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The in situ growth dynamics of colloidal silver–gold core–shell (Ag@Au CS) nanoparticles (NPs) are studied using time-dependent second harmonic generation (SHG) and extinction spectroscopy. Four sequential additions of chloroauric acid, sodium citrate, and hydroquinone are added to a silver nanoparticle solution to form a gold shell around a 45 nm silver core under different reaction conditions, resulting in final sizes ranging from 80 to 125 nm in diameter. In the first addition, a bumpy, urchin-like surface morphology is produced, while the second, third, and fourth additions provide additional nanoparticle growth with the surface morphology becoming more smooth and uniform, as shown using transmission electron microscopy measurements. The in situ extinction spectra increase in intensity for each addition, where blue-shifting and spectral narrowing are observed as the Ag@Au CS NPs grow in size. The extinction spectra are compared to Mie theory simulations, showing general agreement at later stages of the reactions for smooth CS surfaces. The in situ SHG signal is dominated by surface-enhanced plasmonic hotspots at the early stages of the shell growth, followed by gradual decreases in signal as the surface becomes more smooth. Two-photon fluorescence is also monitored during the CS growth, showing complementary information for comparisons to the extinction and SHG results. The holistic study of the synthesis and characterization of Ag@Au CS nanoparticles using in situ SHG spectroscopy, extinction spectroscopy, and Mie theory simulations allows for a comprehensive analysis of the complex growth dynamics occurring at the nanoscale for developing optimized plasmonic nanomaterial properties. [ABSTRACT FROM AUTHOR]

Nonpolar (100), polar (002), semipolar (101), and nonpolar (110) preferred oriented ZnO films were synthesized by regulated growth using the chemical bath deposition method. The crystallinity, surface morphology, and optical properties of ZnO films with different preferred orientations after annealing in different atmospheres were systematically investigated. The experimental results show an increase in crystallinity and a decrease in surface roughness of the films after annealing; in particular, the optical transmittance of semipolar (101) preferred oriented ZnO films was significantly higher than that of the other samples. XPS and PL spectra confirmed that annealing in argon effectively increased donor defects, whereas annealing in oxygen and ozone reduced donor defects in the films, and that ozone annealing was best suited to enhance acceptor defects in nonpolar (110) preferred oriented ZnO films. Argon annealing is the best for the enhancement of donor defects in polar (002) preferred oriented ZnO films. This work achieves modulation of optical properties and defects of ZnO films by annealing in different atmospheres, which provides new ideas for the application of ZnO materials. [ABSTRACT FROM AUTHOR]

In this study, Pb(Zr0.54Ti0.46)O3 films were prepared by the sol-gel method with Sm doping concentrations of 0, 0.5, 1, 1.5, 2, and 3 mol. %. Their surface morphology, density, crystal structure, piezoelectric, dielectric, and ferroelectric properties were characterized. The results indicated that, unlike Sm-doped lead zirconate titanate (PZT) ceramics, all Sm-PZT films exhibit a significant increase in the grain size compared to undoped PZT films. Moreover, Sm doping affected their crystal orientation and significantly enhanced their piezoelectric coefficient d33 and remnant polarization (Pr). Notably, the Sm-PZT film with a doping concentration of 1.5 mol. % exhibited optimal (100) orientation, achieving a high piezoelectric coefficient d33 of 279.87 pm/V, 4.55 times that of the non-doped PZT films. [ABSTRACT FROM AUTHOR]

We conduct molecular dynamics simulations of helium in tungsten to study the interaction of helium with grain boundaries. Model systems with grain boundary planes perpendicular to the surface and parallel to the surface are considered. The net attraction of mobile helium to the grain boundary results in a "depleted region" within approximately 3.5 nm of the grain boundary plane at low fluence, and once on the plane of the grain boundary, helium transport slows considerably. Helium retention is also strongly affected by the grain boundaries and their density: grain boundary planes approximately 6 nm beneath the plasma-facing surface and parallel to the surface tend to reduce the maximum bubble size due to the attraction of mobile clusters to the grain boundary plane, which lowers the concentration of helium near the surface (where it is being implanted); grain boundaries perpendicular to the surface tend to increase retention due to retention on the grain boundary plane. For grain boundaries parallel to the surface, the strong gettering effect of the grain boundaries on helium results in essentially no helium penetration through the grain boundary during the first 1.5 μs of plasma exposure at a flux of 1.6 × 10 25 m − 2 s − 1 , corresponding to fluences on the order of 10 20 m − 2 . Coarse-grained simulations capable of capturing the long-term dynamics of helium aggregation near grain boundaries would be required to determine whether these effects would have any measurable impact on phenomena, such as tungsten fuzz growth. [ABSTRACT FROM AUTHOR]

We report about metalorganic vapor phase epitaxy of smooth nitrogen-polar AlN templates on vicinal (0001) sapphire substrates. The influence of the V/III ratio, growth temperature, growth rate, as well as sapphire-nitridation time and temperature, were studied. With 4° offcut sapphire, step-flow growth was possible only with V/III ratios below 2. However, the optimal V/III ratio required precise adjustment, possibly dependent on reactor history and geometry. A rather narrow temperature window of less than 40 °C existed for smooth surface morphology. Reducing the temperature affected adatom mobility, eventually disrupting step-flow growth; increasing the temperature favored the formation of high-aspect-ratio defects on the epilayer. A low thermal-budget nitridation step with a short nitridation time of 15 s proved to be effective in controlling polarity without inducing excessive surface damage on the sapphire substrate. The growth rate also influenced surface morphology, with an increase in RMS roughness and step-bunching for faster growths until at growth rates above 1.4 μm/h step-flow growth could no longer occur. Finally, we developed a V/III ratio fine-tuning procedure, whereby the reactor-specific value that induces optimal growth is inferred by growth-rate variations. With this method, N-polar AlN templates with sub-nanometer RMS roughness were demonstrated for both 4° and 2° offcut sapphire substrates. [ABSTRACT FROM AUTHOR]

Face-to-face annealed and sputter-deposited aluminum nitride (FFA Sp-AlN) has potential in deep-ultraviolet light-emitting devices. Herein, the effects of the substrate off-cut angle (θsub) from an r-plane sapphire toward the c-axis projection direction and sputtering temperature (Tsp) on the crystallinity and surface morphology of a-plane AlN films are investigated. Increasing θsub in the minus-off direction, which occurs when the substrate surface approaches the sapphire c-plane, and lowering Tsp suppress the mixing of anomalous non-a-direction oriented domains. This reduced mixing enhances the surface flatness and crystallinity of a-plane FFA Sp-AlN. Moreover, the c-axis direction of the a-plane AlN film is inverted depending on the substrate off-cut angle. Ab initio calculations indicate that the interface stability between the r-plane sapphire substrate and the a-plane AlN film can explain the dependence of the crystallinity and c-axis orientation of FFA Sp-AlN on the surface off-cut of the r-plane sapphire. [ABSTRACT FROM AUTHOR]

