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The European Union’s efforts to increase the share of renewable energy translate into a growing number of wind farms. Post-operation wind turbines become increasing waste. Recycling wind turbine blades is a challenge due to the materials used (composites) and high costs. The article examines the influence of recyclate from wind turbine blades (derived from mechanical recycling) on the image of topography and Lateral Force Microscopy (LFM) in atomic force microscopy (AFM). Upon adding the recycled material, an increase in surface roughness is observed despite its prior polishing. The Young’s modulus determined from force spectroscopy (AFM mode) indicated a small difference in values between the matrix and reinforcement areas. This proves the significant influence of the primary and secondary interphase on the properties of secondary composites, which is an area for further research. [ABSTRACT FROM AUTHOR]

Wet beneficiation is a primary process employed by mining companies for iron ore concentration. The moisture content in the ore is a result of this beneficiation process, in addition to inherent moisture within the mineral composition. The moisture content of iron ore is a crucial parameter that requires effective control to ensure safe handling and transportation operations. Surface plasma treatment of iron ore has been investigated as a method to enhance the hydrophobicity of ore particles, thereby reducing residual moisture and water reabsorption by the particles. The samples underwent treatment using argon plasma and cold hexamethyldisiloxane (HMDSO) plasma, leading to the formation of a thin, silicon-rich surface layer. The treatments were applied to both polished ore samples and fine powder samples. The plasma treatment resulted in a reduction in moisture content and water absorption. The reabsorption of water decreased to approximately 35% of the pretreatment values. Contact angle measurements demonstrated that all HMDSO-treated samples exhibited hydrophobic behavior, with contact angles ranging from 110° to 120°, while the untreated samples exhibited angles close to 0°. Furthermore, atomic force microscopy (AFM) topographic imaging revealed a granular structure in the thin films. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag-Nps) were grown on the surface of a p-type crystalline silicon (C-Si) substrate using electroless metal deposition. It was found that the Ag-Nps distribution on C-Si was controlled by the silver nitrate (AgNO3) concentrations. Atomic force microscopy observations revealed the formation of a continuous layer at high concentration. In contrast, a distribution of Ag-Nps with a spherical shape was obtained at lower concentration. The samples were also examined by optical microscopy under dark field illumination. The light reflected from Ag-Nps was obtained with different colors. This difference indicates a slight change in particle size. It is demonstrated that a silicon substrate with deposited Ag-Nps shows a significant decrease in reflectance and an increase of the absorption in the region from 200 to 800 nm. Moreover, the behavior of small Ag-Nps while interacting with light (absorbed or scattered light) is theoretically described using the Mie theory based on the Drude model. The introduction of silver nanoparticles on silicon surface is used to improve the efficiency of solar cells by reducing reflection and increasing the light absorption. [ABSTRACT FROM AUTHOR]

In this paper, the possibility of preparing silver nanostructures with a high area density of nanoparticles of various shapes by the ion beam sputtering (IBS) method, using a glancing angle deposition (GLAD) configuration, and subsequent irradiation with heavy ions, was tested. In the experiment, keV Ar+ ions were used for both IBS and bombardment. The prepared nanostructures were analyzed by RBS and microscopic methods of SEM and AFM. It turned out that IBS/GLAD makes it possible to create silver nanostructures (networks of individual silver nanoparticles), but only with relatively low areal densities (∼ 70 µm2). The bombardment led to changes in the porosity only after high ion fluences, but also to disruption of the nanostructures. Even so, the IBS method with GLAD configuration has been shown to be a promising way to prepare high-porosity nanostructures. Nevertheless, further experimental efforts will be needed to find the optimal technology. [ABSTRACT FROM AUTHOR]

During blending between the binders in hot mix recycling, two physical processes occur, namely blending due to diffusion and blending due to mechanical agitation. In the present study, an experimental approach is developed to observe these processes directly on the laboratory recycled asphalt mix samples. Atomic Force Microscopy (AFM) and Confocal Laser Scanning Microscopy (CLSM) are used as the probing tools. The binder concentration profile is estimated at different locations around the reclaimed asphalt pavement material (RAPM) aggregate. Diffusion is observed to be predominant in some of these locations, while, in some other locations, mechanical mixing is observed to be predominant. Assuming that pure Fickian diffusion is happening at those diffusion-spots, the coefficient of diffusion is estimated from the concentration profile at those locations. It is envisaged that the proposed approach would provide a microscopic perspective of the extent of blending during the recycling process. [ABSTRACT FROM AUTHOR]

The specific objective of this study was to investigate the effect of reactive ethylene terpolymer (RET) modification on bitumen properties at the nano and macro scales, as well as on porous asphalt (PA) mix properties. Measurements using the dynamic shear rheometer (DSR) and the bending beam rheometer (BBR) showed that RET modification of bitumen significantly improved the high-temperature properties, while intermediate- and low-temperature properties were similar to the base bitumen. The linear amplitude sweep (LAS) test conducted using the DSR showed that RET modification improved fatigue resistance. Consequently, chemical analysis and PeakForce™ Quantitative Nano-Mechanical™ (PF-QNM) atomic force microscopy (AFM) imaging were used to evaluate the microstructure and nanomechanical properties of the polymer modified bitumen (PMB) and the base bitumen before and after long-term ageing. The chemical analysis provided useful insights that complemented and helped to explain the AFM and rheology tests. The AFM results supported the LAS test findings in showing that RET modification improved the resistance of aged bitumens to cracking. The results of testing the PA mix showed significant improvements in moisture damage and ravelling resistance due to RET modification. [ABSTRACT FROM AUTHOR]

Abstract Fruits and vegetables are essential horticultural crops for humans. The quality of fruits and vegetables is critical in determining their nutritional value and edibility, which are decisive to their commercial value. Besides, it is also important to understand the changes in key substances involved in the preservation and processing of fruits and vegetables. Atomic force microscopy (AFM), a powerful technique for investigating biological surfaces, has been widely used to characterize the quality of fruits and vegetables and the substances involved in their preservation and processing from the perspective of nanoscale structure and mechanics. This review summarizes the applications of AFM to investigate the texture, appearance, and nutrients of fruits and vegetables based on structural imaging and force measurements. Additionally, the review highlights the application of AFM in characterizing the morphological and mechanical properties of nanomaterials involved in preserving and processing fruits and vegetables, including films and coatings for preservation, bioactive compounds for processing purposes, nanofiltration membrane for concentration, and nanoencapsulation for delivery of bioactive compounds. Furthermore, the strengths and weaknesses of AFM for characterizing the quality of fruits and vegetables and the substances involved in their preservation and processing are examined, followed by a discussion on the prospects of AFM in this field. [ABSTRACT FROM AUTHOR]

