CLEO), chitosan nanoparticles, and CLEO loaded chitosan nanoparticles (CLEO-ChNPs) were investigated. Scanning electron microscope observation exhibited the spherical shape of prepared CLEO-ChNPs with an average range of 20–70 nm. An in-vitro release study revealed the controlled volatilisation of CLEO from CLEO-ChNPs. The CLEO-ChNPs caused complete inhibition of growth (4.5 µl/ml) and AFB1 (4.0 µl/ml) production by A. flavus at a low dose compared to free CLEO (5.0 µl/ml). The antifungal and AFB1 inhibitory toxicity of CLEO-ChNPs were elucidated using biochemical (effect on ergosterol biosynthesis, membrane cations, mitochondrial membrane potential, C-sources utilisation and cellular methylglyoxal level) and in-silico (interaction with the gene product Erg 28, Cytochrome c oxidase subunit Va, Omt-A, Ver-1, and Nor-1) approaches. [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]

Introduction: When sealer is adapted well to the root canal wall, there is less tendency for microleakage and strength of root canal is enhanced. Therefore, it is important for the sealer to possess good tubular penetration depth and adaptation to dentinal walls. Aim: To compare the effects of sonic activation of 5.25% NaOCl and incorporation of ZnO nanoparticles in AH Plus sealer on tubular sealer penetration. Materials and Methods: Forty extracted human mandibular premolars with a single root canal were used for this invitro study from October 2019 to January 2020. All teeth were prepared upto F3 with Pro Taper Universal rotary system. Teeth were randomly divided into four groups of 10 teeth each. Group I (control) included teeth obturated using AH plus sealer, Group II: teeth obturated using AH plus sealer incorporated with nanoparticles, Group III: teeth prepared along with sonic activation of the irrigant followed by obturation using AH plus sealer and Group IV: teeth prepared along with sonic activation of the irrigants followed by obturation with AH plus sealer incorporated with ZnO nanoparticles. Irrigation was achieved with 5.25% sodium hypochlorite. The canals were dried and obturated using respective sealers and single gutta percha cones. After storage at 37°C and 100% humidity, the roots were split into two halves and sealer penetration in the dentinal tubules was examined by using scanning electron microscope. The values obtained were statistically analysed using Oneway analysis of variance (ANOVA) with significant p-value less than 0.05. Results: In all the groups, sealer penetrated into the dentinal tubules. There was enhanced tubular sealer penetration (289.57±59.43 μm) after sonic activation of the irrigant (group 3) followed by that on addition of nanoparticles to the sealers (group 2) (278.21±71.24 μm) and the least was seen in the control group (group 1) (211.5±66.33 μm). The combined effect of both i.e., use of sonic activation of irrigant followed by obturation using modified sealer with gutta percha (group 4) (318.64±88.27 μm) showed greatest tubular sealer penetration depth. Conclusion: Incorporation of nanoparticles aids in improving sealer penetration which is further enhanced in case of sonic activation during irrigation. [ABSTRACT FROM AUTHOR]

Ionotropic gelation followed by polyelectrolyte complexion was used for the synthesis of nanoparticles based on sodium alginate (NaAL) and chitosan (CS) for encapsulation of ibuprofen (IBP), Fourier transform infrared spectroscopy, differential scanning calorimetry, field-emission scanning electron microscopes, percentage of encapsulation efficiency and loading capacity have been used to confirm the synthesis and encapsulation of IBP. The results obtained show that they have a size of around 100 nm. In vitro drug release and evaluation of anti-inflammatory activity in different media indicate that the nanoparticles are pH-sensitive and permit the protection of the drug against total dissolution in the gastric medium, control its release, and it increases the solubility and biological activity of IBP. The analytical data of the in vitro drug release in the simulated gastric fluid (SGF), simulated interstitial fluid (SIF) and phosphate buffered saline (PBS) were fitted to the different kinetic models (zero-order, first-order, Higuchi, Korsmeyer–Pepass and Kopcha), and the results indicate that IBP is released by diffusion-controlled in SIF and PBS, and by erosion-controlled in the SGF. The toxicity of nanoparticles was tested against Artemia salina that displayed non-toxicity effects. In vitro biodegradation by lysozyme and all the results obtained indicated that a NaAL/CS nanoparticles are a promising system for IBP release that can achieve pseudo-zero-order kinetics. [ABSTRACT FROM AUTHOR]

Green synthesized metallic nanoparticles are continually receiving attention as antimicrobial agents and catalyst for degradation of a host of organic compounds. In this study, silver nanoparticles were synthesized using Aspilia pluriseta extracts and evaluated for their antimicrobial and photocatalytic activity. Using a UV–Vis spectrophotometer, the surface plasmon resonance observed at 427 nm indicated the materialization of silver nanoparticles. Probable vibrational stretches that are characteristic of silver nanoparticles such as –OH stretching vibrations and –CH2 vibrational stretch, were identified using an FT-IR spectrophotometer. In order to understand the morphology and composition of the synthesized nanoparticles, they were studied further using scanning electron microscope (SEM), dynamic light scattering analyzer (DLS), transmission electron microscope (TEM) and X-ray diffractometer (XRD) hence revealing formation of crystalline, spherically shaped silver nanoparticles. The synthesized silver nanoparticles (AgNPs), exhibited broad-spectrum activity which was concentration dependent against; two-gram positive bacteria (Bacillus subtilis and Staphylococcus aureus), two-gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and the fungal (Candida albicans). Effectiveness of the nanomaterials in photocatalytic degradation was based on irradiation time. Decolorization and degradation of the dye took less than 30 min. [ABSTRACT FROM AUTHOR]