Identifying the oxidation structure of two-dimensional interfaces is crucial to improve surface chemistry and electronic properties. Beyond graphene with only phenyl rings, a novel carbon-nitrogen material, C3N, presents an intrinsic heterogeneous surface morphology where each phenyl ring is encircled by six nitrogen atoms, yet its atomistic oxidation structure remains unclear. Here, combining a series of density functional theory calculations and ab initio molecular dynamics simulations, we demonstrate that thermodynamically favorable oxidation loci are confined to the phenyl ring, and kinetic transformations of oxidation structures are feasible along the phenyl ring, whereas those toward nitrogen atoms are proven to be extremely difficult. These results are attributed to the lower barrier of oxygen atom migration along the phenyl ring, while the significantly high barriers toward nitrogen atoms are due to the heterogeneous potential energy surface for oxygen–C3N interaction. This work highlights the significance of surface morphology on the characteristics of oxidation structure, offering insights into tunable electronic properties via confined interfacial oxidation. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate the in situ characterization of optical micro/nano fibers (MNFs). The MNF (test fiber, TF) is positioned on a microfiber (probe fiber, PF) and simulated for the scattering loss at various PF and TF diameters. The TF is fabricated using chemical etching technique. The PF is a conventional single-mode fiber with an outer diameter of 125 μ m. We measure the scattering loss along the TF axis at various positions i.e., diameters by mounting it on the PF. The diameter profile of the TF is inferred from the measured scattering loss and correlated with its surface morphology measurement. This work demonstrates an effective, low-cost, and non-destructive method for in situ characterization of fabricated MNFs. It can detect and determine the irregularities on the surface of OMNFs. It can also be used to quantify the local evanescent field. Detecting such local points can improve studies that are carried out using these fields in various sensing and related study domains. It is simple to implement and can be accessed by all domains of researchers. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate an in situ etch technique for β-Ga2O3 inside a metalorganic chemical vapor deposition (MOCVD) reactor using triethylgallium (TEGa) as the etching agent. At sufficiently high substrate temperatures (Tsub), TEGa is introduced into the MOCVD reactor which undergoes pyrolysis, resulting in the deposition of Ga on the β-Ga2O3 surface. These Ga adatoms react with Ga2O3 to form gallium suboxide (Ga2O), which desorbs from the β-Ga2O3 surface resulting in the etching of the epilayer. MOCVD chamber parameters such as TEGa molar flow rate, substrate temperature, and chamber pressure were shown to be key in controlling the etch rate and surface morphology. A wide range of etch rates from ∼0.3 to 8.5 μm/h is demonstrated by varying the etch parameters. In addition, smooth surface morphology on (010) and (001) β-Ga2O3 substrates is also demonstrated. This new etch technique could enable damage free fabrication of 3D structures like fins and trenches, which are key components in many β-Ga2O3 device structures. [ABSTRACT FROM AUTHOR]

We investigated the chemical beam epitaxy of GaP 1 − x N x grown on nominally (001) -oriented Si substrates, as desired for the lattice-matched integration of optoelectronic devices with the standard Si technology. The growth mode and the chemical, morphological, and structural properties of samples prepared using different growth temperatures and N precursor fluxes were analyzed by several techniques. Our results show that, up to x ≈ 0.04 , it is possible to synthesize smooth and chemically homogeneous GaP 1 − x N x layers with a high structural quality. As the flux of the N precursor is increased at a given temperature to enhance N incorporation, the quality of the layers degrades upon exceeding a temperature-dependent threshold; above this threshold, the growing layer experiences a growth mode transition from 2D to 3D after reaching a critical thickness of a few nm. Following that transition, the morphology and the chemical composition become modulated along the [ 110 ] direction with a period of several tens of nm. The surface morphology is then characterized by the formation of { 113 } -faceted wires, while the N concentration is enhanced at the troughs formed in between adjacent (113) and (1 ¯ 1 ¯ 3). On the basis of this study, we conclude on the feasibility of fabricating homogeneous thick GaP 1 − x N x layers lattice matched to Si (x = 0.021) or even with N content up to x = 0.04. The possibility of exceeding a N mole fraction of 0.04 without inducing coupled morphological–compositional modulations has also been demonstrated when the layer thickness is kept below the critical value for the 2D–3D growth mode transition. [ABSTRACT FROM AUTHOR]

This work highlights the influence of surface properties, on the characteristics of InAlN/GaN based high electron mobility transistor (HEMT) structures grown on the SiC substrate by metalorganic vapor phase epitaxy. The growth parameters, i.e., reactor pressure and V/III ratio were tuned to improve the morphological and two-dimensional electron gas (2DEG) characteristics of the HEMT structure. It was found that V/III ratio plays a significant role in improving surface morphology and 2DEG properties without altering average indium composition. It was also found that 2DEG properties are highly sensitive to surface morphology and its features. The step flow smooth surface morphology with very low surface and interface roughness was observed in optimized lattice-matched InAlN/GaN HEMT structures. The sheet resistance of ∼170 Ω/sq with good 2DEG concentration (∼2.4 × 1013 cm−2) and 2DEG mobility (∼1500 cm2/V s) was achieved in the optimized lattice-matched InAlN/GaN HEMT structure. A comparison between different barrier-based HEMT structures, i.e., lattice-matched InAlN/GaN and strained AlGaN/GaN, was also discussed. Their structural, electrical, morphological, and interfacial characteristics were compared. [ABSTRACT FROM AUTHOR]

This study aims to elucidate the possible application of cobalt aluminate nanoparticles (CoAl 2 O 4) as a photocatalyst for the removal of organic dyes. The sol-gel method was employed to synthesise Nd x /CoAl 2 O 4 nanoparticles with varying weight percentages (x = 0.0, 0.2, 0.4, and 0.6 wt %). The experimental investigation focused on the photocatalytic destruction of colour, employing a visible light irradiation source. The structural and optical properties of the synthesised nanoparticle were examined through various analytical techniques, including X-Ray Diffraction (XRD), Ultra Violet-Diffuse Reflectance Spectroscopy (UV-DRS), Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), Tunnelling Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). The cubic spinel structure was confirmed through the study of the X-ray diffraction (XRD) pattern of the Nd x /CoAl 2 O 4 nanoparticles. For the compositions x = 0.0, 0.2, 0.4, and 0.6, the nanoparticles exhibited average crystallite sizes of 23.73, 22.99, 21.69, and 21.65 nm, respectively. The synthesised nanoparticle exhibited heterogeneous photocatalytic potential when employed as a model pollutant for the oxidative destruction of crystal violet dye. The experimental findings validated that the CoAl 2 O 4 nanoparticle exhibited a dye degradation rate of 64 % during a 100-min timeframe. Additionally, the 0.6 wt % Nd CoAl 2 O 4 nanoparticle shows a quick dye degradation rate of 91 % for crystal violet dyes when exposed to visible light sources. Hence, the synthesised nanoparticle exhibits catalytic activity and holds potential for utilisation in the treatment of hazardous contaminants in industrial wastewater. [ABSTRACT FROM AUTHOR]

