Search

This study deals with the effect of Cu on hydroxyapatite (HAp) thin films on silicon substrates prepared by pulsed laser deposition (PLD) technique for Cu concentrations ranging from 0 to 0.8 wt.%. Fourier transform infrared spectroscopy and Raman spectroscopy provide additional evidence of HAp in the films, which exhibit characteristic HAp bands such as the 960 cm−1 phosphate ion band. The X‐ray diffraction patterns confirm the presence of HAp, without copper‐related peaks, suggesting that it is not incorporated into the HAp lattice, which is present as an amorphous phase. X‐ray photoelectron spectroscopy confirms the presence of Cu on the HAp thin films, possibly related to the adsorption of Cu2+ on HAp surfaces through electrostatic or interactions with (PO4)3− groups. Atomic force microscopy shows that the roughness of the films varies depending on the presence or absence of copper ions. Finally, density functional theory and kinetic Monte Carlo simulations explain the effects of atomic diffusion on roughness and HAp clustering. These changes correlate with the contact angle values, indicating the formation of hydrophobic films due to copper inclusions. [ABSTRACT FROM AUTHOR]

Jordan's energy sector faces significant challenges due to rising fuel prices, making the exploration of local energy resources crucial. The abundant oil shale deposits in Wadi Thamad present a promising opportunity. Since Wadi Thamad oil shale has never been studied before, this research focuses on the Wadi Thamad basin near Madaba, Jordan, aiming to comprehensively characterize its oil shale using advanced analytical techniques. Using X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray fluorescence, scanning electron microscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry, this study assesses the mineralogical, chemical, and thermal properties of Wadi Thamad oil shale. The findings reveal calcite and quartz as the primary minerals, with significant aliphatic, CO2, hydroxyl, and carboxyl groups. Elemental analysis highlights essential oxides, such as CaO and SiO2. Fischer assay results indicate an oil content of 5.3–10.1 wt%, a gross‐calorific value of 4.56–7.69 MJ/kg, and a sulfur content of 1.77–2.10 wt%. The peak pyrolysis temperature is 432.4°C from TGA. This research's novelty lies in its comprehensive approach to characterizing the underexplored Wadi Thamad oil shale basin. The findings enhance the understanding of Wadi Thamad's geological composition and underscore its potential as a local energy resource, contributing valuable data to Jordan's energy portfolio and offering economic benefits. [ABSTRACT FROM AUTHOR]

The topography analysis of engineered rough surfaces provides an insight for an analysis of thin film lubrication regime. The systematic characterization of rough surface helps to improve the lifetime performance and the reliability of high-power density (power throughput/weight) machines. Tribological phenomena like rolling contact fatigue, fretting fatigue, and wear significantly depend on characteristics of rough surfaces. This work demonstrates the numerical synthesis and characterization of various rough surfaces. Surface topographies are numerically simulated using nonlinear conjugate gradient method (NCGM) along with the Johnson translator system method. The influence of pattern ratio (γ), skewness (Ssk) and kurtosis (Sku) on topography parameters (summit density, summit radius of curvature) are discussed in detail. It is concluded that a selection of surface topography significantly alters topography parameters which ultimately may affect surface dominant phenomena. The trend on topography parameters obtained from numerical findings are also compared with the surface measurements study for the completeness of the work. [ABSTRACT FROM AUTHOR]

Mesoscopic carbon‐based perovskite solar cells (C‐PSCs) have the potential to be manufactured at an industrial scale by utilizing screen‐printing, a simple, affordable, and commercially mature process. As such, many recent publications have focused on enhancing performance through modifying cell architecture and perovskite chemistries. This work examines how ink rheology can be tuned to optimize cell performance through reducing the occurrence of common print defects to create higher quality m‐TiO2 films. Inks with different solvent dilutions and rheological profiles are assessed using high‐speed imaging through the screen‐printing visualization (SPV) technique, to investigate the impact of the viscosity and elasticity on ink separation mechanisms. The resultant film quality and its influence on device performances are then assessed. Ink separation lengths are minimized, and the formation of filaments ceases during printing, leading to improved TiO2 film topography and homogenous infiltration of the perovskite precursor. Consequently, PCE is improved by over 10% of the original efficiency in cells and 224 cm2 active area modules due to enhanced Voc and FF. These results not only provide key insights into tailoring ink rheology, to achieve improved print homogeneity and higher performing cells, but also aid further work on enhancing the performance of other screen‐printed functional films. [ABSTRACT FROM AUTHOR]

Featured Application: Photoluminescence and resonant Raman scattering have the potential to characterize surface roughness. These optical spectroscopies can be complementary tools for monitoring and controlling semiconductor manufacturing processes. Surface roughness significantly affects light reflection and absorption, which is crucial for light–matter interaction studies and material characterization. This work examines how nanoscale surface roughness affects the electronic states and vibrational properties of cadmium telluride (CdTe) single crystals, using photoluminescence (PL) and resonant Raman scattering (RRS) spectroscopies. We have evaluated the surface roughness across various sample regions as the root-mean-square (RMS) value measured by atomic force microscopy (AFM). At room temperature, increasing RMS correlated with changes in PL intensity and peak width, as well as enhanced second-order longitudinal optical (2LO) phonon mode intensity. Fitting the PL and RRS spectra with Gaussian and Lorentzian functions, respectively, allowed us to explain the relationship between surface morphology and the observed spectral changes. Our findings demonstrate that surface roughness is a critical parameter influencing the surface states and vibrational properties of CdTe, with implications for the performance of CdTe-based devices. [ABSTRACT FROM AUTHOR]

Abstract Jordan's energy sector faces significant challenges due to rising fuel prices, making the exploration of local energy resources crucial. The abundant oil shale deposits in Wadi Thamad present a promising opportunity. Since Wadi Thamad oil shale has never been studied before, this research focuses on the Wadi Thamad basin near Madaba, Jordan, aiming to comprehensively characterize its oil shale using advanced analytical techniques. Using X‐ray diffraction, Fourier transform infrared spectroscopy, X‐ray fluorescence, scanning electron microscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry, this study assesses the mineralogical, chemical, and thermal properties of Wadi Thamad oil shale. The findings reveal calcite and quartz as the primary minerals, with significant aliphatic, CO2, hydroxyl, and carboxyl groups. Elemental analysis highlights essential oxides, such as CaO and SiO2. Fischer assay results indicate an oil content of 5.3–10.1 wt%, a gross‐calorific value of 4.56–7.69 MJ/kg, and a sulfur content of 1.77–2.10 wt%. The peak pyrolysis temperature is 432.4°C from TGA. This research's novelty lies in its comprehensive approach to characterizing the underexplored Wadi Thamad oil shale basin. The findings enhance the understanding of Wadi Thamad's geological composition and underscore its potential as a local energy resource, contributing valuable data to Jordan's energy portfolio and offering economic benefits.

