Search

Wheat gliadin is thought to be the main cause of wheat allergy leading to celiac disease. In this study, we reported an electrochemical immunosensor based on AuNPs/Zn/Ni-ZIF-8-800@graphene for simple, efficient, and sensitive detection of gliadin. A monoclonal antibody against gliadin were prepared by hybridoma technique. Zn/Ni-ZIF-8-800 with high stability was prepared by using zinc–nickel bimetallic organic framework MOFs, and graphene and gold nanoparticles with large surface area and excellent conductivity were introduced. Chitosan was used as a binder to fixed the composite on the surface of glassy carbon electrode. The fabricated materials and the corresponding sensors were comprehensively characterized by X-ray diffractometer, scanning electron microscope, transmission electron microscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller, and cyclic voltammetry analyses. Under the optimal conditions, the linear range of the electrochemical immunosensor was 0.1–100 μg mL−1, and the detection limit was 0.950 μg mL−1. In addition, the fabricated sensor exhibited high selectivity and long-term stability. The recovery test showed that the prepared sensor was suitable for the detection of gliadin in real food and feed, exhibiting great promising of the developed sensor in practical application. [ABSTRACT FROM AUTHOR]

Thermoluminescence (TL) response of newly synthetic silicon-activated Ca9AlP7O28 nanophosphor doped with different concentrations (0.3–10 mol%) (abbreviated as CAP: Six) were prepared by the sol–gel method. The optimum concentration of Si ions for the best TL response was found to be 0.3 mol% (CAP: Si0.3), which was selected for subsequent dosimetric measurements. Phase purity and the crystal structure of the CAP: Si0.3 sample were identified and verified using X-ray diffraction (XRD) and transmission electron microscopy (TEM) analysis, where results obtained confirmed the successful synthetic method used in the preparation of the nanophosphor samples. Scanning electron microscope (SEM) and energy dispersive X-ray (EDX) mapping revealed the localization of constituent elements and indicated the homogeneous distribution of Si-ions as well as the feasibility of dopants in the herein sample. The dosimetric properties of the CAP: Si0.3 sample, including glow curve structure, reproducibility, repeatability, dose–response and fading effect, were extensively investigated. The gamma irradiated CAP: Si0.3 sample exhibited a simple glow curve of a single prominent peak centred at 222 ± 1.33°C with considerably high TL intensity (1.22 relative to MTS-700 TLD detector). The relative standard deviation (RSD) of peak areas of CAP: Si0.3 were 5.25 and 2.7% for reproducibility and repeatability studies, respectively. These values of RSD were <10%, so they were acceptable internationally. A good linear dose–response relationship was achieved over a dose range of up to 20 Gy with an excellent correlation coefficient of R2 = 0.9969 and a calibration factor of F = 51.75 × 107 a.u./Gy. Almost no fading was registered from the studied CAP: Si0.3 sample after irradiation. Zeff values were found to be in the range 11.62 to 11.61, which are closely related to that of natural bone (11.3 to 11.8). Minimum detectable dose of CAP: Si0.3 had a value of 11 μGy. The outstanding features of this herein-prepared sample make it a good TLD nanophosphor, very suitable for personnel and environmental dosimetry of γ-radiation within the studied dose range. [ABSTRACT FROM AUTHOR]

Cis-1,4-polyisoprene latex (IRL) is the best alternative to natural rubber latex (NRL) because it is free from proteins and can avoid allergic reactions in the human body. Poor mechanical properties of IRL film are a major obstacle to replacing NRL. To address this issue, a novel strategy was developed by a simple one-pot method to prepare a composite latex introducing hexadecyltrimethylammonium bromide (CTAB) modified sodium montmorillonite (org-Mnt) into the IRL preparation process. The microstructures and morphology of the resulting org-Mnt were characterized by Fourier Transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and Energy Dispersive Spectrometer (EDS). In addition, the dispersion state of the org-Mnt in the composite latex and the morphology of the composite films were determined by transmission electron microscopy (TEM) and SEM. The properties of the composite latex were investigated. Crosslink density, thermogravimetric analysis (TGA), mechanical properties, and thermal oxygen aging properties of the composite latex films were also studied. Finally, the mechanism of org-Mnt reinforcement of IRL was described comprehensively. The results showed that the org-Mnt/IRL (1phr and 2phr) composite latexes had a stable state, excellent film-formation performance, and excellent mechanical properties. Compared with pure IRL films, the tensile strength of org-Mnt/IRL (2phr) composite films increased by 74%, and after thermal oxygen aging, property change rates of the tensile strength and elongation at break increased by 37.2% and 32.1%, respectively, which exceeded those of NRL. The current research provides an effective method for preparing high-performance composite films suitable for high-end medical applications. [ABSTRACT FROM AUTHOR]

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

The TiB x /Ti x Ni y /TiC reinforced Ni60 composite coatings were successfully prepared on the surface of 35CrMoV substrate using the laser cladding technology by adding different content of LaB 6 (0, 0.5, 1.5, 2.5 wt%) powders into the mixture of TC4 (Ti6Al4V) and Ni60 (94 wt% Ni60, 6 wt% TC4). The phase composition, microstructure, element distribution and chemical composition of the cladding layer were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) with energy spectrum analysis (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), respectively. The reinforced phases in the cladding layer were mainly composed of TiB 2 , TiC, TiB, Ti 2 Ni, NiTi and Ni 3 Ti. The addition of LaB 6 did not affect the phase composition, but the grains are obviously refined and the distribution of Ni, Cr and Ti elements is uniform at the addition of 1.5 wt% LaB 6 addition. The cladding layer obtained excellent tribological and mechanical performance with the addition of 1.5 wt% LaB 6 , and the hardness, average friction coefficient and wear volume of the cladding layer reach 808 HV 1 , 0.183, and 8943 μm3, respectively. The reasonable addition of LaB 6 significantly improves the friction and mechanical properties of the cladding layer. [ABSTRACT FROM AUTHOR]

The direct impregnation approach is used to synthesize nickel dimethylglyoxime (NDG) on γ-alumina (γ-Al2O3) composites to be used as a catalyst. The structural, thermal, and magnetic characteristics of γ-Al2O3, NDG, and NDG/γ-Al2O3 composites are investigated and their photocatalytic performance towards methylene blue (MB) and methyl orange (MO) is examined. The finding supports the use of NDG over γ-Al2O3 as catalysts, besides their enhanced thermal stability. The scanning electron microscope (SEM) and transmission electron microscopy (TEM) demonstrate that the catalyst particles are dispersed uniformly, indicating that the Ni microcrystalline or Ni nanoparticles on γ-Al2O3 are most likely distributed in a single phase and/or in a homogenous route. X-ray diffraction (XRD) results together with the results of SEM and TEM indicated that NDG/γ-Al2O3 nanocomposite catalysts can be prepared effectively by impingement approach. The average crystallite size of γ-Al2O3 is 6 nm, whereas the average crystallite size of NDG/γ-Al2O3 composites is 10 nm. Both γ-Al2O3 and NDG/γ-Al2O3 composites have a weakly diamagnetic response, whereas NDG exhibits poor ferromagnetism response. The calculated values for the photodegradation efficiency, after UV–visible irradiation for 130 min, towards MO dye employing γ-Al2O3, NDG, and NDG/γ-Al2O3 composites as a catalyst are 74.2, 36.7, and 61.7%, respectively, whereas their values towards MB dye are 17.8, 5.3, and 19.1%, respectively. Furthermore, when NDG was combined with γ-Al2O3 to form NDG/γ-Al2O3 composites, the degradation performance was significantly improved and could be suitable for the degradation of other dyes. [ABSTRACT FROM AUTHOR]

