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Plant-mediated processes offer a more straightforward and cost-effective alternative to conventional chemical and physical methods for the reduction of silver ions to silver metallic nanoparticles. This study was conducted to synthesize silver nanoparticles (AgNPs) using a solution of silver nitrate (AgNO3) and a local Basciftlik white potato cultivar (S. tuberosum). Furthermore, the study aimed to compare antioxidant activity of nano-silver particles with that of the potato extract. The potato cultivar was extracted with deionized water and the solution was filtrated. The filtrate was reacted with AgNO3 solution to obtain the AgNPs. The structure of synthesized AgNPs was determined by a spectroscopic study, and characteristic functional groups were analyzed by a fourier-transform infrared spectroscopy (FTIR). The signal observed at 3267 cm−1 is indicative of the hydroxyl functional group. The highest absorption at 429 nm in ultraviolet-visible (UV-VIS) spectrum confirmed the occurrence of the synthesized AgNPs. The biogenic crystalline structure of the synthesized AgNPs was verified by an X-ray diffraction analysis. Average size and morphology of the St-AgNPs were determined by Scanning Electron Microscope analysis, which also indicated the formation of the AgNPs with an average size of 37.31 nm. Antioxidant activity study revealed that the synthesized AgNPs had higher antioxidant activity compared to that of the potato extract alone. [ABSTRACT FROM AUTHOR]

Nanofluids have demonstrated incredible potential for application in various industries such as coolants. Metal oxides are widely used as solid particles in formulations of nanofluids due to their advantages. Metal oxide-based nanoparticles (NPs), ZnO NPs were fabricated by the ultrasonically assisted co-precipitation method. The structure and morphology of the synthesized ZnO NPs were characterized using an array of analytical techniques including X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The XRD results showed that the purity of ZnO was obtained. The investigated nanofluids remained stable for a long time without substantial sedimentation. The present study deals with the corrosion assessment of St37 steel in nanofluids prepared with various concentrations of ZnO NPs. A scanning electron microscope coupled with energy-dispersive X-ray spectroscopy was used to determine the surface characteristics and elemental composition of low-carbon steel specimens both before and after corrosion tests. Notably, the nanofluid containing 0.05% by weight of ZnO nanoparticles demonstrated the highest corrosion prevention efficiency among the prepared nanofluids. Furthermore, impedance spectroscopy measurements revealed that the corrosion resistance increased by 72.9% for the nanofluid containing 0.05 wt% ZnO NPs compared to the base fluid. These findings highlight the potential of ZnO nanoparticles as an environmentally friendly anti-corrosion compound in cooling systems, effectively reducing corrosion degradation. [ABSTRACT FROM AUTHOR]

This paper focuses on the evaluation of the strength development and microstructure of nano-calcium carbonate (CaCO3) cemented paste backfill experimentally cured under isothermal conditions at room temperature and non-isothermal conditions in the field. A series of mechanical (uniaxial compressive strength, UCS) and microstructural (thermogravimetric, mercury intrusion porosimetry, scanning electron microscope) tests as well as monitoring experiments are experimentally conducted on cemented paste backfill (CPB) specimens with and without nano-calcium carbonate and cured at different times and under isothermal or non-isothermal conditions. The results show that the addition of nano-CaCO3 particles to CPB significantly improves its mechanical strength, irrespective of the thermal curing conditions (isothermal, field non-isothermal conditions). However, the impact of nano-CaCO3 particles on the increase in strength of CPB is only effective or significant at the early ages (curing time≤7 days). It is also found that the higher temperatures improve the accelerating effect of nano-CaCO3 much more than they accelerate the PCI hydration reactions in the first 3 days. Moreover, it is also found the sulphate ions present in the natural gold tailings negatively affect the mechanical performance of nano-CPB and reduced the accelerating effect of nano-CaCO3 due to sulphate attacks. [ABSTRACT FROM AUTHOR]

Natural leather still represents great importance among the materials used by humans in modern times, although it is the oldest-known fiber used by humans. Adding new features to the leather, such as bacteria and fungi resistance, electrical conductivity and magnetic properties, is an ambitious goal for leather developers. In our study, production and characterization of anti-microbial sole leather coated with zinc oxide nanoparticles were achieved. For this purpose, the ZnONPs have been prepared through green synthesis and the prepared nanomaterial loaded on the sole leather by a padding mangle. The surface morphology of the nano coated sole leather was studied using a scanning electron microscope (SEM). Antimicrobial performance of the treated leather to some microorganisms was evaluated by applying the qualitative agar disc diffusion method. The SEM image of the treated leather samples showed successive leather coating, and the nanoparticles completely adhere to the leather surface. The nano-treated leather samples showed significant resistance to the tested bacteria and fungi. Results are promising for the utilization of zinc oxide nanoparticles as additives for sole leather coating. Accordingly, the study succeeded in producing a natural microorganism-resistant sole leather, which can be used in the production of healthy and microorganisms-resistant shoes. [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]

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]

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]

In this study, triazoloquinazolinone and benzimidazoquinazolinone derivatives have been synthesized via a suitable and efficient procedure using one-pot multicomponent reactions of 3-amino-1,2,4-triazole or 2-aminobenzimidazole, dimedone and aromatic aldehydes in the presence of TiO2@ILs as an efficient nanocatalyst. In the presented approach all of the products were prepared with good to excellent yields using TiO2@ILs nanostructures. Moreover, the TiO2 NPs were prepared using beet juice extract and functionalized with ILs based on imidazole. TiO2@ILs nanocatalyst has been characterized by different techniques such as Fourier transforms infrared, thermogravimetric analysis, X-ray diffraction, scanning electron microscope and energy-dispersive X-ray spectroscopy. Moreover, this ionic liquid presented itself as a good protective and activator agent for nanocatalyst. [ABSTRACT FROM AUTHOR]

