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Appropriate protection and guiding are crucial during peripheral nerves repair. New generation nerve guidance conduits (NGCs) should not only provide mechanical support for the damaged nerve but also support healing processes. One of the most promising tissue regeneration applications is fibrous biomaterials since they are characterized by high porosity, flexibility, and strength. Additionally, they enable cell adhesion and proliferation. In this study, novel fibrous nanocomposites were obtained by applying the electrospinning technique, using polylactic acid (PLA) as a polymeric matrix which was further modified with metallic nanoparticles coated with conductive polymers. Such an approach resulted in the obtainment of biomaterials with a potential ability to conduct nerve impulses. The chemical structure of the obtained composites, as well as the morphology of ready products and separate nanocomponents, were investigated using Fourier-transform infrared spectroscopy (FTIR), transmission electron microscope (TEM) and scanning electron microscope (SEM) techniques. Furthermore, conductive and swelling properties in various media were determined. Finally, biomaterials were confirmed to be non-cytotoxic to L929 mouse fibroblasts and 1321N1 human glial cells. Based on the presented results, it can be concluded that nanofibrous nerve guidance conduits have all the key properties in the process of peripheral nerve regeneration and may constitute an important step in novel NGCs development. [ABSTRACT FROM AUTHOR]

Biodegradable poly(butylene succinate‐co‐adipate)/Poly(3‐hydroxybutyrate‐co‐3‐hydoxyvalerate) (PBSA/PHBV) filled with lignocellulosic sidestream/fibers from cowpea, a neglected and underutilized African crop are produced by injection molding and extrusion film casting. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) suggests that the fibers have more affinity and interfacial interaction with PBSA than PHBV. This is shown by a decrease in dampening of PBSA and an increase in dampening of PHBV with fiber addition. In addition, fiber addition results in more homogeneous crystal morphology of PBSA, while resulting in more heterogeneous crystal morphology of PHBV. The tensile strength of injection molded bio‐composites increases with fiber addition due to good interfacial adhesion between the matrix and fibers revealed by scanning electron microscope. In contrast, the tensile strength of bio‐composite films decreases with fiber addition due to the high‐volume fraction of pores in bio‐composite films that act as stress raisers. The stiffness of both injection molded, and bio‐composite films increase with fiber addition, as revealed by an increase in Young's modulus and storage modulus, while the tensile strain decreases. In conclusion, low‐value cowpea sidestream can be used as a filler to produce injection molded bio‐composites and bio‐composite films for potential application as rigid and flexible packaging. [ABSTRACT FROM AUTHOR]

The study aimed to develop and analyze bio-based composites, incorporating moringa bioresin and hemp fibers as reinforcing elements. The composites were fabricated using four weight percentage combinations of epoxy, moringa bioresin, and hemp fiber. The fabricated composites were characterized by their mechanical, thermal, water absorption, biodegradability, and morphological properties. The study revealed that the composite with the highest proportion of moringa bioresin (30 wt. %) exhibited better mechanical properties. Moreover, the flexural strength and Shore D hardness were impacted by both the matrix and reinforcing materials' weight percentages. Thermal analysis showed that the composites had good thermal stability, while water absorption analysis indicated that the composites had good water resistance. Biodegradability analysis showed that the composites had a high rate of biodegradation, making them environmentally friendly. The distribution of reinforcing fibers within the matrix material was found to be uniform through the use of scanning electron microscope based morphological analysis. The results indicate that moringa bioresin and hemp fiber composites have the potential to be used as sustainable alternatives to petroleum-based composites in various applications. [ABSTRACT FROM AUTHOR]