A facile method was developed for preparing size-controlled silver nanoparticles supported by pyrolytic carbon from microcrystalline cellulose (MCC). The pyrolysis of cellulose-AgNO3 mixture caused the oxidation of cellulose, resulting in carboxyl groups to which silver ions can bind firmly and act as nuclei for the deposition of silver nanoparticles. The structure and properties of the obtained nanocomposite were characterized by using a scanning electron microscope (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) and X-ray diffraction (XRD). The results suggest that silver nanoparticles were integrated successfully and dispersed uniformly in the pyrolytic carbon matrix. The average particle size varied between 20 nm and 100 nm in correlation to the dose of silver nitrate and temperature of pyrolysis. The products showed high electric conductivity and strong antimicrobial activity against Escherichia coli (E. coli). [ABSTRACT FROM AUTHOR]

A facile, effective and green method using Ginkgo Biloba leaf extract was applied and optimized for the preparation of well dispersed silver nanoparticles. In the method, Ginkgo Biloba leaf extract was employed as both stabilizing and reducing agent without the addition of a toxic agent. 0.1 % silver nitrate solution (w/v) was used silver source. The synthesized silver nanoparticles were investigated and examined by UV-vis absorption spectroscopy (UV-vis), Scanning electron microscope (SEM), Transmission electron microscopy (TEM), powder X-ray diffraction (XRD) and Dynamic light scattering (DLS). The formation of silver nanoparticles was found by a change of color from light yellow to red, which was further proved by absorbance peak at 456 nm in UV-vis spectroscopy. The prepared nanoparticles are global in shape, highly crystalline in nature with a narrow distribution from 10 nm to 40 nm. The silver nanoparticles were capped with extracts, which prevented them from agglomeration and oxidation. Different parameters affecting the generation performance of silver nanoparticles, such as time, amount of silver nitrate and extract were investigated. The results demonstrate that these reaction parameters play important roles in the synthesis of silver nanoparticles. [ABSTRACT FROM AUTHOR]

Cu additions notably strengthen Al-Mg-Si and Al-Si-Mg alloys due to the dense precipitation of quaternary nano precipitates during ageing. However, the chemical evolution and mechanical behaviors of the quaternary micro-scale Q constituent phase occurring in cast and homogenized states have rarely been studied. Meanwhile, there exists a type of AlCuMgSi cluster in the cast state, which has been regarded as Q particles. The accurate identification of phase constituents is the basis for the future design of alloys with better performance. In our work, this type of cluster was revealed to consist of α-Al, θ-Al2Cu, Q, and Si phases through micro-to-atomic scale studies using scanning and transmission electron microscopes. The skeleton of the dendrite was θ phase. The second phases in the dendritic eutectic cluster dissolved quickly during a 4 h homogenization at 550 °C. The Q phase was found to effectively absorb the Fe impurities during casting and homogenization. As a result, the formation of other harmful Fe-rich intermetallics was suppressed. These Q constituent particles were observed to break into separate pieces in an intermediately brittle manner when compressed in situ in a scanning electron microscope. These findings provide insights into the thermodynamic modeling of the Al-Mg-Si-Cu system and alloy design. [ABSTRACT FROM AUTHOR]

This paper studies the chemical and mechanochemical preparation of glauconite with ammonium dihydrogen phosphate (ADP) nanocomposites with a ratio of 9:1 in the vol.% and wt.%, respectively. The methods include X-ray diffraction analysis, scanning electron microscope with energy-dispersive X-ray spectroscopy, transmission electron microscopy, infrared spectroscopy, and differential thermal analysis with a quadruple mass spectrometer. The manufactured nanocomposites keep the flaky glauconite structure. Some glauconite unit structures have been thickened due to minimal nitrogen (ammonium) intercalation into the interlayer space. The globular, granular, or pellet mineral particles of nanocomposites can be preserved via chemical techniques. Globular and micro-aggregate particles in nanocomposites comprise a thin film of adsorbed ADP. The two-step mechanochemical method makes it possible to slightly increase the proportion of adsorbed (up to 3.2%) and intercalated (up to 6.0%) nutrients versus chemical ways. Nanocomposites prepared via chemical methods consist of glauconite (90%), adsorbed (1.8–3.6%), and intercalated (3.0–3.7%) substances of ADP. Through the use of a potassium-containing clay mineral as an inhibitor, nitrogen, phosphorus, and potassium (NPK), nanocomposite fertilisers of controlled action were obtained. Targeted and controlled release of nutrients such as phosphate, ammonium, and potassium are expected due to various forms of nutrients on the surface, in the micropores, and in the interlayer space of glauconite. This is confirmed via the stepwise dynamics of the release of ammonium, nitrate, potassium, and phosphate from their created nanocomposites. These features of nanocomposites contribute to the stimulation of plant growth and development when fertilisers are applied to the soil. [ABSTRACT FROM AUTHOR]

Using the mixed solution of n -butanol and ethanol as solvent, the sodalite nanocrystal aggregate was prepared by the solvothermal method. The influences of crystallization temperature, molar ratio Na/Al, crystallization time and silane concentration on the morphology, crystallite size, degree of crystallization and pore structure of the as-prepared samples were investigated by X-ray diffraction (XRD), BET, FTIR, Transmission Electron Microscopy (TEM) and scanning electron microscope (SEM). The results reveal that the sodalite nanocrystals are aggregated by self-assembly into the micropore–mesopore–macropore structure. Higher crystallization temperature and longer crystallization time are conducive to the growth of sodalite nanocrystals. It is a necessary condition for the formation of sodalite nanocrystals to keep high molar ratio Na/Al. The higher the molar ratio Na/Al, the more favorable the crystallization of sodalite nanocrystals. The appropriate concentration of silane agent is conducive to the preparation of smaller crystal-sized sodalite nanocrystals. After removing the silane agent by pickling, the sodalite nanocrystal aggregate is a multistage porous structure with the pore volume of 1.0133 mL/g and the specific surface area of 449.73 m2/g. The preparation of nanocrystal sodalite by solvothermal method, the introduction of Hexadecyltrimethoxysilane as a surfactant, followed by acid pickling to remove the surfactant, produced multistage porous sodalite nanocrystal aggregate, greatly improving the mass transfer rate of sodalite, making it applicable to a wider range of fields. [ABSTRACT FROM AUTHOR]

Copper nanoparticles have been utilized in a variety of therapeutic applications because of their inexpensive manufacturing and unique characteristics. In the current study, novel nanocomposites are developed to carry bioactive agents in a controlled manner. Copper nanoparticles (Cu‐NPs) were synthesized from copper sulfate using a leaf extract of Phyllanthus virgatus as a reducing agent. The obtained Cu‐NPs are loaded into the polymeric matrix of sodium alginate and locust bean gum to generate microbeads. The developed microbeads were characterized by Fourier‐transform infrared (FTIR), X‐ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and scanning electron microscope (SEM). Swelling and in vitro release studies were performed at pH 2.0 and 7.4 at 37 °C. Metronidazole (MTD) was used as a model agent, and the antibacterial activity of microbeads was tested against Streptococcus mutans, Klebsiella pneumoniae, and Bacillus subtilis. The release kinetics and MTD release pattern were analyzed by employing the MTD release data into Korsmeyer‐Peppas equation and other kinetic models. [ABSTRACT FROM AUTHOR]