Repaglinide (RPG, antidiabetic) and Diltiazem HCL (DIL, antihypertensive) loaded ethyl cellulose (EC) nanoparticles were prepared by the spray drying process using Placket Burman Design (PBD). The amount of EC (A, mg), Methanol (B, ml), Inlet temperature (C, OC), Feed rate (D, rpm), Nozzle diameter (E, mm) and Aspiration (F, rpm) were considered independent variables while EE of RPG (Y1) and EE of DIL (Y2) were selected as dependent variables. The optimized DIL and RPG loaded EC nanoparticles were further used for the development of oral fast disintegrating sustained release tablets by direct compression method. The tablets were evaluated for weight variation, thickness, hardness, disintegration time, friability and dissolution test. FTIR study showed no chemical interaction between drug and polymer. Scanning electron microscope showed spherical as well as oval shape and discrete nature of both nanoparticles. The physical parameters of oral fast disintegrating tablets developed with optimized formulation of drug loaded nanoparticles were found within the range. Drug loaded nanoparticles as well as oral fast disintegrating tablets showed very good sustained release behavior. [ABSTRACT FROM AUTHOR]

A green and efficient method for the synthesis of chromene derivatives using TiO2 doped Ag as a photocatalyst under visible light irradiation at room temperature is reported. The advantages of our method are clean reaction condition, easy workup procedure, use of eco-friendly solvent, and recyclable catalyst and most importantly higher yield of the product. The photocatalyst was found to be highly efficient for the synthesis of chromene derivatives within a short reaction time. The photocatalyst was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), and powder XRD technique and thermogravimetric analysis (TGA). In addition, the in-vitro study of helminths against S. obvelata were investigated and it was found that chromene derivatives were active against S. obvelata and showed no sign of acute toxicity in mice. [ABSTRACT FROM AUTHOR]

In the present work, Ni0.6Cd0.4DyxFe2-xO4 (x = 0.0, 0.05, 0.10, 0.15, 0.20) nanoparticles (NPs) were synthesized by using sol–gel method. X-ray diffraction (XRD) patterns confirmed that the pure and dysprosium substituted Ni–Cd ferrites are in single-phase spinel structures, while a trace of DyFeO3 appears as a minor phase for higher concentrations (x = 0.10, 0.15 and 0.20). The Debye–Scherrer's method and Williamson–Hall (W-H) method were used to evaluate the crystallite sizes and lattice strain. Scanning electron microscope (SEM) images show that reduction of grain size with Dy3+ content. Elemental composition features of samples were examined by Energy-dispersive X-ray spectroscopy (EDS). The average particles size estimated from transmission electron microscopy (TEM) analysis is in good agreement with results obtained from XRD. The results showed that saturation magnetization (Ms) decreases and coercivity (Hc) increases with an increase in Dy3+ concentrations. The dielectric constant was found to decrease with increasing Dy content in Ni–Cd ferrites. [ABSTRACT FROM AUTHOR]

In this work, the hybrid WO3/titanium dioxide (TiO2) photocatalysts were prepared using hydrothermal method for the degradation of methylene blue dye under visible light irradiation. The scanning electron microscope, Fourier transform infrared spectroscopy, ultra violet visible absorption and photoluminescence emission spectroscopy were employed to study the morphology, structure and functional groups, elemental composition and purity, and optical properties. The morphological results showed the rectangular structure of pure WO3 with size of 36–550 nm, whereas spherical structures were also observed after incorporation of TiO2 in WO3. The monoclinic phase was found with high crystallinity. The composite sample (2% TiO2/WO3) showed seven times improved photocatalytic activity as compared to pure samples. The improvement may attribute to the increase of the photo-absorption effect by the TiO2, the cooperative effect of the WO3, optimal band gap and unique morphological structures. Considering our present study as cost-effective method, the as-synthesised photocatalysts can be suitable and give a new perspective for applied use in energy and environmental applications. [ABSTRACT FROM AUTHOR]

The aim of the present study is to use microwave sintering technique to fabricate Al-Graphene oxide (Al-GO) composites with different concentration of GO (i.e. 0.5 wt %, 1 wt%, and 2 wt%) at 600°C for 15 min. X-ray diffraction (XRD) and scanning electron microscope (SEM) were utilized to investigate the microstructural development. Uniform dispersion of GO was obtained in Al-0.5GO composite whereas other concentration of Al-GO composites suffered from agglomeration of GO particles. In addition to microstructure, the hardness, compressive strength, and corrosion resistance of the Al-GO composites were also examined. A remarkable improvement in compressive strength (up to 200%) was attained in Al-0.5GO composite while further addition of GO deteriorated the mechanical strength and hardness due to agglomeration and increase of the microporosities. In spite of significant enhancement in compressive strength with optimum amount of GO nanoplatelets (i.e. 0.5%), the corrosion resistance of the Al-GO composites was degraded by the addition of GO nanoplatelets mainly due to the increased amount of microporosities and surface roughness originating from agglomeration of GO nanoplatelets. [ABSTRACT FROM AUTHOR]