A reliable `in situ' method for wavefront sensing in the soft X-ray domain is reported, developed for the characterization of rotationally symmetric optical elements, like an ellipsoidal mirror shell. In a laboratory setup, the mirror sample is irradiated by an electron-excited (4.4 keV), micrometre-sized (∼2 µm) fluorescence source (carbon Kα, 277 eV). Substantially, the three-dimensional intensity distribution I(r) is recorded by a CCD camera (2048 × 512 pixels of 13.5 µm) at two positions along the optical axis, symmetrically displaced by ±21–25% from the focus. The transport-of-intensity equation is interpreted in a geometrical sense from plane to plane and implemented as a ray tracing code, to retrieve the phase Φ(r) from the radial intensity gradient on a sub-pixel scale. For reasons of statistical reliability, five intra-/extra-focal CCD image pairs are evaluated and averaged to an annular two-dimensional map of the wavefront error {\cal W}. In units of the test wavelength (C Kα), an r.m.s. value \sigma_{\cal{W}} = ±10.9λ0 and a peak-to-valley amplitude of ±31.3λ0 are obtained. By means of the wavefront, the focus is first reconstructed with a result for its diameter of 38.4 µm, close to the direct experimental observation of 39.4 µm (FWHM). Secondly, figure and slope errors of the ellipsoid are characterized with an average of ±1.14 µm and ±8.8 arcsec (r.m.s.), respectively, the latter in reasonable agreement with the measured focal intensity distribution. The findings enable, amongst others, the precise alignment of axisymmetric X-ray mirrors or the design of a wavefront corrector for high-resolution X-ray science.

3-[5-(Cycloheximino)-4,5-dihydro-1,3,4-thiadiazol-2-yl]pyridine-2-amine was synthesized and used to make a novel pyrazole derivative embedded polymer inclusion membrane (Py@PIM). The surface and structure morphology of Py@PIM was detected using thermogravimetric analysis, FT-IR spectroscopy and scanning electron microscopy. Donnan dialysis system was also used to assess the transport efficacy of Py@PIM towards 5 heavy metals (Co, Cd, Cu, Ni, Pb). The results show that according to the kinetic coefficient, the order is Pb > Ni > Co > Cd > Cu. Similar kinetic order was also observed in multiple cation experiments, in experiments where all cations were mixed in a single cell. [ABSTRACT FROM AUTHOR]

Many functional properties of spray-dried microparticles are affected by the presence and composition of the materials used in the matrix and on the surface. The characteristics of these materials are an essential factor because any damage or alteration on the microparticle surface can affect the protection and retention of the bioactive-loaded delivery system and influence its interaction with the environment. There is a real gap between scientific concerns from the field and accessible reviews on the subject. This review presents a detailed description of the surface modification of spray-dried powders for improving the powder quality, efficiency of the microencapsulation, and microencapsulation process design in food industries. Additionally, the theoretical foundation, mechanisms, and methods used to understand the surface modification of spray-dried food powders are highlighted. Therefore, for a better understanding of the mechanisms involved in the particle surface formation, the application of advanced microscopy techniques and x-ray photoelectron spectroscopy (XPS) used together have offered very precise and detailed results under different conditions at the molecular level. These findings will contribute to further research improvement about the surface composition of spray-dried microparticles and how they influence on their functional properties. [ABSTRACT FROM AUTHOR]

Zirconia implants have emerged as a valuable alternative for clinical scenarios where aesthetic demands are high, as well as in cases of hypersensitivity to titanium or for patients who refuse metallic objects in their bodies due to personal reasons. However, these implants have undergone various changes in geometry, manufacturing techniques, and surface modifications since the introduction of the first zirconia implants. The present study aims to review the current evidence on zirconia implants, considering the changes they have undergone in recent years. Additionally, it aims to analyze the three-dimensional surface characteristics of a failed zirconia implant using scanning electron microscopy and elemental analysis with energy-dispersive X-ray spectrometry (EDX). A zirconia implant lost three weeks after placement was immediately assessed using VP-SEM equipment and chemically analyzed by EDX using a 410-M detector connected to the microscope. Sparse material depositions were found on all parts of the implant, with a notable concentration in the thread grooves. The elements identified in the sample included zirconium, oxygen, carbon, calcium, and phosphorus. This report demonstrates that the surface of zirconia implants can accumulate elements early in the process of bone matrix neoformation, which is consistent with the initial stage of osseointegration. [ABSTRACT FROM AUTHOR]

A reliable 'in situ' method for wavefront sensing in the soft X‐ray domain is reported, developed for the characterization of rotationally symmetric optical elements, like an ellipsoidal mirror shell. In a laboratory setup, the mirror sample is irradiated by an electron‐excited (4.4 keV), micrometre‐sized (∼2 µm) fluorescence source (carbon Kα, 277 eV). Substantially, the three‐dimensional intensity distribution I(r) is recorded by a CCD camera (2048 × 512 pixels of 13.5 µm) at two positions along the optical axis, symmetrically displaced by ±21–25% from the focus. The transport‐of‐intensity equation is interpreted in a geometrical sense from plane to plane and implemented as a ray tracing code, to retrieve the phase Φ(r) from the radial intensity gradient on a sub‐pixel scale. For reasons of statistical reliability, five intra‐/extra‐focal CCD image pairs are evaluated and averaged to an annular two‐dimensional map of the wavefront error. In units of the test wavelength (C Kα), an r.m.s. value = ±10.9λ0 and a peak‐to‐valley amplitude of ±31.3λ0 are obtained. By means of the wavefront, the focus is first reconstructed with a result for its diameter of 38.4 µm, close to the direct experimental observation of 39.4 µm (FWHM). Secondly, figure and slope errors of the ellipsoid are characterized with an average of ±1.14 µm and ±8.8 arcsec (r.m.s.), respectively, the latter in reasonable agreement with the measured focal intensity distribution. The findings enable, amongst others, the precise alignment of axisymmetric X‐ray mirrors or the design of a wavefront corrector for high‐resolution X‐ray science. [ABSTRACT FROM AUTHOR]

Laser powder bed fusion (LPBF) is an additive manufacturing technique that enables significant design freedom and high-complexity part production. However, the process requires unconventional analysis methods for surface characterization due to process-induced variations. One possible technique is to use in-situ optical tomography (OT) technique for quality control of LPBF surfaces during fabrication. In-situ characterization approach would enable better first time yield and inspection possibility of inner channels without the need of destructive testing. In this study, samples with varied angles and process parameters are produced by LPBF. Camera images are collected during the production per every process layer using the optical-tomography system. These OT images are interpreted to obtain roughness estimates of sample overhanging surfaces. OT roughness outputs are analyzed and correlated with optical coherence scanning interferometry (CSI) measurements. The relationship between OT surface roughness estimates and optical measurements for different process parameters are presented. The possibility of using an in-situ surface analysis method for the characterization of LPBF surfaces is discussed. [ABSTRACT FROM AUTHOR]

Germanium and other brittle single crystal materials can be diamond turned with negative rake angle tools, but to maintain surface integrity parameters are typically chosen conservatively. This work describes experiments performed on (100)Ge crystal samples that support a recent scientific finding: increasing the surface speed in diamond turning of germanium improves surface integrity. Materials are machined on a modern ultraprecision diamond turning machine at constant surface speed and constant feed per revolution keeping both the geometric character and the material flow dynamics constant during machining. Forces are measured in the experiments at cutting speeds ranging from 0.2 m/s to 10 m/s. Surface roughness of the machined surfaces was characterized using coherence scanning interferometry and surface analysis. The key findings of the work are (a) force and specific forces decrease by approximately a factor of 2 over the cutting speed range and (b) surface damage substantively decreases with cutting speed. This is correlated to the behavior of the cutting forces during machining and the chip geometry. The findings indicate that higher material removal rates can be obtained in diamond turning of germanium and that this increase in material remove rates also improves surface integrity. [ABSTRACT FROM AUTHOR]