Oxidative desulfurization (ODS) is considered to be one of the most promising desulfurization processes as it is energy-efficient and requires mild operating conditions. In this study, a novel green synthesized Al- based metal–organic framework with high surface area has been synthesized hydrothermally using waste polyethylene terephthalate bottles (PET) as a source of terephthalic acid as an organic linker. The prepared Al based MOF have been characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM). The catalytic activity of the prepared Al-MOF was evaluated in the oxidative desulfurization (ODS) of both modeled and real crude oil samples. The different operating parameters (temperature, time, catalyst dose, oxidant loading and sonication) on the ODS performance have been optimized. The optimal conditions for maximum removal of thiophene from modeled oil samples were found to be 30 min, 0.5 g of catalyst and 1:3 oil to oxidant ratio. Under the optimized conditions, sulfur removal in real oil samples obtained from Alexandria petroleum company was 90%. The results revealed that, the presented approach is credited to cost-effectiveness, environmental benignity, and ease of preparation, predicting great prospects for desulfurization of fuel oils on a commercial level. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the effect of adding rhenium to Cu-Ni-Si alloys on the mechanical properties and electrical conductivity of these alloys. The scientific objective was to analyze the effect of Re addition on the microstructure of heat- and cold-treated CuNi2Si1 alloys. Transmission electron microscopy (TEM, STEM) and scanning electron microscopy (EDS, WDS) were used to examine the microstructure. Orientation mapping was also performed using a scanning electron microscope (SEM) equipped with a backscattered electron diffraction (EBSD) system. In addition, hardness at low load and conductivity were tested. The obtained results showed that modifying the chemical composition of Re (0.6 wt%) inhibits the recrystallization process in the CuNi2Si1 alloy, which was cold deformed and then subjected to recrystallization annealing. [ABSTRACT FROM AUTHOR]

To design more environmentally friendly, economical, and efficient demulsifiers for oily wastewater treatment, hydrophobic octadecylphosphonic acid (ODPA)-modified Fe3O4 nanoparticles (referred to as Fe3O4@ODPA) were prepared by condensation of hydroxyl groups between ODPA and Fe3O4 nanoparticles using the co-precipitation method. The prepared magnetite nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric/differential thermogravimetric (TG/DTG) analysis. The water contact angles (θW) of Fe3O4@ODPA nanoparticles were more than 120°, indicating hydrophobic nature, and the diameter of the obtained spherical-shaped magnetite nanoparticles was 12–15 nm. The ODPA coating amount (AO) (coating weight per gram Fe3O4) and specific surface area (SO) of Fe3O4@ODPA were 0.124–0.144 g·g−1 and 78.65–91.01 m2·g−1, respectively. To evaluate the demulsification ability, stability, and reusability, the magnetite nanoparticles were used to demulsify an n-hexane-in-water nanoemulsion. The effects of the magnetite nanoparticle dosage (CS), pH value of nanoemulsion, and NaCl or CaCl2 electrolytes on the demulsification efficiency (RO) were investigated. The RO of Fe3O4@ODPA samples was found to be higher than that of bare Fe3O4 samples (S0, ST, and SN) under all CS values. With the increase in CS, the RO of Fe3O4@ODPA samples initially increased and then approached equilibrium value at Cs = 80.0 g·L−1. A maximum RO of ~93% was achieved at CS = 100.0 g·L−1 for the Fe3O4@ODPA sample S2. The pH and two electrolytes had a minor effect on RO. The Fe3O4@ODPA nanoparticles maintained high RO even after being reused for demulsification 11 times. This indicates that the hydrophobic Fe3O4@ODPA samples can be used as an effective magnetite demulsifer for oil-in-water nanoemulsions. [ABSTRACT FROM AUTHOR]

Aiming at the disadvantage that nano ZnO is easy to agglutinate in the process of preparation and use, which will affect its antibacterial performance, experiments are designed to make nano ZnO compound with porous SiO2 in the sol-gel process. Through scanning electron microscope (SEM) and transmission electron microscopy (TEM), it can be found that ZnO is well combined on the porous SiO2 skeleton and dispersed evenly. The BET and PL tests show that the specific surface area of composites is improved and the optical properties are enhanced. The difference of antibacterial properties between composites and singlecomponent nano ZnO, and the change of antibacterial properties caused by the change of nano ZnO content in composites are investigated by the colony counting method. Conclusion is proved that the antibacterial properties of nano ZnO and porous SiO2 are greatly improved with the antibacterial rate of more than 99%. [ABSTRACT FROM AUTHOR]

The localised corrosion of aluminium alloy (AA) 5083-H111 in 3.5 wt-% NaCl solution was studied by combing scanning electron microscope (SEM), focused ion beam (FIB) and transmission electron microscopy (TEM) techniques. It was found that the Ti-rich intermetallic particles (IMPs) served as the cathodes and triggered the dissolution of its adjacent Al matrix; as a result, a trench was formed between the IMP and its surrounding Al matrix. Raised 'circles' were identified on the alloy surface at the periphery of the IMPs, which was considered to be the cathodic region on which corrosion products deposited. A sub-surface that consisted of fine Al grains and corroded Al–Mg phases were observed under the raised 'circle' region. [ABSTRACT FROM AUTHOR]

Nanodiamonds (NDs) are potential fillers that provide excellent mechanical and multifunctional capabilities. The growing interest in using NDs in a variety of fields has prompted researchers to use NDs to prepare various structural composites. In this work, ND surface modification was performed by a physical process as a systematic approach to remove the sp2 carbon content and noncarboneous particles from pristine NDs. The nanohardness and viscoelastic response of modified NDs incorporated with the epoxy matrix were further investigated. The surface morphology and crystalline nature of NDs/epoxy nanocomposites were investigated by scanning electron microscope, transmission electron microscopy, and x‐ray diffraction. Nanoindentation and nano‐dynamic mechanical analysis (DMA) tests were conducted on different composites with 0–0.5 wt% filler variations. The nanohardness and nano‐DMA of various composites were performed at two different loads (5 and 10 mN) in a frequency range of 10–250 Hz. The maximum improvement in the young's modulus was 79% and 52% with the 5 and 10 mN loads, respectively, corresponding to 0.3 wt% filler loading. The storage modulus and loss modulus values increased with the ND concentration in epoxy composites for 10 mN loads compared to 5 mN loads. From the nano‐DMA study, a higher phase lag of the tan δ curve was obtained for 5 and 10 mN loads, with larger tan δ values for NDs nanofiller‐loaded composites compared to neat epoxy. When compared to the 5 mN load, the tan δ value for the 10 mN load increased by 0.3 wt%. Thus, these composites can be used for automobiles and aerospace applications. [ABSTRACT FROM AUTHOR]

In this study, the ultralong SiC nanofibers (SiC NFs) were synthesized through the sol–gel method assisted the chemical vapor deposition technique. The scanning electron microscope, transmission electron microscopy, X‐ray diffraction, Raman, Fourier transform infrared, and X‐ray photoelectron spectroscopy techniques were systematically employed to investigate the microstructure, morphology, and phase composition of the as‐prepared products. The results demonstrated that the as‐obtained products were β‐SiC nanofibers with face‐centered cubic crystal structure. Meanwhile, the ultralong SiC NFs present an average diameter of about 18 nm and a length up to several hundreds of micrometers and grew along the [1 1 1] direction with a planar stacking faults. In addition, we also investigated the formation mechanism and growth process of the ultralong SiC NFs. The successful preparation of such ultralong SiC NFs provides new idea for fabricating of other silicon‐based ultralong nanofibers. [ABSTRACT FROM AUTHOR]