Synthesis of titanium dioxide nanoparticles (TiO2 NPs) has been done by sol-gel-hydrothermal colloidal route in two different apparatus; one being simple stainless steel (named as TiO2-B) and other being at constant temperature and pressure autoclave (named as TiO2-W). These TiO2 NPs were investigated by various characterization techniques such as scanning electron microscope (SEM), X-ray diffractometer (XRD), and photoluminescence spectrophotometer. Also, it was observed that the quality of the synthesized TiO2-W NPs is comparable with the commercial TiO2 NPs (TiO2-C), whereas the cost of synthesis is almost reduced to half. The synthesized TiO2 NPs are used as the photoanode in dye-sensitized solar cell (DSSC). DSSC with TiO2-W showed better power conversion efficiency as compared to DSSC with TiO2-B. [ABSTRACT FROM AUTHOR]

In this study, oleuropein was isolated from olive leaves by chromatographic method and its structure was elucidated by spectroscopic analyses such as FTIR, 1H-NMR and 13CNMR. Silver nanoparticles (AgNPs) were synthesized using oleuropein and their antioxidant activity was investigated using DPPH, ABTS•+, and FRAP assays. The AgNPs were characterized by UV-Vis, FT-IR, XRD, and SEM analyses. The absorption peak at 450 nm in UV-Vis spectrum confirmed the AgNPs formation. Scanning electron microscope (SEM) identified the formation of spherical-shaped nanoparticles with the average size of 71 nm. Rietveld analysis was carried out by X-ray diffraction data with High Score Plus software. XRD with 2θ degrees at 38.1°, 44.3°, 64.4° and 77.4° can be assigned to the (111), (200), (220) and (311) Bragg's reflections of the face-centered cubic crystalline structure. Biosynthetic nanoparticles revealed more inhibitory effect (5.22, IC50, µg/mL) against ABTS•+ than standard BHT (7.03, IC50, µg/mL). [ABSTRACT FROM AUTHOR]

The chitosan-grafted-poly(N-vinylcaprolactam) copolymer was synthesized via the free radical polymerization and the electrospun nanofibers were prepared via electrospinning method. The nanofibers surface was coated with gold-gold sulfide nanoparticles and the cisplatin anticancer drug was loaded into the nanofibers for controlled release of cisplatin and the treatment of MCF-7 breast cancer cells. The synthesized gold nanoparticles were characterized using transmission electron microscopy, energy dispersive X-ray and ultraviolet–visible spectroscopy analysis. The characteristics of nanofibers were determined using Fourier-transform infrared spectroscopy, scanning electron microscope and dynamic light scattering analysis. The drug loading efficiency and cisplatin release profiles from synthesized nanofibers were evaluated. [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]

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]

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]

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]

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]

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]

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]

A new molecular precursor Ca[SbO(SCH2COO)Cl H2O] was synthesized from the reaction of calcium thioacetate with SbCl3 in (1:1) ratio. The precursor was characterized by elemental analyses, infrared spectra (IR), and thermal analyses (TGA). IR spectra indicated that thioacetate chelates Sb in a binegative bidentate manner via thiol sulfur and carboxylate oxygen after deprotonation. TGA results indicated that the precursor decomposes in three steps. Calcium antimonate (CaSb2O6) was synthesized from the thermal decomposition of the molecular precursor at 250 °C in air. The calcination product was characterized by X-ray diffractions (XRD), scanning electron microscope (SEM), and transmittance electron microscope (TEM). The results of X-ray diffractions indicated the formation of calcium antimonate nanoparticles which crystallizes in hexagonal system. The crystallite size was found to be 32 nm. Electron microscopes (SEM and TEM) indicated the formation of aggregates of spherical nanoparticles that forms rod like shape. The optical band gap (Eg) measurements showed allowed direct electronic transition. The determined Eg value is 3.9 eV, which is larger than the bulk. [ABSTRACT FROM AUTHOR]

The chitosan/gelatin hydrogel incorporated with biphasic calcium phosphate nanoparticles (BCP-NPs) as scaffold (CGB) for bone tissue engineering was reported in this article. Such nanocomposite hydrogels were fabricated by using cycled freeze-thawing method, of which physicochemical and biological properties were regulated by adjusting the weight ratio of chitosan/gelatin/BCP-NPs. The needle-like BCP-NPs were dispersed into composites uniformly, and physically cross-linked with chitosan and gelatin, which were identified via Scanning Electron Microscope (SEM) images and Fourier Transform Infrared Spectroscopy (FT-IR) analysis. The porosity, equilibrium swelling ratio, and compressive strength of CGB scaffolds were mainly influenced by the BCP-NPs concentration. In vitro degradation analysis in simulated body fluids (SBF) displayed that CGB scaffolds were degraded up to at least 30 wt% in one month. Also, CCK-8 analysis confirmed that the prepared scaffolds had a good cytocompatibility through in culturing with bone marrow mesenchymal stem cells (BMSCs). Finally, In vivo animal experiments revealed that new bone tissue was observed inside the scaffolds, and gradually increased with increasing months, when implanted CGB scaffolds into large necrotic lesions of rabbit femoral head. The above results suggested that prepared CGB nanocomposites had the potential to be applied in bone tissue engineering. [ABSTRACT FROM AUTHOR]