In the present work, the transport properties and morphology through tunneling structures were investigated, where the rough In2S3 thin films are the interfaces of these structures. In2S3 thin films were doped experimentally with Copper (Cu) and their morphology was studied by using the atomic force microscopic images at different temperatures (30, 55, 70, and 85 ° C). The results show that conductivity of the samples is strongly influenced by Cu doping content at different temperatures. Also, the transmission probability and current density of these samples were investigated numerically. The results show the maximum scattering component of transmission probability at temperature 30 ° C , for In2S3 thin films and 70 ° C , for CuIn2S3 thin films. By the results, increasing of the [Cu/In] molar ratios will lead to an increase in the transmission probability and current density of these thin films. [ABSTRACT FROM AUTHOR]

Solid-state Pb(II) ion selective electrodes were developed, which are based on 3,3-disubstituted 1-acylthioureas as ionophores and use PVC membranes. 1-Benzoyl, 1-(2-furoyl), 3,3-diethyl and 3,3-diphenyl were the substituent groups on the thioureide core. The analytical parameters for the constructed electrodes were studied. The electrodes based on 3,3-diethyl substituted thiourea derivatives showed better analytical response to Pb(II) ions with suitable sensitivity and an average lifetime of more than 30 days. Cu(II), Hg(II) and Ag(I) ions were interfering species during Pb(II) detection. Scanning electron microscopy and atomic force microscopy micrographs of the activated sensing membranes revealed morphological changes, which have been associated with the performance of the sensors. The studies have suggested that the detection of few large size particles or aggregates at the membrane surface are responsible for inadequate functioning of the prepared electrodes. This pattern was mainly observed for the sensing membranes based on 3,3-diphenyl groups as substituents and is related to unfavorable steric and electronic factors. Furthermore, X-ray photoelectron spectroscopy profiles S2p and Pb4f supported chemically the analytical response displayed for the four membrane systems. The X-ray photoelectron spectroscopy results combined with scanning electron microscopy and atomic force microscopy studies shed light on the working mechanism of the studied electrodes. [ABSTRACT FROM AUTHOR]

The present work is focused on the eco-friendly electrodeposition of nanocrystalline palladium on the copper substrate using an ammonia complex for the replacement of gold. The detailed study on the electrodeposition of palladium prepared from ammonia complex and solution characteristics such as current efficiency and thickness of the film growth per hour was evaluated using Faraday's law of electrolysis, and the quality of the deposits was observed by Field Emission Scanning Electron Microscopy (FESEM). The crystal structure orientation of the crystal and lattice parameters were analysed by X-ray diffraction and crystal sizes were calculated using the Debye–Scherrer equation. The deposits produced from gelatin-containing electrolyte showed the lowest crystal size which indicates that grain refinement was assisted by additives. The microstructures of the palladium deposits were determined by FESEM and the surface morphology of the palladium deposits was evaluated using AFM. The elemental composition and oxidation state of the palladium deposits were investigated by XPS. These results revealed the presence of additives giving smooth uniform homogenous surface morphology. Hence, gelatin served as a grain modifier. [ABSTRACT FROM AUTHOR]

Ferroelectric polymer PVDF possesses different polymorphs. Solution-processed thin films crystallize mostly into the paraelectric α-phase. From α-PVDF, the electroactive phases β-, γ-, δ-PVDF can be achieved by further treatments. For instance, δ-PVDF, also known as αp-phase, can be obtained by electro-forming. In this work, we study the α-PVDF surface morphology using atomic force microscopy through a high-resolution image at the sub-nanometre scale. We go through the ferro- and piezoelectric properties of the electro-formed δ-PVDF thin films and we present an electro-mechanical characterization in high-fields regime, for studying the non-linear electrostrain behaviour, and in low-fields regime, for extracting the piezoelectric coefficient. The capability of atomic force microscopy to investigate surfaces at sub-nanometre scale is applied for a direct observation of polymer chains within the crystalline lamellae at the unit-cell length characteristic. [ABSTRACT FROM AUTHOR]

This review article outlines the set of observations and findings from some previous publications that addressed the different techniques used for understanding and evaluating metallic corrosion and its retardation by using different inhibitors. The main emphasis is on the different electrochemical characterization techniques and surface analysis methods used for studying corrosion inhibition. A brief about polarization, electrochemical noise, electrochemical frequency modulation, impedance study for electrochemical characterization techniques and contact angle, scanning electrochemical microscopy, atomic force microscopy, and scanning electron microscopy methods, x-ray photoelectron spectroscopy, etc. are included for a better understanding of corrosion inhibition phenomenon. The literature suggests that corrosion of metals and alloys is effectively controlled by the use of inhibitors having heteroatoms such as nitrogen, oxygen, or sulfur. In this article, the papers from the last sixteen years i.e., from 1996 to 2021 are considered to get an insight into current methods for retarding corrosion. General introduction, mechanisms of corrosion along with factors affecting corrosion has also been described in the present article. Data collected in this review will be advantageous for researchers to get an idea about the basics and the recent techniques used in corrosion study. [ABSTRACT FROM AUTHOR]

In this study, a novel measuring instrument named defocus atomic force microscope (DeF-AFM) is presented. A Gaussian beam intensity measuring method is proposed for this optical pickup unit (OPU)-based AFM. Only partial components inside the OPU such as the laser diode, the objective, and the photodiode IC (PDIC) are required for this method. The displacement of the cantilever can be acquired by analyzing the exponential intensity change, which is along the optic axis of the laser, reflected to the PDIC. A support controller for the DeF-AFM is also designed and developed. The dynamic measuring ranges of this AFM in X, Y, and Z-axis are designed to be 12,000 nm, 12,000 nm, and 1400 nm, respectively. The horizontal and the vertical resolution are approximately 3.3 nm and 0.34 nm, respectively. The spatial resolution of the DeF-AFM is also verified by resolving the single atomic layer of the highly ordered pyrolytic graphite (HOPG). [ABSTRACT FROM AUTHOR]