Flexible electrodes using nanowires (NWs) suffer from challenges of long-term stability and high junction resistance which limit their fields of applications. Welding via thermal annealing is a common strategy to enhance the conductivity of percolated NW networks, however, it affects the structural and mechanical integrity of the NWs. In this study we show that the decoration of NWs with an ultrathin metal oxide is a potential alternative procedure which not only enhances the thermal and chemical stability but, moreover, provides a totally different mechanism to reduce the junction resistance upon heat treatment. Here, we analyze the effect of SnO x decoration on the conductance of silver NWs and NW junctions by using a four-probe measurement setup inside a scanning electron microscope. Dedicated transmission electron microscopy analysis in plan-view and cross-section geometry are carried out to characterize the nanowires and the microstructure of the junctions. Upon heat treatment the junction resistance of both plain silver NWs and SnO x -decorated NWs is reduced by around 80%. While plain silver NWs show characteristic junction welding during annealing, the SnO x -decoration reduces junction resistance by a solder-like process which does not affect the mechanical integrity of the NW junction and is therefore expected to be superior for applications. [ABSTRACT FROM AUTHOR]

Functional cotton fabrics using silver-based nanoparticles (AgNPs) have attracted a lot of attention as a new generation of healthcare wearable textile. In this study, cotton fabrics were coated via impregnation with silver nanoparticles using chitosan (Cs) and (or) chitosan–organosilica (Cs-OSH) solutions as adhesives matrices. The physicochemical properties were studied using UV–VIS spectroscopy, and transmission electron microscopy (TEM) and scanning electron microscope coupled with energy-dispersive X-ray spectroscopy methods (SEM–EDX). The antibacterial activity of the silver-treated fabrics was determined using agar diffusion method. However, nanosize spherical AgNPs were observed in Cs and Cs-OSH solution. The average particle diameter was around 10 nm for Cs/AgNPs sample and close 21 nm for Cs-OSH/AgNPs. Microscopy images showed the deposition of Ag NPs on the surface of cotton fibers. The results indicated that the cotton fibers treated with Cs-OSH/AgNPs solution showed good stability against washing and maintained higher antimicrobial activity even after being exposed to 10 consecutive home laundering conditions. Thus, this work suggests the use of chitosan–organosilicon matrix to improve the bonding between AgNPs and cotton fibers for better and long-term antimicrobial activity. [ABSTRACT FROM AUTHOR]

The paper aims to investigate the influence of silver addition on the microstructure of CuNi2Si1 alloys. The investigated copper alloy was cast and then supersaturated, plastically deformed on the Gleeble 3800 simulator and finally aged. Structural changes were examined using optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Orientation mapping was completed with FEI Quanta 3D field emission gun scanning electron microscope (SEM) equipped with TSL electron backscattered diffraction (EBSD) system. The effect of structural and microstructural changes on hardness and conductivity was also investigated. Based on the mechanical tests it was found that the mechanical properties and conductivity are improved due to heat and plastic treatment. It was also found that the precipitation hardening raises the hardness to the level of 40% whilst an increase in conductivity by 20% is observed. [ABSTRACT FROM AUTHOR]

A new electrochemical impedimetric sensor for direct detection of urea was designed and fabricated using nanostructured screen-printed electrodes (SPEs) modified with CuO/Co3O4 @MWCNTs. A facile and simple hydrothermal method was achieved for the chemical synthesis of the CuO/Co3O4 nanocomposite followed by the integration of MWCNTs to be the final platform of the urea sensor. A full physical and chemical characterization for the prepared nanomaterials were performed including Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), contact angle, scanning electron microscope (SEM) and transmission electron microscopy (TEM). Additionally, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties the modified electrodes with the nanomaterials at different composition ratios of the CuO/Co3O4 or MWCNTs. The impedimetric measurements were optimized to reach a picomolar sensitivity and high selectivity for urea detection. From the calibration curve, the linear concentration range of 10−12–10−2 M was obtained with the regression coefficient (R2) of 0.9961 and lower detection limit of 0.223 pM (S/N = 5). The proposed sensor has been used for urea analysis in real samples. Thus, the newly developed non-enzymatic sensor represents a considerable advancement in the field for urea detection, owing to the simplicity, portability, and low cost-sensor fabrication. [ABSTRACT FROM AUTHOR]

Here, the magnetic Fe3O4@SiO2/PAEDTC@MIL-101 (Fe) with a new core-shell structure was synthesized, and its sonophotocatalytic properties were evaluated for acid red 14 (AR14) degradation. Particle characterizations were determined by scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and vibrating-sample magnetometer (VSM), and the analysis results offered an excellent synthesis of mesoporous particles. Fe3O4@SiO2/PAEDTC@MIL-101 (Fe)/UV/US showed high degradation kinetics rate (0.0327 min−1) compared to sonocatalytic processes (0.0181 min−1), photocatalytic (0218 min−1), sonolysis (0.008 min−1), and photolysis (0.005 min−1). Maximum removal efficiencies of AR14 (100%) and total organic carbon (69.96%) were obtained at pH of 5, catalyst mass of 0.5 g/L, initial AR14 concentration of 50 mg/L, and ultrasound power of 36 W. Evaluation of BOD5/COD ratio during dye treatment confirmed that the sonophotocatalysis process can be useful for converting major contaminant molecules into biodegradable compounds. After recycling eight times, the prepared composite still has sonophotocatalytic degradation stability above 90% for AR14. Scavenging tests confirmed that holes (h+) and hydroxyl (•OH) were the pivotal agents in the decomposition system. Based on the results, the synthesized sample can be suggested as an excellent and promising sonophotocatalyst for the degradation of AR14 dye and its conversion into biodegradable compounds. [ABSTRACT FROM AUTHOR]

In this study, the removal of bisphenol A (BPA), 2,4-dinitrophenol (2,4-DNP), and 2,4-dichlorophenol (2,4-DCP) using a new magnetic adsorbent methacrylic acid-functionalized β-cyclodextrin (Fe3O4@MAA-βCD) was evaluated. The materials were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, transmission electron microscopy, and X-ray diffraction. The batch adsorption experiments optimized and evaluated various operational parameters such as pH, contact time, sorbent dosage, initial concentration, and temperature. The result shows that DNP possessed the most excellent affinity toward Fe3O4@MAA-βCD adsorbents compared to BPA and DCP. Also, BPA showed the lowest removal and was used as a model analyte for further study. The adsorption kinetic data revealed that the uptake of these compounds follows the pseudo-second order. Freundlich and Halsey isotherms best-fitted the adsorption equilibrium data. The desorption process was exothermic and spontaneous, and a lower temperature favored the adsorption. Furthermore, hydrogen bonding, inclusion complexion, and π–π interactions contributed to the selected phenolic compound's adsorption. [ABSTRACT FROM AUTHOR]