Fluocinolone acetonide (FA), a glucocorticoid is used to treat inflammation in the posterior segment of the eye. Due to short half-life and body clearance, it will not be able to give therapeutic effect for long time with a single injection. Formulating FA nanoparticles (NPs) or PEG conjugates can be an effective way to overcome these disadvantages. We prepared two formulations, FA loaded in PLGA nanoparticles (NPs-FA) and FA conjugated to linear PEG (PEG-FA). The NPs-FA were characterised for size and zeta potential using particle size analyser and shape and morphology by using scanning electron microscope (SEM). The amount of drug loaded per mg of NPs and in-vitro release of FA from NPs were calculated using reverse phase high pressure liquid chromatography (RP-HPLC). NPs synthesis was optimized with factorial and Response Surface Methodology (RSM). Chemically synthesized PEG-FA conjugates were characterized using H-NMR and purity of the conjugate was analysed using RP-HPLC. Visualization of cellular uptake of NPs was done by coumarin-6 loaded NPs under fluorescent microscope. RAW 264.7 macrophages were treated with NPs-FA and PEG-FA conjugates to study their effectiveness in inhibiting TNF-α levels compared to free FA treatment. Stability test confirmed that FA is more stable within NPs than in free form. Particle size and zeta potential were found to be 183.6 ± 12.47nm and −25.6 ± 4.4mV, respectively. 149.58 ± 11.3µg of FA was encapsulated per mg of NPs and 61 µg of FA was present per mg of PEG-FA conjugate. In vitro drug release study showed a sustained release of FA from the NPs for a period of 30 days. Fluorescent microscope images showed uptake of NPs by RAW 264.7 cells. TNF-α assay confirmed that substantial inhibition of TNF-α levels from both formulations compared to free FA. From the results, we conclude that new formulations will greatly reduce drug dosage and frequency of administration for long term treatment of inflammation in posterior part of the eye. [ABSTRACT FROM AUTHOR]

Nanoparticles of regioregular poly(3-hexylthiophene) (P3HT) with different molecular weights were prepared by reprecipitation method. Particle sizes of the nanoparticles were estimated approximately 30 nm by dinamic light scattering measurement and field effect scanning electron microscope observation. The nanoparticle dispersions exhibited thermochromic behaviors. Absorption bands corresponding to the P3HT crystalline phase were observed at 25 °C. As temperature increased, the bands ascribed to the crystalline phase were decreased and those due to the amorphous phase increased. The spectra of the nanoparticle dispersions at 95 °C were almost the same as those in the solution state. By comparing to areas of absorption spectra corresponding to the crystalline and amorphous phase, it was found that the crystallinity of the nanoparticles was strongly dependent on the molecular weight. [ABSTRACT FROM AUTHOR]

Human serum albumin (HSA) is a major blood plasma protein also found in urine where its existence may be a marker of some types of liver or kidney dysfunction. Herein, we fabricated a novel surface plasmon resonance (SPR) nanosensor for selective, sensitive, and label-free microalbumin detection both in aqueous and urine sample solutions. First, HSA-imprinted nanoparticles were synthesized, which consist of ethylene glycol dimethacrylate and N-methacryloyl-L-leucine methyl ester as a cross-linker and functional monomer. The nanoparticles were characterized by zeta-size and scanning electron microscope analyses and were dropped onto the SPR chip surface to make HSA sensitive nanosensor. Characterization studies of HSA-imprinted SPR chip were carried out by atomic force microscopy, Fourier-transform infrared spectroscopy, contact angle, and ellipsometer. The limit of detection and limit of quantification values of HSA-imprinted SPR nanosensor were calculated as 0.7 pM and 1.9 pM for the concentration range of 0.15–500 nM. Selectivity studies of HSA-imprinted SPR nanosensor were achieved with hemoglobin and transferrin proteins which were chosen as competitor molecules. HSA-imprinted SPR nanosensor was displayed highly selective and sensitive to HSA. [ABSTRACT FROM AUTHOR]

In this study, the photocatalytic degradation of Reactive Blue 81 (RB81) using synthesized NiO-doped ZnO–ZrO2 nanoparticles under UV irradiation was investigated. Then, the products were characterized by Scanning electron microscope (SEM), X-ray diffraction (XRD), and diffuse reflectance spectroscopy (DRS). The removal rate of RB81 using ZnO–ZrO2 after 180 min of irradiation was 96.7%. Nickel oxide (NiO) was used as an additive to ZnO–ZrO2 for improvement of RB81 degradation via photocatalysis process. Photodegradation of RB81 was achieved to 100% using ZnO–ZrO2–NiO nanoparticles with ratio of 1:2:0.3 after 180 min of irradiation. There was a red shift in absorption bands (from 410 nm to 435 nm) observed in increasing of NiO to ZnO–ZrO2 nanoparticle, that it might lead to a higher photocatalytic activity under visible light. Response surface methodology (RSM) was used for optimization of experimental and these results were obtained: solution pH = 3, ZnO–ZrO2–NiO dosage = 15 mg/L, and the initial RB81 concentration = 5 mg/L. The photodegredation of RB81 followed pseudo-first order kinetic according to the Langmuir–Hinshelwood model. [ABSTRACT FROM AUTHOR]