The interlaminar strength of mechanically interlocked polymer-metal hybrids is strongly determined by the surface geometry at the interface. To improve the interlaminar strength, laser beam machining is among the most applied technologies for manufacturing a predefined and complex surface structure. Previously, the fractal dimension of interfaces in polymer-metal-hybrids has been introduced as scale-independent measure. It has been correlated quantitatively with the interlaminar strength using values derived from cross-sectional images. Therefore, the quality of the prediction directly depends on the accuracy of the measured surface data. However, a holistic acquisition of surface structure for the determination of the fractal dimension including 3D methods has not been investigated so far. In this study, laser machining was used to generate five different pin-structures on samples of the aluminum alloy EN AW-6082. Surface characterization was realized by light microscopy (2D), laser scanning microscopy (3D) and X-ray microscopy (3D). Subsequently, the fractal dimension was determined using a box-counting algorithm as well as slit-island method. The results show that all methods regarded are appropriate to determine the fractal dimension, but differ in the specific results. The functional characteristics of each method are described in detail and potentials for applications are outlined. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate how the amount of ZnCl2 and temperature affect the process of converting waste wheat bran, known for its hemicellulose struc-ture, into porous material. The characterization of the wheat bran was done using proximate and primary component analysis, and Thermogravimetric analysis (TG) test, Fourier Transform Infrared Spectroscopy (FT-IR) spectra, Energy-dispersive X-ray spectroscopy (EDS) results, and Scanning electron microscopy (SEM) images. The influence of temperature on the surface areas of activated carbons is more significant than the impact of varying the amount of ZnCl2. When the carbonization temperature reached 500 °C, porous structures developed, and the highest surface areas achieved for all impregnation ratios (1:1, 2:1, and 3:1) were 1234, 1478, and 1422 m²/g, respectively. Activated carbon was found to have acidic (0.88 mmol/g) and basic (0.54 mmol/g) functional groups on its surface, after being synthesized through carbonization at 500 °C using ZnCl2 at a 2:1 impregnation ratio in accordance with Boehm titration. This promising activared carbon made from wheat bran, activated by ZnCl2, is efficient and environmentally friendly, and it is a potential solution for water pollution treatment. [ABSTRACT FROM AUTHOR]

In this study, two different water‐soluble Schiff base ligands as sodium(Z)‐3((2,5‐dihydroxybenzylidene)amino)benzene sulfonate (SLI) ve sodium (Z)3‐((3,4‐dihydroxybenzylidene)amino)benzene sulfonate (SLII) were synthesized as a result of the condensation reaction of 3‐aminobenzenesulfonicacid containing sulfo group with 2,5‐dihydroxybenzaldehyde and 3,4‐dihydroxybenzaldehyde, respectively. The chemical structures of the synthesized Schiff base ligands were characterized by melting point determination, elemental analysis, FT‐IR and 1H‐NMR techniques. Electrochemical behaviors of synthesized SLI and SLII ligands were examined by cyclic voltammetry technique against Ag/AgCl/KCl(sat) at the glassy carbon electrode in Britton Robinson buffer solution, pH 5.0. Electrode surfaces modified with SLI and SLII ligands were characterized by cyclic voltammetry technique in the presence of ferrocene and potassium hexacyanoferrate (III) redox probes, water contact angle measurement, scanning electron microscope and atomic force microscope and compared with the data of the bare glassy carbon electrode surface. Theoretical calculations of SLI and SLII ligand were performed with Density Functional Theory (DFT) and compared with experimental results. [ABSTRACT FROM AUTHOR]

The risk of enamel deterioration that frequently coexists with debonding of orthodontic teeth brackets elevates the mandate for finding an optimum approach for debonding them without harmful effects. This in-vitro study is intended to compare the effects of two different laser modes (scanning and circular) and a conventional method on the enamel surface after debonding orthodontic brackets. 66 extracted premolars were assigned into 3 groups. After that, light-cure composite resin was used to attach the ceramic brackets to the teeth. Amongst the test groups, Group I: specimens that were debonded using conventional debonding using pliers; Group 2: specimens that were debonded using Er, Cr: YSGG laser applications using the circular motion method; and Group 3: specimens that were debonded using Er, Cr: YSGG laser applications using the scanning motion method. Adhesive Remnant Index (ARI) assessment, intra-pulpal temperature increase, enamel surface roughness after polishing, and assessment of the microstructure of enamel were carried out with scanning electron microscopy. The gathered information was examined statistically. The conventional debonding method had a significantly higher proportion of adhesive remnant index (ARI) scores of 2 and 3 in comparison to the circular (p <.004) and scanning laser groups (p <.001). There was no significant difference in ARI scores between the circular and scanning laser groups (p >.05). Moreover, the circular and scanning laser debonding methods resulted in a significantly higher proportion of Enamel Surface Roughness (ESR) scores of 0 and a lower proportion of ESR scores of 3 compared to the conventional technique group (p <.001). However, there was no significant difference in ESR scores between the circular and scanning laser methods (p =.945). Lastly, the average intra-pulpal temperature was significantly higher in the circular laser group (1.9 ± 0.5) compared to the scanning laser group (0.9 ± 0.2) with p <.001. Er, Cr: YSGG laser irradiation is a tool that shows promise for debonding ceramic brackets with minimal harm to the enamel surface. The scanning laser technique is more desirable due to the lower intra-pulpal temperature increase. [ABSTRACT FROM AUTHOR]

Abstract The purpose of this research was to examine the viability of applying a flawless polyaniline coating on steel spearheads to preserve them and protect them from corrosion. The spearpoints, thought to be archaeologically significant, were acquired from the Military Museum in Al-Qala, Egypt. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy were used to characterize the spearheads chemical composition and microstructure (EDX). The spearheads were determined to be constructed of steel and to have a coating of ferric oxide and other corrosion products on their exteriors. After that, a flawless polyaniline coating was electrochemically deposited onto the spearpoints in a way that was both quick and cheap. Many types of corrosion tests, such as electrochemical impedance spectroscopy and potentiodynamic polarization (PDP) readings, were used to determine the coating’s effectiveness. The steel spearheads’ findings revealed a significant improvement in their resistance to corrosion after being coated with flawless polyaniline. The coating served as a barrier, blocking out water and other corrosive substances and slowing the buildup of corrosion byproducts on the spearpoints. In conclusion, our research shows that a flawless polyaniline coating may be an effective anti-corrosion treatment for ancient steel artifacts. The approach is straightforward, cheap, and readily scalable for massive conservation efforts.

One of the alternative materials used for conducting conservation treatment of iron artifacts is the rust converter, since it generates barrier properties and more stable oxides. The protective properties and surface modifications from using Mimosa tenuiflora extract as a green rust converter on a gray iron oxide layer were studied. The surface characterization was carried out using a Scanning Electron Microscope coupled to an energy-dispersive X-ray spectrometer (SEM-EDS), along with infrared spectroscopy (IR), Raman spectroscopy, X-ray Diffraction (XRD), and Water Contact Angle (WCA). Electrochemical characterization was performed with an Electrochemical Impedance Spectroscope (EIS) using 3.5 wt.% NaCl as the electrolyte. According to the results of the Raman spectroscopy and XRD, the layer of corrosion products formed after 90 days in the atmosphere was composed of goethite, lepidocrocite, maghemite, hematite, and magnetite. The surface of the corrosion products was transformed with the rust converter into an amorphous and microcracked layer. By IR, the Fe-O and C-O-Fe bonds associated with the iron chelate were found with absorption bands at 1540 and 1567 cm−1, respectively. By XRD, a modification of the magnetite crystallinity was observed. Finally, the Water Contact Angle and the protective capacity of the corrosion products were improved by the presence of the rust converter.