• A mechanism is presented to illustrate different observations of cathode deposits. • Primary particle size was reduced by increasing the quench gas velocity. • The crystallite size of produced nanoparticles increases with the nitrogen content. • Raising the arc current from 12 to 50 A leads to a yield enhancement of factor ten. Arc discharge synthesis has industrial relevance due to its low cost and scale-up potential. The production of titanium nitride nanoparticles was achieved by direct current arc discharge in an atmospheric-pressured ambient composed of N 2 and Ar. We systematically investigated the effect of the synthesis parameters, including quench gas velocity, quench gas composition, and applied arc current, on the particle quality, yield, and size. It is found that increasing quench gas velocity enables to produce particles with a primary size of 10–15 nm, while titanium nitride particles of 20–50 nm are produced at low quench gas velocity based on scanning electron microscope (SEM) analysis. X-ray diffraction (XRD) results indicated that titanium nitride particles produced at various nitrogen compositions are almost stoichiometric, while the crystallite size increases almost 20 nm when increasing nitrogen contents in the quench gas. Quench gas composition also has a significant impact on the arc voltage as well as particle production rate. When increasing the nitrogen concentration from 20% to 100%, the production rate can be enhanced by a factor of three. Besides, raising the applied arc current from 12 A to 50 A leads to a yield enhancement of factor 10. According to the Brunauer-Emmett-Teller (BET) measurement, the increase of applied arc current has a limited impact on primary particle size. The enhancement in particle production rate is mainly reflected by the larger agglomerate sizes and agglomerate number concentration. Additionally, based on experimental observations and previous studies, a mechanism is presented to explain the growth of deposits on the cathode tip. [ABSTRACT FROM AUTHOR]

Lotus seed starch (LS) was enzymatically hydrolyzed by pullulanase, β-amylase and α-amylase to obtain three types of starch nanoparticles (SNPs): P-SNPs, β-SNPs and α-SNPs, respectively. The structure and physicochemical properties of lotus seed starch nanoparticles (LS-SNPs) were systematically studied by Laser particle size analysis, Scanning electron microscope (SEM), X-ray diffraction (XRD), Raman spectrometry, Nuclear magnetic resonance (NMR) and Gel permeation chromatography (GPC). The results showed that compared to LS (10,466.7 ± 230.9 nm), the D [3,2] of P-SNPs were (334.7 ± 16.2), which indicated that LS was decomposed into LS-SNPs with low degree of polymerization. P-SNPs showed the highest efficiency, with 81.74% of samples reaching the nanoscale. The particle size order was LS > β-SNPs (α-SNPs) > P-SNPs. XRD results showed P-SNPs had the highest crystallinity 65.07%. During preparation of LS-SNPs, crystal region was destroyed, and double helix structure became stronger, but no new functional groups were introduced. P-SNPs had the smallest amorphous area and also showed a minimal molecular weight and the broadest molecular weight distribution. P-SNPs had the smallest particle size and the highest crystallinity, so P-SNPs were the best of all LS-SNPs. • The highest crystallinity of lotus seed starch nanoparticles (LS-SNPs) was 65.07%. • The method to prepare LS-SNPs was high-efficiency and green. • Different formation mechanisms of LS-SNPs were found and analyzed. [ABSTRACT FROM AUTHOR]

Ternary Cu/TiO 2 /rGO photocatalysts with varying Cu and graphene loadings were prepared by a solvothermal method. Pure anatase TiO 2 hollow spheres (THS) were prepared with titanium butoxide, ethanol, ammonium sulphate, and urea via a hydrothermal method; Cu nanoparticles were subsequently loaded on the surface of the hollow spheres by wet impregnation. During the solvothermal process, deposition and well dispersion of Cu–TiO 2 hollow spheres composites onto graphene oxide surface, as well as the reduction of graphene oxide to graphene were achieved. The morphological and structural properties of the prepared samples were characterized by Brunauer-Emmett-Tellet (BET), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), UV–vis DRS, and Photoluminescence (PL). The activity of the prepared catalyst was tested for hydrogen production via simultaneous photocatalytic water-splitting and glycerol reforming under natural solar light irradiation. The excellent photocatalytic activity of the ternary Cu/THS/graphene catalyst is attributed to the graphene sheets, which acts as both storage and transferor of electrons generated at the Cu and TiO 2 heterojunction, thus increasing the electron-hole pair separation. Image 1 • A highly active ternary Cu/THS/Graphene catalyst was prepared. • Hydrogen production from glycerol with solar light was studied. • Optimum Cu and graphene loadings were 0.5 wt% and 4 wt%.respectively. • Highest activity of the optimized ternary catalyst is 147,000 μmol.g cat −1. [ABSTRACT FROM AUTHOR]

Micronization of polar drugs by the rapid expansion of supercritical solution (RESS) process is not successful in near critical pressure due to the extremely low solubility of the drugs in near-critical CO2. In this study, for the first time, micronization of aspirin was successfully performed by the rapid expansion of supercritical solution with solid co-solvent (RESS-SC) process in near-critical pressure by using menthol as solid co-solvent. To achieve this aim, some experiments were conducted to study the influences of expansion pressure ranging from 1 to 8 bar, pre-expansion temperature ranging from 30 to 70 °C, spray distance ranging from 2 to 6 cm, nozzle diameter ranging from 300 to 700 µm, and nozzle types (orifice - capillary) on the morphology and size of aspirin particles. The obtained particles were characterized by x-ray diffraction (XRD) and scanning electron microscope (SEM) analysis. Utilizing RESS-SC process in near-critical condition, aspirin particles in the range of 0.17–6.61 µm were obtained. [ABSTRACT FROM AUTHOR]

A well-organized, simplistic, and green route of chitin-glucan based zinc oxide nanoparticles (ChGC@ZnONPs) was synthesized using reducing and capping agent both in one as chitin-glucan complex (ChGC). Herein we report the bio-synthesis of Cur-ChGC@ZnONPs by the conjugation of curcumin (Cur) with ChGC@ZnONPs for the improvement of antioxidant and antibacterial activity. The synthesized nanoparticles were characterized by the UV–Visible (UV–Vis), particle size analyser, scanning electron microscope (SEM) with Energy-dispersive X-ray spectroscopy (EDX), Transmission electron microscope (TEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). Structure analysis, shape and crystalline size of nanomaterials were confirmed by scanning electron microscopy (SEM) and Transmission Electron Microscopy (TEM). The particle size analyser showed the particle size of nanomaterials and stability. Crystalline nature of both ChGC@ZnONPs and Cur-ChGC@ZnONPs were confirmed by the XRD spectra and FT-IR spectrum was used to examine the functional groups of nanomaterials. The antioxidant potential of conjugated nanomaterials were estimated using a DPPH free radical scavenging assay and ABTS+⁎ assay. This analysis showed that after loading of Cur, antioxidant activity increases. The antibacterial assessment of conjugated nanomaterials were tested by different microorganisms and showed excellent antibacterial activity. [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]