This paper presents a novel Fe 2 TiO 5 sensing material for ethanol and acetone detection. Pure Fe 2 TiO 5 nanomaterial was synthesized by a combined solvothermal and calcination method using ferrous sulfate as precursor and urea as a surfactant. The microstructure and surface morphology indicate that Fe 2 TiO 5 belongs to the orthorhombic crystal structure with a Bbmm space group and is composed of loose aggregates of irregular nanoparticles (20–30nm) and abundant pores. X-ray photoelectron spectroscopy analysis indicates that the Fe 2 TiO 5 aggregates contain mixed valence states of Fe2+ and Fe3+ and abundant oxygen vacancies. Examination of gas sensing properties suggests that Fe 2 TiO 5 is an excellent gas-sensitive material. Particularly, at a low optimum operating temperature (240 °C), the gas response of the Fe 2 TiO 5 aggregates to 100 ppm ethanol and acetone is as high as 84.1 and 220.9, respectively. The linear relationship between log(S-1) and logC indicates that Fe 2 TiO 5 can accurately detect ethanol and acetone over a wide concentration range. The gas-sensing performance of the novel Fe 2 TiO 5 nanomaterial can be explained based on the synergistic effect of oxygen vacancy defects and the characteristic surface morphology. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the effect of strontium (Sr) doping on the thermoelectric properties of thin films made of tin telluride (SnTe). The preparation of Sn 1-x Sr x Te (x = 0, 0.1, 0.2, 0.3, 0.4) films using a straightforward thermal evaporation method and subjected them to post-annealing at 773 K. The surface morphology and crystal structure of the films have been examined by using SEM and XRD, respectively. Our findings indicate that the Seebeck coefficient value increased from 39 to 68 μV/K as the Sr doping concentration increased. This enhancement has been attributed to the energy filtering effect resulting from charge carrier dislocation. However, the electrical conductivity value decreased due to an increase in defect density. The maximum enhancement of the power factor has been observed for x = 0.3, where the value reached 38.9 μWcm−1K−2, which is greater than the pristine sample. Our results conclude that Sr 0.3 doping in Sn 0.7 Te is a valuable addition for thermoelectric applications at room temperature. Additionally, the use of the simple thermal evaporation method for film preparation highlights its potential for large-scale applications. [ABSTRACT FROM AUTHOR]

This paper introduces a microbubbles flow electrolytic plasma polishing (MF-EPP), which is based on electrolytic plasma polishing (EPP), but allows for local control polishing. MF-EPP energy consumption is lower, only 70–90 W power supply can complete the processing. Using Ti-6Al-4 V alloy sample as the polishing object, design and construct the original prototype to conduct theoretical and experimental research on the polishing process. The results show that the polishing solution has a stable polishing performance at a voltage of 210–430 V, functioning as a flexible polishing head, forming a circular polishing area of 14 mm in diameter on the workpiece surface, and reducing the surface roughness of polishing area from Ra 0.546 to 0.081 µm within 180 s. The processing phenomena, voltage and current characteristics, and surface morphology of the specimen are analyzed. Importantly, macroscopic and microscopic "pin-plate" models are proposed to elucidate the formation mechanism of MF (microbubbles flow) and the polishing mechanism of MF-EPP. [ABSTRACT FROM AUTHOR]

Thin-walled carbon/carbon (C/C) composites are a typical difficult-to-machine material due to the characteristics of thin walls, low stiffness, and high strength. In this paper, three ultrasonic-assisted machining methods and surface morphology of C/C composite thin-walled small holes were studied. The influence of machining parameters on average axial force and hole surface morphology was explored by single-factor experiments and orthogonal experiments. A quantitative comparison was conducted to evaluate the machining defects of drilling, reaming, and grinding. The results of single-factor experiments showed that the surface quality of drilling initially improved and then deteriorated with the increase of spindle speed. Additionally, increasing feed rate resulted in a deterioration in surface quality, while increasing amplitude to a certain extent led to an improvement. In orthogonal experiments, the effect of ultrasonic amplitude on the average axial force of reaming and grinding was greater than that of drilling. In terms of surface quality, the minimum evaluation factor Qc of the grinding, reaming, and drilling could reach 1.0137, 1.0198, and 1.0253, respectively. Further optimized by a multivariate optimization function, the optimal parameters of grinding were obtained as the speed of 6200 r/min, feed rate of 40 mm/min, and amplitude of 8 μm and the minimum values of Qc could reach 1.0128. [ABSTRACT FROM AUTHOR]

High-k oxide dielectric films are indispensable for low-power-consumption oxide thin-film transistors (TFTs) applied in advanced and portable electronics. However, high-quality oxide dielectric films prepared by solution process typically require sophisticated processes and long thermal annealing time, severely limiting both the throughput manufacturing and cost-effectiveness. In this study, the influence of different heating-up methods on the surface morphology and dielectric properties was systematically investigated. Gradient heating-up method could not only substantially improve the surface morphology and quality of high-k ZrO2 films but also efficiently shorten the annealing time. The gradient heating-up process was further designed on the basis of thermal behavior of the xerogel-like precursor, which successfully realize the preparation of high-quality ZrO2 films with an annealing time of 5 min (i.e. the efficiency of thermal treatment increased by about 89%). The ZrO2 film presented excellent dielectric properties, including a low leakage current density of ∼10−8 A cm−2 (at 2 MV cm−1), a large areal capacitance of 169 nF cm−2 and a high dielectric constant of 20.41 (1 MHz). Furthermore, InSnZnO TFT based on the ZrO2 gate dielectrics shows an acceptable device performances, such as a high carrier mobility of 2.82 cm2 V−1 s, a high on/off current ratio of ∼105 and a low subthreshold swing of 0.19 V decade −1 at a low operation voltage of 5 V. This work provide a highly promising approach to fabricate high-quality solution-processed high-k oxide dielectric films employed for large-scale and low-power-consumption electronics. [ABSTRACT FROM AUTHOR]

AbstractThe current study aimed to evaluate the pharmacokinetics and neuroprotective effect of well-characterised berberine-bovine serum albumin (BBR-BSA) nanoparticles. BBR-BSA nanoparticles were generated by desolvation method. Entrapment efficiency, loading capacity, particle size, polydispersity index, surface morphology, thermal stability, and in-vitro release were estimated. In-vitro pharmacokinetic and tissue distribution were conducted. Their neuroprotection was evaluated against lipopolysaccharides-induced neurodegeneration. BBR-BSA nanoparticles showed satisfactory particle size (202.60 ± 1.20 nm) and entrapment efficiency (57.00 ± 1.56%). Results confirmed the formation of spheroid-thermal stable nanoparticles with a sustained drug release over 48 h. Sublingual and intranasal routes had higher pharmacokinetic plasma profiles than other routes, with Cmax values at 0.75 h (444 ± 77.79 and 259 ± 42.41 ng/mL, respectively). BBR and its metabolite distribution in the liver and kidney were higher than in plasma. Intranasal and sublingual treatment improves antioxidants, proinflammatory, amyloidogenic biomarkers, and brain architecture, protecting the brain. In conclusion, neuroinflammation and neurodegeneration may be prevented by intranasal and sublingual BBR-BSA nanoparticles. [ABSTRACT FROM AUTHOR]