In this work, the packed thickness of pyrite's effect on its conversion behavior and kinetics was investigated under air in high temperatures. The results showed that pyrite was oxidized to hematite directly with no more than 2 mm packed thickness, or indirect oxidation occurred (pyrite → pyrrhotite → hematite) when greater than 2 mm. Subsequently, the evolutions of pyrite were studied comprehensively by X-ray diffraction (XRD), Raman, Scanning electron microscope (SEM), and Transmission electron microscopy (TEM). The kinetics by the Avrami – Erofeev method displayed that the activation energy of the process of pyrite → hematite (27 KJ·mol−1) < pyrite → pyrrhotite (34 KJ·mol−1) < pyrrhotite → hematite (42 KJ·mol−1). The thinner-packed pyrite requires less energy to oxidize and more readily undergoes direct oxidation. The thermodynamics theoretically explained the reasons for indirect/direct oxidation of thicker-packed/thinner-packed pyrite that ΔGpyrrhotite < ΔGhematite in the thicker packed, or ΔGpyrrhotite > ΔGhematite in the thinner packed. This paper provided some fundamental and significant knowledge of pyrite oxidation to reduce SO2 emissions and industrial production safety. [ABSTRACT FROM AUTHOR]

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

This research focuses on a novel visible light-responsive photocatalysis system employing MoS2 and magnetically responsive BiFeO3 for removing dye. Novel BiFeO3/MoS2 magnetic nanocomposite was successfully synthesised by a simple method and characterised by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), Uv–Vis diffuse reflection spectra (DRS) and vibrating sample magnetometry (VSM). Comparing with pure BiFeO3 and MoS2, the prepared nanocomposite illustrated notably better photocatalytic activity. The outcome of the photocatalytic experiments depicted that nanocomposite reaches to about 89% removal of Rhodamine B in 200 min under visible light irradiation. The superior photocatalytic activity could be attributed to the high separation efficacy of the photogenerated electron-hole pairs. Moreover, the BiFeO3/MoS2 nanocomposite can be separated and collected easily by an external magnetic field and maintain high activity after three times photoreaction cycles. Trapping experiments have contributed to propose the possible mechanism for the improved photocatalytic activity of the nanocomposite. [ABSTRACT FROM AUTHOR]

The dispersion of carbon nanotubes (CNTs) is the bottleneck in CNT-reinforced metal matrix composites. In this work, CNT/Mg composites were prepared by grinding Mg powder and then dispersing CNTs via ball milling and hot pressing. The uniform distribution of Ni-coated CNTs in the matrix was achieved by optimizing the content of CNTs. Scanning electron microscope, high-resolution transmission electron microscopy and X-ray diffraction, optical microscopy, and compression tests were employed. With the CNT content being less than 1%, the CNTs can be evenly distributed in CNT/Mg composites, resulting in a sharp increase in strength. However, with the higher CNT content, the CNTs gradually cluster, leading decreased fracture strain and strength. Furthermore, the coated Ni in the CNTs reacts with the magnesium matrix and completely transforms into Mg2Ni, significantly enhancing the interface bonding. This strong interface bonding and the diffusely distributed Mg2Ni in the matrix significantly strengthen the CNT/Mg composite. [ABSTRACT FROM AUTHOR]

The mechanical properties of (Ti, Nb)B/Ti2AlNb composites were expected to improve further by utilizing spark plasma sintering (SPS) and inducing the novel three-dimensional network architecture. In this study, (Ti, Nb)B/Ti2AlNb composites with the novel architecture were successfully fabricated by ball milling the LaB6 and Ti2AlNb mixed powders and subsequent SPS consolidation. The influence of the (Ti, Nb)B content on the microstructure and mechanical properties of the composites was revealed by using the scanning electron microscope (SEM), transmission electron microscopy (TEM) and electronic universal testing machine. The microstructural characterization demonstrated that the boride crystallized into a B27 structure and the α2-precipitated amount increased with the (Ti, Nb)B increasing. When the (Ti, Nb)B content reached 4.9 vol%, both the α2 and reinforcement exhibited a continuous distribution along the prior particle boundaries (PPBs). The tensile test displayed that the tensile strength of the composites presented an increasing trend with the increasing (Ti, Nb)B content followed by a decreasing trend. The composite with a 3.2 vol% reinforcement had the optimal mechanical properties; the yield strengths of the composite at 25 and 650 °C were 998.3 and 774.9 MPa, showing an 11.8% and 9.2% improvement when compared with the Ti2AlNb-based alloy. Overall, (Ti, Nb)B possessed an excellent strengthening effect and inhibited the strength weakening of the PPBs area at high temperatures; the reinforcement content mainly affected the mechanical properties of the (Ti, Nb)B/Ti2AlNb composites by altering the α2-precipitated amount and the morphology of (Ti, Nb)B in the PPBs area. Both the continuous precipitation of the brittle α2 phase and the agglomeration of the (Ti, Nb)B reinforcement dramatically deteriorated the mechanical properties. [ABSTRACT FROM AUTHOR]

In the present work, the facile eco-friendly synthesis and evaluation of the anti-tumor activity of Ni(OH)2@Mn3O4 nanocomposite were carried out. The synthesis of Ni(OH)2@Mn3O4 nanocomposite from chia-seed extract was mediated by sonication. The obtained materials were characterized by different spectroscopic techniques such as transmission electron microscopy (TEM), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-Vis), and Fourier transform infrared (FT-IR) spectroscopies. The results of XRD, SEM, EDS, TEM, FT-IR, and UV-Vis analysis indicate the successful manufacturing of a crystalline, cactus-type Ni(OH)2@Mn3O4 nanocomposite of 10.10 nm average particle size. XPS analysis confirms that the synthesized materials consist mainly of Ni2+, Mn2+, and Mn3+. The antitumor activity of the nanocomposite was tested against a breast cancer (MCF-7) cell line. The results showed Ni(OH)2@Mn3O4 nanocomposite possesses insignificant cytotoxicity. The cell-death percentage was 34% at a 100 ppm concentration of Ni(OH)2@Mn3O4 nanocomposite. The obtained results imply that the synthesized nanocomposite could be suitable and safe for drug delivery and water treatment. [ABSTRACT FROM AUTHOR]

In order to control diesel exhaust emission, CeO2-SnO2/Al2O3 (CTA) mixed oxides were prepared and coated on perforated stainless steel (SS) filter plates, and the catalytic activities were analyzed in this work. The CeO2-SnO2 (different compositions of Ce/Sn—2:8; 1:1; 8:2) composites and Al2O3 were prepared separately via a co-precipitation approach, and CeO2-SnO2/Al2O3 (CTA) mixed oxides were attained by mechanical mixing of 75 wt% CeO2-SnO2 composites with 25 wt% Al2O3. X-ray diffraction (XRD) and Raman spectroscopy were performed for all three CeO2-SnO2/Al2O3 (CTA) mixed oxides; the CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample confirmed the presence of cubic and tetragonal mixed faces, which enhances the redox nature (catalytic activities). Various characterizations such as high-resolution transmission electron microscopy (HRTEM), Brunauer–Emmett–Teller (BET) analysis, X-ray photoelectron spectroscopy (XPS), and a scanning electron microscope (SEM) were employed on CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample to investigate the structural, textural, compositional, and morphological properties. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample was coated on a perforated stainless steel (SS) filter plate via a simple, cost-effective, and novel method, and an exhaust emission test for various compression ratios (CR), injection pressure (IP), and load (L) was completed using an AVL Digas analyzer. The CeO2-SnO2/Al2O3 (Ce/Sn-1:1) sample, with a size of 10.22 nm and a high surface area of about 73 m2 g−1, exhibit appreciable catalytic properties. [ABSTRACT FROM AUTHOR]