It has recently been demonstrated that electron beam injection into p-type β-gallium oxide leads to a significant linear increase in minority carrier diffusion length with injection duration, followed by its saturation. The effect was ascribed to trapping of non-equilibrium electrons (generated by a primary electron beam) at meta-stable native defect levels in the material, which in turn blocks recombination through these levels. In this work, in contrast to previous studies, the effect of electron injection in p-type Ga2O3 was investigated using cathodoluminescence technique in situ in scanning electron microscope, thus providing insight into minority carrier lifetime behavior under electron beam irradiation. The activation energy of ∼0.3 eV, obtained for the phenomenon of interest, is consistent with the involvement of Ga vacancy-related defects. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sc3+ is selected to replace V3+ and PAN is introduced to provide porous carbon substrate. • Sc bonds with oxygen to form ScO 6 , resulting in improved structural stability and kinetics. • PAN can induce a beneficial nitrogen-doped carbon skeleton with defects, resulting in enhanced electronic conductivity. • After cycling XRD/SEM confirms the stabilized porous carbon skeleton and improved crystal stability. • Ex-situ XRD analysis reveals the crystal volume change in Sc-3 is relatively slight but reversible. The poor structural stability and conductivity of Na 3 V 2 (PO 4) 3 (NVP) have been serious limitations to its development. In this paper, Sc3+ is selected to replace partial site of V3+ which can enhance its ability to bond with oxygen, forming the ScO 6 octahedral unit, resulting in improved structural stability and better kinetic properties for the NVP system. Moreover, due to the larger ionic radius of Sc3+ compared to V3+, moderate Sc3+ substitution can support the crystal framework as pillar ions and expand the migration channels for de-intercalation of Na+, thus efficiently promoting ionic conductivity. The introduction of polyacrylonitrile (PAN) to provide an N -doped porous carbon substrate is another key aspect. The low-cost carbon resource of PAN can induce a beneficial nitrogen-doped carbon skeleton with defects, enhancing electronic conductivity at the interface to reduce the polarization phenomenon. The established pore structure can serve as a buffer for unit cell deformation caused by Na+ migration. Furthermore, the enlarged specific surface area provides more active sites for electrolyte infiltration, improving the material utilization rate. The after cycling X-ray Diffraction/scanning electron microscope (XRD/SEM) further confirms the stabilized porous carbon skeleton and improved crystal stability of Sc-3 material. Ex-situ XRD analysis shows that the crystal volume change in the Sc-3 cathode is relatively slight but reversible during the charge/discharge process, indicating that Sc3+ doping plays a crucial role in stabilizing the unit cell structure. The hybrid Sc/VO 6 and PO 4 units jointly build a strong bone structure to resist stress and weaken deformation. Accordingly, the optimized Sc-3 sample reveals an initial capacity of 115.9 mAh/g at 0.1C, with a capacity retention of 78.6 % after 2000 cycles at 30C. The Sc-3//CHC full battery can release a capacity of 191.3 mAh/g at 0.05C, accompanied by successful illumination, showcasing its promising practical applications. [ABSTRACT FROM AUTHOR]

Samples returned from the carbonaceous asteroid (162173) Ryugu by the Hayabusa2 mission revealed that Ryugu is composed of materials consistent with CI chondrites and some types of space weathering. We report detailed mineralogy of the fine‐grained Ryugu samples allocated to our "Sand" team and report additional space weathering features found on the grains. The dominant mineralogy is composed of a fine‐grained mixture of Mg‐rich saponite and serpentine, magnetite, pyrrhotite, pentlandite, dolomite, and Fe‐bearing magnesite. These grains have mineralogy comparable to that of CI chondrites, showing severe aqueous alteration but lacking ferrihydrite and sulfate. These results are similar to previous works on large Ryugu grains. In addition to the major minerals, we also find many minerals that are rare or have not been reported among CI chondrites. Accessory minerals identified are hydroxyapatite, Mg‐Na phosphate, olivine, low‐Ca pyroxene, Mg‐Al spinel, chromite, manganochromite, eskolaite, ilmenite, cubanite, polydymite, transjordanite, schreibersite, calcite, moissanite, and poorly crystalline phyllosilicate. We also show scanning transmission electron microscope and scanning electron microscope compositional maps and images of some space‐weathered grains and severely heated and melted grains. Although our mineralogical results are consistent with that of millimeter‐sized grains, the fine‐grained fraction is best suited to investigate impact‐induced space weathering. [ABSTRACT FROM AUTHOR]

Preparation procedures of polished sections of the Ryugu samples returned by the Hayabusa2 spacecraft were established through tests using CI and CM chondrites as analog materials of the Ryugu samples and processing of the Ryugu samples. The procedures consisted of four steps: epoxy‐coating, embedding in epoxy cylinders, cutting with a wire saw, and dry polish by hand. There are three key points for successful preparation of the polished sections: (1) ethanol‐mixed epoxy with low viscosity for reinforcing the fragile samples, (2) handling under dry conditions to avoid breakup of the samples on contact with liquids due to their highly porous nature, and (3) X‐ray computed tomography data for exposing maximum surface areas of target mineral phases and clasts. These key points may also be important for processing of samples returned from asteroid Bennu and the Martian Moon Phobos, as those samples are likely to be hydrous carbonaceous chondrite‐like materials. The established procedures induce two side effects: zoning of the polished surface of the Ryugu samples in scanning electron microscope images reflecting differences in carbon contents due to permeation of low viscosity epoxy resin into the sample surface and fractures in anhydrous minerals possibly due to shear stress during dry polishing. [ABSTRACT FROM AUTHOR]