The results of the study of high conducting areas at the interface between ferroelectric and insulating oxides Ba0.8Sr0.2TiO3/LaMnO3 are presented. It is shown that the electrical resistance of the heterostructure decreases significantly with cooling and exhibits metallic behavior at low temperatures, and its properties depend on magnetic field application. The effect of green (514 nm) and infrared (1028 nm) pulsed laser light on Ba0.8Sr0.2TiO3/LaMnO3 heterostructure electrical resistance leads to a decrease in the electrical resistance. It is assumed that the effect is related to polarization screening in the ferroelectric film, and atomic force microscopy studies confirm this hypothesis. [ABSTRACT FROM AUTHOR]

A pH measurement of water by disposable, high accuracy, and semi-transparent BN/Ag nanocomposite thin film sensors manufactured by thermionic vacuum arc technique have been investigated. According to the results, columnar, crack-free, well connection among oriented grains and dense particles were growth on the BN/Ag electrode coatings. It is evident from the electrochemical impedance spectroscopy, ohmic resistance, R value is pH-sensitive, and it was increased by decreasing pH. As a results, disposable and high accuracy BN/Ag nanocomposite thin film sensors have been very good worked between pH 6.64 and pH 7.83. This range is very good fit the range of pH values of the body liquids and drinking water. And, manufactured sensor worked in the range with high accuracy. [ABSTRACT FROM AUTHOR]

The adverse environmental effects of synthetic fibers have forced researchers to use natural fibers in composite preparation. Pinus Roxburghii Needles (PRNs) are widely available in the hilly region of Uttarakhand state, India. Utilizing the fiber extracted from PRNs as reinforcement in bio-composite preparation can reduce synthetic fiber and emphasize the use of natural resources. In this study, we extract the Pinus Roxburghii Fibers (PRFs) from PRNs using the water retting method. Their physical, chemical, thermal, and morphological aspects were investigated and reported. The average diameter and density of the extracted PRFs were obtained as 145 ± 17.36 μm and 1020 ± 20.27 kg/m³, respectively. The chemical analysis revealed that the extracted PRFs contain 58.30% cellulose content. Thermal stability and maximum degradation temperature of the extracted PRFs were assessed using thermogravimetric analysis (TGA) and found to be 225°C and 355.84°C, respectively. Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscope (AFM) were used to study the surface morphology and surface roughness of PRFs, respectively. Further, the FTIR analysis of the extracted PRFs confirmed the presence of different functional groups of cellulose, hemicellulose, and lignin. The crystallinity index (43.52%) and crystal size (4.03 nm) of the extracted PRFs were determined using X-ray diffraction (XRD) analysis. [ABSTRACT FROM AUTHOR]

The aim of this work is to extract and characterize the new natural Artocarpus altilis bark fiber (AABF). The density of AABF is identified as 986 kg/m3 and chemical analysis confirmed cellulose 60.45 wt%, hemicellulose 10.73 wt%, and lignin 15.28 wt%. Single fiber tensile test indicates the tensile strength as 257 MPa with strain rate of 3.54%. The presence of chemical functional groups in the fibers was identified by Fourier transform infrared (FTIR) analysis. X-ray diffraction (XRD) analysis ensured that the Crystallinity index (CI) as 52.2% and crystalline size (CS) 10.26 nm. Thermo Gravimetric analysis (TGA) shows the thermal stability of AABF as 228°C with kinetic activation energy 77.018 kJ/mol. Scanning Electron Microscopy (SEM) analysis investigates the surface morphology and its roughness parameters are analyzed through Atomic Force Microscopy (AFM) analysis. The results obtained revealed that AABFs are suitable for reinforcement in polymer composites and that can be applied for lightweight applications. [ABSTRACT FROM AUTHOR]

Areca Catechu Fiber (ACF) is a waste product, which is expelled from tobacco industries, and in some cases, it is used as fuel. However, it is rich in fiber. This study addresses the characterization and physical and chemical properties of ACF. It is rich in cellulose (63.24 wt %) content, which seems to be higher in wt % when compared with other natural fibers. The fibers are characterized by using scanning electron microscope, Fourier transform infrared spectroscopy, atomic force microscope, X-ray diffraction analysis, thermo gravimetric analysis, and differential scanning calorimetry. The density of the fiber is noticed as 1.34 g/cc, and it provides the better replacement for synthetic fiber. Since the wax content is less (0.34 wt %), it provides better adhesion between fiber and resin interface. Therefore, ACF could be a better solution for an eco-friendly composite product. [ABSTRACT FROM AUTHOR]

Chitosan vanillin Schiff base (ChVSB) was synthesized by condensation reaction between chitosan and vanillin and characterized by elemental, spectral, thermal, and scanning emission microscopic (SEM) analysis. The inhibition performance of ChVSB for mild steel corrosion was evaluated using electrochemical techniques and showed a better inhibition of 91.1% for 1500 ppm. The inhibition is attributed to the formation of protective layer on the metal surface which was confirmed by Atomic force microscopic technique and contact angle measurements. The scale inhibiting potential of the ChVSB for Calcium carbonate scale was investigated by static experiments and SEM analysis. The results exhibited the better scaling efficacy of ChVSB exhibiting 83.34% at the temperature of 70 °C and SEM analysis confirmed the morphological changes occurred in presence of ChVSB. [ABSTRACT FROM AUTHOR]

Chitosan vanillin Schiff base (ChVSB) was synthesized by condensation reaction between chitosan and vanillin and characterized by elemental, spectral, thermal, and scanning emission microscopic (SEM) analysis. The inhibition performance of ChVSB for mild steel corrosion was evaluated using electrochemical techniques and showed a better inhibition of 91.1% for 1500 ppm. The inhibition is attributed to the formation of protective layer on the metal surface which was confirmed by Atomic force microscopic technique and contact angle measurements. The scale inhibiting potential of the ChVSB for Calcium carbonate scale was investigated by static experiments and SEM analysis. The results exhibited the better scaling efficacy of ChVSB exhibiting 83.34% at the temperature of 70 °C and SEM analysis confirmed the morphological changes occurred in presence of ChVSB. [ABSTRACT FROM AUTHOR]