In this study, Fe–Mn/activated carbon (AC) catalysts were prepared to investigate the CO + NH3 coupling for deducing the NO removal mechanism by iron and manganese supported on AC catalysts under moderate to low-moderate aerobic conditions. Through the catalyst surface morphology, phase analysis, and other test results, we propose a mechanism for the CO + NH3 coupling that results in NO removal at medium to low temperatures. The results indicate that NO conversion initially decreases and then increases in the range of 150–300 °C with 9% oxygen content. The NO conversion of the 3.5Fe–7.0Mn/AC catalyst reached 95%, surpassing other catalysts, with an inflection point near 230 °C. Characterization of the 3.5Fe–7.0Mn/AC catalyst revealed a smooth surface, uniform pore development, a high number of micro and medium pores, and elevated surface oxygen species (Oα) content. Mn2O3 and Fe3O4 are uniformly distributed on the surface, enhancing the reaction gas contact area and thereby improving NO conversion. Fe2+ is identified as the primary active site for NO removal. Increased Mn loading raises the Fe2+ and Mn3+ levels, with Mn3+ improving the NO conversion rate. [ABSTRACT FROM AUTHOR]

Defects, such as scratches, cleavage fracture, and cleavage pit, occur during surface processing and affect the surface integrity of β-Ga2O3(100) substrates. This study analyzes the effects of polishing materials (polyurethane, lead, and copper) and substrate surface temperatures (25, 10, and 0 ℃) on the polishing results to overcome the effects of such defects on the substrates. Vickers indentation tests were used to detect the effects of the material and surface temperature on the hardness of the disc and substrate, respectively. Machining was verified by conducting ball-disk friction wear and polishing experiments. The experimental results indicate that the material of the polished optical disc significantly affected β-Ga2O3(100) during surface processing. The higher the hardness of the polished optical disc, the greater the material removal rate (MRR) of the substrate surface, and more serious the surface cleavage phenomenon. A lead disc with lower hardness could be used to process β-Ga2O3(100) for realizing a higher MRR, thereby effectively avoiding cleavage fractures and obtaining a surface roughness (Ra) and scratch depth of 3.4 nm and 18 nm, respectively. The hardness and mechanical strength of the substrate could be enhanced at low temperatures, and the indentation depth would become smaller under the action of external forces, effectively inhibiting the formation of scratches and pits on the surface of the substrate during polishing. After polishing the substrate at 0 ℃, the Ra, scratch depth, and total number of cleavage pits were 2.2 nm, 14.3 nm, and 246 nm, respectively. Compared with 25℃, Polishing the substrate at 0 ℃ decreased the Ra, scratch depth, and number of cleavage pits by 35.3, 20.6, and 34.9%, respectively. At 0 ℃, the substrate effectively avoided cleavage fracture and inhibited scratch and pit formation, thereby significantly improving the polishing effect. [ABSTRACT FROM AUTHOR]

This study aimed to enhance compatibility and thermal stability between thermoplastic starch (TPS) and polylactic acid (PLA) by incorporating citric acid-grafted starch (CA–Starch) at different concentrations (1 and 5%) with varying degrees of substitution for starch derived from sweet potatoes and yams (DY). Blends were produced using a constant TPS/PLA weight ratio of 60:40, both with and without a compatibilizer. The blending process was carried out using a torque rheometer under two distinct conditions. The results exhibited reduced particle sizes in TPS60/PLA40/CA–Starch blends, as evidenced by SEM images displaying improved interaction and smoother surfaces. Significantly, one of the properties that experienced substantial improvement was the compatibility between TPS and PLA, as indicated by reduced phase segregation within the blends. This improvement manifested in enhanced surface morphology, smaller particle sizes, and greater homogeneity in the blends. Additionally, an enhancement in thermal properties, particularly thermal stability, was observed with higher CA content. This study underscores that the incorporation of CA–Starch not only enhances compatibility but also improves thermal stability in TPS60/PLA40 blends, offering potential for the development of biocompatible materials with superior performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • NH 4 PF 6 dual beneficial role, hinders the dendritic growth and accelerate the SEI formation. • Stable lithium deposition stripping over 1500 cycles. • Operando confocal Raman spectroscopy demonstrates the electrolyte degradation in forming the SEI. Lithium-ion batteries (LiBs) with graphite as an anode and lithiated transition metal oxide as a cathode are approaching their specific energy and power theoretical values. To overcome the limitations of LiBs, lithium metal anode with high specific capacity and low negative redox potential is necessary. However, practical application in rechargeable cells is hindered by uncontrolled lithium deposition manifesting, for instance, as Li dendrite growth which can cause formation of dead Li, short circuits and cell failure. The electrochemical behaviour of a protic additive (NH 4 PF 6) in a carbonate-based electrolyte has been investigated by operando confocal Raman spectroscopy, in situ optical microscopy, and X-ray photoelectron spectroscopy, elucidating its functional mechanism. The ammonium cation promotes a chemical modification of the lithium metal anode-electrolyte interphase by producing an N -rich solid electrolyte interphase and chemically modifying the lithium surface morphology by electrochemical pitting. This novel method results in stable lithium deposition and stripping by a decreasing the local current density on the electrode, thus limiting dendritic deposition. [ABSTRACT FROM AUTHOR]

The presented work explores detail information about surface modification of BNNTs with ZrO 2 through isothermal hydrolysis process for reducing its hydrophobic property and enhancing the wettability as BNNTs possess hydrophobicity & poor wettability in its raw form as it agglomerates during fabrication of composites, ultimately prohibits usage of BNNTs as a prime reinforced material and for other utilization. HRTEM, EDX, E.M confirmed thin coating layer of ZrO 2 whereas X-ray diffraction and FE-SEM determined the morphological structure of BNNTs in its raw form comparing with properties of BNNTs@ZrO 2. Contact angle test displays increased wettability of synthesised BNNTs where Zeta Potential provides upgraded stability and dispersibility of coated BNNTs in aqueous medium. Confirmation of coating, improved surface architecture and chemical properties of coated BNNTs than non-treated BNNTs is observed via FTIR. BNNTs@ ZrO 2 showing thermally stable and constant throughout temperature beyond 800 °C through TGA. Present study describes the features of BNNTs and BNNTs@ZrO 2 enriching morphological and thermal characteristics followed by confirmation of coating layer through isothermal hydrolysis process, improvement in wettability and hydrophobicity for further future approach towards reinforcement in MMCs, in a nut shell very effectively applicable in aerospace and automobile industrial utilization. [ABSTRACT FROM AUTHOR]

Potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy methods were used to investigate the inhibitory effects of 1-methyl-1-propyl-piperidinium bromide (MPPB) on the corrosion inhibition of 6061 aluminium alloy in the presence of 0.01 M HCl. The results of PDP studies indicate that MPPB behaved as a mixed inhibitor. The inductive loop in the Nyquist plot implies the adsorption of MPPB on the surface of 6061 aluminium alloy. Scanning electron microscope and atomic force microscopic analysis indicated the adsorption of MPPB on the surface of 6061 aluminium alloy by smooth surface in the presence of MPPB. The percentage composition of aluminium is found to be more in the presence of MPPB than in the absence of MPPB in a corrosive medium, which implies adsorption of MPPB on 6061 aluminium alloy. From PDP studies, it is evident that MPPB gave a maximum inhibition efficiency of 73.95% in 0.01 M HCl for 400 ppm of MPPB at 303 K. [ABSTRACT FROM AUTHOR]