The GO/SnO2 micronanostructure was synthesized by a simple and effective hydrothermal method. The combined characterization methods such as Scanning Electron Microscope (SEM), Transmission electron microscope (TEM), X-ray diffraction (XRD), Element mapping, Energy Dispersive X-Ray Spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), the Raman spectroscopy, the Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), photoluminescence (PL) the Ultraviolet–visible spectroscopy (UV-Vis) and Diffuse reflectance spectrum (DRS) indicated the successful formation of GO/SnO2 micronanostructure. Moreover, the photocatalytic activity tested with RhB aqueous solution revealed that GO/SnO2 had excellent photocatalytic properties compared with SnO2. The photocatalytic efficiency of GO/SnO2 was much higher (about 2.5 times) than that of pure SnO2 under visible light irradiation. Based on these test results, we believe that the present work will provide some thoughts for further fabrication of other novel nanostructures and exploration of their applications. [ABSTRACT FROM AUTHOR]

Palladium, the building block of white gold, has been found to exhibit extraordinary properties in nanotechnological products produced in recent years. The most prominent feature of palladium is adsorbing and storing high levels of hydrogen. Therefore, the demand for palladium in the world increased excessively in the 2000s. In the present study, palladium nanoparticles (PdNPs) were biosynthesized by the extract of Diospyros kaki leaves as bio-stimulator. D. kaki, also called persimmon, was collected in a local area in Istanbul Turkey. PdNP formation was screened by analyzing UV-Vis spectrophotometer at 250-550nm. The nanoparticles were characterized by scanning electron microscope which revealed that the biosynthesized PdNPs were in sizes ranging from 50 to 120 nm. Fourier transform infrared spectroscopy applied on both D. kaki leaf extract and PdNPs was used to decide on the reactive groups managing the reduction of the biosynthesized nanoparticles. Also, the PdNPs showed reasonably proficient antibacterial efficacy for both Escherichia coli and Staphylococcus aureus and the zones of inhibition were found as 18 and 10.5 mm, respectively. [ABSTRACT FROM AUTHOR]

This article deals with the synthesis and characterization of undoped and zinc doped nickel oxide nanoparticles. Prepared nanopowders have been characterized by x-ray diffraction method, high resolution scanning electron microscope, ultraviolet visible spectrometer, photoluminescence spectrometer, Fourier transform infrared spectrometer, impedance meter and thermal gravimetric analyzer. X - ray diffraction study confirmed the average crystallite sizes of the nanopowders are less than 20 nm. Ultraviolet-visible spectrometer recorded the absorption peaks between 336 - 346 nm, corresponds the energy gap of 3.70 - 3.58 eV. Photoluminescence spectrum confirms the near band edge emission. Fourier transform infrared spectroscopy analysis established the formation of the nickel oxide and the doping of zinc. The high resolution scanning electron microscope image depicts that the particles are uniform in size and they are in severe agglomeration. The dielectric studies recognized the decrease in dielectric losses with increasing the temperature as well as frequency. Thermo gravimetric study shows that the prepared samples have good stability. [ABSTRACT FROM AUTHOR]

Migration of fibroblasts into wound area is a critical phenomenon in wound healing process. We used an appropriate system to fabricate an electrospun bioactive scaffold with controlled release of PDGF-BB in order to induce migration of primary skin fibroblast cells. First of all, protein-loaded chitosan nanoparticles based on ionic gelation interaction between chitosan and sodium tripolyphosphate were prepared. Then polycaprolactone electrospun fibers containing chitosan nanoparticles or PDGF-BB-loaded chitosan nanoparticles were prepared. Cellular attachment and morphology of cells seeded on scaffolds with or without PDGF-BB were evaluated by using a fluorescence microscope and scanning electron microscopy. Cells were well-oriented 72 h after seeding on the scaffolds containing PDGF-BB. The mean aspect ratio of populations on scaffold containing PDGF-BB-loaded chitosan nanoparticles was significantly greater than those on the scaffold containing chitosan nanoparticles but no PDGF-BB. Furthermore, the Arp2 gene, which is involved in cell protrusion formation, showed about three times more expression at mRNA level, in cells seeding on PDGF-BB-containing scaffold compared to cells seeding on scaffold containing only chitosan nanoparticles, using Real Time PCR test. Finally, under agarose migration assay results demonstrated that cells' chemotaxic behavior was more toward scaffold containing PDGF-BB compared to the PDGF-BB alone or FBS group. In addition, in terms of distance, the cell mass could grow faster, in response to scaffold containing PDGF-BB compared to FBS or PDGF-BB alone; however, the number of migrating cells might be the same or significantly higher in the latter groups. [ABSTRACT FROM AUTHOR]

In this study chitosan nanoparticles (CS NPs) and mannosylated chitosan nanoparticles (MCH NPs) loaded with recombinant hepatitis B surface antigen (rHBsAg) was synthesized as a vaccine delivery system and assessed toxically and immunologically. The physicochemical properties of the nanoparticles (NPs) were determined by methods including scanning electron microscope (SEM) and dynamic light scattering (DLS). The morphology of the NPs was semi spherical and the average diameter of the loaded CS and MCH NPs was found to be 189 and 239 nm, respectively. The release studies showed that after the initial burst, both of the loaded NPs provided a continuous and slow release of the antigens. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed concentration and time dependent toxicity profile for both formulations, but rHBsAg loaded CS nanoparticle showed higher toxicity due to smaller particle size and larger zeta potential. Abnormal toxicity test (ATT) results showed no signs of toxicity in mice and guinea-pigs treated with loaded MCHNPs. Stability test for six months showed acceptable changes in size, surface charge, and antigenicity for loaded MCH nanoparticles. Finally, in vivo immunogenicity study revealed greater adjuvant capability of MCH nanoparticles than others formulations. Our results showed MCH NPs can be used as a controlled and targeted vaccine delivery system. [ABSTRACT FROM AUTHOR]