Sustainable Zoffa extract solution provides organic molecules with structures including heteroatoms, aromatic rings, and polar groups, which play an important role in the adsorption and inhibition process on metal substances in corrosive environments. The main components in Zoffa extract solution, such as phenylacetaldehyde, myrtenol, pinocamphone, and isopinocamphone, can easily be adsorbed on the ASTM/A36 steel surface and appropriately control its corrosion rate in 1 M HCl at different temperatures. The adsorption process was characterized using FTIR, UV/vis, fluorescence SEM, atomic force microscopy (AFM), and the contact-angle technique. The inhibition performance was evaluated using chemical methods, such as mass loss (ML) and hydrogen evolution (HE), and electrochemical methods, such as potentiodynamic Tafel polarization (PTP), electrochemical impedance spectroscopy (EIS), cyclic polarization sweep (CPS), and the Mott–Schottky technique (MST). The PTP explained the mixed inhibition effect of the Zoffa extract with predominantly cathodic inhibition. A Zoffa concentration of 1500 ppm provided an average inhibition protection of 94.68%. The Zoffa molecule was adsorbed on the electrode surface according to the Langmuir isotherm. Thermodynamic parameters involving E*, ΔH*, ΔS*, and ΔG* were calculated using Arrhenius and transition-state equations. The quantum parameter was theoretically estimated using the density-functional-theory method with 6-311++ G(d,p) as the basis function set to elucidate the correlation between the molecular structure of the inhibitor and its inhibition performance. [ABSTRACT FROM AUTHOR]

The mathematical model of an AFM nonuniform probe in the modified couple stress theory is derived here. The analytical method is proposed to design the configuration of the AFM probe satisfying the integer-multiples relation among frequencies. The varying cross-section of the probe is tuned to match the specific requirement. One discovers two similarity conditions such that the integer-multiples relation is kept in spite of the size-dependency parameter. Moreover, the relations among the natural frequencies, the effective spring constant and the geometry parameters are discovered. The specific frequencies and spring constant can be obtained by tuning the probe parameters via the relations. [ABSTRACT FROM AUTHOR]

In the present work, bio-nanocomposite films of sodium alginate/polyvinyl alcohol (SA/PVA) blend with different loadings of boehmite alumina (BA) nanoparticles were developed via the film-casting technique. The bio-nanocomposite films obtained, containing boehmite alumina nanoparticles, are highly transparent and eco-friendly. The morphological characterization, by using TEM, AFM and SEM, indicate the fact that the BA nanoparticles showed a homogeneous dispersion at low BA loading, with rod-like features and plates with cubic crystal shapes morphology. Conversely, BA agglomeration was observed at higher BA loading. The mechanical properties indicate improvements in the tensile strength and elongation-at-break and flexibility in the 3 wt% BA nanoparticles loading. This (3 wt%) is stable with homogeneous dispersion of BA nanoparticles in the SA/PVA blend matrix, which is confirmed by SEM and TEM analysis. Additionally, the contact angle of the blend matrix was observed to be 34.7° and with the incorporation of boehmite alumina (BA) of between 3 to 9 wt % to the hydrophilic blend matrix, the results in contact angles of the nanocomposite films in increasing hydrophobic order of 47.9–67.9°, respectively. Furthermore, the incorporation of BA nanoparticles shows that the SA/PVA blend matrix have desirable thermal stability. From the present study, the novel ternary SA/PVA/BA bio-nanocomposite films could be a potential candidate to be used in the fields of biomedical (such as wound healing) and packaging applications. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study was to evaluate the surface properties of four composite materials with different organic contents and Streptococcus mutans (S. mutans) adhesion to the surfaces after 4 h. TCD-based (CT; Charisma Topaz), Bis-GMA-based (ESQ; Estelite Sigma Quick), UDMA-based (GA;G-aenial Anterior), ormocer-based composites (AF;Admira Fusion) were selected. Polystyrene was used as a control group. Fifteen cylindrical specimens (10 mm diameter × 2 mm depth) were prepared for each group. Surface roughness (SR) was investigated with AFM. Hydrophobicity and surface free energy (SFE) was determined by the sessile drop method. Early adhesion of S. mutans on the materials were evaluated by optical density readouts on a spectrophotometer. Surface morphology and S. mutans bacterial adhesion (SMBA) were examined using SEM. Data were analyzed by ANOVA, post-hoc Dunnett (p < 0.001), and Tukey tests (p < 0.05).Spearman's rho coefficient was used to investigate the correlation between SR and SMBA. There was a statistically significant difference between the test groups in terms of SR (p < 0.05).AF showed the highest roughness value while ESQ showed the lowest. No statistically significant difference was observed between the test groups in terms of total SFE and hydrophobicity (p > 0.05) while a statistically significant difference was obtained between the test groups in terms of surface SMBA (p < 0.05).The highest SMBA was observed in GA while ESQ showed the lowest. There was a significant correlation between SMBA and SR in the AF (r = 0.929; p = 0.001), CT (r = 0.976; p = 0.001) and ESQ(r = 0.731; p = 0.040).There is a correlation between the SR of composite materials with different organic contents and SMBA. It can be stated that the Bis-GMA based composite material has clinically acceptable physical properties due to its low SR and S. mutans adhesion. [ABSTRACT FROM AUTHOR]

Zirconium diselenide thin films were electrodeposited on the stainless steel substrates for various pH values ranging from 2.0 to 3.5. The deposition potential range suitable for the deposition has been optimized using cyclic voltammetry (CV). The X-Ray Diffraction (XRD) results confirm that the thin films produced were polycrystalline in nature with hexagonal structure peak at 2θ = 43.8° (003) of ZrSe2. The surface morphology of the film indicate, as the pH was increased the grain size of the film become larger due to agglomeration. The direct band gap energy of the films was found to be in the range of 1.77–1.83 eV. [ABSTRACT FROM AUTHOR]