Infection and inflammation during wearing contact lenses are the problems for the users of daily soft contact lenses. All Gram-positive bacteria, Gram-negative bacteria, and fungi play a role in this problem. In past decades, nanoparticles have largely been studied and shown good antimicrobial activity against various microorganisms. The present study aimed to prepare, characterize, and evaluate zinc oxide nanoparticles (ZNPs) as antimicrobial agents against different microorganisms. The ZNPs were synthesized in a special structure using the sol-gel process and characterized by XRD, TEM, and EDX. Antimicrobial properties of ZNPs suspension were investigated against different microorganisms (i.e., Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli, and Candida albicans) by the Scanning Electron Microscopy of lens surfaces and pour plate method of immersed lens suspension for microbial enumeration. The XRD, TEM, and EDX spectrum showed hexagonal structure and no impurity in the nanoparticles with a size of about 20 to 40 nanometers. Sterilized suspension of ZNPs was applied against bacterial species, and the results indicated 4 logarithms (CFU/mL) microbial growth reduction for most Gram-positive and Gram-negative species, except for Pseudomonas aeruginosa that showed 3.5 logarithms (CFU/mL) growth reduction. Furthermore, 1 and 1.7 logarithms (CFU/mL) growth reduction were observed for Candida albicans, applying 250 and 500 ppm ZNPs suspension, respectively, which is an acceptable result for fungal growth inhibition. Findings of this study indicated that the suspensions of ZNPs with 250 and 500 ppm showed acceptable bacteriostatic and bactericidal effects. In vitro antimicrobial activity showed that the suspension of ZNPs with 250 ppm concentration could effectively cause a proper reduction and inhibition in the growth of both Gram-positive and Gram-negative microorganisms. Therefore, the results revealed the efficacy of the antibacterial properties of synthesized ZNPs suspension in aqueous media. ZNPs: Zinc oxide nanoparticles; XRD: X-ray diffraction; FWHM: Full width at half maximum; TEM: Transmission electron microscope; SEM: Scanning electron microscope; EDX: Energy-dispersive X-ray spectroscopy; S. aureus: Staphylococcus aureus; S. epidermidis: Staphylococcus epidermidis; L. monocytogenes: Listeria monocytogenes; B. subtilis: Bacillus subtilis; P. aeruginosa: Pseudomonas aeruginosa; S. typhi: Salmonella typhi; E. coli: Escherichia coli; C. albicans: Candida albicans; MK: Microbial keratitis; CLARE: Contact lens-induced acute red eye; CLPU: Contact lens-induced peripheral ulceration; IK: Infiltrative keratitis; AIK: Asymptomatic infiltrative keratitis; MIC: Minimum inhibitory concentration; MBC: Minimum bactericidal concentration; BHI: Brain heart infusion; TSB: Tryptic soy broth; BHIA: Brain heart infusion agar; TSA: Tryptone soya agar. [ABSTRACT FROM AUTHOR]

Electrically conductive nanocomposite system based on poly(butyl methacrylate) (PBMA) with different contents of neodymium-doped titanium dioxide (Nd-TiO2) was prepared by in situ free radical polymerization method. The effect of Nd-TiO2 on the morphology and structural properties of the composites was carried out by scanning electron microscope (SEM) and X-ray diffraction analysis (XRD). The temperature-dependent AC conductivity and DC electrical conductivity of PBMA/Nd-TiO2 nanocomposites were studied with respect to the different volume fraction of Nd-TiO2 nanoparticles. SEM and XRD patterns revealed the uniform dispersion and structural regularity of nanoparticles in the polymer matrix. The AC conductivity of PBMA and its composites were found to be increased with an increase in temperatures and frequencies. The activation energy and exponential factor were analyzed from AC conductivity and both results indicate the hopping conduction mechanism present in PBMA/Nd-TiO2 nanocomposite, which is responsible for the variation of conductivity with temperature also. The DC conductivity of nanocomposites was higher than pure PBMA and the conductivity increases with increase in the concentration of Nd-TiO2 nanoparticles. Experimental and theoretical investigations based on McCullough, Bueche, Scarisbrick, and Mamunya modeling were carried out to observe the DC conductivity differences induced by the addition of Nd-TiO2 nanoparticles in PBMA matrix. Among the various modeling studied here, Mamunya model shows better agreement with the experimental conductivity. [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]

The possibility of obtaining calcium carbonate nanoparticles from Achatina fulica shell through mechanochemical synthesis to be used as a modifying filler for polymer materials has been studied. The process of obtaining calcium carbonate nanopowders includes two stages: dry and wet milling processes. At the first stage, the collected shell was dry milled and undergone mechanical sieving to ≤50 μm. The shell particles were wet milled afterward with four different solvents (water, methanol, ethylene glycol, and ethanol) and washed using the decantation method. The particle size and shape were investigated on transmission electron microscopy, and twenty-three particle counts were examined using an iTEM image analyzer. Significantly, nanoparticle sizes ranging from 11.56 to 180.06 nm of calcium carbonate was achieved after the dry and wet milling processes. The size particles collected vary with the different solvents used, and calcium carbonate synthesis with ethanol offered the smallest organic particle size with the average size ranging within 13.48-42.90 nm. The effect of the solvent on the chemical characteristics such as the functional group, elemental composition, and carbonate ion of calcium carbonate nanopowders obtained from Achatina fulica shell was investigated. The chemical characterization was analyzed using Fourier transform infrared (FTIR) and a scanning electron microscope (SEM) equipped with an energy-dispersive spectroscope (EDX). The effect of milling procedures on the mechanical properties such as tensile strength, stiffness, and hardness of prepared nanocomposites was also determined. This technique has shown that calcium carbonate nanoparticles can be produced at low cost, with low agglomeration, uniformity of crystal morphology, and structure from Achatina fulica shell. It also proved that the solvents used for milling have no adverse effect on the chemical properties of the nano-CaCO3 produced. The loading of calcium carbonate nanoparticles, wet milled with different solvents, exhibited different mechanical properties, and nanocomposites filled with methanol-milled nano-CaCO3 offered superior mechanical properties. [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]