Nanomaterials based on metal oxides, especially Cu2O, have received much attention in recent years due to the many unique properties of the surface plasmon resonance they provide. The report presented the co‐precipitation method, a simple preparation method to produce Cu2O oxide particles. In addition, to improve the unique antibacterial properties of Cu2O, a proposed method is to attach Ag nanoparticles to the surface of Cu2O particles. The Cu2O and Cu2O−Ag particles were synthesized based on redox reactions using ascorbic acid (LAA) as a reducing agent. Moreover, in this experiment, two surfactants, polyethylene glycol 6000 (PEG 6000) and sodium dodecyl sulfate (SDS), were added during the manufacturing process to create particle samples and particle combinations with better properties than the original sample. Changes in the characteristics and properties of particle samples are determined by many different physical and chemical methods such as ultraviolet‐visible spectroscopy (UV‐Vis), infrared spectroscopy (IR), noise X‐ray radiation (XRD), scanning electron microscope (SEM), dynamic light scattering (DLS), energy dispersive X‐ray spectroscopy (EDS), and transmission electron microscopy (TEM). Finally, the activity against bacteria, including E. coli and S. aureus, was also tested using the agar well diffusion method to determine the zone of inhibition. The results improved the particle size value, which decreased by half to 200 nm when two additional surfactants, PEG and SDS, were added. In addition, the antibacterial ability has also been shown to increase significantly when the diameter of the bacterial inhibition zone increased significantly, reaching values of 20 mm (Cu2O/Ag/SDS) and 32 mm (Cu2O/Ag/PEG) for the E. coli bacterial strain. The initial test sample was only about 14 mm in size. The S. aureus bacterial strain also had a similar improvement trend after adding Ag to the Cu2O surface with the appearance of two surfactants, SDS and PEG. The inhibition zone diameter values reached the optimal value at 36 mm in the Cu2O/Ag/PEG particle combination sample compared to only the initial 26 mm in the Cu2O particle sample. Finally, the particle samples are added to the acrylic emulsion paint film to evaluate the changes. Positive results were obtained, such as improvement in adhesion (1.22 MPa), relative hardness (240/425), and sand drop resistance (100 L/mil) in the Cu2O/Ag/PEG particle combination sample, which showed the correctness and accuracy of the research. [ABSTRACT FROM AUTHOR]

The influence of the surface sample potential on the head-incident electron beam in the scanning electron microscope has been studied in terms of the mirror effect. The multipole and charged disc models have been used to approximate the sample potential. The energy conservation law is used to assist set up the equation of motion for the incident electron. The point of reflection of the electrons along the length between the sample surface and the column diaphragm is then determined by solving the equation. In fact, the beam and surface potential characteristics mostly determine the reflection point's value. In light of the variations between the two models that were utilized, the reflection behavior was examined in terms of these characteristics. The outcomes have demonstrated that, when it comes to simulating the surface potential, each model has both advantages and disadvantages. In reality, the two models exhibit comparable results over a broad range of distances between the sample surface and the column diaphragm when the common parameters are placed in parallel. However, the variance between them occurs in a very short distance that almost does not exceed 13% approximately. Nevertheless, because of its own mathematical nature, the multipole model is best appropriate to estimate the surface potential of highly concentrated trapped charges. Meanwhile, the charged disc model is suitable for approximating the surface potential for low concentrated trapped charges. [ABSTRACT FROM AUTHOR]

This paper details the utilization of the focused ion beam digital image correlation (FIB-DIC) technique for measuring in-plane displacements and the employment of the height digital image correlation (hDIC) technique as a two-step DIC method for determining displacements without an out-of-plane component within the region of interest. Consideration is given to the microscopy data's measurement scale and resolution to confirm the capability of both techniques to conduct micro-scale correlations with nano-scale sensitivity, making them suitable for investigating the residual elastic strains formed due to processing. The sequential correlation procedure of the FIB-DIC technique has been optimized to balance accuracy and performance for correlating sequential scanning electron microscope (SEM) images. Conversely, the hDIC technique prioritizes the accurate correlation of SEM images directly with the reference state without a sequential procedure, offering optimal computational performance through advanced parallel computing tools, particularly suited for correlating profilometry data related to large-scale displacements. In this study, the algorithm of the hDIC technique is applied as a two-step DIC to evaluate the elastic strain relaxation on the surface of a ring core drilled using a focused ion beam. Both techniques are utilized to correlate the same SEM images collected during the monitoring of the ring drilling process. A comparison of the correlation results of both techniques is undertaken to quantify the near-surface residual elastic strains, with an analysis conducted to discern the accuracy of the hDIC algorithm. Furthermore, the distinctions between the two techniques are delineated and discussed. [ABSTRACT FROM AUTHOR]