The effect of strontium (Sr) doping on structural, morphological and optical properties of bismuth ferrite (BFO) thin films containing various doping concentrations of Bi(1−a)SraFeO3 (a = 0.00, 0.01, 0.03, 0.05, 0.10) was synthesized using a spray pyrolysis technique. Based on the experimental results, EDAX confirmed the existence of bismuth, ferrous and strontium particles in the developed thin films. The XRD results confirmed a decrease in the size of the crystals after Sr substitution at Bi site. The FESEM results confirmed the reduction of particle size with dopant addition. The BFO films exhibited a cone-type grain growth with an increase in surface roughness with Sr dopant. The results obtained from UV–Vis spectrophotometer show an increase in energy bandgap for various concentrations of the dopant. The results obtained from the characterization revealed that Sr-doped BFO is a very good candidate for gas sensor applications. [ABSTRACT FROM AUTHOR]

Abstract Biosynthesis of silver nanoparticles (AgNPs) has been performed using various sources including plants and fungi. Sargassum swartzii is an alga that has a vast spectrum of biological activities and is predominantly found on the Indian coasts. In this study, AgNPs was biosynthesized using S. swartzii and evaluated for its antibacterial potency against Escherichia coli (ATCC 25922). The synthesized nanoparticles (NPs) were imaged using TEM analyses and found to be predominantly spherical and crystalline with size around 20–40 nm. The Zeta sizing analysis revealed mean particle size to be 40.4 nm. The XRD analysis revealed the particles are crystalline nature and average size around 54 nm. The biosynthesized AgNPs were used against treating E. coli and it was found to cause a considerable amount of deterioration to the microbes when observed under AFM and FE–SEM. The study revealed the significant antibacterial activity of the synthesized AgNPs due to extensive membrane damage.  [ABSTRACT FROM AUTHOR]

The characteristics of a poly(ethylene-co-vinyl acetate) (PEVA) film formed by spin coating process and ion beam (IB) irradiation was investigated with irradiation times. A physicochemical analysis was used to analyse the suitability of the PEVA film as a uniform liquid crystal (LC) alignment layer. Atomic force microscopy (AFM) revealed an increased surface roughness after IB irradiation. X-ray photoelectron spectroscopy (XPS) analysis showed IB irradiation broke the polymer branches and increased the oxygen concentration and bonding on the surface. These derived the strong Van der Waals forces and dipole-dipole interactions between the PEVA surface and LCs. The IB irradiation generated surface anisotropy on the PEVA film and unidirectional LC alignment was achieved. Polarised optical microscopy (POM) and pre-tilt angle measurements were carried out to show the uniform LC alignment. The transmittance curve exhibited a high optical performance. These results show the promising capabilities of IB irradiated PEVA film as an alignment layer in LC displays. [ABSTRACT FROM AUTHOR]

In this work, functional scaffolds based on electrospun chitosan nanofibers are unprecedentedly studied in terms of their force cell adhesion response. To prove cell compatibility of this biomaterial, chondrocyte interactions are investigated using atomic force microscopy in which a single cell is fixed to the cantilever and approached to the chitosan mat for a given contact time. Then, the cantilever is retracted and cell interactions are studied. Force jumps distribution for cell detachment is described and the adhesion energy is determined comparing nanofiber mats with homogeneous films and a BSA coated surface as control. Force adhesion on chitosan films, equals 460 ± 150 pN, is found slightly higher than on porous fiber mats (410 ± 135 pN) indicating that more cell-substrate bonds could be formed on a flat contact surface for a contact time of 60 s. The same trend was observed for a contact of 120 s between the cell and the substrate. The adhesion on hydrophilic chitosan surface at t = 60 s, is much larger than on the control surface (210 ± 90 pN) due to its positive character and ability for H-bond stabilization. [ABSTRACT FROM AUTHOR]

Cryptomelane (α-MnO2) nanoparticles synthesis was achieved via a Sol-Gel route in mild conditions. XRD analysis showed that the α-MnO2 phase was of high purity and crystallized in the monoclinic space group I2/m, with 12 nm average crystallite size (D). After interaction with an organic pollutant (Phthalic acid, PA), excepting the pronounced decrease in β angle, α-MnO2 cell parameters slightly changed, probably resulting from leaching of K+ cations. Adsorption isotherm of PA on α-MnO2 nanoparticles was fitted in L2 type Langmuir model. Accordingly, an outer-sphere PA-Mn surface complex was suggested. Further, the mineral oxide exerted a low activity in the decarboxylation of PA. Raman analysis illustrated the major bands, of α-MnO2, and their evolution after adsorption indicated the effect of PA on the phase structure, as revealed by the XRD Rietveld refinement. AFM analysis showed stick shaped nanoparticles with D = 15 nm, but the interaction with PA induced aggregation. [ABSTRACT FROM AUTHOR]

Since in the approximation made by the modeling and simulation of the manipulation, the accuracy plays an important role so it makes researchers to eliminate simplifications and limitations. Damping properties of the biological particles and consequently loading history of them is one of those simplifications considered until now. The other simplifying assumption is the ignorance of the oscillatory drag during modeling of the manipulation in a liquid environment elimination of which results in more precise modeling. To achieve this goal and increase the accuracy of the modeling in this paper, particles are considered viscoelastic and the oscillatory drag is added to the Stokes drag. To do so, several viscoelastic contact models are developed to choose the better suited model for biological particles. On the other hand, to modify the prediction of the particle and tool's behavior, ignored rotation about z axis is also considered. Obtained results show that considering particles viscoelastic leads to the decrease of the critical force in comparison with the elastic state. This is due to the decreasing of the deformation acceleration based on the particle's damping. These differences are about 29% for sliding of the tip on the particle, 8% for sliding of the particle on the substrate and 22% for rolling. Besides, application of the oscillatory drag force about 1.7nN leads to increasing of the drag which can be ignored in the modeling but in the case of high precision modeling this drag can be take into consideration. Therefore, it can be said that considering viscoelastic properties of the particle increases the accuracy of the modeling and simulation and as a result behavior prediction of the particles under manipulation. [ABSTRACT FROM AUTHOR]

The aim of this present investigation is to improve the properties of natural fiber from red banana peduncle plant by alkali treatment for the first time. The main objective of this paper was to study the physico-chemical, thermal, and mechanical properties which are chemically modified by alkaline treatment of red banana peduncle fiber (ARBPF), which is used as a reinforcement in the polymer matrix and finally to make an end product for various industrial applications. The result indicates that cellulose content was improved in ARBPF when compared to untreated red banana peduncle fiber which is proved through X-ray diffraction (XRD) studies recording high crystalline index in fibers. The thermal property of ARBPF also exhibiting good thermal stability was observed by thermo-gravimetric analysis (TGA), atomic force microscopy (AFM) analysis confirmed that the surface of the fiber is rough. [ABSTRACT FROM AUTHOR]