Layered Ni(II) complex on magnetic nanoparticle as heterogeneous, efficient, novel, green, and reusable catalyst was used to cross‐coupling reaction, including carbon–carbon, carbon–nitrogen, and carbon–oxygen formations. The covalent functionalization of organic ligand, thiocarbohydrazide (TCH), on the surface of magnetic nanoparticle (Fe3O4) was determined that leading to an exceptional adsorptive ability for supporting Ni(II). The magnetic nano‐composite was characterized and investigated by using Fourier‐transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), energy dispersive X‐ray (EDX), X‐ray diffraction (XRD), scanning electron microscope (SEM), inductively coupled plasma–optical emission spectrometry (ICP‐OES), transmission electron microscopy (TEM), and Brunauer–Emmett–Teller (BET). Also, three cross‐coupling reactions in the presence of Fe3O4@TCH@Ni(II) were optimized in terms of temperature, amount of catalyst, solvent, and time. [ABSTRACT FROM AUTHOR]

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

Nanostructure-based resistive switching memory devices are being developed for low power, multilevel storage capability, extended retention capacity, and scalable devices. The zinc tungstate (ZnWO 4) nanoparticle was prepared via the facile hydrothermal method. The X-ray diffraction technique confirmed ZnWO4 monoclinic phase and crystallite nature. The scanning electron microscope was used to identify the rod-like ZnWO4 nanostructure, and further, the lattice orientation was investigated by high-resolution transmission electron microscopy. X-ray photoelectron spectroscopy confirmed the binding states with composition of ZnWO4. Resistive switching memory based on ZnWO4 was produced and resulted in low-operating voltage. Finding new candidates for the emerging resistive memory technology is vital for the development of next-gen non-volatile memory devices and this study explored the feasibility of one of the multi-functional metal tungstate materials, ZnWO4 in the ReRAM memory application. The synthesized nanostructures are characterized to acquire the composition and bonding features which are crucial for the device performance. A non-volatile memory device based on ZnWO4 nanostructures synthesized through hydrothermal method is fabricated and the device performance is studied deliberately. [ABSTRACT FROM AUTHOR]

Titanium‐based metal‐organic framework MIL‐125(Ti) was synthesized by the hydrothermal method of terephthalic acid and tetra butyl titanate in N‐N,dimethylformamide, and methanol. MIL‐125(Ti) was characterized by Fourier‐transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, nitrogen adsorption‐desorption, energy‐dispersive X‐ray spectroscopy, zeta potential, scanning electron microscope, and transmission electron microscopy. The results showed MIL‐125(Ti) could be used as a potential adsorbent for protein separation and purification due to the high specific surface area, high stability, and strong hydrophobicity. As a result, MIL‐125(Ti) had adsorption selectivity for immunoglobulin G, which was due to the hydrogen bond between MIL‐125(Ti) and protein. At pH 8.0, the maximum adsorption efficiency of 0.25 mg MIL‐125(Ti) for 300 μL 100 μg/mL immunoglobulin G was 98.3%, and its maximum adsorption capacity was 232.56 mg/g. The elution efficiency of immunoglobulin G was 92.4% by 0.1% sodium dodecyl sulfate. sodium dodecyl sulfate‐polyacrylamide gel electrophoresis result demonstrated the successful isolation of highly purified immunoglobulin G from the human serum. Therefore, a new method of separation and purification of immunoglobulin G in human serum using titanium‐based metal‐organic framework MIL‐125(Ti) as a solid‐phase adsorbent was established, which broadened the application scope of metal‐organic frameworks. [ABSTRACT FROM AUTHOR]

Ikaite is a calcium carbonate hexahydrate that forms at temperatures close to the freezing point of water; thus, its occurrence is associated with cryogenic conditions. This mineral is metastable and quickly transforms to calcite at temperatures above 5 °C. Pseudomorphs of calcite after ikaite are known as glendonite. The nanostructure of 25 000–43 000 year old glendonite from Victoria cave (Southern Ural, Russia) was investigated in search of structural features indicative of the ikaite-to-calcite transformation. Scanning electron microscope images display several micrometer- to submicrometer-size pores and indicate high intergranular porosity among the loosely aggregated grains. Transmission electron microscopy (TEM) data show evidence of 10–20 nm nanotwins [twin law (101̅4)] and 10–40 nm overlapping nanograins. Scanning TEM images reveal that the individual grains contain 5–10 nm long and 2–4 nm wide mesopores (sizes between 2 and 50 nm), which are aligned parallel to [1010] of calcite and might be associated with a crystallographically oriented dehydration of the precursor ikaite. Fourier transform infrared spectroscopy reveals no evidence of structural water but absorption bands related to molecular water trapped in fluid inclusions are present. Nitrogen absorption/desorption measurements show that the specific surface area of 5.78 m2/g and the pore volume of ~0.07 cm3/g for calcite, the constituent of glendonite, are comparable to those of a common natural calcite. We suggest that the aligned mesopores, frequently occurring twins, small grain size, presence of aqueous inclusions and the high micrometer- to submicrometer-size intergranular porosity arise from the ikaite-to-calcite transformation and thus may be used as criteria for the former presence of ikaite and hence for cold paleotemperatures. However, since similar features might also be common in biogenic carbonates, the diagnostic macroscopic pseudomorphs after ikaite are equally important for identifying glendonites and inferring cryogenic conditions. [ABSTRACT FROM AUTHOR]

Taking advantage of electron diffraction based measurements, in a scanning electron microscope, can deliver non-destructive and quantitative information on extended defects in semiconductor thin films. In this work, we have studied a (11-22) semi-polar GaN thin film overgrown on regularly arrayed GaN micro-rod array templates grown by metal organic vapour phase epitaxy. We were able to optimise the diffraction conditions to image and quantify basal plane stacking faults (BSFs) and threading dislocations (TDs) using electron channelling contrast imaging (ECCI). Clusters of BSFs and TDs were observed with the same periodicity as the underlying micro-rod array template. The average BSF and TD densities were estimated to be ≈4 × 104 cm−1 and ≈5 × 108 cm−2, respectively. The contrast seen for BSFs in ECCI is similar to that observed for plan-view transmission electron microscopy images, with the only difference being the former acquiring the backscattered electrons and the latter collecting the transmitted electrons. Our present work shows the capability of ECCI for quantifying extended defects in semi-polar nitrides and represents a real step forward for optimising the growth conditions in these materials. [ABSTRACT FROM AUTHOR]

Twin-roll casting (TRC), as a near-net-shape technology, is employed to fabricate age-hardened Al-Mg-Si alloy. Compared with conventional direct chill (DC) casting, the TRC method is much more economical and efficient. In this work, the microstructure, precipitates behavior, and mechanical properties of age-hardened Al-Mg-Si alloy sheet fabricated by TRC were investigated by hardness measurements and tensile tests, metallographic microscopy, field emission gun scanning electron microscope, electron backscatter diffraction, transmission electron microscopy, and differential scanning calorimetry analyses. It was found that the size of recrystallized grains for DC casting alloy with finely dispersed particles was larger than that of TRC alloy with coarse particles. Typical CubeND texture accompanied by P texture formed after solution treatment made the value of r reach ~0.7 in the TRC alloy due to the PSN effect caused by the segregation of particles. More GP zones resulted in the strength of TRC alloy being higher than that of DC casting alloy after T8X treatment. With the time of paint-bake hardening extended to 8 h, few segregation particles remained in the TRC alloy. This decreased the concentration of supersaturated atoms. The hardness of the TRC alloy with the lower density of the β″ strengthening phase was lower compared to the DC casting alloy. [ABSTRACT FROM AUTHOR]