The study of chip morphology during high-speed milling is crucial in determining processing quality, but the relationship between chip formation mechanisms and process parameters in titanium alloy high-speed machining has been a difficult issue. This paper investigates milling force and temperature variation, as well as chip morphology and surface quality after milling to improve workpiece surface quality and machining efficiency and provide guidance on selecting milling parameters. Factorial analysis confirms that milling speed worsens the serrated layer of chips. In addition, the experiment confirms the influence of tool rake angle on shear strain in the milling zone, the impact of rotational speed on tool wear, and the effect of tool wear on chip morphology. The results show that increasing milling speed worsens chip serration and increases tool wear. [ABSTRACT FROM AUTHOR]

In this investigation, the factors were oil type ( O t ), powder type ( T p ), and powder concentration ( C p ) level, and the machining parameters were the voltage (V), capacitance (pf), pulse-on time ( T on ), and pulse-off time ( T off ). The output parameters were the material removal rate (MRR), and tool wear rate (TWR). Three types of oils and powders, along with their respective particle concentrations, were selected for this experiment. Neem, Karanja, and sesame oils were mixed with aluminum oxide (Al2O3), chromium (Cr), and nickel (Ni) powder at 4, 6, and 8 gm/l, respectively, using an overhead stirrer to investigate the conditions under which the green oil powder mixed mixture yielded a higher MRR and lower TWR during the micro-EDM process of titanium alloy (Ti-6Al-4V) using a 0.8 mm tungsten carbide (WC) tool with fixed machining parameters (240 V, 100 pf, 20 μ s T on , and 5 μ s T off ). All the powders used in this experiment had a 32-micron (450 mesh) size. The Taguchi L 2 7 orthogonal array and grey relational analysis methods were used to design and optimize the input process parameters for both responses. SEM, optical microscopic analysis, and EDS analysis were performed to examine the surface morphology, characteristics of the WC tool, and elemental composition of both the tool and the workpiece material. The optimum conditions for Karanja oil with a Cr powder mixture concentration of 4 g/l resulted in higher MRR and lower TWR. However, machining with neem and sesame oils resulted in higher TWR and lower MRR. [ABSTRACT FROM AUTHOR]

Silicon carbide particle–reinforced aluminum matrix (SiCp/Al) composite materials are challenging to machine, leading to significant surface quality issues arising during milling. In this study, a single-factor experiment was conducted using carbide-coated tools to mill SiCp/Al composite materials with a 45% volume fraction of silicon carbide particles (SiCps). Scanning electron microscopy, roughness measuring instruments, and a three-dimensional optical profiler were employed to investigate the formation mechanisms of the machined surface morphologies, as well as the effects of milling parameters (milling speed, feed per revolution, and milling depth) on the surface micro-morphology of the SiCp/Al composite materials. This study assessed the suitability of various roughness characterization parameters for evaluating the milled surface of SiCp/Al composite materials, including the two-dimensional profile arithmetic mean deviation (Ra), profile root mean square deviation (Rq), and microscopic surface roughness 10-point height (Rz), as well as the three-dimensional arithmetic mean deviation of the surface profile (Sa), and root mean square deviation of the surface profile (Sq) roughness characterization parameters to evaluate the milled surface of the SiCp/Al composite materials. The findings suggest that the three-dimensional roughness characterization parameters more accurately reflected the changes in the surface roughness than the two-dimensional ones. When the milling speed increased from 0.05 to 1.2 mm/rev, Sa first decreased from 0.514 to 0.498 µm and then increased to 0.537 µm, while Sq first decreased from 0.637 to 0.616 µm and then increased to 0.658 µm. Ra, Rz, and Rq all increased with higher values of feed per revolution and milling depth. [ABSTRACT FROM AUTHOR]

The mixing of N3 and N719 metal-complex dyes was investigated in this work to determine the effects of the combination of dyes on TiO2film for application in dye-sensitized solar cells (DSSCs). The dyes were mixed in a ratio of 1:1, and their performance in the DSSCs was measured using current–voltage curves and electrochemical impedance spectroscopy (EIS). The results indicated that the efficiency of the DSSCs increased to 7% with the addition of the N719 dye to the N3 dye. The surface morphology revealed a smooth and homogeneous distribution of TiO2 nanoparticles, and the mixed dyes showed broad absorption spectra in the visible region. The EIS results indicated a low electron recombination rate and long electron lifetime for the mixed dye-sensitized solar cells. Overall, the study demonstrated the potential for using a combination of N3 and N719 dyes to improve the efficiency of DSSCs. The employment of mixed dye as a photosensitizer in DSSCs may offer a promising approach for achieving high-performance and cost-effective DSSCs. [ABSTRACT FROM AUTHOR]

In the current scenario, industries face new challenges in cutting metal-based composites with good surface texture. The experimental investigation on laser cutting of magnesium AS2-Bimodal SiC composites is reported in the present work. Three bimodal compositions with varying proportions of micro-nano SiC reinforcement (75%-25%, 50%-50% and 25%-75%) were dispersed in AS21 alloy by stir-casting route. The comparison of quality characteristics such as surface roughness, kerf deviation and edge slope has been done to examine the behaviour of bimodal reinforcement with different laser cutting parameters. The experimental strategy was implemented based on the Taguchi L18 mixed design. The microstructure and cutting surface morphology has been analysed using OM, SEM and TEM. The results demonstrated that the AS21 composite with a bimodal structure of 75 vol.% micro-SiC and 25 vol.% nano-SiC showed better performance characteristics of CO2 laser cutting system due to uniform grain structure and homogeneous dispersion of nano-SiC reinforcement. [ABSTRACT FROM AUTHOR]

In the modern era, manufacturers aim for their parts to possess a sleek finish and increased durability to ensure continued functionality. Both the automotive and aerospace industries are actively seeking new materials and methodologies to enhance the surface quality of components during the preparation process and make the most of available resources. Employing casting, advanced techniques, and new materials is crucial for achieving this goal. Industries commonly utilize alloys and composite materials in the production of their components. This study focuses on magnesium composite Mg-4Zn-1RE-0.7Zr alloy to find the influence of varying three different reinforcement particles on mechanical properties and wear rate. An attempt was made to choose a constant 5% Si3N4 as the primary reinforcement and 2.5% to 7.5% of TiC/MoS2 as the secondary reinforcement, respectively. The samples of magnesium hybrid composites are prepared using a centrifugal casting process. The ZE 41 alloy/5% (TiC-MoS2)/5%Si3N4 has a high tensile strength of 942 MPa. In addition, 5% TiC/5% MoS2 with 5% Si3N4 composite has enhanced hardness, which is beneficial for transmission in aircraft like Boeing 727 and die-casting fittings in automobile applications. [ABSTRACT FROM AUTHOR]

Zinc(II) bis(dithiocarbamate), hereafter ZnBz, material has been synthesized and used to fabricate humidity sensor. Structure of the ZnBZ compound was confirmed using the FT-IR, IH NMR, and 13C NMR spectroscopy techniques. The whitish color solution of ZnBz materials was deposited between the Ag-electrodes via drop-casting technique. The surface morphology of the material was studied using scanning electron microscopy (SEM) technique. The SEM images show that the thin film surface of the material possessed petals and hexagonal plates along with pores and pore-channels. The fabricated sensor was checked at different frequencies. The capacitive, resistive, and hysteric behavior of the sensor was studied at different humidity levels and different applied frequencies. Capacitance of the sensor was enhanced from 14 to 18 nF when humidity was changed from 30%RH to 90%RH keeping applied frequency constant at 120 Hz. However, at 1 kHz, the capacitance was increased from 145 to 355 pF in similar humidity range, while resistance was dropped from 3.5 MΩ to 282 kΩ at 120 Hz, and from 159 GΩ to 2.44 GΩ at applied frequency of 1 kHz. The response/recovery time was 81.7/60.7 s. Curve with two different slopes was obtained due to the switching from chemisorbed to physisorbed mode. The values of the goodness of fit, R2, were 0.991 and 0.989 for chemisorbed and physisorbed layers. The sensor showed stable response over time. The maximum hysteresis, H max , values were 0.042% and 5.15% at applied frequencies of 120 Hz and 1 kHz, respectively. [ABSTRACT FROM AUTHOR]