The development of biofouling is a major problem for marine industries. The conception of antifouling and fouling release coatings, with controlled physical-chemical properties is a promising strategy. Among them, amphiphilic systems, such as those composed of a hydrophobic polydimethylsiloxane matrix and a hydrophilic polyethyleneglycol additive are the most efficient and up to date. Despite their effectiveness, these systems are questioned due to the petrochemical origin of PDMS. The aim of this project was to substitute the PDMS matrix with a biopolymer, poly(3-hydroxybuyrate-co-3-hydroxyvalerate) and to improve its anti-adhesion properties through the elaboration of an amphiphilic system, via the addition of PEG or PHBHHx-b-PEG copolymer. The results, including the physico-chemical properties of PHBHV based coatings and static adhesion tests on a marine bacterium, Bacillus 4J6 and a diatom, Phaeodactylum tricornutum are compared with those of PDMS and PEG-modified PDMS coatings. Real antiadhesion activity was obtained for the PHBHV/PHBHHx-b-PEG system for a promising eco-friendly strategy. [ABSTRACT FROM AUTHOR]

The production of materials using synthetic fibers is a strong contributor to carbon emissions and waste. Because of growing environmental consciousness, natural fibers act as a substitute for synthetic fibers due to their renewable, eco-friendly and bio-degradable nature. Natural cellulose fibers are newly identified from the sources of Albizia Lebbeck fibers (ALF). This study is intended to understand the characteristics of ALF extracted from the bark of the Albizia Lebbeck and its physicochemical properties. The structure of the fibers was analyzed by FT-IR and X-ray diffraction. Cellulose content (72.59 wt.%), density (905 kg/m3), and crystallinity index (52.99%) properties were identified in the AL fibers, and thermal studies using Thermo Gravimetric Analysis and Derivative Thermo Gravimetric analysis revealed that the maximum degradation temperature is 353.37°C with kinetic activation energy of 89 kJ/mol. From the results, it is concluded that the properties of ALFs guaranteed that it could be an alternative material as new reinforcement as green composites in the manufacturing and automobile industries. [ABSTRACT FROM AUTHOR]

The size-dependent effect on the dynamic behavior of the structures in the order of microns or sub-microns is significant. The mathematical models of the AFM probe subjected to van der Waals force based on three different theories are presented and solved. The numerical results by the perturbation method in modified strain gradient theory and the experimental results are very consistent. The resonant frequency-material length scale parameter relation relationships among the three models are discovered. According to the relationships, the resonant frequencies can be easily and accurately predicted. [ABSTRACT FROM AUTHOR]

Emerging trends toward miniaturization and growing demands have led to fabricate the nanofeatures size product for electronics, robotics, aeronautics, biomedical, automobile, and Bio-MEMS sectors. This article investigates an approach to downsize the resolution limits of EDM to nanometric scale, bridging the gap between micro and nanoscale machining considering the thermal impact of electrical discharge. Nano-EDM technology may offer nanosized features, for instance, complex 3D nano-grooves, nanocavities, nanopores, nanotools, nano-painless needles for drug delivery, etc. It is somewhat difficult in any other non-conventional process for electrically conducting alloys having poor machinability. The article identified research issues and perspective solutions for the advancement of nano-EDM technology. The research gap, constraints, and opportunities for future research activities are critically examined through state-of-the-art knowledge. The characterization of features that can be made only by nano-EDM is also highlighted along with their innovative application. The impact of advancements in pulse power technology upon the realization of nano-EDM is briefly reviewed. Moreover, various numerical and simulation approaches along with recent optimization techniques have been demonstrated at the end to understand the continuum mechanics of nano-EDM at the atomic level. Finally, promising future research directions in nano-EDM are emphasized and highlighted. [ABSTRACT FROM AUTHOR]

Pyrazinecarboxylic acid (PCA) was examined as a potential corrosion inhibitor for mild steel (MS) in 0.5 M HCl environment. The methods of electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), as well potentiodynamic (PD) polarization were utilized. Furthermore, atomic force microscopy (AFM) and quantum chemical calculations were utilized. PD polarization curves demonstrated that PCA exhibited mixed inhibitor behavior. Scanning electron microscopy (SEM) offered the creation of an adsorptive layer on the surface of MS which prevented the steel against corrosive specimens. Furthermore, density functional theory (DFT) presented good agreement with electrochemical experimental results. The adsorption equilibrium constant ( K ads ) value was calculated to be 3.704 × 104M−1 which was related to a high proportion of inhibitor on the surface. In the presence of 1.0 mM PCA, inhibition efficiency was determined as 95.2% from EIS results. [ABSTRACT FROM AUTHOR]

In this study mixture of coconut shell and coir was used for Cr (VI) removal from synthetic wastewater and statistical tool Response Surface Modeling (RSM) was applied to optimize process parameters. The solution pH (2–6), reaction time (20–100 minutes) and adsorbent quantity (0.03–0.2 g) was optimized to find the maximum response of Cr (VI) removal using statistical Box-Behnken design (BBD) software. The equilibrium data obtained by the batch experiment were analyzed by ANOVA and found fitted in a second-order polynomial equation through multiple regression analysis. The optimum value of pH, adsorbent quantity and reaction time for 99% of Cr(VI) was found as 2, 0.1 g and 100 minutes, respectively. By using non-linear regression method it was found that Freundlich isotherm and Pseudo-second-order kinetic with high correlation coefficient (R2), low Chi-square (χ2) and root mean squares errors (RMSE), best describe the adsorption of Cr (VI) on mixture of coconut shell and coir (MCSC) surface. Positive enthalpy (ΔH°) and negative Gibbs free energy (ΔGo) values confirm the endothermic and spontaneous nature of adsorption process. Pre and post adsorption phenomenon was confirmed by characterization of adsorbent using AFM, FTIR, SEM, and EDX analysis. The adsorbent MCSC has regenerative property and can be reused 3–4 times after treating with alkaline medium (0.2 N NaOH) and offered more than 60% removal of Cr (VI) at the fourth cycle. It can be inferred based on this study that MCSC is an effective adsorbent for Cr (VI) removal and can be used on an industrial scale for social and environmental benefit. Novelty statement An agriculture waste mixture of coconut shell and coir (MCSC) without the addition of any chemical reagent, was used for Cr(VI) removal. As per literature survey and best of our knowledge, the adsorbent MCSC has not been reported for Cr (VI) removal. In the previous study, authors reported either coconut coir pith or coconut shell or coconut charcoal as adsorbent for Cr (VI) removal. The adsorbent MCSC is efficient even at very low doses (0.1 g) as compared to the reported adsorbent. In this study, several statistical tools have been used for the optimization of adsorption parameters. Besides, the material has been characterized before and after adsorption by different sophisticated methods like AFM, SEM-EDX, and FTIR. A desorption study has also been conducted using 0.2 N NaOH medium showing its regenerating capacity up to four-cycle. [ABSTRACT FROM AUTHOR]