The synthesis of carbon nanowalls (CNWs) necessitated a substrate heating temperature above 600 °C. This study describes a low-temperature growth at 225 °C and characterization of CNWs synthesized by the radical injection plasma-enhanced chemical vapor deposition. To investigate the effect of temperature on the growth process, CNWs were synthesized at various temperatures ranging from 200 °C to 700 °C. The morphology of the CNWs observed with a scanning electron microscope shows that wall density increases as substrate temperature decreases. The Raman spectroscopy analysis indicates that CNWs grown at 225 °C have higher defect levels than those grown at higher temperatures, such as 700 °C. Transmission electron microscopy confirmed the presence of multiple graphene layers in the CNWs grown at 225 °C. The water contact angle results revealed that CNWs grown at 225 °C had higher hydrophobicity than those grown at higher temperatures, opening up the potential for CNW applications. [Display omitted] • Carbon nanowalls (CNWs) are grown at a low temperature of 225 °C. • A possible growth mechanism of the CNWs at 225 °C including 4 stages is proposed. • CNWs grown at 225 °C show a better hydrophobicity than typical CNWs grown at 700 °C. • Effect of substrate temperature on the growth process of CNWs is revealed. [ABSTRACT FROM AUTHOR]

Trichomonas vaginalis is an extracellular flagellate protozoan and the etiological agent of human trichomoniasis, a sexually transmitted infection (STI) with a high incidence. Several reports have shown that this protozoan releases microvesicles into the culture medium, which show high potential in modulating cell-to-cell communication and the host response to infections. However, the biogenesis of these vesicles has not been analyzed in detail. In the present study, high-resolution ion scanning microscopy (SEM) and transmission electron microscopy (TEM) were used to analyze the surface of control cells and cells incubated in the presence of Ca2+ alone or with A 23187 calcium ionophore. Two different strains of T. vaginalis were analyzed. Most control cells displayed relatively smooth surfaces, whereas cells incubated with Ca2+ had many surface projections of variable shape and size (from 40 nm to around 1 μm). Quantitative analyses were performed directly in the scanning electron microscope and showed a significant increase in the number of cells with surface projections after incubation in the presence of calcium. TEM showed that treated cells presented several cytoplasmic multivesicular structures, suggesting membrane fusion and exosomes in the extracellular medium. The amount and size of the released vesicles were quantitatively analyzed using light scattering and TEM on negatively stained samples. The observations show that incubation of both parasite strains in the presence of Ca2+ significantly increased the release of microvesicles into the extracellular medium in a time-dependent process. Sequential incubation in the presence of Ca2+ and the calcium ionophore A23187 increases the presence of vesicles on the parasite surface only at a short incubation time (5 min). Transmission electron microscopy showed that at least part of the vesicles are originated from cytoplasmic multivesicular structures. This information contributes to a better understanding of the biogenesis of extracellular vesicles secreted by T. vaginalis. [Display omitted] • Two strains of T. vaginalis presenting diferente virulence grades were tested concerning microvesicles liberation. • Stimulation for microvesicles liberation was done using calcium and calcium ionophore. • A scanning high-resolution ion microscopy was used to better visualize the cell surface with protruding microvesicles. • No diferences were observed between two T. vaginalis strains one with low virulence and another with high virulence concerning number of microvesicles. • Microvesicles images with ion SEM high resolution are shown. [ABSTRACT FROM AUTHOR]

Developing targeted and slow-release antibiotic delivery systems can effectively reduce drug overdose and side effects. This study aimed to investigate the antimicrobial activity of vancomycin-loaded soy protein nanoparticles (vancomycin-SPNs). For the preparation of SPNs, the desolvation method was applied in different concentrations of vancomycin and soy protein (15:5, 10:15, 6:20, 8:25, and 10:30 of vancomycin:soy protein). Scanning electron microscope (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and FTIR were used for nanoparticle characterization. Antibacterial activity was evaluated by the radial diffusion assay (RDA) and absorbance methods. Proper synthesis was demonstrated by characterization. The best drug loading (% entrapment efficiency = 90.2%), the fastest release rate (% release = 88.2%), and the best antibacterial activity were observed in ratio 10:30 of vancomycin:SPNs. Results showed that SPNs are a potent delivery system for antibiotic loading and slow release to control antibiotic use. [ABSTRACT FROM AUTHOR]

Metal ferrites have outstanding electrochemical characteristics owing to the numerous oxidation states of the metal ions, making them promising materials for addressing both sustainable energy conversion and storage and growing environmental issues. Therefore, three nanocrystallites transition metal ferrites, CoFe2O4, CuFe2O4 and Co/CuFe2O4, were synthesized using citrate precursors and used as electrode materials for supercapacitor applications. Mixed transition metal ferrite nanoparticles were characterized by Fourier transform infrared (FT-IR), scanning electron microscope (SEM) complemented with energy-dispersive spectroscopy (EDX), transmission electron microscopy (TEM), Raman spectroscopy and thermal analysis (TGA). The findings illustrated the formation of a single-phase spinel ferrite as proved from XRD data. In addition, the particle shape and particle size obtained from TEM analysis revealed that the as-synthesised nanomaterial exhibited spherical shape with a size ranging from 30 to 50 nm. The result demonstrated that while using a three-electrode configuration, the electrochemical performance of the ferrite nanoparticles achieved a remarkable maximum specific capacitance of 893 Fg−1 at a scan rate of 5 mV s−1. At a current density of 1 Ag−1, Co–Cu ferrite exhibited outstanding cycling stability for 3000 cycles with 90% capacity retention. Based on the aforementioned data, it can be considered that the remarkable electrochemical performance of the Co–Cu ferrite nanocomposites can be considered as promising materials to be used for supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

Summary: This study aims to fabricate mineral‐loading nanocarriers using natural materials. The interaction patterns between ovalbumin (OVA) and four water‐soluble polyphenols, namely ferulic acid (FA), (‐)‐Epigallo‐catechin 3‐gallate (EGCG), gallic acid (GA) and epicatechin (EC), were investigated. Results showed that the optimised conditions for preparing stable OVA–polyphenol complexes are at the OVA–polyphenol ratio of 4:1 at pH 6, under which OVA–FA and OVA–EGCG showed the highest stability and mineral‐loading capacity among four OVA–polyphenol complexes. The fluorescence results indicated that the addition of EGCG and FA induced a significant fluorescence quenching to OVA. The interaction between OVA and polyphenols involved hydrogen bonding, hydrophobic interaction and electrostatic interaction. Fourier transform infrared spectroscopy (FTIR) analysis suggested that both FA and EGCG enhanced the stability and orderliness of the structure of OVA. The transmission electron microscopy images also exhibited the spherical structure of OVA after the addition of FA and EGCG. Furthermore, scanning electron microscope–energy dispersive X‐ray spectrum results suggested that OVA–FA and OVA–EGCG complexes were better mineral carriers than OVA–GA and OVA–EC. This study may serve as the theoretical support for the promising application of OVA in the fabrication of mineral‐loading nanocarriers in functional food and pharmaceutic. [ABSTRACT FROM AUTHOR]