This study examined the tribological properties of two lubricating oils, mobil gear 627 and paraffinic mineral oils, with multi-walled carbon nanotubes (MWCNTs) nanoparticles used as additives with various concentrations (0.1, 0.5, 1, and 2 wt.%). The friction and wear experiments were performed using a four ball tribotester. The samples were tested for their anti-wear, load carrying capacity, and friction coefficients according to ASTM D-2783, ASTM D-2596, and ASTM D-5183 standards. The experimental results show that the addition of MWCNTs to base oils exhibit good friction reduction and anti-wear properties. The wear test results show a decreased wear by 68% and 39% in the case of MWCNTs-based mineral oil as compared with base mobil gear 627 and paraffinic mineral oils, respectively. Furthermore, the friction reduction results show a decrease of friction about 57% and 49% in the case of MWCNTs-based mineral oil as compared with base mobil gear 627 and paraffinic mineral oils, respectively. The weld load of the base oil containing 1% MWCNTs was found to be 400 kgf and 125 kgf as compared with base mobil gear 627 and paraffinic mineral oils, respectively, which got welded at 200 kgf and 100 kgf. The morphologies and typical element distribution of the worn surfaces were characterized by scanning electron microscope (SEM) and energy-dispersive X-ray (EDX). The SEM micrographs and EDX chemical analysis confirm the formation of a tribolayer composed of the elements from the nanoparticles. [ABSTRACT FROM AUTHOR]

A series of Pd/BiOCl catalysts have been prepared via a facile ethylene glycol (EG)-assisted solvothermal process in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium chloride ([C16mim]Cl). The as prepared products were characterised by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, transient photocurrent response analysis, UV-vis diffuse reflectance spectra and photoluminescence spectroscopy. During the reaction process, [C16mim]Cl acted not only as Cl source but also as solvent, template and dispersing agent for the fabrication of Pd/BiOCl flower-like microspheres structures. The existence of ionic liquid was beneficial to generate small scale and steady Pd nanoparticles. Moreover, the photocatalytic activities of the Pd/BiOCl composite samples were evaluated by the photocatalytic degradation of rhodamine B. The effects of structure and morphology made by the introduction of Pd have been studied. A possible mechanism of Pd on the enhancement of visible light performance was also proposed. [ABSTRACT FROM AUTHOR]

The paper demonstrates the filling of cobalt nanoparticles into the multiwalled carbon nanotube buckypaper by the dispersion and filtration method to study microwave absorption. Synthesised buckypaper samples were subject to characterisation by using X-ray diffraction, scanning electron microscope, atomic force microscope and four probe techniques to measure the size of the cobalt particles, morphology and low temperature electrical resistivity of the buckypaper, respectively. We used two different sizes of cobalt particles (14·54 and 33·04 nm, respectively) for doping in the buckypaper. Microwave-absorbing properties were examined by measuring the transmission coefficient (S21) in a frequency range of 1-20 GHz with the buckypaper as an absorber. Variations in the resistivity value, with different particle sizes of cobalt were attained by the low temperature resistivity measurements. The observed maximum of S21 indicates that the cobalt-buckypaper displays good microwave absorption (90%) properties for a potential application as wideband electromagnetic wave absorbers. [ABSTRACT FROM AUTHOR]

High-angle annular dark-field scanning transmission electron microscopy (HAADF STEM) in a scanning electron microscope facilitates the acquisition of images with high chemical sensitivity and high resolution. HAADF STEM at low electron energies is particularly suited to image nanoparticles (NPs) in thin cell sections which are not subjected to poststaining procedures as demonstrated by comparison with bright-field TEM. High membrane contrast is achieved and distinction of NPs with different chemical composition is possible at first sight. Low-energy HAADF STEM was applied to systematically study the uptake of Pt-NPs with a broad size distribution in HT29 colon carcinoma cells as a function of incubation time and incubation temperature. The cellular dose was quantified, that is, the amount and number density of NPs taken up by the cells, as well as the particle-size distribution. The results show a strong dependence of the amount of incubated NPs on the exposure time which can be understood by considering size-dependent diffusion and gravitational settling of the NPs in the cell culture medium. [ABSTRACT FROM AUTHOR]

The paper demonstrates the filling of cobalt nanoparticles into the multiwalled carbon nanotube buckypaper by the dispersion and filtration method to study microwave absorption. Synthesised buckypaper samples were subject to characterisation by using X-ray diffraction, scanning electron microscope, atomic force microscope and four probe techniques to measure the size of the cobalt particles, morphology and low temperature electrical resistivity of the buckypaper, respectively. We used two different sizes of cobalt particles (14·54 and 33·04 nm, respectively) for doping in the buckypaper. Microwave-absorbing properties were examined by measuring the transmission coefficient (S21) in a frequency range of 1-20 GHz with the buckypaper as an absorber. Variations in the resistivity value, with different particle sizes of cobalt were attained by the low temperature resistivity measurements. The observed maximum of S21 indicates that the cobalt-buckypaper displays good microwave absorption (90%) properties for a potential application as wideband electromagnetic wave absorbers. [ABSTRACT FROM AUTHOR]