The aim of this work is to investigate the variations in microstructure, hardness, wear and surface roughness between as-cast and heat treated trace elements added A356 alloy. Alloy A was prepared by adding 1 wt.% magnesium to A356 alloy which was used as the base material for the preparation of alloys with zinc (Zn) and copper (Cu) particles as alloying elements. Other set of samples was fabricated where Cu-coated Zn and Cu were added as reinforcements to base matrix A. The microstructural analysis indicated that the addition of Zn to A356 as an alloying element had a limited effect on controlling the grain size during solidification compared to Cu. The addition of Cu as reinforcement resulted in a higher proportion of pro eutectic α-Al phase, leading to finer grain boundaries. Micro-polishing test was conducted on the alloys and composites by determining the surface roughness (Ra) value using profilometer to study the changes in surface roughness under individual load conditions of 20 and 40 N. In the as-cast condition, the addition of Cu increased the hardness by 39% and 58% over the base alloy, respectively. Age-hardening treatment significantly enhanced the wear resistance properties of unreinforced alloys and composites at both aging temperatures, especially at 100 °C. Composite samples exhibited excellent surface finish (lower surface roughness) compared to alloy samples, attributed to the presence of hard reinforcement particles.

This study addressed the preparation of nanocomposites consisting of polyvinyl alcohol (PVA) and titanium oxide (TiO2) for utilization in optoelectronics technologies. PVA/10%TiO2 nanocomposite samples with a mean thickness of 0.1mm were created using the solution casting method. The PVA/TiO2 films are irradiated with oxygen fluences of 0.4×1017, 0.8×1017 and 1.2×1017 ions/cm2. The X-ray diffraction (XRD) and FTIR methodologies were employed to investigate the impact of ion bombardment on the structural characteristics and functional groups of PVA/TiO2 substrates. Diffraction peaks are 20.1° for PVA and 25.4° for TiO2, indicating the successful PVA/TiO2 nanocomposite construction. The absorbance (A) of unirradiated and irradiated samples was measured using UV–Vis spectroscopy within a wavelength range of 200–1100nm. Band gaps (Eg) were calculated using Tauc’s formula for PVA/TiO2 films, exhibiting a decrease from 4.56eV for unirradiated PVA/TiO2 film to 4.16, 3.95 and 3.88eV at ion fluences of 0.4×1017, 0.8×1017 and 1.2×1017 ions/cm2, respectively. Furthermore, the Ubrach tail has a rise of 1.23eV for unirradiated PVA/TiO2 to 1.28eV, 1.4eV and 1.77eV for irradiated films with ion fluences of 0.4×1017, 0.8×1017 and 1.2×1017 ions/cm2, respectively. Additionally, following ion irradiation, the PVA/TiO2 absorption edge Ee, which was 3.56eV, decreased to 3.48, 3.37 and 3.23eV, with increasing ion beam fluences. This study demonstrated that the optical behaviors of the PVA/TiO2 films were altered under bombardment, suggesting their potential applicability in optical devices. [ABSTRACT FROM AUTHOR]

Several researchers have recently expressed interest in additively manufactured electrodes for machining and surface modification applications. The additively manufactured AlSi10Mg tool electrode is one of the promising candidate materials for non-conventional processes. This research investigates the process parameters of laser powder bed fusion (L-PBF) processed AlSi10Mg tool electrodes for the electro-spark deposition process (ESD). The selected deposition parameters, namely, peak current (Pc), pulse-on time (Pon) and deposition time (DT) with various levels and experimentation, are based on the box-behnken design (BBD) of the response surface methodology. The deposition was carried out to analyze the output responses of material deposition rate (MDR), additive tool wear rate (ATWR) and surface roughness (SR). The multi-objective optimization was performed to minimize the ATWR and SR and maximize the MDR. The optimized ESD parameters of Pc = 6 A, Pon = 20 μ s, and DT = 5 min were found with predicted responses of MDR = 0.019 mg/min, ATWR = 0.095 mg/min and SR = 3.86 μ m. The deposited surface witnessed the formation of debris, microcracks, and a solidified surface with a dark region and accumulated worn debris that has an elongated and flat shape. The workpiece substrate was exposed to a significant amount of additive tool electrode material (Si, Al, O, Mg, S), and different intermetallic ( Al 2 6 Si) 0.148, Al2O3, and Al2S3 formations have been recognized. This finding corroborates the efficient usage of L-PBF AlSi10Mg electrodes for ESD processes. [ABSTRACT FROM AUTHOR]

Bio-polybutylene succinate (PBS) is a biodegradable polymer obtained from renewable feedstock having physical–mechanical properties like traditional low-density polyethylene (LDPE). PBS is employed by many manufacturing sectors, from biomedical to agri-food and cosmetics. Although some studies have already evaluated the resistance of PBS to photodegradation caused by natural outdoor solar exposure (UVA-UVB), a systematic study on the resistance to degradation caused by exposure to UVC rays, which is the subject of this study, has not yet been carried out. PBS was exposed to UVC either neat or filled with 2% carbon black (CB). Mechanical and physical characterization (tensile, hardness, calorimetry, contact angle, morphology, and surface roughness analyses) indicates that the bulk and surface properties of the polymer matrix changes after exposure to UVC radiations, due to a severe degradation. However, the presence of carbon black compensates for the degradation phenomenon. Because UVC rays are used for the sterilization process, necessary in applications such as biomedical, cosmetic, pharmaceutical, food, and other products, a comparison of the protocol used in this paper with the literature's data has been reported and discussed. [ABSTRACT FROM AUTHOR]

The goal of the study was to compare the surface characteristics of typical implant materials used in orthopedic surgery and traumatology, as these determine their successful biointegration. The morphological and chemical structure of Vortex plate anodized titanium from commercially pure (CP) Grade 2 Titanium (Ti2) is generally used in the following; non-cemented total hip replacement (THR) stem and cup Ti alloy (Ti6Al4V) with titanium plasma spray (TPS) coating; cemented THR stem Stainless steel (SS); total knee replacement (TKR) femoral component CoCrMo alloy (CoCr); cemented acetabular component from highly cross-linked ultrahigh molecular weight polyethylene (HXL); and cementless acetabular liner from ultrahigh molecular weight polyethylene (UHMWPE) (Sanatmetal, Ltd., Eger, Hungary) discs, all of which were examined. Visualization and elemental analysis were carried out by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Surface roughness was determined by atomic force microscopy (AFM) and profilometry. TPS Ti presented the highest Ra value (25 ± 2 μm), followed by CoCr (535 ± 19 nm), Ti2 (227 ± 15 nm) and SS (170 ± 11 nm). The roughness measured in the HXL and UHMWPE surfaces was in the same range, 147 ± 13 nm and 144 ± 15 nm, respectively. EDS confirmed typical elements regarding the investigated prosthesis materials. XPS results supported the EDS results and revealed a high % of Ti4+ on Ti2 and TPS surfaces. The results indicate that the surfaces of prosthesis materials have significantly different features, and a detailed characterization is needed to successfully apply them in orthopedic surgery and traumatology. [ABSTRACT FROM AUTHOR]

Ti-3Al-2.5V superalloy is a highly structural and functional material predominantly used in hydraulic tubing for aircraft like Boeing and honeycomb structures in structural applications. In this study, the Wire Electrical Discharge Machining input parameters considered for observation were Pulse on time (Ton), Pulse off time (Toff), Wire Feed (WF), and Wire Tension (WT). The output responses analyzed were kerf width (KW) and Surface Roughness (SR). Taguchi's L16 orthogonal array was used for conducting experiments. The smallest and largest kerf width values observed were 0.311 and 0.344 mm, respectively. The lowest and highest surface roughness values observed were 1.530 and 2.649 µm, respectively. Signal-to-noise ratio response and Analysis of Variance revealed that Pulse on time (Ton) was the most influential parameter affecting kerf width and surface roughness. Microstructure analysis of machined samples and wire electrodes was carried out with a Scanning Electron Microscope. [ABSTRACT FROM AUTHOR]