Epoxy-based adhesives are widely used for repairing or jointing the metal sheets in the industry. Because of their superior mechanical properties, the metallic nanoparticles can be selected as the additive of the epoxy adhesive. The strength of the Cu nanoparticles (CuNPs) can be expected to improve the mechanical properties of neat epoxy. In this study, CuNPs were added at various weight ratios, such as 1, 2, 5, 10, 15, and 20% into the epoxy resin adhesive. Tensile tests of the dog-bone specimens and the lap-shear tensile tests of the single lap joints were performed for obtaining the mechanical properties. In order to investigate the failure mechanisms, the fractured surfaces of the tensile test samples and adhesively joined sheets were imaged by using a Scanning Electron Microscope. The thermal properties of the adhesives were obtained by using Thermo Gravimetric Analysis and Differential Thermal Analysis. The mechanical and thermal properties of epoxy resin adhesive were improved by adding the CuNPs. The best adding ratios of CuNPs into epoxy were obtained by both mechanical and thermally point of views. As a result of this study, 15 wt% the ratio of Cu nanoparticle adding into the epoxy-based adhesive is suitable for improving the mechanical properties. On the other hand, 20% is the proper Cu nanoparticle adding ratio for the thermal properties improving. [ABSTRACT FROM AUTHOR]

The possibility of obtaining calcium carbonate nanoparticles from Achatina fulica shell through mechanochemical synthesis to be used as a modifying filler for polymer materials has been studied. The process of obtaining calcium carbonate nanopowders includes two stages: dry and wet milling processes. At the first stage, the collected shell was dry milled and undergone mechanical sieving to ≤50 μm. The shell particles were wet milled afterward with four different solvents (water, methanol, ethylene glycol, and ethanol) and washed using the decantation method. The particle size and shape were investigated on transmission electron microscopy, and twenty-three particle counts were examined using an iTEM image analyzer. Significantly, nanoparticle sizes ranging from 11.56 to 180.06 nm of calcium carbonate was achieved after the dry and wet milling processes. The size particles collected vary with the different solvents used, and calcium carbonate synthesis with ethanol offered the smallest organic particle size with the average size ranging within 13.48-42.90 nm. The effect of the solvent on the chemical characteristics such as the functional group, elemental composition, and carbonate ion of calcium carbonate nanopowders obtained from Achatina fulica shell was investigated. The chemical characterization was analyzed using Fourier transform infrared (FTIR) and a scanning electron microscope (SEM) equipped with an energy-dispersive spectroscope (EDX). The effect of milling procedures on the mechanical properties such as tensile strength, stiffness, and hardness of prepared nanocomposites was also determined. This technique has shown that calcium carbonate nanoparticles can be produced at low cost, with low agglomeration, uniformity of crystal morphology, and structure from Achatina fulica shell. It also proved that the solvents used for milling have no adverse effect on the chemical properties of the nano-CaCO3 produced. The loading of calcium carbonate nanoparticles, wet milled with different solvents, exhibited different mechanical properties, and nanocomposites filled with methanol-milled nano-CaCO3 offered superior mechanical properties. [ABSTRACT FROM AUTHOR]

Background: Selenium is an essential trace element which is of fundamental importance to human health. Compared to organic and inorganic selenium, selenium nanoparticles (SeNPs) display unique biological and physicochemical properties. Objectives: In this study, we aimed to optimize the extraction parameters of polysaccharides of Grateloupia filicina (GFPs) and investigate the antioxidant activity of SeNPs stabilized by GFPs. Materials and Methods: GFPs were extracted using hot water. The extraction parameters were optimized by performing an orthogonal experiment. SeNPs were prepared under mild conditions using GFP as the modifier and the stabilizer. A scanning electron microscope (SEM) was used to characterize the prepared GFPs-SeNPs. The antioxidant activities of GFPs, SeNPs, and GFPs-SeNPs were compared by measuring 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, hydroxyl radical scavenging activity, superoxide anion radical scavenging activity, and via reducing power assay. Results: The optimal conditions for the extraction were determined as follows: extraction time 5 h, extraction temperature 90°C, and the ratio of water to raw material 100 mL/g. Under these conditions, the yield of GFPs was 50.34% ±0.27%. GFP-decorated SeNPs with an average diameter of 100 nm were synthesized. GFPs-SeNPs showed a higher antioxidant activity compared to GFPs and SeNPs alone. Conclusion: Hot water extraction was found to be efficient in the process of extraction of polysaccharides of G. filicina. GFPs can significantly enhance the antioxidant activity of SeNPs as modifier and stabilizer. GFPs-SeNPs is an efficient radical scavenger and may be explored as a novel antioxidant agent for use in the fields of foodstuff and medicine. [ABSTRACT FROM AUTHOR]

This work is a critical preventive study for providing a healthy life and enhancing people's safety at work in which introduces of highly efficient and durable UV-protection and antibacterial textiles. With this aim, ZnO nanoparticles are in situ synthesized on the modified cotton fabric to produce the multifunctional fabrics. Herein, the cotton fabric is oxidized by periodate and then treated by 4-aminobenzoic acid ligand (PABA). The modified cotton fabrics are characterized via X-ray powder diffraction, Fourier-transform infrared spectroscopy-attenuated total reflectance, scanning electron microscope, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Moreover, the anti-bacterial, UV-protection, hydrophilicity, and mechanical properties of samples are investigated. The results show that pre-oxidization cotton fabric provides better active sites for the treatment with PABA. Then, PABA treatment provides significant sites for the growth of the ZnO nanoparticles and maintains cross-linking property between oxidized cellulosic fibers and the ZnO nanoparticles which improves the formation and durability of ZnO nanoparticles. The simultaneous sample treatment with ZnO and PABA had synergistic effects on UV protection, stability, and mechanical properties. Moreover, the ZnO PABA oxidized cotton fabrics show excellent UV-protection and significant antibacterial efficacy after 20 washing cycles and 100 abrasion cycles, which can be used in advanced protective textiles. [ABSTRACT FROM AUTHOR]