The protection of boiler tubes against erosion caused by fly ash is essential for maintaining boiler efficiency. This study proposes a metallic coating based on Fe–Cr-B-Mn, applied using the electric arc thermal spray technique, as an alternative for protecting the most impacted areas of boiler tubes from ash erosion. The impact of different surface finishes, obtained through grinding, on the erosive wear resistance of the coating was analyzed. The electric arc thermal spray was performed manually at an angle between the gun and the plate of 90 degrees, in atmospheric air. The coating's surface roughness (Ra) was measured with a rugosimeter, in 2 preferential directions, and was found to have values between 11 and 17 μm. Grinding was chosen as the machining process due to its efficiency in finishing thermally sprayed surfaces. Three conditions were analyzed: as-coated (Ra = 13.08 µm), the intermediate surface finish (Ra = 2.495 µm), and the surface fine finish (Ra = 0.486 µm). Samples in all conditions were submitted to erosion tests according to ASTM G76, using alumina blasting. The surface was examined by scanning electron microscopy (SEM). The morphology of machining scars demonstrated a brittle failure mode of material removal during grinding. Additionally, the cross-section was investigated using optical microscopy. Abrasive wear tests presented average erosion rates of 3.038 × 10−5 g/s, 2.23574 × 10−5 g/s, 2.77325 × 10−5 g/s for fine, intermediate, and as-coated finishes, respectively. The results guided the optimized selection of materials and processes to protect boiler tubes from fly ash impact. [ABSTRACT FROM AUTHOR]

Axial ultrasonic vibration-assisted micro-milling (UVAM) has emerged as an advanced technique that can be tailored to improve the machinability of difficult-to-machine materials such as 316L stainless steel. This article sets out to meticulously compare and analyze the cutting performance of conventional milling (CM) and UVAM techniques in the side milling of 316L stainless steel. The cutting separation characteristics of UVAM of 316L stainless steel are elucidated, and the air-cutting ratio in UVAM is introduced. The relationship between the air cutting ratio and spindle speed is also derived. Based on theory, the finite element simulation and experiments are compared under both milling conditions. An analysis of the results for these two sections is presented to validate the theoretical derivation. The results show that the trend and analysis of the experimental cutting forces are aligned with those in the simulation. The cutting forces also confirm the reliability of the simulation results. Due to factors such as tool wear, there is a deviation of 5–20% between the experimental values and the simulation results. A chip variation analysis in the simulation also corresponds to the trend in cutting temperature. An evaluation of the surface morphology and roughness of the experimental samples reveals that the surface quality and smoothness under UVAM are superior to those under CM. Tool wear analysis indicates that the carbide tool undergoes severe wear in the side milling of 316L stainless steel. In summary, the simulation and experiments convincingly demonstrate the advantages of UVAM technology and provide a reference for optimizing the milling process of challenging materials. [ABSTRACT FROM AUTHOR]

Microelectrochemical systems (MEMSs) have important applications in electronic information, aerospace, national defense and other fields. The microhemispherical concave die is the manufacturing foundation for the MEMS system. To clarify the forming mechanism of microhemispherical concave dies machined by microultrasonic machining with ceramic whole ball tools, a material removal model was presented. Furthermore, the kinetic energy model of a spherical abrasive under the action of microultrasonic and whole ball ceramic tools was also established. The model of the brittle-plastic transition removal mode is correlated with the kinetic energy of the abrasive model. The surface morphology of miniature molds exhibits significant variations attributed to the altered material removal mode, the removal mechanism was analyzed. The theoretical model is verified by experiments. Experiments were performed with lower and higher viscosity polishing fluids. The surface roughness of the plastic removal area in each group was 96.4 and 60.1 nm. Due to the high viscosity polishing fluid eliminating some of the cavitation phenomena, the overall surface quality is improved; hence, the surface roughness decreases by 37.6% under the same processing conditions. In the low-viscosity experimental group, the surface roughness was 113.61, 302.28 and 367.24 nm, respectively. The experimental verification confirmed that variations in surface morphology occur, even with the same removal mode applied at different locations on the microconcave die. The reasons for the surface roughness variation in different areas of the microconcave die are analyzed and reveal the influence of ultrasonic cavitation on the material removal mode in microultrasonic machining. [ABSTRACT FROM AUTHOR]

Biogenic combustion with Mellifera (Honey) capping produced ZnO, Ag-doped ZnO, and Fe-doped ZnO nanoparticles. The phase and crystal structure of metal oxide nanoparticles (MONPs) have been recorded through XRD spectrum. It confirms that the prepared metal oxides are within the nanoscale range. The average crystallite size of Fe-doped ZnO is 8.8 nm, smaller than ZnO and Ag-doped nanoparticles. The vibrational spectra of ZnO, Ag-doped ZnO, and Fe-doped ZnO nanoparticles confirm functional group stretching vibrational modes. The exterior surface morphology of all metal oxide nanoparticles was captured by FESEM. Metal oxide nanoparticle compositional analysis shows elemental presence, atomic, and weight %. The optical properties of metal oxide nanoparticles have been examined using UV–vis spectroscopy. The band gap energy of ZnO nanoparticles reduced from 2.68 eV to 1.74 eV under Fe doing and increased to 2.9 eV under Ag doing. Metal oxide thermal stability is also being investigated to determine how it affects ZnO nanoparticles. Fe-doped ZnO nanoparticles have greater sensor properties than other metal oxides due to their tiny size, band gap, and stability. Gas sensor behaviour of three metal oxide nanoparticles was examined in various accepts. It proves Fe-doped ZnO is a promising gas sensor material. [ABSTRACT FROM AUTHOR]

In this study, corrosion control of mild steel in acidic media was conducted in the presence of polyvinyl alcohol (PVA)‐chitosan and PVA‐chitosan‐dopamine composite coatings. Weight loss, polarization, and electrochemical impedance spectroscopy (EIS) studies were conducted to study the protective mechanisms and performance of PVA‐chitosan coatings. The results showed a substantial reduction in weight loss, corrosion rates, and corrosion current densities for coated specimens indicating the effectiveness of the composite coatings. PVA‐chitosan and PVA‐chitosan‐dopamine coatings showed high inhibition efficiencies (IE) up to 90.65 % and 96.01 % respectively. The electrochemical findings were supported using surface characterization techniques such as SEM to obtain a complete understanding of the coatings' morphology and composition. The topographical analysis confirmed that dopamine significantly influenced the surface morphology and behavior of the nanocomposite. The FTIR spectrum of composite B, which combined PVA and chitosan, exhibited notable changes, including a decrease in both the intensity and frequency of the OH band. The potential of PVA‐chitosan‐dopamine coatings as effective corrosion inhibitors for mild steel in acidic environments offered practical solutions for diverse industrial applications. [ABSTRACT FROM AUTHOR]