Modification of semiconductor thin films by Swift Heavy Ion (SHI) beam irradiation is a unique technique for property improvement. In the present investigation, Cadmium Zinc Telluride (CZT) thin films of thickness 100 nm are deposited on glass substrates by the thermal evaporation method. These films are irradiated with 100 MeV Ni ion beams at a fluence of 1×1012 ions/cm2 and 5×1012 ions/cm2. The SHIinduced surface modifications are studied by Atomic Force Microscopy (AFM). The structural properties are investigated using X-ray diffraction (XRD) technique. Optical characterization is carried out using UV–Vis spectroscopy. The SHI irradiation on CZT films results in grain fragmentation. Phase transformation and widening of bandgap is also observed after SHI irradiation. The SHIinduced property modifications are explained in the framework of 'coulomb explosion and thermal spike model'. [ABSTRACT FROM AUTHOR]

The inhibition effect of extracts obtained from the commercially insignificant, perennial and overgrowing plants in Tunisia such as Dwarf palm (DP) and Cynara cardunculus (CC) plants leaves against St37 steel corrosion in 15% H2SO4 has been investigated with weight loss experiments (WL) and classical electrochemical methods. The investigations were conducted at the various concentrations of studied extracts, experiment temperature and time. The obtained results were compared with electrochemical impedance spectroscopy (EIS), dynamic electrochemical impedance spectroscopy (DEIS) and surface imaging method outcomes. The results showed that DP and CC extracts exhibit good corrosion inhibitor for St37 steel in 15% H2SO4 solution. From all applied methods, DP extracts approximately showed better inhibition efficiency than CC. The adsorption of the inhibitors was found to obey the Langmuir adsorption isotherm. Results of infrared spectroscopy (FTIR) and physical electronics spectrometry (XPS) analysis strengthen the authenticity of other experimental results by proving that the extract molecules have bonded with the surface of the St37 steel. [ABSTRACT FROM AUTHOR]

This study was aimed at understanding the characteristics of Celosia argentea fiber (CAF) and its physicochemical properties. The physicochemical properties of CAF were analyzed by FT-IR, XRD, TGA, SEM, and AFM analysis. Cellulose content (64.34wt.%), density (843 kg/m3) and crystallinity index (52.54%) properties were identified in the CAF while the thermal studies performed by TG and DTG technique revealed that the maximum degradation temperature is 324°C with a kinetic activation energy of 61.393 kJ/mol. From the results, it is evident that the CAF could be one of the future reinforcement materials for green composites applications. [ABSTRACT FROM AUTHOR]

In the present work, gallium arsenide samples implanted with 325 keV Mn+ ions for the fluence of 5×1015, 1×1016 and 2×1016 ions cm-2, have been investigated using Raman scattering and Atomic force microscopy measurements. The sample implanted with the fluence of 1×1016 ions cm-2 was further irradiated using 5 MeV Si++ ion beams for the fluence of 1×1016 ions cm-2 at a substrate temperature of 350°C for recrystallization. Raman peaks obtained at 293.51 and 269.35 cm-1 were assigned to longitudinal optical (LO) phonon mode and transverse optical (TO) phonon mode of gallium arsenide, respectively. The shift in the Raman peaks towards higher wave-number with respect to ion fluence indicated the presence of residual compressive stress within the samples. The Mn and (MnAs) like mode were observed after implantation. The additional mode like GaMn was also seen in sample after irradiation with 5 MeV Si++ ions. The composition of manganese atoms in gallium arsenide estimated from the Raman spectra for the ion fluence 5×1015, 1×1016 and 2×1016 ions cm-2 were found to be 0.74%, 1.40% and 2.80%, respectively. The Phonon coherence length estimated from the Phonon Confinement Model by fitting the LO phonon signal was found to increase from 39.40 to 47.10nm with respect to ion fluence. AFM images of non-implanted sample showed the smooth micrograph with root mean square surface roughness of 0.41 nm. After implantation, the different sizes of clusters were observed on the surfaces of GaAs. The shape and size of the clusters were found to depend on the ion fluence. [ABSTRACT FROM AUTHOR]

The objective of this examination is to characterize the fibers from the bark of Ficus racemosa fibers (FRF). FRF is composed of cellulose (72.36 wt. %), hemicellulose (11.21wt. %), lignin (10.45 wt. %), and has a density of 895 Kg/m3. The Differential thermogravimetry (DTG) shows that the maximum degradation peak temperature was attained at 310.56°C. The presence of a chemical group in the fibers was revealed through Fourier transform (FT-IR) analysis. The crystalline structure was characterized by X-ray diffraction (XRD). For surface morphology, Scanning electron microscopy (SEM) and Atomic force microscopy (AFM) were used. The obtained results indicated that FRFs are suitable fibers for polymer composite as reinforcement. [ABSTRACT FROM AUTHOR]