Nanoparticles have been successfully used for immobilization of different enzymes. The enzyme immobilized by nanomaterials has promising application in the biotechnological industry. The β-glucosidase is very important in industrial field. The immobilization of β-glucosidase by nanomaterials increases its activity and reusability. In this work, the β-glucosidase was extracted from fruiting bodies of Agrocybe aegirit and was purified by anion exchange. The β-glucosidase was immobilized by SiO 2 nanoparticles (nano-SiO 2) crosslink with glutaraldehyde (GA). On the other hand, the β-glucosidase firstly immobilized by process adsorption and then crosslink with genipin (GP) which was produced by the hydrolysis of geniposide by β-glucosidase. Then we compared the properties of both immobilized GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase, their immobilization yields were 83.34% and 96.29% respectively. The GA-crosslinked β-glucosidase and free β-glucosidase revealed optimal pH at 6.0. The optimal pH of GP-crosslinked β-glucosidase was ranging between 4.5 and 7.5. The GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase revealed the optimal temperature at 50 °C, 70 °C respectively. For the free β-glucosidase, the optimal temperature was 55 °C. Furthermore, the GA-crosslinked β-glucosidase and GP-crosslinked β-glucosidase were characterized by scanning electron microscope (SEM). The geniposide consumption in the reaction system of GA-crosslinked β-glucosidase was analyzed by high performance liquid chromatography (HPLC). [ABSTRACT FROM AUTHOR]

Green synthesizes of nanoparticles made a curiosity in the field of nanobiotechnology and they have a wide range of application. In this investigation, the leaf extract of Andrographis serpyllifolia was used to synthesis silver nanoparticles as a greener approach. These green silver nanoparticles characterized by UV-Spectrophotometer, Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy-dispersive X-ray spectroscopy (EDX), Transmission Electron Microscope (TEM), Zeta potential and particle size analysis. The silver nanoparticles were of spherical in nature with a minimum of 3.4 nm to a maximum of 71.6 nm with the average size of 24.1 nm. The larvicidal study showed that the AgNPs were highly active against the Culex quinquefasciatus larvae and the LC50 value observed was 68.889 µg/ml and LC90 value observed was 392.117. In addition, the antimicrobial study revealed that the A. serpyllifolia intervened AgNPs have shown prominent activity against the clinical pathogens viz., Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas fluorescens, and Escherichia coli. The maximum zone of inhibition observed against the S. pneumoniae was 21.33 ± 0.88 mm (75 µg/ml). Whereas, the lowest was observed against the S. aureus 14.66 ± 0.57 mm (25 µg/ml). The A. serpyllifolia mediated AgNPs demonstrated prominent bioactivity and used to control the emerging mosquito population and pathogenic microorganisms. [ABSTRACT FROM AUTHOR]

This study describes the hydrothermal synthesis of cupric oxide nanoparticles (CuO NPs) using Mint extract agent. A mixture of 0.1 M copper nitrate and a mint extract was hydrothermally treated at a temperature of 180 °C for two hours. Meanwhile, the Mint leaf extract had reduced the copper ions of the nanoparticles after five minutes, resulting in dark-green precipitation. The structural and optical properties of the nanoparticles were studied using X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and UV-Vis spectroscopy. The nanoparticles showed a simple cubic structure with a crystallite size range of 22 nm ‒ 25 nm. According to the UV-Vis spectrum, an absorption peak was observed at 346 nm. The antibacterial activity was checked against Escherichia coli (E-coli) and Bacillus subtilis (B-subtilis) cultures by which the inhibition zones were found to be 35 mm and 38 mm, respectively. It is concluded that the CuO NPs have a good ability to resist microbes. [ABSTRACT FROM AUTHOR]

In this study, the sol-gel process has been adopted for the synthesis of Cu1-xAlxO nanostructures (0≤ x ≤ 0.90, in steps of 0.10). The system revealed pure CuO phase with monoclinic structure. Al2O3 phase and copper oxide (Cu2O) were developed at higher substituent concentrations till x=0.40. Structural properties were studied by X-ray diffraction (XRD) and morphological properties by Scanning Electron Microscope (SEM). Average crystallite size from the range of 12.65 nm to 22.9 nm was calculated by Scherer formula. The SEM images indicated that the Cu1-xAlxO possessed nanoparticles like structure, i.e. it contained some pores or voids and vacancies caused by a difference in experimental conditions. Results of EDX revealed the presence of Aluminum (Al), oxygen (O) and copper (Cu) elements in Cu1-xAlxO and the data showed that the nanoparticles were nearly stoichiometric. [ABSTRACT FROM AUTHOR]

Pure SnO2 and doped SnO2 nanoparticles with 2 wt.% ruthenium, 2 wt.% vanadium, and 2 wt.% antimony were synthesized via sol–gel and coprecipitation methods. The obtained doped and undoped dried powders after calcination treatment at different temperatures (973–1223 K) were studied. The structural and morphological characterization of the prepared samples was performed by X-ray powder diffraction (XRD), scanning electron microscope (SEM), differential thermal/thermogravimetric analysis (DTA-TG), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectrum (XPS) and particle size distribution analysis. The effect of structural and morphological properties of the highly additive doped elements nanocrystalline SnO2 powders was discussed. The resulting particles were crystalline oxide particles in the nanometric range (8–31 nm). It was found that the amount of additive played important roles in the particle size effect of nanocrystalline SnO2. Particle size distribution of antimony-doped SnO2 are finer and narrower, and that of vanadium-doped, ruthenium-doped, and undoped SnO2 nanocrystallines are comparatively larger and broader in size distribution. [ABSTRACT FROM AUTHOR]