The effects of ball milling on the physicochemical, functional, and emulsification characteristics of Polygonatum sibiricum insoluble dietary fiber (PIDF) were investigated. Through controlling milling time (4, 5, 6, 7, and 8 h), five PIDFs (PIDF-1, PIDF-2, PIDF-3, PIDF-4, and PIDF-5) were obtained. The results showed that ball milling effectively decreased the particle size and increased the zeta-potential of PIDF. Scanning electron microscope results revealed that PIDF-5 has a coarser microstructure. All PIDF samples had similar FTIR and XRD spectra. The functional properties of PIDF were all improved to varying degrees after ball milling. PIDF-3 had the highest water-holding capacity (5.12 g/g), oil-holding capacity (2.83 g/g), water-swelling capacity (3.83 mL/g), total phenol (8.12 mg/g), and total flavonoid (1.91 mg/g). PIDF-4 had the highest ion exchange capacity. Fat and glucose adsorption capacity were enhanced with ball milling time prolongation. PIDF-5 exhibited a contact angle of 88.7° and lower dynamic interfacial tension. Rheological results showed that PIDF-based emulsions had shear thinning and gel-like properties. PE-PIDF-5 emulsion had the smallest particle size and the highest zeta-potential value. PE-PIDF-5 was stable at pH 7 and high temperature. The findings of this study are of great significance to guide the utilization of the by-products of Polygonatum sibiricum. [ABSTRACT FROM AUTHOR]

Microscale laser dynamic forming, as a novel high-speed microforming technique, can overcome the shortcomings of traditional microforming methods. However, in practical applications, laser dynamic microforming technology is often affected by the rebound behavior of the workpiece, limiting the further improvement of processing quality and efficiency. This paper aims to reduce the rebound effect in laser dynamic forming by using multi-pulse laser shock loading. The forming results of workpieces under different laser energies and laser impact numbers were studied using experimental and numerical simulation methods. After multiple laser shocks, numerical simulations of the forming results were conducted using ANSYS/LS-DYNA software. These numerical simulation results were then experimentally validated and compared. The surface morphology of the workpieces was characterized using a confocal microscope and a scanning electron microscope (SEM). Energy-dispersive spectroscopy (EDS) was used to analyze the chemical element content changes in the collision regions at the bottoms of the workpieces after multi-pulse loading. The SEM and EDS results revealed the collision behavior patterns during the forming process. Finally, the forming laws of workpieces under multiple laser shocks were summarized. [ABSTRACT FROM AUTHOR]

The effect of Al or Cu content on the microstructure and mechanical properties of continuous casting and extrusion Zn alloys has been studied by a room temperature tensile test, X-ray diffraction, and scanning electron microscope. With the increase in Al content, the microstructure of continuous casting and extrusion Zn alloys slightly coarsens, and the lamellar eutectic structure increases. The changes in the above structural factors result in a slight decrease in strength and a significant increase in the elongation of Zn-Al alloys. The strength of Zn alloys increases as the Cu content increases due to the increased content and size of the second phase in the Zn alloys. This means that the mechanical properties of Zn alloys can be adjusted by a continuous casting and extrusion process, and the improvement of equipment capacity can improve the structure and morphology of the alloys. [ABSTRACT FROM AUTHOR]

Novel research has been conducted to characterize fiberboards made from palm frond fibers and polyester resin. In this study, polyester resin served as the matrix, and palm frond fibers with a size of 80 mesh were employed as the filler. The fiberboard composites were produced using a hot press at 70°C for 20 minutes, with varying mass compositions of polyester resin to palm frond fibers: S1 (60%:40%), S2 (65%:35%), S3 (70%:30%), S4 (75%:25%), and S5 (80%:20%). Parameters observed include physical properties (density and porosity), mechanical properties (impact, tensile, and flexural strength), and microstructure analysis using scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The results indicate that S5 exhibits optimal properties, including a density value of 1.197 g/mL, low porosity at 0.232%, and mechanical characteristics with an impact strength of 271.251 J/m2, tensile strength of 23.221 MPa, and flexural strength of 149.837 MPa. However, according to the DSC data, S1 stands out with a higher temperature water evaporating point at 82.48°C, indicating greater thermal stability. In addition, SEM results for the S5 sample reveal minimal voids, enhancing the fiberboard composites' physical and mechanical properties and demonstrating high stability. This fiberboard can be classified as a High-Density Fiberboard (HDF) according to JIS A 5905:2003. It is a viable alternative for household furniture, offering a substitute for traditional wood. [ABSTRACT FROM AUTHOR]