As a corrosion barrier layer, open-air plasma-assisted organosilicon coating was applied on AZ91D Mg alloy. Organosilicon-coated AZ91D samples, prepared from two different plasma coating processes, were used for corrosion evaluation based on multistep electrochemical and H2 collection measurements in 3.5 wt% sodium chloride (NaCl) solution. Some coated AZ91D samples were characterized with and without corrosion exposure in NaCl solution using electron microscopies and X-ray chemical analysis techniques. The results indicate that the organosilicon coatings from open-air plasma processes are effective to delay the initiation of corrosion attack and also reduce the corrosion rate for AZ91D substrate. The corrosion attack was considered to develop after permeation of NaCl solution through the coating layer. [ABSTRACT FROM AUTHOR]

A cold cathode plasma source is constructed for modifying PTFE surface characteristics. The source was easily built, had a consistent plasma discharge medium and acceleration system. A cylindrical Langmuir probe is also used to evaluate plasma parameters like density, temperature or even plasma potential. This probe is designed to be moveable so that it may approach any desired position in the plasma volume. The influences of nitrogen pressure and probe-cathode gap on plasma parameters were investigated. The electron temperature T e fluctuated from 7. 7 3 × 1 0 4 to 6. 8 × 1 0 4 eV as the pressure rises from 0.2 to 0.4 mbar. Further, by increasing the cathode-probe gap from 0.4 to 2 cm, the electron densities increased from 0. 4 6 × 1 0 1 0 cm − 3 to 0. 8 9 × 1 0 1 0 cm − 3 . Furthermore, the contact angles, work of adhesion and surface free-energy of pristine as well as irradiated PTFE films, were estimated. The results demonstrated that by extending the plasma exposure duration from 0 to 12 min, the water contact angle is lowered from 82.2∘ to 30.5∘. At these conditions, the work of adhesion is raised from 81.9 to 134.1 mJ/m2, as the surface free energy is increased from 29.8 to 71.8 mJ/m2. [ABSTRACT FROM AUTHOR]

This research delineates the corrosion inhibitory efficiency of two newly synthesized benzoxazepine derivatives – [3,3‐dimethyl‐11‐phenyl‐3,4,5,11‐tetrahydrodibenzo[b,e] [1,4]oxazepine‐1(2 H)‐one (S1)] and [11‐(4‐chlorophenyl)‐3,3‐dimethyl‐3,4,5,11‐tetrahydrodibenzo[b,e][1,4]oxazepine‐1(2 H)‐one (S2)] – on mild steel in 1M HCl milieu. These derivatives were characterized by proton (1H NMR) and carbon (13C NMR) nuclear magnetic resonance spectroscopy. The experimental approach encompassed potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) techniques. The corrosion inhibition efficacy of S1 and S2 was concentration‐dependent, with their efficiencies peaking at 92.0 % and 92.1 %, respectively, at a 10−3 M concentration. Surface characterization, conducted using scanning electron microscopy (SEM), energy‐dispersive X‐ray analysis (EDS), X‐ray diffraction (XRD), contact angle measurements, and X‐ray photoelectron spectroscopy (XPS), corroborated the formation of a protective barrier layer on the mild steel surface. Additionally, using an inductive approach, UV‐visible spectrometry was employed to elucidate the adsorption behaviors of these inhibitors on the steel surface. Density functional theory (DFT) and molecular dynamics (MD) simulations were utilized to decipher the interaction mechanisms and adsorption modalities, unveiling critical insights into the interactions of S1 and S2 with the mild steel surface. This comprehensive analysis highlights the robust corrosion inhibition potential of the newly synthesized benzoxazepine derivatives and illuminates their prospective utility as effective inhibitors for mild steel in corrosive environments. [ABSTRACT FROM AUTHOR]

Polymers are essential in several sectors, yet some applications necessitate surface modification. One practical and eco-friendly option is non-thermal plasma exposure. The present research endeavors to examine the impacts of dielectric barrier discharge atmospheric pressure plasma on the chemical composition and wettability properties of acrylonitrile butadiene styrene surfaces subject to the action of additive manufacturing. The plasma source was produced by igniting either helium or argon and then adjusted to maximize the operational conditions for exposing polymers. The drop in contact angle and the improvement in wettability after plasma exposure can be due to the increased oxygen-containing groups onto the surface, together with a reduction in carbon content. The research findings indicated that plasma treatment significantly improved the wettability of the polymer surface, with an increase of up to 60% for both working gases, while the polar index increased from 0.01 up to 0.99 after plasma treatment. XPS measurements showed an increase of up to 10% in oxygen groups at the surface of He–plasma-treated samples and up to 13% after Ar–plasma treatment. Significant modifications were observed in the structure that led to a reduction of its roughness by 50% and also caused a leveling effect after plasma treatment. A slight decrease in the glass and melting temperature after plasma treatment was pointed out by differential scanning calorimetry and broadband dielectric spectroscopy. Up to a 15% crystallinity index was determined after plasma treatment, and the 3D printing process was measured through X-ray diffraction. The empirical findings encourage the implementation of atmospheric pressure plasma-based techniques for the environmentally sustainable manipulation of polymers for applications necessitating higher levels of adhesion and specific prerequisites. [ABSTRACT FROM AUTHOR]

Compact heat exchangers, commonly used in oil and gas offshore platforms, are thermal devices that promote high heat transfer rates due to a large ratio of the heat transfer surface area per volume. It is manufactured commonly through diffusion welding, a thermo-mechanical process that joins flat surfaces in contact by applying pressure and temperature, during a defined time. In this context, surface quality is a highly relevant topic since the machining process affects the surface and consequently the contact area for diffusion welding, having an impact on the quality of welding. Photochemical machining is the main process used to machine the channels in compact heat exchangers. As an alternative process to fabricate channeled plates, abrasive waterjet machining can be used, being a process where abrasive particles are accelerated through a waterjet at high speed, used to cut out parts and generate complex 2D profiles geometries with a potential to high productivity in comparison to the other process. These two-machining processes affect the surface quality of the piece, increasing the roughness, reducing the surface homogeneity with the formation of craters and other voids, which can be a source of defects and stresses and can also increase the accumulation of fouling and the tendency to corrosion in these places. To avoid these effects, it is necessary to employ postprocessing techniques to homogenize and improve the surface quality, like electropolishing that is a surface finishing process used to remove roughness through anodic dissolution and to promote a homogeneous oxide passive layer. The present work aims to compare quantitatively the surface topography of machined sheets using surface characterization techniques of electron microscopy and optical interferometry. The surface quality of the initial commercial stainless sheet was compared, as a reference, after abrasive waterjet and photochemical machining, as well as after the electropolishing of abrasive waterjet machining and photochemical machining. It was observed that abrasive waterjet machining presented burr at the channel's edge and had an approximately 35% increase in Sa parameter when compared with the initial condition. Photochemical machining, however, did not have burr at the machined region but presented a decrease in quality of more than 90% regarding the Sa parameter compared with the base material. The use of electropolishing removed the burrs from the abrasive waterjet machining and reduced surface roughness after the two machining methods, with more than 50% for Sa, Sq, and Pt, being a potential technique to be used to improve the surface integrity in both machining processes and guarantee an effective diffusion welding. [ABSTRACT FROM AUTHOR]