Alumina nanoparticles are among important metal oxides with specific properties but chemically incompatible with an organic matrix such as poly(methyl methacrylate) (PMMA). In this research, in situ polymerization of methyl methacrylate was performed on alumina nanoparticles to improve the interaction of the nanoparticles and PMMA. These modified nanoparticles were applied as effective additives with appropriate dispersion in the polymer matrix. Different samples were produced using an injection molding process in order to compare the mechanical properties of nanocomposites containing modified and unmodified nanoparticles. X-ray diffraction and scanning electron microscope tests were performed to investigate the effect of modification process on the dispersion quality of nanoparticles into the PMMA matrix. The results indicated that the modified alumina nanoparticles had a better dispersion and interaction in comparison with unmodified alumina nanoparticles due to the modification procedure. Taguchi approach was implemented for the design of experiments and optimization of input parameters. The MCDM methods were also used to select the best experiment according to the different material and process parameters. Impact and tensile strength of samples with 2 wt% of modified alumina nanoparticles were 22.5% and 21.5% better than a sample with the same unmodified alumina nanoparticles content, respectively. [ABSTRACT FROM AUTHOR]

This study describes the hydrothermal synthesis of cupric oxide nanoparticles (CuO NPs) using Mint extract agent. A mixture of 0.1 M copper nitrate and a mint extract was hydrothermally treated at a temperature of 180 °C for two hours. Meanwhile, the Mint leaf extract had reduced the copper ions of the nanoparticles after five minutes, resulting in dark-green precipitation. The structural and optical properties of the nanoparticles were studied using X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and UV-Vis spectroscopy. The nanoparticles showed a simple cubic structure with a crystallite size range of 22 nm ‒ 25 nm. According to the UV-Vis spectrum, an absorption peak was observed at 346 nm. The antibacterial activity was checked against Escherichia coli (E-coli) and Bacillus subtilis (B-subtilis) cultures by which the inhibition zones were found to be 35 mm and 38 mm, respectively. It is concluded that the CuO NPs have a good ability to resist microbes. [ABSTRACT FROM AUTHOR]

In this study, positively charged polystyrene-co-poly (ar-vinylbenzyl) trimethylammonium nanoparticles loading with Aggregation Induced Emission (AIE) fluorescent molecule sulfonated 9,10-distyrylanthracene derivatives (SDSA) by coulomb force denoted as SDSA/PS-co-PVBTAC have been prepared. The size, size distribution and morphology of nanoparticles have been tested by Dynamic light scattering (DLS) and Scanning electron microscope (SEM). The synthesized nanoparticles possess uniform size, good monodispersity and low biological toxicity. The AIE-type SDSA/PS-co-PVBTAC showed good fluorescence stability at pH from 3 to 10. It has been proved that the biological macromolecules including Bovine Serum Albumin (BSA), DNA and RNA can amplify the cell imaging signals. Moreover, the AIE-type nanoparticles have been shown to perform fluorescent imaging of various cells. It suggests that the prepared SDSA/PS-co-PVBTAC can be used as a new biological probe in the field of cell imaging and detection, as well as expanding the application of AIE fluorescent molecules in biosensing field. Through Coulomb force of nanoparticles with AIE fluorophore SDSA, hybrid polymeric nanoparticles SDSA/PS-co-PVBTAC for various cells imaging were prepared. It has been proven that the biological macromolecules can amplify the fluorescence signals, accompanied with good fluorescence stability at pH from 3 to 10. The electrostatic attraction between the positively charged nanoparticles and the negatively charged cell membrane is conducive to improve the cellular uptake of nanoparticle, as well as the effect of intracellular imaging. [ABSTRACT FROM AUTHOR]

A novel primary cell based on graphene and Multi-walled carbon nanotube (MWCNT) as embedded materials have been developed with Al/Al 2 O 3 /Activated carbon (AC) as a matrix. The performances of the cells are quite interesting evidenced by the results of electrochemical studies. There is no formation of dendrite growth of Al which is demonstrated through TEM and SEM studies. The longer life of the cell is acclaimed due to the formation of the flake-like structure of graphene and resistivity towards the crystallinity of graphene layers. The corrosion resistance of Al/Al 2 O 3 and graphene intercalated systems is found high. The resultant graphene-based cell exhibited 1.68 V and assembly of each of 2 such cells yielded 3.36 V which is equivalent to Li-Ion batteries. [ABSTRACT FROM AUTHOR]

Naringenin (NaR) is a flavonoid, mostly found in citrus fruit. Its IUPAC name is 5,7-Dihydroxy- 2-(4-hydroxyphenyl)chroman-4-one. Naringenin is lipophilic in nature and possessing antioxidant property. In present study,7-Dihydroxy-2-(4-hydroxyphenyl)chroman-4-one was incorporated onto CuO nanoparticles (CuO-NPs) for enhancing its antioxidant activity. The CuO-NPs and its functionalized form (CuO-NaR) were characterized by Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), Scanning electron microscope (SEM) and Energy dispersive X-ray (EDX) analysis. The CuO-NPs, CuO-NaR and NaR were examined for their comparative antioxidant activities followed by DPPH (2,2-Diphenyl-1-picrylhydrazyl) method. The results revealed that the antioxidant activity of CuO-NaR was enhanced significantly. [ABSTRACT FROM AUTHOR]