The present investigation was carried out to investigate the antibacterial efficiency of silver nanoparticles (AgNPs) in vitro against Aeromonas hydrophila using disc diffusion assay and minimum inhibitory concentration. The pathogenic A. hydrophila was isolated from infected common carp, usually diagnosed by chemical methods, and Avitek 2 compact device were used to confirm the diagnosis. The effectiveness of the prepared AgNPs was tested by chemical and biological (green synthesis using lemon extract) methods and were diagnosed by Fourier-transform infrared spectroscopy (FTIR), UV-Visible spectroscopy, Transmission electron microscopy (TEM), scanning electron microscope (SEM), which was spherical shape of the nanosilver and the size ranged between 30-50 nm. Results of disc diffusion assay showed that the chemical synthesized of AgNPs in 18hr recorded the highest inhibition zone followed by the bio-synthesized AgNPs and Oxytetracycline respectively. After 24 hr the highest inhibition zone was registered in Oxytetracycline, however after 5 days bio-synthesized AgNPs showed the higher inhibition zone which was significantly different(P≤0.05) in comparison to other products. Based on these results, both bio and chemical synthesized of AgNPs were effectively act as antibacterial against A.hydrophila. However, green synthesis using lemon extract is considered better antibacterial with low MIC than chemical AgNPs because lemon extract is regarded eco-friendly and also the low cost product compared to chemical AgNPs synthesis. [ABSTRACT FROM AUTHOR]

Compositional analysis of boron carbide on nanometer length scales to examine or interpret atomic mechanisms, for example, solid‐state amorphization or grain‐boundary segregation, is challenging. This work reviews advancements in high‐resolution microanalysis to characterize multiple generations of boron carbide. First, ζ‐factor microanalysis will be introduced as a powerful (scanning) transmission electron microscopy ((S)TEM) analytical framework to accurately characterize boron carbide. Three case studies involving the application of ζ‐factor microanalysis will then be presented: (1) accurate stoichiometry determination of B‐doped boron carbide using ζ‐factor microanalysis and electron energy loss spectroscopy, (2) normalized quantification of silicon grain‐boundary segregation in Si‐doped boron carbide, and (3) calibration of a scanning electron microscope X‐ray energy‐dispersive spectroscopy (XEDS) system to measure compositional homogeneity differences of B/Si‐doped arc‐melted boron carbides in the as‐melted and annealed conditions. Overall, the improvement and application of advanced analytical tools have helped better understand processing–microstructure–property relationships and successfully manufacture high‐performance ceramics. [ABSTRACT FROM AUTHOR]

In the present research, a new method for the aerobic oxidation of aromatic and cyclic aliphatic alcohols to the corresponding aldehydes or ketone was developed in the presence of two supported metalloporphyrins. The prepared heterogenized catalysts were fully characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM), thermogravimetric analysis (TGA), atomic absorption spectroscopy (AAS), Fourier Transform Infrared (FT‐IR) and Ultra Violet‐Visible (UV‐Vis) spectroscopy. The role of structural and textural properties of carbon‐based materials as solid support on the catalytic efficiency of the supported catalysts was compared with each other and the results shows higher efficiency of the supported Fe‐porphyrin on multi‐walled carbon nanotube [Fe(THPP)Cl/MWCNT] compared to the anchored Fe‐porphyrin on the graphene oxide [Fe(THPP)Cl/GO]. The study on the aerobic oxidation of alcohols in the presence of the supported Fe‐porphyrins proved that the addition of isobutyraldehyde as reducing agent in several portions during the catalytic reaction significantly increased the product yields. The separation and recovery of the nanocatalyst was simple, effective and economical in this green oxidation method and the supported catalyst can reuse at least eight times without significant loss of activity. [ABSTRACT FROM AUTHOR]

In this study, the as-received (AR) and nanoceria-doped (NCD) AlCrFeCoNi high-entropy alloy (HEA) coatings have been applied by the thermal spraying process. In this case, 0.5 wt.% of nanoceria was chosen to obtain NCD-HEA AlCrFeCoNi coating. Microstructural characteristics of the AR- and NCD-HEA AlCrFeCoNi powder and coatings were carried out using transmission electron microscopy, x-ray diffraction analysis, and field-emission scanning electron microscope equipped with energy-dispersive x-ray spectroscopy. Moreover, the microhardness profile and sliding wear behavior of NCD-HEA coatings were examined and compared with the AR-HEA coating. The results indicated that the NCD-HEA coating has a relatively denser microstructure than AR-HEA coating owing to the lower amounts of structural porosity and oxide stringers into the NCD-HEA coating structure. The results also demonstrated that the NCD-HEA coating has a higher sliding wear resistance compared with the AR-HEA coating. These findings were acquired due to the denser structure, higher hardness, and desirable dispersion of hard ceria nanoparticle reinforcements in the lamellar structure of NCD-HEA coating. [ABSTRACT FROM AUTHOR]

Carbonaceous nano-chlorapatites have attracted great attention for the remediation of heavy metal-contaminated environment. Herein, a novel biochar/graphene-supported chlorapatite (BC/G-ClAP) was successfully synthesized by a green method for the purpose of removing the Pb(II) from the water. The generated BC/G-ClAP was characterized by Scanning electron microscope (SEM) and transmission electron microscopy (TEM). It was found that biochar had the mesoporous structure with the layers of graphene on biochar surfaces and chlorapatites were distributed on the surface of biochar/graphene. BC/G-ClAP showed excellent remediation performance towards Pb(II) contaminated water, with the Pb(II) removing efficiency of 80.29%. The high remediation was due to the porous biochar/graphene with plenty of functional group have the strong adsorption for the Pb(II) ions and the chlorapatites showed the cation exchange with Pb(II) to form the stable Pb10(PO4)6Cl2. Therefore, this green synthesis method and the novel composites have a great potential for the application of remediation in the contaminated environment. [ABSTRACT FROM AUTHOR]

In order to solve the problem that separating zeolite 4A from solutions, we have synthesized Fe3O4/zeolite 4A magnetic nanocomposite by hydrothermal method. It is characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), Vibrating Sample Magnetometer (VSM), scanning electron microscope (SEM) and Brunner-Emmet-teller (BET). The XRD result shows that Fe3O4/zeolite 4A magnetic nanocomposite has a good crystal structure. It also shows that Fe3O4/zeolite 4A magnetic nanocomposite contains two phases of zeolite 4A and Fe3O4 MNP. The optimal sample (Z-2) was judged by the calculation of crystallinity. The successful combination of zeolite 4A and Fe3O4 MNP was visually observed through SEM technology. The functional groups of Fe3O4/zeolite 4A magnetic nanocomposite were characterized by FTIR technology. The TEM result shows that some Fe3O4 MNPs enter zeolite 4A, which further clarifies the microstructure of Fe3O4/zeolite 4A magnetic nanocomposite. N2 adsorption-desorption technique confirms that Fe3O4/zeolite 4A magnetic nanocomposite SBET is 55.3374 m2/g and Dave is 9.7128 nm. VSM result shows that Fe3O4/zeolite 4A magnetic nanocomposite magnetization is 18.4534 emu/g. Simulation experiment shows that Fe3O4/zeolite 4A magnetic nanocomposite exhibit a fast response to an external magnetic field. [ABSTRACT FROM AUTHOR]