Titanium has broad application prospects in the field of hard bone tissue repair and replacement due to its low density, an elastic modulus similar to that of human bone, and better biocompatibility than stainless steel and cobalt-based alloys. However, titanium is a biologically inert material with low biological activity. After implantation, it only physically bonds with bone instead of chemically bonding, which causes complications such as implant loosening. In this study, a strontiumdoped titanium dioxide coating was prepared on a titanium surface with micro-arc oxidation. Based on a systematic study of the surface properties of the strontiumdoped titanium dioxide coating, the biocompatibility and bioactivity of the coating were evaluated with in vitro cell experiments. The results showed that the strontium-doped titanium dioxide coating was successfully prepared on the titanium surface and exhibited strong bonding with the substrate. The coating surface had a porous structure, and the strontium was dispersed on the surface and inside the coating. The strontium ions were released slowly, which improved the corrosion and wear resistance of the titanium. In vitro cell experiments showed that the coating had good cell compatibility; it promoted the adhesion, proliferation and differentiation of MC3T3-E1 cells and exhibited good biological activity. These results showed that preparation of a strontium-doped titanium dioxide coating by micro-arc oxidation is feasible. The coating had a good surface morphology, improved the biological activity of the titanium and has good potential for clinical application. [ABSTRACT FROM AUTHOR]

IPS e.max Press, a lithium disilicate‐based glass ceramic, is renowned in dental restorations for its mechanical strength and aesthetic appeal. This study delves into its behavior within oral environments, employing electrochemical and surface analysis techniques. By utilizing cyclic polarization curves and impedance spectroscopy, we evaluated its degradation resistance. Surface morphology, composition, and crystal stability were explored through scanning electron microscopy (SEM)/energy‐dispersive X‐ray spectroscopy (EDX) and X‐ray powder diffraction (XRD) analysis. The glass ceramic exhibited robust resistance to localized degradation across all tested electrolytes. The degradation potential (Ecorr) varied with time and pH, indicating electrolyte influence. SEM/EDX affirmed oxide layer formation, while XRD confirmed a stable structure. While showcasing favorable resistance in saliva, citric acid, and lactic acid, IPS e.max Press demonstrated susceptibility to acetic acid. This comprehensive analysis enhances our understanding, providing valuable insights for the development of durable dental materials through a combination of electrochemical analysis and surface characterization. [ABSTRACT FROM AUTHOR]

Polyetheretherketone (PEEK), a biomaterial with appropriate bone-like mechanical properties and excellent biocompatibility, is widely applied in cranio-maxillofacial and dental applications. However, the lack of antibacterial effect is an essential drawback of PEEK material and might lead to infection and osseointegration issues. This study aims to apply a natural antibacterial agent, totarol coating onto the 3D printed PEEK surface and find an optimized concentration with balanced cytocompatibility, osteogenesis, and antibacterial capability. In this study, a natural antibacterial agent, totarol, was applied as a coating to fused filament fabrication (FFF) 3D printed PEEK surfaces at a series of increasing concentrations (1 mg/ml, 5 mg/ml, 10 mg/ml, 15 mg/ml, and 20 mg/ml). The samples were then evaluated for cytocompatibility with L929 fibroblast and SAOS-2 osteoblast using live/dead staining and CCK-8 assay. The antibacterial capability was assessed by crystal violet staining, live/dead staining, and scanning electron microscopy (SEM) utilizing the oral primary colonizer S. gordonii and isolates of mixed oral bacteria in a stirring system simulating the oral environment. The appropriate safe working concentration for totarol coating is selected based on the results of the cytocompatibility and antibacterial test. Subsequently, the influence on osteogenic differentiation was evaluated by alkaline phosphatase (ALP) and alizarin red staining (ARS) analysis of pre-osteoblasts. Our results showed that the optimal concentration of totarol solution for promising antibacterial coating was approximately 10 mg/ml. Such surfaces could play an excellent antibacterial role by inducing a contact-killing effect with an inhibitory effect against biofilm development without affecting the healing of soft and hard tissues around FFF 3D printed PEEK implants or abutments. This study indicates that the totarol coated PEEK has an improved antibacterial effect with excellent biocompatibility providing great clinical potential as an orthopedic/dental implant/abutment material. [Display omitted] • A natural antibacterial coating of totarol was added on 3D-printed PEEK surfaces. • Different totarol concentrations led to varying biocompatibility and antibacterial effect. • A dynamic biofilm formation system was used to mimic the oral clinical environment. • The optimal coating concentration with balanced biocompatibility, osteogenesis and antibacterial efficacy was around 10 mg/ml. • Totarol coated PEEK shed light on a promising candidate for dental implants and abutments. [ABSTRACT FROM AUTHOR]

The purpose of this research was to examine the viability of applying a flawless polyaniline coating on steel spearheads to preserve them and protect them from corrosion. The spearpoints, thought to be archaeologically significant, were acquired from the Military Museum in Al-Qala, Egypt. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy were used to characterize the spearheads chemical composition and microstructure (EDX). The spearheads were determined to be constructed of steel and to have a coating of ferric oxide and other corrosion products on their exteriors. After that, a flawless polyaniline coating was electrochemically deposited onto the spearpoints in a way that was both quick and cheap. Many types of corrosion tests, such as electrochemical impedance spectroscopy and potentiodynamic polarization (PDP) readings, were used to determine the coating's effectiveness. The steel spearheads' findings revealed a significant improvement in their resistance to corrosion after being coated with flawless polyaniline. The coating served as a barrier, blocking out water and other corrosive substances and slowing the buildup of corrosion byproducts on the spearpoints. In conclusion, our research shows that a flawless polyaniline coating may be an effective anti-corrosion treatment for ancient steel artifacts. The approach is straightforward, cheap, and readily scalable for massive conservation efforts. [ABSTRACT FROM AUTHOR]

The present research paper explores the potential of electrospun nanofibers in the promising field of skin tissue engineering. Specifically, we propose an advanced preparation and characterization of an electrospun Polyurethane/Calcium Chloride (PU/CaCl2) nanocomposite scaffold, devised to boost the scaffold's physicochemical and biological properties for skin tissue regeneration. By incorporating CaCl2 into the PU matrix using an electrospinning process, we were able to fabricate a novel nanocomposite scaffold. The morphological examination through Field Emission Scanning Electron Microscope (FESEM) revealed that the fiber diameter of the PU/CaCl2 (563 ± 147 nm) scaffold was notably smaller compared to the control (784 ± 149 nm). The presence of CaCl2 in the PU matrix was corroborated by Fourier-Transform Infrared Spectroscopy (FTIR) and Thermogravimetric Analysis (TGA). Furthermore, the PU/CaCl2 scaffold exhibited superior tensile strength (10.81 MPa) over pristine PU (Tensile −6.16 MPa, Contact angle - 109° ± 1° and Roughness - 854 ± 32 nm) and revealed enhanced wettability (72° ± 2°) and reduced surface roughness (274 ± 104 nm), as verified by Contact angle and Atomic Force Microscopy. The developed scaffold demonstrated improved anticoagulant properties, indicating its potential for successful integration within a biological environment. The improved properties of the PU/CaCl2 nanocomposite scaffold present a significant advancement in electrospun polymer nanofibers, offering a potential breakthrough in skin tissue engineering. However, additional studies are required to thoroughly evaluate the scaffold's effectiveness in promoting cell adhesion, proliferation, and differentiation. We aim to catalyze significant advancements in the field by revealing the creation of a potent skin scaffold leveraging electrospun nanofibers. Encouraging deeper exploration into this innovative electrospun composite scaffold for skin tissue engineering, the PU/CaCl2 scaffold stands as a promising foundation for pioneering more innovative, efficient, and sustainable solutions in biomedical applications. [ABSTRACT FROM AUTHOR]