In the present investigation, alginate nanoparticles have been prepared and characterised by various techniques such as FTIR, SEM, particle size analysis and surface charge measurements. It was found from both the SEM and particle size analysis that average size of the particle was about 40 nm. The particles were loaded with insulin and the release kinetics of insulin was studied in PBS medium. The results indicated that when percent loading increases from 11.7 to 38.9, the released amount of insulin increased from 18% to 60% of the loaded drug. The effect of composition of nanoparticles, pH and temperature of the release medium was examined on the amount of released insulin. It was observed when that amount of alginate in the feed mixture was varied from 1.0 to 2.0 g, the prepared nanoparticles showed a decreasing tendency to release insulin. Similarly, upon increasing the concentration of crosslinker in the range 0.5–1.1 mM, the release of insulin constantly decreased. The chemical stability of the loaded drug was assessed especially under highly acidic conditions of artificial gastric juice and it was noticed that even in harsh acidic environment (pH 1.2) the insulin remains chemically stable. Theinvitroblood compatibility of nanoparticles was also investigated and it was found that for a definite composition of nanoparticles, protein adsorption and percent haemolysis were minimum which suggested for an optimum blood compatibility of alginate nanoparticles of definite composition. Thus, it can be conclusively stated that the calcium alginate nanoparticles prepared by emulsion crosslinking method show potential to be developed as oral formulation for insulin delivery. [ABSTRACT FROM AUTHOR]

The composite microwave absorbing coatings reinforced with carbonyl iron nanoparticles were systematically studied. The morphologies of Fe–Si–Al powders (FSA), carbonyl iron nanoparticles (nmCIP) and the corresponding composite coating sections were characterised by scanning electron microscope (SEM) and transmission electron microscope (TEM). The electromagnetic performances of the microwave absorbents mentioned above were measured by vector network analyser and vibrating sample magnetometer, and the corresponding attenuation mechanisms ofthe absorbents were discussed. The composite coatings with polyurethane as matrix were fabricated by employing carbon black, FSA and nmCIP as absorbents. Moreover, the microwave absorption properties of these composite coatings with different absorbents were measured by the arch method. Results showed that nmCIP was an efficient magnetic loss absorbent with lowdensity. The microwave absorption properties of the coatings were significantly enhanced: the peak value of reflection loss (RL) reached -25.8 dB, and bandwidth (RL<-10 dB) was expanded to 3.6 GHz. While it was composited with FSA, which had the same loss mechanism with nmCIP, the location of effective absorption band could be modified with reduced areal density. [ABSTRACT FROM AUTHOR]

Swift heavy ion (SHI) irradiation is a special technique for inducing physical and chemical modifications in bulk materials. In the present work, the SHI hs been used to prepare nanocomposites with homogeneously dispersed nanoparticles. The nanographite was synthesized from graphite using the intercalation–exfoliation method. PMMA Poly(methyl methacrylate)/graphite nanocomposites have been synthesized byin situpolymerization. The prepared PMMA/graphite nanocomposite films were irradiated with SHI irradiation (Ni ion beam, 80 MeV and C ion beam, 50 MeV) at a fluence of 1×1010to 3×1012 ions/cm2. The nanocomposite films were characterized by scanning electron microscope (SEM) and were evaluated for their electrical and sensor properties. After irradiation, significant changes in surface morphology of nanocomposites were observed as evident from the SEM images, which show the presence of well-distributed nanographite platelets. The irradiated nanocomposites exhibit better electrical and sensor properties for the detection of nitroaromatics with marked improvement in sensitivity as compared with unirradiated nanocomposites. [ABSTRACT FROM AUTHOR]

In this paper, we present the result of TiN nanocrystalline deposition on SS316L, using a 4 kJ plasma focus (PF) device for 10, 20, and 30 focus shots. The effect of different number of focus shots on micro-structural changes of thin film is characterized by field emission scanning electron microscope. Existence of grains in different size confirms the formation of TiN nanocrystals on the surface of SS316L substrate. X-ray diffraction (XRD) reveals the formation of a nanocrystalline titanium nitride coating on the surface of SS316L samples. The crystalline size of TiN obtained from XRD data is strongly dependent on the number of focus shots. Thickness of the elements found on the surface of the treated sample that obtain by Rutherford backscattering spectroscopy (RBS) analysis is in the range of 150×1015−200×1015 atoms/cm2. All the existence elements in the coated samples are identified by Particle Induced X-ray Emission (PIXE) spectra. Investigation on the corrosion resistance of TiN coatings was performed using an electrochemical potentiodynamic polarization. Our results suggest that TiN nanocrystalline implantation with proper ion fluences using PF can significantly improve the corrosion resistance of SS316L. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) nanoparticles formed by chemical in situ polymerization were deposited on the hydrophilic/hydrophobic surface of SiO2 substrates to give the diversely morphology, respectively. The morphologies of PPy nanoparticles deposit were investigated using optical microscope, scanning electron microscope (SEM), and atomic force microscope (AFM) imaging techniques. The morphology of Y- and T-shape wrinkles was observed on the hydrophilic surface of SiO2 substrate, while the morphology of polygon-shape wrinkles on the hydrophobic surface of SiO2 substrate, and this distinction is due to the difference of the surface energy between the hydrophilic and hydrophobic surface of SiO2 substrate and so-called “memory effect.” [ABSTRACT FROM AUTHOR]