In this study, we report, for the first time, on synthesis of lanthanum oxide La 2 O 3 nanoparticles NPs by laser ablation in water without using surfactant. The effect of laser wavelength on the optical and structural properties of La 2 O 3 NPs was investigated. X-ray diffraction studies show formation of polycrystalline lanthanum oxide with pure cubic phase and the crystallinity of the nanoparticles synthesized with λ = 5 3 2  nm was better than that prepared with λ = 1 0 6 4  nm. The optical absorption investigations reveal that a strong absorption peak at 234 nm was observed for La 2 O 3 NPs prepared at 532 nm laser wavelength. The optical energy gap of La 2 O 3 NPs synthesized with 532 and 1064 nm laser wavelengths were 5 and 4.5 eV, respectively. Scanning electron microscope (SEM) investigation indicated the formation of nanoparticles with average particle size of 35 nm for La 2 O 3 prepared with 532 nm and was 75 nm for La 2 O 3 prepared with 1064 nm laser wavelength. The effect of laser wavelength on the optoelectronic properties of hybrid In/p- La 2 O 3 /n-Si photodetector was studied. The responsivity studies of the photodetectors show the presence of two response peaks at 250 and 750 nm. [ABSTRACT FROM AUTHOR]

Iron and cobalt hexacyanoferrates and their analogs (MHCF) have been synthesized as nanomaterials for the fabrication of C/MHCF composite electrodes. We have studied the structural characteristics and elemental composition of the synthesized compounds by X-ray diffraction and energy dispersive X-ray microanalysis using a VEGA II LMU scanning electron microscope equipped with an INCA Energy 450/XT X-ray microanalysis system (X-Act DDD detector). The results demonstrate that the composite electrodes containing 20% MHCF have a better electrochemical performance than does a carbon electrode. The incorporation of sodium into the structure of iron and cobalt hexacyanoferrates ensures the smallest decrease in the specific capacitance of the composite electrodes at high charge–discharge rates and reduces the charge transport resistance. [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]

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]

Co/B co-doped ZnO (Zn 0.93-x Co x B 0.07 O, x = 0.00, 0.01, 0.02, 0.03, 0.04, and 0.05) nanoparticles were synthesized by the hydrothermal method to investigate the effect of cobalt and boron on the structural, microstructural, and optoelectronic properties of ZnO nanoparticles. The X-ray diffraction method was used for the structural analysis and single phases were found for all Co/B co-doped ZnO nanoparticles. Scanning Electron Microscope (SEM) technique was used to determine the surface morphology, particle size, and the shapes of the nanoparticles. The elemental compositions of the nanoparticles were obtained by electron dispersive spectroscopy (EDS). Hexagonal Wurtzite structure was proved by c/a ratios of the ZnCoBO nanoparticles. The Fourier transform infrared (FTIR) studies were performed and explained. The energy band gaps of the samples were calculated and the effects of dopant elements on optical properties were discussed. The maximum band gap occurred for Zn 0.93 B 0.07 O with a band gap energy of E g = 3.26 eV. The refractive index was calculated using the energy band gap with five different models. The grain sizes and the band gap energies fluctuated as the doping ratio increased. The results showed that the refractive index strongly depends on the Co concentration nonlinearly. It was found that doping cobalt increased the Urbach energy value of B-doped ZnO nanoparticles. The increase in E u indicates that the structural disorder and the number of defects in the Zn 0.93-x Co x B 0.07 O structures increased with increasing concentration of Co in the Zn 0.93-x Co x B 0.07 O structures. The highest value of Urbach energy was approximately found in the range of 1259 and 1469 meV for 3% Co. Moreover, for 3% Co the concentration-dependent microstrain (Ɛ) values also reached the maximum, dislocation density δ had also the maximum value. [ABSTRACT FROM AUTHOR]

In this work, atypical zinc oxide nanorods (ZnO NRs) on quartz substrates were successfully synthesized using simple, low-cost, and environmentally friendly hydrothermal method. The ZnO NRs were grown on a pre-seeded seed layer of ZnO nanocrystals using the spin coating process. Gold nanoparticles (Au NPs) were sputtered on the ZnO NRs film. The structure and morphology of the produced nanostructures were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD analysis revealed that the ZnO NRs were single crystalline with hexagonal wurtzite structure grown with preferred orientation of (002). The SEM morphology shows a semi-hierarchical ZnO NRs with an estimated diameter of 200–400 nm and length of 4–5 μm. The optical properties of the ZnO NRs film were investigated using UV-visible spectrophotometers. The obtained bandgap of ZnO film was 3.0 eV. Electrical and thermal properties were also measured. The resistance changes versus temperature variation of ZnO NRs were given a semiconductor behavior. The gas sensor was fabricated based on bare ZnO NRs and Au NPs/ZnO NRs hybrid. The second nanostructure exhibited an enhanced sensor sensitivity toward ethanol gas at an optimized working temperature of 325 °C. [ABSTRACT FROM AUTHOR]

Background: Nanotechnology offers an advantage as a green route for synthesis of metal nanoparticles (NPs) with plant extracts as capping agent. Spondias mombin is a fruit-bearing tree and its leaf extracts have been reported to possess anxiolytic, hypoglycaemic, antiepileptic, antipsychotic, sedative, antioxidant, and antimicrobial properties. The objective of the study is to determine the antibacterial potential of a simple non-toxic product of green synthesis of metallic (Ag, Zn and Cu) nanoparticles using the leaf of Spondias mombin aqueous extracts (SMAE) as a reducing and capping agents of the metal ions. Methodology: Nanoparticles were characterized by UV visible spectrophotometeric analysis, Fourier Transform Infra-Red (FT-IR) spectrophotometer and scanning electron microscope (SEM). Antimicrobial activities of synthesized NPs against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were determined by agar well diffusion technique. Results: The synthesized NPs varied in colour from dark brown to green and appears dominantly spherical, occasionally rod or triangular shaped with size ranging from 65-90 nm. UV spectroscopy absorption spectra of Ag, Zn and Cu NPs had absorbance peak at 267, 262 and 765 nm respectively. FT-IR spectrometry of Zn NP, Cu NP, and SMAE gave wave number ranging from 895.71-3320.67, 747.02-3225.45 and 658.25-3674.49 respectively. FT-IR analysis showed that SMAE acted as reducing and stabilizing agent while the NPs exhibited lower energy absorption band when compared to the plant extract. The NPs demonstrated higher antimicrobial activities against S. aureus than Ps. aeruginosa and E. coli. The antimicrobial activity was higher with copper NP than Ag and Zn NPs, and also higher than SMAE. Conclusion: The result from this study presents an indication for an alternative means for development of novel antimicrobial agents for clinical and biotechnological applications. [ABSTRACT FROM AUTHOR]