One of the alternative materials used for conducting conservation treatment of iron artifacts is the rust converter, since it generates barrier properties and more stable oxides. The protective properties and surface modifications from using Mimosa tenuiflora extract as a green rust converter on a gray iron oxide layer were studied. The surface characterization was carried out using a Scanning Electron Microscope coupled to an energy-dispersive X-ray spectrometer (SEM-EDS), along with infrared spectroscopy (IR), Raman spectroscopy, X-ray Diffraction (XRD), and Water Contact Angle (WCA). Electrochemical characterization was performed with an Electrochemical Impedance Spectroscope (EIS) using 3.5 wt.% NaCl as the electrolyte. According to the results of the Raman spectroscopy and XRD, the layer of corrosion products formed after 90 days in the atmosphere was composed of goethite, lepidocrocite, maghemite, hematite, and magnetite. The surface of the corrosion products was transformed with the rust converter into an amorphous and microcracked layer. By IR, the Fe-O and C-O-Fe bonds associated with the iron chelate were found with absorption bands at 1540 and 1567 cm−1, respectively. By XRD, a modification of the magnetite crystallinity was observed. Finally, the Water Contact Angle and the protective capacity of the corrosion products were improved by the presence of the rust converter. [ABSTRACT FROM AUTHOR]

Sustainable machining practices including dry cutting, cryogenic cooling (Cryo), and minimum quantity lubrication (MQL) techniques play an essential role in minimizing the extensive utilization of mineral-based cutting fluids, which can harm our ecology and health. However, the insufficient cooling and lubrication competencies of these eco-friendly strategies have some limitations that restrict their implementation in large-scale industrial applications. High-temperature generation in dry environment is associated with rapid tool wear and deteriorated surface quality. MQL at a high cutting speed usually requires better cooling capability; nevertheless, the inefficient lubrication mechanism offered by cryogenic environment affects the metal cutting performance and increases the machining cost. In this regard, hybrid lubrication technique was introduced to utilize the combined benefits of Cryo and MQL strategies for curtailing the thermal–mechanical damage associated with the tool and workpiece material. This paper reviews literature on sustainable hybrid lubrication techniques under three main topics, i.e., (a) Cyo-MQL lubrication fundamentals, (b) active heat transfer mechanisms, and (c) machinability performance in different machining processes, which includes tool life, cutting force, surface roughness, and microstructure characterization. Three data basis Google Scholar, Scopus, and Web of Sciences have been used to select relevant research articles on hybrid lubrication techniques. It is summarized that utilization of hybrid lubrication technique in different machining processes cannot only create a sustainable workpiece environment but can also remarkably improve the surface quality and material characteristics along with extending tool life and reducing cutting force. [ABSTRACT FROM AUTHOR]

In recent times, biochar has emerged as a promising and sustainable solution for COD reduction in wastewater treatment. This study explores the potential of chemically modified biochars as efficient adsorbents for the removal of organic contaminants, specifically oils, fats, and grease (OFG), from wool scouring wastewater. Proximate analysis revealed distinct properties among the biochars, with KOH-treated biochar demonstrating the most promising characteristics, including lower volatile matter, higher fixed carbon content, and reduced ash content, indicating a stable and carbon-rich structure. A meticulous examination of the KOH-treated biochar's surface characteristics revealed the presence of elevated carbon and nitrogen content, complemented by an expansive surface area measuring 724.4 m2/g. This surface area was at least twice as extensive as that observed in the other post-treated biochar samples. The kinetic adsorption of COD and soluble COD was well fitted by the pseudo-first-order model, with equilibrium achieved in approximately 200 min. The KOH-treated biochar exhibited the highest equilibrium adsorption capacities for both COD and soluble COD in both Dorset wool (Dorset) and Bluefaced Leicester (BFL) wastewater, highlighting its efficacy in OFG removal. Despite these promising results, further research is needed to explore biochar's surface characteristics, pore structure, and performance under diverse conditions, as well as its integration with existing treatment processes and potential for regeneration and reuse. This study contributes to advancing sustainable wastewater treatment methods using chemically modified biochars. [ABSTRACT FROM AUTHOR]

Fused deposition modeling (FDM) is widely employed in prototyping due to its cost-effectiveness, speed, and ability to produce detailed and functional prototypes using a variety of materials. Simultaneously, consideration for the use of biodegradable polymers and a general reduction in their usage while enhancing the production of polymer-based products is at the forefront of sustainable practices and environmental consciousness. This study investigates the impact fracture resistance of FDM models fabricated from Polylactic Acid (PLA), examining the influence of infill density (50% and 100% infill) and sample thickness (2 mm, 3 mm, and 5 mm). Optical microscopy, FTIR spectroscopy, and SEM analysis of PLA filament and fractured FDM PLA surfaces in impacted samples were conducted to ascertain the influence of process parameters on impact damage and failure mechanisms. The results indicate that a 100% infill profile with a 2 mm thickness should be avoided due to unpredictable behavior under impact. Conversely, a 5 mm thickness demonstrates significantly higher durability in comparison to a 50% infill profile. Optimal impact strength is observed in samples with a 3 mm thickness, suggesting potential material savings with 50% infill without compromising mechanical properties. The findings contribute valuable insights for refining FDM parameters and advancing the understanding of material behaviors in sustainable manufacturing practices. [ABSTRACT FROM AUTHOR]

Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density, environmental sustainability, and cost-effectiveness. However, the fast hydrogen evolution reaction (HER) in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity, low energy density, and low utilization. Thus, the conventionally used NaCl solute was proposed to be replaced by NaNO3 and acetic acid additive as a corrosion inhibitor, therefore an electrolyte engineering for long-life time Mg-air batteries is reported. The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching ∼1.8 V for initial 5 h at a current density of 0.5 mA/cm2 and significantly prolonged cells’ operational lifetime to over 360 h, in contrast to only ∼17 h observed in NaCl electrolyte. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition. The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

The problem of heavy metal pollution in water bodies poses a significant threat to both the environment and human health, as these toxic substances can persist in aquatic ecosystems and accumulate in the food chain. This study investigates the promising potential of using Microcystis aeruginosa extracellular polymeric substances (EPS) as an environmentally friendly, highly efficient solution for capturing copper (Cu2+) and nickel (Ni2+) ions in water treatment, emphasizing their exceptional ability to promote green technology in heavy metal sequestration. We quantified saccharides, proteins, and amino acids in M. aeruginosa biomass and isolated EPS, highlighting their metal-chelating capabilities. Saccharide content was 36.5 mg g−1 in biomass and 21.4 mg g−1 in EPS, emphasizing their metal-binding ability. Proteins and amino acids were also prevalent, particularly in EPS. Scanning electron microscopy (SEM) revealed intricate 3D EPS structures, with pronounced porosity and branching configurations enhancing metal sorption. Elemental composition via energy dispersive X-ray analysis (EDAX) identified essential elements in both biomass and EPS. Fourier transform infrared (FTIR) spectroscopy unveiled molecular changes after metal treatment, indicating various binding mechanisms, including oxygen atom coordination, π-electron interactions, and electrostatic forces. Kinetic studies showed EPS expedited and enhanced Cu2+ and Ni2+ sorption compared to biomass. Thermodynamic analysis confirmed exothermic, spontaneous sorption. Equilibrium biosorption studies displayed strong binding and competitive interactions in binary metal systems. Importantly, EPS exhibited impressive maximum sorption capacities of 44.81 mg g−1 for Ni2+ and 37.06 mg g−1 for Cu2+. These findings underscore the potential of Microcystis EPS as a highly efficient sorbent for heavy metal removal in water treatment, with significant implications for environmental remediation and sustainable water purification. [ABSTRACT FROM AUTHOR]