The phytochemical components of the methanol extract of Liriope platyphylla (L. platyphylla) leaves were identified using UHPLC, and their antioxidant activities were studied. The impact of the L. platyphylla extract on the corrosion of mild steel by 1 M H2SO4 was assessed using electrochemical and gravimetric techniques. L. platyphylla exhibited concentration-dependent corrosion protection activity through a mixed-mode adsorption process, as revealed by polarization studies. Impedance measurements indicated the development of a protective film of the inhibitor, which was confirmed by morphology studies at the micro level with scanning electron microscopy (SEM) and at the nano level with atomic force microscopy (AFM). Fourier transform infrared (FT-IR) studies also confirmed the adsorption of the inhibitor film onto the mild steel surface. [ABSTRACT FROM AUTHOR]

We conducted an in situ study on CFRP fracturing process using atomic-force-microscopy-based stress-sensitive indentation. Tensile stress distribution during fracture initiation and propagation was directly observed quantitatively. It led to a discovery that previously believed catastrophic fracture of individual carbon fiber develops in a controllable manner in the polymer matrix, exhibiting 10 times increase of fracture toughness. Plastic deformation in crack-bridging polymer matrix was accounted for the toughening mechanism. The model was applied to explain low temperature strength weakening of CFRP bulk material when matrix plasticity was intentionally 'shut down' by cryogenic cooling. [ABSTRACT FROM AUTHOR]

Scanning ion conductance microscopy (SICM) have attracted great attention as one of the most promising candidates for imaging soft and delicate biological samples. In this review, firstly, up to date research on investigating samples' surface properties using SICM are demonstrated. In surface charge part, as the bias is varied, a polarity-dependent ion current and surface-induced rectification can help SICM to create images of surface charge. In dynamics of living cells part, SICM allows both non-labeling and non-contact during the measurement and performs the best smong fluorescent microscopy and AFM in visualizing dynamics of living cells. In surface morphology part, four examples are demonstrated to show SICM's power. Secondly, combinations with mature technology such as scanning electrochemical microscopy (SECM), sub-aperture stitching technology, stimulated emission depletion (STED) microscopy and protein nanopores are present, which achieve the multifunction of SICM. Thirdly, state-of-the-art ways that can improve imaging rate are demonstrated. Finally, a brief future outlook for SICM is discussed. [ABSTRACT FROM AUTHOR]

Simple impregnation technique was used to modify the surface of tungsten (VI) oxide (WO3) with Cu(II) nanoclusters at molar fraction 1, 3, and 5% mol. Cu(ІІ)–WO3 photo catalysts were studied by, UV-visible light spectra, and FTIR measurements were carried out, respectively. UV–vis reflectance method of Cu(ІІ)–WO3 nanoparticles display that the optical absorption was in the visible region of approximately 2.7 eV; this also assure the combination of Cu ions in the lattice of WO3 crystal. AFM images showed homogeneous distribution of copper in the matrix of WO3. Two bacterial pathogens, gram-positive Staphylococcus aureus and gram-negative Escherichia coli, were lighted for 180 and 240 min with Cu(ІІ)–WO3 nanoparticles for photocatalytic inactivation. This displays a fundamental diminution in number of bacteria. The survival number of all bacteria species is not influenced in dark with nanoparticles and in light condition without nanoparticles. [ABSTRACT FROM AUTHOR]

Synthesis of silver nanoparticles (AgNPs) with desired physicochemical properties using a cost-effective, energy, and time efficient way is vital. In this study, we have optimized the synthesis of AgNPs through protein containing cell-free supernatant of Enterobacter cloacae (SMP1). 23 full factorial central composite design (CCD) of the response surface methodology (RSM) was used for the process optimization. Individual and mutual interaction effects of the experimental variables including temperature, pH, inoculum size, and metal concentration were investigated on the synthesis of AgNPs. Results showed the involvement of 15 kDa protein in the synthesis of AgNPs. The optimized values of pH, temperature, cell-free culture supernatant (CFCS), and metal concentration were 10, 37 °C, 10% (v/v) and 2 mM, respectively. Characterization of AgNPs using UV-Vis spectroscopy reveals surface plasmon resonance peak at 450 nm. AFM and TEM micrographs revealed oval and spherical shaped AgNPs with the size of spherical (15–44 nm) and oval (20–46 nm wide and 240–325 nm long) and zeta potential of −41.3 mV under different experimental conditions. The EDS, X-ray elemental mapping, and FTIR reviled the presence of metallic AgNPs and signatures for nitrogen, carbon, oxygen, sulfur, and functional groups of different biomolecules. [ABSTRACT FROM AUTHOR]

Molecular simulation was used to investigate the coadsorption mechanism of Na+ and H2O on the hydroxylated silicon wafer. Water molecules can form a 3.5 Å-thickness bimolecular structure at the solid–liquid interface. Near the solid surface, the density of water can reach approximately 1300 kg/m3. Na+ does not bond with SiOH directly but adsorbs near SiOH in the form of hydrated ions. The adsorption of Na+ on the surface belongs to the ion hydration outer ring adsorption. The adsorption sites of Na+ are mainly located in the first water molecular layer. In the system, the peak value of the bond length distribution curve of water molecules is 0.98 Å, while the peak value of the bond angle distribution curve is 102°. Due to the polarisation of Na+, the peak value of the bond angle distribution curve of the water molecules decreases, especially at the interface water. Additionally, Na+ can destroy the hydrogen bonds in the system. AFM imaging confirmed that NaCl is adsorbed on the surface in the form of granular aggregates and the adsorption of Na+ by SiOH is weak in aqueous solution. [ABSTRACT FROM AUTHOR]

Nanomechanical properties of polymer samples were calculated using an adhesive contact model appropriate for AFM indentation problems. A series of Polydimethylsiloxane (PDMS) samples were indented by the sharp indenter in the air by using an AFM, and dozens of the force–displacement curves of each sample were obtained. An adhesive contact model suitable for sharp indentation with adhesion was established based on the same assumptions of the JKR model which is only suitable for spherical indentation at small penetration depth. Differences between sharp indentation problems with and without adhesion were discussed, and the limitations of the traditional adhesion model were given. The elastic modulus was obtained by fitting experimental force–displacement curves with theoretical ones, and results were compared to those macroscopic values in literature. The adhesion energy between the indenter and the sample surface was accurately calculated using the adhesion model based on the calculated elastic modulus. The influence of the indenter tip angle on the calculation results of the elastic modulus was also discussed theoretically. In this study, the mechanical properties of polymer samples were calculated at the nanoscale considering the adhesion effect. [ABSTRACT FROM AUTHOR]