7,8-dihydroxyflavone (7,8-DHF), a tyrosine kinase B (TrkB) receptor agonist, can mimick physiological actions of brain-derived neurotrophic factor (BDNF) to attenuate neurogenic disease. However, its use as a functional food, is limited by its low-water solubility, chemical instability, and poor bioavailability. The purpose of this work is to fabricate stable 7,8-DHF loaded zein/lactoferrin (LF) composite nanoparticles (zein/LF-DHF) to overcome these challenges. Results showed that mean particle size of zein/LF nanoparticles was about 74 nm with low polydispersity index (<0.200) and turbidity (<0.300) values. Zein/LF nanoparticles had good stability against pH (3.0–9.0), ionic strengths (0–500 mM NaCl at neutral pH) and long-term storage. Zein/LF nanoparticles showed spherical structures formed by hydrogen bonding and hydrophobic interactions, however, LF changed surface morphology of zein nanoparticles as observed by scanning electron microscope. X-ray diffraction indicated 7,8-DHF was presented in an amorphous state inside zein/LF nanoparticles. Most importantly, zein/LF-DHF had good redispersibility, and increased the encapsulation efficiency, chemical stability, water solubility and bioaccessibility of 7,8-DHF. Collectively, zein/LF nanoparticles are promising delivery systems for 7,8-DHF in functional foods. Unlabelled Image • Lactoferrin (LF) acted as a powerful stabilizer to fabricate zein nanoparticles. • 7,8-Dihydroxyflavone (7,8-DHF) was firstly encapsulated in zein/LF nanoparticles. • Zein/LF-DHF had good redispersibility in water. • Zein/LF-DHF increased encapsulation efficiency and chemical stability of 7,8-DHF. • Zein/LF-DHF enhanced water solubility and bioaccessibility of 7,8-DHF. [ABSTRACT FROM AUTHOR]

Ceria nanoparticles (CeO2 NPs) are generally considered in various functional applications, such as catalysts in fuel cells, sensors, and antioxidant and oxidase-like enzymes in the biological environment. The CeO2 NPs were synthesized using the E. globulus leaf extract-mediated hydrothermal technique. The synthesized NPs were characterized by various analytical instruments including powder X-ray diffractometer (PXRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and dynamic light scattering (DLS) analysis. The XRD results showed an average NPs sizes of 13.7 nm. Cytotoxic study results showed an IC50 value of 45.5 µg/L for A549 and 58.2 µg/L for HCT 116, indicating that CeO2 NPs are more toxic to A549 compared to HCT116 cell lines. The generation of ROS was responsible for its cytotoxic activity against cancer cell lines. Specific surface area (40.96 m2/g) and pore diameter (7.8 nm) were measured using Brunauer-Emmett-Teller (BET) nitrogen adsorption-desorption isotherms. CeO2 NPs with a high surface area were used as photocatalyst in degrading sunset yellow (SY) dye under UV-irradiation and 97.3% of the dye was degraded within 90 min. These results suggest that the synthesized CeO2 NPs could be used as a good photocatalyst as well as a cytotoxic agent against human cancer cell lines. [ABSTRACT FROM AUTHOR]

This study was aimed to biosynthesized silver nanoparticles by Streptococcus pyogenes bacteria and its antimicrobial activity against (S.aureus ,P. aeruginosa, E.coli, and C. albicans yeast) at different concentrations (20, 40, 60 ,80 and 100) μg/ml by agar well diffusion assay. Fifty sample was collected from Wounds and burns, from Baghdad Teaching City Medicine Laboratories. Samples identified by culture, VITEK 2 Compact system ID-YST kit. The sensitivity of bacterial isolates to antibiotics ware tested and the microbes were more sensitive, resistant and moderate range to antibiotics. Several techniques where used to characterize AgNPs: X-ray Diffraction (XRD), UV–Visible Spectroscopy(UV) and Scanning electron microscope (SEM).The results show that biosynthesized silver nanoparticles are more effective than bacterial supernatant on human pathogenic microbes. [ABSTRACT FROM AUTHOR]

A new type of reverse osmosis (RO) membrane incorporating S‐Beta zeolite nanoparticles was synthesized through interfacial polymerization of m‐phenylenediamine and trimesoyl chloride on the surface of nanoporous membrane support. The presence of S‐Beta zeolite in the polyamide layer of RO membrane was detected by scanning electron microscope equipped with energy dispersive X‐ray spectroscope. The impacts of S‐Beta zeolite loading ranging from 0.01 to 0.1 wt% on the separation performance of membrane were further studied and the results showed that the optimal S‐Beta zeolite for RO membrane was at 0.05 wt%. Compared to the control RO membrane without nanoparticles that showed water flux of 25.36 L/(m2.h) and NaCl rejection of 97%, the membrane incorporated with optimal zeolite loading exhibited better performance (65.25 L/(m2.h) and 97.33%) when tested using 1500 ppm NaCl solution at 300 psi. [ABSTRACT FROM AUTHOR]

The nanoparticles are emerging as the new technology in the area of machining and also a substitute for conventional machining fluids. The article illustrates the effect of minimum quantity lubrication technique using copper nanofluids in drilling on AA 5052 alloy. The experiments were performed under dry machining, oil machining and nanofluids under MQL by varying the cutting speed. Surface roughness (Ra), tool wear, cutting temperature and chip morphology are the responses considered for the study. It was observed that use of copper nanofluid under MQL paved a way in reducing the surface roughness by 92 and 76%, tool wear reduced by 36 and 24% and cutting temperature decreased by and 27% compared to dry and oil lubrication. In addition, the three-dimensional view of surfaces machined was analysed by atomic force microscope (AFM) and tool wear, chip morphology were examined under scanning electron microscope (SEM) to analyse the texture generated. [ABSTRACT FROM AUTHOR]