In this study, a carbon ceramic electrode (CCE) with improved electroanalytical performance was developed by bulk-modifying it with bismuth(III) oxide nanoparticles (Bi-CCE). Characterization of the Bi-CCE was conducted employing atomic force microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy. Comparative analysis was conducted using an unmodified CCE. The findings proved that the incorporation of Bi2O3 nanoparticles into the CCE significantly altered the morphology and topography of the ceramic composite, and it improved the electrochemical properties of CCE. Notably, the Bi-CCE demonstrated a prolonged operational lifespan of at least three months, and there was a high reproducibility of the electrode preparation procedure. The developed Bi-CCE was effectively employed to explore the electrochemical behavior and quantify the priority environmental pollutant 4-chloro-3-methylphenol (PCMC) using CV and square-wave voltammetry (SWV), respectively. Notably, the developed SWV procedure utilizing Bi-CCE exhibited significantly enhanced sensitivity (0.115 µA L mol−1), an extended linearity (0.5–58.0 µmol L−1), and a lower limit of detection (0.17 µmol L−1) in comparison with the unmodified electrode. Furthermore, the Bi-CCE was utilized effectively for the detection of PCMC in a river water sample intentionally spiked with the compound. The selectivity toward PCMC determination was also successfully assessed. [ABSTRACT FROM AUTHOR]

• Novel NaNO 3 -based electrolyte with acetic acid additive for Mg-air batteries. • Anode efficiency boost and significant extension of cell lifespan beyond 360 h. • Reduction of Mg anode corrosion and hydrogen evolution reaction. • Crucial surface chemistry and morphology transformations revealed. Mg-air batteries have attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical volumetric energy density, environmental sustainability, and cost-effectiveness. However, the fast hydrogen evolution reaction (HER) in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity, low energy density, and low utilization. Thus, the conventionally used NaCl solute was proposed to be replaced by NaNO 3 and acetic acid additive as a corrosion inhibitor, therefore an electrolyte engineering for long-life time Mg-air batteries is reported. The resulting Mg-air batteries based on this optimized electrolyte demonstrate an improved discharge voltage reaching ∼1.8 V for initial 5 h at a current density of 0.5 mA/cm2 and significantly prolonged cells' operational lifetime to over 360 h, in contrast to only ∼17 h observed in NaCl electrolyte. X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid addition. The thorough studies of chemical composition and morphology of corrosion products have allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries. [ABSTRACT FROM AUTHOR]

This study aims to improve the pore volume and specific surface area of kaolinite (Kaol) and montmorillonite (Mt) through low-temperature acid treatment to address their limited adsorption capacity. Clay mineral samples underwent sulfuric acid activation at various concentrations and durations. SEM analysis indicated acid activation improved kaolinite pore structure, increasing specific surface area, while montmorillonite exhibited reduced grain size and higher porosity, resulting in greater pore volume and surface area. EDX analysis revealed changes in chemical composition, including a 10% increase in silica and a 13% reduction in aluminium in kaolinite, whereas montmorillonite exhibited a 13% aluminium increase and 9.5% higher silica content. Kaolinite's XRD pattern remained unchanged, resisting 2.5 M acid activation, while montmorillonite displayed modified patterns, indicating interlayer conversion with increased acid concentration. BET analysis confirmed higher sulfuric acid concentration increased pore volume and surface area, while FTIR analysis showed stable Si–O stretching peaks with changing intensity after 8 h. Montmorillonite exhibited Al–OH and Mg–OH bands, decreasing with higher acid concentration, and Si–O–Fe and Si–O–Al bonds disappeared with acid activation. Thus, the results indicate significantly enhanced pore volume and specific surface area after acid activation, accelerating CO2 adsorption rates. This activation demonstrates a direct relationship between acid concentration and reaction time with clay minerals' pore characteristics. These clay minerals can be used as adsorbents for CO2 in carbon capture technology, aiding the global goal of achieving 'net zero' emissions by 2050. [ABSTRACT FROM AUTHOR]

Polymers play a crucial role in multiple industries; however, surface modification is necessary for certain applications. Exposure to non-thermal plasma provides a viable and environmentally beneficial option. Fused deposition molding utilizes biodegradable polylactic acid, although it encounters constraints in biomedical applications as a result of inadequate mechanical characteristics. This study investigates the effects of atmospheric pressure plasma generated by a dielectric barrier discharge system using helium and/or argon on the modification of polylactic acid surfaces, changes in their wettability properties, and alterations in their chemical composition. The plasma source was ignited in either He or Ar and was tailored to fit the best operational conditions for polymer exposure. The results demonstrated the enhanced wettability of the polymer surface following plasma treatment (up to 40% in He and 20% in Ar), with a marginal variation observed among treatments utilizing different gases. The plasma treatments also caused changes in the surface topography, morphology, roughness, and hydrophilicity. Plasma exposure also resulted in observable modifications in the dielectric characteristics, phase transition, and structure. The experimental findings endorse the utilization of plasma technologies at normal air pressure for environmentally friendly processing of polymer materials, specifically for applications that necessitate enhanced adhesion and have carefully selected prerequisites. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental research and surface characteristics after the process of roller burnishing of macro-asperities of the surface. As part of the work, the possibility of plastic shaping of the surface macrostructure with indentations (plateau structure), which will show anti-wear properties through appropriate surface shaping and the compressive stress state in the product's top layer, was investigated. The essence of the paper is to present the analysis of the surface roughness parameters and carry out analysis of SEM, AFM and metallographic results for the burnished surface. The main objective of the work is to develop an adequate outline of the surface to receive the required parameters and characteristics of the surface after burnishing. The results of dependencies of roughness parameter after turning and after burnishing from the vertical angle of asperities are presented, as well as SEM, AFM and metallographic analysis for the surface with a vertical angle of 60 ÷ 150 degrees. [ABSTRACT FROM AUTHOR]

Water contamination by arsenic (As) is widespread and is posing serious health threats globally. Hence, As removal techniques/adsorbents need to be explored to minimize potentials hazards of drinking As-contaminated waters. A column scale sorption experiment was performed to assess the potential of three biosorbents (tea waste, wheat straw and peanut shells) to remove As (50, 100, 200 and 400 µg L−1) from aqueous medium at a pH range of 5–8. The efficiency of agricultural biosorbents to remove As varies greatly regarding their type, initial As concentration in water and solution pH. It was observed that all of the biosorbents efficiently removed As from water samples. The maximum As removal (up to 92%) was observed for 400 µg L−1 initial As concentration. Noticeably, at high initial As concentrations (200 and 400 μg L−1), low pH (5 and 6) facilitates As removal. Among the three biosorbents, tea waste biosorbent showed substantial ability to minimize health risks by removing As (up to 92%) compared to peanut shells (89%) and wheat straw (88%). Likewise, the values of evaluated risk parameters (carcinogenic and non-carcinogenic risk) were significantly decreased (7–92%: average 66%) after biosorption experiment. The scanning electron microscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray and X-ray diffraction analyses confirmed the potential of biosorbents to remediate As via successful loading of As on their surfaces. Hence, it can be concluded that synthesized biosorbents exhibit efficient and ecofriendly potential for As removal from contaminated water to minimize human health risk. [ABSTRACT FROM AUTHOR]