In this study, multifunction cavitation (MFC) was performed on low‐alloy steel (AISI 4140 steel) rods with different hardnesses to increase their fatigue limit. It was found that a high compressive residual stress was generated on the surface of steel rods by MFC and that the magnitude of the compressive residual stress tended to increase with increasing specimen hardness, which resulted in a higher fatigue limit. However, fatigue cracks are known to be initiated from the pits and red rust that form on the surface during MFC treatment in water. Furthermore, relaxation of the compressive residual stress was also investigated during the fatigue test to elucidate the mechanism for improving the fatigue properties. The results showed that the fatigue limit for MFC‐treated steel rods was accurately estimated by considering residual stress relaxation, hardness, and pit formation. Validation of the fatigue limit estimation was also conducted through comparison with Murakami's equation. [ABSTRACT FROM AUTHOR]

Although significant efforts have been undertaken to explore the toughening of epoxy resins, it remains challenges to establish a simple and effective toughening technique which does not compromise its strength, thermal stability and processing performance. In this paper, toluene‐diisocyanate‐trimer (TDI‐T) was utilized to manufacture a novel epoxy‐terminated dendritic modifier TDI‐T glycol diglycidyl ether (TDI‐T GLDE). When the addition of TDI‐T GLDE reaches 20% of the resin mass, the tensile strength, tensile elongation, compressive strength and impact strength were increased by 28.1%, 75%, 24.8%, and 138.0% respectively, compared to E‐51. The thermal properties of the samples have been improved, including an increased glass transition temperature (Tg) from 68.2 to 73.2°C, as well as an increase in the initial decomposition temperature from 240.6 to 257.7°C. The toughening mechanism of TDI‐T GLDE was studied through a combination of mechanical performance tests, thermal performance tests, and resin fracture surface morphology analysis. [ABSTRACT FROM AUTHOR]

The study describes the successful development of a TiO2 ceramic substrate with a protective nano-Al2O3 coating using two different coating techniques: microwave combustion and polymeric methods. The coated ceramics demonstrate enhanced corrosion resistance compared to the uncoated substrate. The optimal TiO2 substrate was prepared by firing it at 1000 °C. This was done to give the desired physical properties of the TiO2 substrate for the coating procedures. Nano-Al2O3 powder was coated onto the surface of the TiO2 substrates. The TiO2 substrates with the Al2O3 coating were then calcined (heat-treated) at 800 and 1000 °C. The structures, morphology, phase composition, apparent porosity, bulk density, and compressive strength of the substrate and coated substrate were characterized. Upon firing at 1000 °C, it was discovered that the two phases of TiO2—rutile and anatase—combine in the substrate. Once the substrate has been coated with nano Al2O3 at 1000 °C, the anatase is transferred into rutile. When compared to the substrate, the coated substrate resulted in a decrease in porosity and an increase in strength. The efficiency of the ceramic metal nanoparticles Al2O3 as a good coating material to protect the TiO2 substrates against the effect of the corrosive medium 0.5 M solution of H2SO4 was measured by two methods: potentio-dynamic polarization (PDP) and the electrochemical impedance spectroscopy (EIS). The results indicated that the corrosion rate was decreased after the substrate coated with alumina from (67.71 to 16.30 C.R. mm/year) and the percentage of the inhibition efficiency recorded a high value reaching (78.56%). The surface morphology and composition after electrochemical measurements are investigated using SEM and EDX analysis. After conducting the corrosion tests and all the characterization, the results indicated that the coated TiO2 substrate prepared by the polymeric method at 800 °C displayed the best physical, mechanical, and corrosion-resistant behavior. [ABSTRACT FROM AUTHOR]

Extensive research efforts have been focused on customizing the microstructure, macrostructure, and phase composition of calcium phosphate for enhanced biocompatibility and bioactivity in scaffolds for bone substitutes. Despite significant progress, achieving precise phase composition and microstructure remains a challenge, primarily due to the necessity of scaffold sintering. This study addresses the challenges in developing customized patient‐specific bone substitutes by proposing a sequential approach that reduces processing steps while providing control over the phase and morphology of the scaffolds’ structure. The methodology utilizes freeze‐casting and sintering for highly porous the scaffolds’ preparation, followed by hydrothermal treatment to modify the microstructure. The introduction of CaCO3 induces a phase transformation of tricalcium phosphate, increasing the hydroxyapatite content, while the overall macrostructure retains the characteristics of freeze‐casting. The surface morphology undergoes a transition from equiaxial grains to whiskers‐like structures and hexagonal rods, impacting compressive strength. Following hydrothermal treatment, the formation of whiskers‐like hydroxyapatite grains leads to a notable strength increase from 2.8 to 5.7 MPa. Remarkably, the scaffolds undergo nearly complete phase transformation, shifting from 100% tricalcium phosphate to 99% hydroxyapatite, all while conserving the macrostructure. [ABSTRACT FROM AUTHOR]

Highlights This study investigates the mechanical properties and erosion resistance of high temperature–pressure carbon‐epoxy novolac insulation reinforced with ZrB2/SiC particles. For this reason, at first, five samples were fabricated using the hot press, which included resin epoxy novolac EPN1180 base without reinforcement and four samples containing resin with 20:80, 30:70, 40:60, and 50:50 of SiC: ZrB2 particles respectively. After manufacturing of the samples, the mechanical properties were evaluated through bending and tensile testing, followed by erosion resistance properties by the use of oxyacetylene flame erosion tests. Chemical composition and surface morphology analysis of the composites were conducted using energy‐dispersive spectroscopy, scanning electron microscopy, and x‐ray diffraction analysis. Results indicate that the addition of ceramic particles enhances both mechanical properties and erosion resistance of the composite. The pure resin sample exhibited the highest weight loss and thickness reduction, while the sample containing 40% SiC and 60% ZrB2 demonstrated the least weight loss and thickness reduction about 55% and 83% respectively compared to pure sample. Additionally, the sample with 30% SiC and 70% ZrB2 had the lowest backside temperature. Furthermore, the sample with 20% SiC and 80% ZrB2 exhibited the highest mechanical properties, with a tensile strength of 422.5 MPa and flexural strength of 587.11 MPa. Morphological analysis revealed the presence of phases such as SiO2, ZrO2, and ZrSiO4 attributable to the ZrB2/SiC particles, contributing to the enhancement of erosion resistance. Examines volume ratios of ZrB2/SiC. Discovers the best particle ratio (20%SiC, 80%ZrB2) for mechanical properties. Identifies the best particle ratio (30% SiC, 70% ZrB2) for erosion resistance. Reveals key phases enhancing erosion resistance with advanced analysis methods. Linear and mass ablation rate improved by 83% and 55% (best formation). [ABSTRACT FROM AUTHOR]

Viscose-based carbon fibers (VBCFs) were chlorinated with CCl4 vapor to investigate the effect of chlorination temperature on their microwave properties. The maximum chlorine content of 2.0 mmol g−1 was obtained at 450 °C. TEM and SEM showed carbon nanostructures and surface morphology preservation, respectively. TGA and TPD MS confirmed the formation of carbon-oxygen and chlorine-carbon groups, including CCl3 groups. The prepared chlorinated VBCFs can effectively reflect X-band microwaves, with nearly constant reflection losses over a wide frequency range, and are characterized by minimum transmission losses of −22 dB. [ABSTRACT FROM AUTHOR]