Background: Micrometric and nanometric particles are increasingly used in different fields and may exhibit variable toxicity levels depending on their physicochemical characteristics. The aim of this study was to determine the impact of the size parameter on cellular uptake and biological activity, working with well-characterized fluorescent particles. We focused our attention on macrophages, the main target cells of the respiratory system responsible for the phagocytosis of the particles. Methods: FITC fluorescent silica particles of variable submicronic sizes (850, 500, 250 and 150 nm) but with similar surface coating (COOH) were tailored and physico-chemically characterized. These particles were then incubated with the RAW 264.7 macrophage cell line. After microscopic observations (SEM, TEM, confocal), a quantitative evaluation of the uptake was carried out. Fluorescence detected after a quenching with trypan blue allows us to distinguish and quantify entirely engulfed fluorescent particles from those just adhering to the cell membrane. Finally, these data were compared to the in vitro toxicity assessed in terms of cell damage, inflammation and oxidative stress (evaluated by LDH release, TNF-α and ROS production respectively). Results and conclusion: Particles were well characterized (fluorescence, size distribution, zeta potential, agglomeration and surface groups) and easily visualized after cellular uptake using confocal and electron microscopy. The number of internalized particles was precisely evaluated. Size was found to be an important parameter regarding particles uptake and in vitro toxicity but this latter strongly depends on the particles doses employed. [ABSTRACT FROM AUTHOR]

The present paper describes a method for producing graphitic carbon nanospheres (GCNSs) by chemical vapour deposition (CVD), which includes supplying carbon atoms to a catalyser for forming carbon nanoparticles in a controlled manner, in which the amount of carbon supply is controlled in relation to the time and temperature parameters. In this method short carbon fibres are used as supporting substrate for the mass formation of pure graphitic carbon nanoparticles in a fluidized bed reactor chemical vapour deposition (FBCVD). The synthesis of graphitic carbon nanoparticles (GCNPs) is carried out by the catalytic decomposition of a carbon source over a substrate deposited with catalyst in the fixed bed reactor. The chemical composition of nanoparticles was measured by energy dispersive X-ray spectrometry (EDX) in a scanning electron microscope (SEM). SEM, High Resolution Transmission Electron Microscope (HRTEM), thermal gravimetric analyser (TGA), and X-ray diffraction (XRD) were used for characterization of the catalyst and the products. This study indicates that GCNP is successfully grown at 600°C in ambient pressure for 1.8% Fe on carbon fiber, 8 minutes deposition time, and 15L/min acetylene flow rate. Graphitic carbon nanospheres have been produced in large amount of lattice images of various fullerenic carbons and aciniform of nanoparticles, which are seldom reported in the literature. [ABSTRACT FROM AUTHOR]

In this work, zinc nanoparticles were prepared by wet chemical method. The particles were examined by particle size analyzer, their morphology and micro structure were observed and elementally detected through scanning electron microphotography. Antimicrobial properties were evaluated using soil burial test. The effect of zinc nanoparticle treatment on physical properties and dyeing performance of cotton was evaluated. The work opened up a new avenue of manufacturing a new generation cotton nanocomposites with barrier properties against microbe with improved physical as well as dyeing performances. [ABSTRACT FROM AUTHOR]

Poly(trimethylene terephthalate) (PTT)/poly(ethylene-octene) POE-g-MA/organoclay ternary nanocomposites were prepared using melt blending in order to simultaneously improve the toughness and stiffness of PTT. The phase morphology and dispersion of organoclay were characterized by scanning electron microscope (SEM), X-ray diffractometer (XRD), and transmission electron microscopy (TEM). The melt rheological behavior of the ternary nanocomposites was determined by plate/plate rheological measurements. XRD and TEM analysis indicated that the ternary nanocomposites contained exfoliated nanoparticle when a small amount of organoclay (1 part per hundred) was added. The high aspect ratio of the organoclay platelets induced the average size of the dispersed domain to become smaller. Melt rheological studies revealed that the ternary nanocomposites exhibited strong shear thinning behavior and showed good processability. [ABSTRACT FROM AUTHOR]

Hybrid solar cells have attracted considerable attention in recent years due to their high thermal and chemical stability, light weight, high carrier mobility, and low cost. The active layer of cadmium selenide (CdSe) nanoparticles- poly(3-hexylthiophene) (P3HT) is optimized in terms of their mass ratio and microstructure by using absorption and scanning electron microscope (SEM). The active layer of hybrid solar cell formed with P3HT to CdSe mass ratio as 1:9 exhibits (i) maximum absorption of solar radiation in the wavelength range of 300-850 nm, (ii) provides fine dispersion of CdSe nanocrystals (average size ∼ 15 nm). Nanocrystal-polymer blend solar cell has been fabricated by the solution spin-casting process and characterized. The fabricated solar cell device shows short circuit current (Jsc) 0.51mA/cm2 and open circuit voltage (Voc) 0.44V. [ABSTRACT FROM AUTHOR]

The fabrication of nanopatterns with a focussed ion beam (FIB) has recently been expanded to more complex nanopatterns with large numbers of individual pattern elements and covering larger pattern areas. We present two examples of FIB-fabricated large and complex nanopatterns and describe the key aspects of the underlying process automation. The FIB-fabrication has been carried out on DualBeam™ instruments, which combine the FIB with a scanning electron microscope in one single instrument. We also present examples on how FIB-cross-sectioning and high-resolution electron microscopy can be applied to characterise the just fabricated nanopatterns in great detail. [ABSTRACT FROM AUTHOR]