The tortuous randomized pores inside porous bronze bring significant challenges to the machining technology and surface morphology evaluation. Additionally, some of the current measurement methods for morphology characterization can only reflect partial information about the porous surface. In this study, the cutting experiments with monocrystal diamond (MCD) tools were conducted on porous bronze to investigate the effects of machining parameters on surface morphology. Moreover, a series of image processing techniques were applied to batch-collected surface images. On this basis, before and after cutting experiments, the fractal dimensions and pore parameters were calculated to characterize and compare the changes in porous surface morphology. The experimental results indicated that the increase in cutting depth led to a larger fractal value while increased cutting speeds reduced the complexity of the machined surfaces. Among them, the cutting depth had the greatest influence on the material removal process, when the cutting depth exceeded 20 μm, the material removal process transitioned from the initial single plastic removal mode to the occurrence of brittle spalling. During the plastic removal model, the fractal dimension decreased by a maximum of 6.70 %. However, in the experimental group with brittle spalling, that value increased by 6.28 %. After processing experiments, the surface porosity of all samples ranged from 3.33 % to 12.8 %, showing a change of - 40 % to +52 % compared to the initial surface. Moreover, in this study, the fractal dimensions could provide a more comprehensive evaluation method for porous surface morphology through statistical analysis. The cutting experiments and surface morphology analysis are available to obtain the optimal machining parameters for achieving the relatively desired surface morphology. [Display omitted] • Ideal porous surface quality can be obtained via the sharp MCD cutting tool. • Porous surface morphology is determined by pore structure and machining parameters. • Cutting depth increase leads to removal pattern transformation of porous bronzes. • Fractal theory characterizes random pore morphology of porous bronze surfaces. [ABSTRACT FROM AUTHOR]

Constraining the escape fraction of Lyman Continuum (LyC) photons from high-redshift galaxies is crucial to understanding reionization. Recent observations have demonstrated that various characteristics of the Ly |$\, \alpha$| emission line correlate with the inferred LyC escape fraction (⁠|$f_{\rm esc}^{\rm LyC}$|⁠) of low-redshift galaxies. Using a data set of 9600 mock Ly |$\, \alpha$| spectra of star-forming galaxies at |$4.64 \le z \le 6$| from the SPHINX |$^{20}$| cosmological radiation hydrodynamical simulation, we study the physics controlling the escape of Ly |$\, \alpha$| and LyC photons. We find that our mock Ly |$\, \alpha$| observations are representative of high-redshift observations and that typical observational methods tend to overpredict the Ly |$\, \alpha$| escape fraction (⁠|$f_{\rm esc}^{\rm Ly\, \alpha }$|⁠) by as much as 2 dex. We investigate the correlations between |$f_{\rm esc}^{\rm LyC}$| and |$f_{\rm esc}^{\rm Ly\, \alpha }$|⁠ , Ly |$\, \alpha$| equivalent width (⁠|$W_{\lambda }({\rm Ly\, \alpha })$|⁠), peak separation (⁠|$v_{\rm sep}$|⁠), central escape fraction (⁠|$f_{\rm cen}$|⁠), and red peak asymmetry (⁠|$A_f^{\rm red}$|⁠). We find that |$f_{\rm esc}^{\rm Ly\, \alpha }$| and |$f_{\rm cen}$| are good diagnostics for LyC leakage, selecting for galaxies with lower neutral gas densities and less UV attenuation that have recently experienced supernova feedback. In contrast, |$W_{\lambda }({\rm Ly\, \alpha })$| and |$v_{\rm sep}$| are found to be necessary but insufficient diagnostics, while |$A_f^{\rm red}$| carries little information. Finally, we use stacks of Ly |$\, \alpha$|⁠ , H |$\, \alpha$|⁠ , and F150W mock surface brightness profiles to find that galaxies with high |$f_{\rm esc}^{\rm LyC}$| tend to have less extended Ly |$\, \alpha$| and F150W haloes but larger H |$\, \alpha$| haloes than their non-leaking counterparts. This confirms that Ly |$\, \alpha$| spectral profiles and surface brightness morphology can be used to better understand the escape of LyC photons from galaxies during the epoch of reionization. [ABSTRACT FROM AUTHOR]

Copper oxide nanoparticles calcined at temperatures varying from 500 to 900 °C were prepared through non-aqueous sol–gel route by using 2-ethyl hexanol as a modifying agent. Phase composition, presence of functional groups, thermal behavior, surface morphology and elemental composition of the prepared samples were identified by XRD, IR, TGA, FESEM and EDX. The results revealed the formation of single phase, i.e., monoclinic tenorite copper oxide with its entire transformation after calcination at 500 °C. Polyhedron shape nanoparticles of size below 100 nm were formed with a significant increase in the particle size and agglomeration due to nucleation growth of nanoparticles with the rise in calcination temperature. The synthesized samples showed a direct band gap of 4.08–4.14 eV. The study revealed that following the non-aqueous sol–gel process with 2-ethyl hexanol as a modifying agent inhibited agglomeration resulting in the formation of well-dispersed nanoparticles. [ABSTRACT FROM AUTHOR]

This paper describes the effects of incorporating the commercially available phenylurea-based antimicrobial agent S89 to pre-vulcanised natural rubber latex (NRL). The physical properties of the dipped film derived from the S89 incorporated into pre-vulcanised NRL such as antimicrobial efficacy, wettability properties, surface characteristics, surface morphology and tensile strength were further evaluated. The antibacterial activity of S89 in NRL films was tested using the agar disc diffusion method and S89 had been demonstrated to suppress and prevent bacterial growth even at low loading levels. Moreover, the minimum inhibitory concentration (MIC) of S89 was obtained by fitting the inhibition zone diameter and loading of S89 using two mathematical diffusion models, free and dissipative models. In this work, the dissipative model is shown to be the best-described diffusion model for S89. The leaching behaviour of S89 in an artificial sweat was investigated where the leachate of S89 is observed after 20 min of immersion at a very low concentration (0.039 ug/mL). Interestingly, NRL films incorporated with S89 displayed better wettability properties on air facing (AF) surface indicating that the AF surface of the film had been altered to be more hydrophilic. Nonetheless, there were no changes observed to the former facing (FF) surface. In addition, the polarity of the surface was also reduced which corresponds to the contact angle results. Further analysis of the Field Emission Scanning Electron Microscopy (FESEM) surface morphology on the NRL film incorporated with S89 exhibited sufficient miscibility and homogeneity during latex compounding with no agglomeration observed on both surfaces (air and former) and at the cross-sectional surface. Meanwhile, comparative tensile strength (of more than 20Mpa) of NRL films incorporated with S89 was observed for low dosage at 1 phr and 3 phr. In conclusion, antimicrobial natural rubber (NR) films for glove application with satisfactory tensile properties, adequate wettability properties, non-agglomerated surface morphology and good antimicrobial properties were achieved by employing a low loading of S89 in the NRL. [ABSTRACT FROM AUTHOR]