The perovskite-structured materials P b 0.75 B a 0.25 1 − x C a x (Z r 0.7 T i 0.3) O 3 for x = 1 and 2 at.% were synthesized using the conventional mixed-oxide method and carbonates. Microstructural analysis, performed using a scanning electron microscope, revealed rounded grains with relatively inhomogeneous sizes and distinct grain boundaries. X-ray diffraction confirmed that the materials exhibit a rhombohedral structure with an R3c space group at room temperature. Piezoelectric resonance measurements were conducted to determine the piezoelectric and elastic properties of the samples. The results indicated that a small amount of calcium doping significantly enhanced the piezoelectric coefficient d31. The calcium-doped ceramics exhibited higher electrical permittivity across the entire temperature range compared to the pure material, as well as a significant value of remanent polarization. These findings indicate that the performance parameters of the base material have been significantly improved, making these ceramics promising candidates for various applications. [ABSTRACT FROM AUTHOR]

The combination of multiplex polymerase chain reaction (mPCR) and microfluidic technologies demonstrates great significance in biomedical applications. However, current microfluidics-based molecular diagnostics face challenges in multi-target detection due to their limited fluorescence channels, complicated fabrication process, and high cost. In this research, we proposed a cost-effective sandblasting method for manufacturing silicon microchips and a chip-based microdevice for field mPCR detection. The atomic force microscopy (AFM) images showed a rough surface of the sandblasted microchips, leading to poor biocompatibility. To relieve the inhibitory effect, we dip-coated a layer of bovine serum albumin (BSA) on the irregular substrate. The optimized coating condition was determined by scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS) (65 °C for 60 min). After sufficient coating, we performed on-chip PCR tests with 500 copies/mL Coronavirus Disease 2019 (COVID-19) standard sample within 20 min, and the sandblasted microchip displayed a higher amplification rate compared to dry etching chips. Finally, we achieved a 50 min mPCR for screening five resistance genes of the endophthalmitis pathogens on our microdevices, with strong specificity and reliability. Thus, this sandblasted microchip-based platform not only provides a rapid, accessible, and effective solution for multiplex molecular detection but also enables large-scale microfabrication in a low-cost and convenient way. [ABSTRACT FROM AUTHOR]

Calcium strontium phosphate was electro-crystallized on Ti along with hydroxyapatite (HA). Stock solutions of 167 mM CaCl2, 167 mM SrCl2, and 100 mM NH4H2PO4 were initially prepared. Two different electrolyte formulations of equi-amounts of (CaCl2 + SrCl2) and NH4H2PO4 were used. The Ca:Sr ratios were maintained as 9:1 and 3:1, respectively, in these two formulations. Using these solutions, a cathodic deposit was obtained on Ti using ultrasonic agitation of the electrolyte at the current density of 10 mA/cm2 for 60 min. The electrolytes were heated at 50°C. X-ray diffraction (XRD) and field-emission scanning electron microscope (FE-SEM) analysis were utilized to characterize the phase compositions and surface morphology of the coatings. A surface roughness tester, an universal testing machine, and contact angle measurements were used to estimate the coating roughness, pull-off tensile adhesion strength, and wettability, respectively. The coatings were composed of hydroxyapatite (HA) and calcium strontium phosphate. The strontium (Sr) substitution was nearly 0.5% and 1% in the coatings obtained from the 9:1 and 3:1 Ca:Sr ratios, respectively. The coatings contained predominantly spherical crystals and occasional plate-like crystals attached to the substrate. Both the coatings displayed a similar surface roughness of about 450 nm. The coating obtained from the first electrolyte (Ca:Sr = 9:1) had a higher contact angle in simulated body fluid, but a lower pull-off adhesion strength than the coating obtained from the second (Ca:Sr = 3:1) electrolyte. [ABSTRACT FROM AUTHOR]

The Guinier–Preston (GP) zones have an important influence on the improvement of the age-hardening level of alloy. We here prepare six kinds of Mg-6Zn-5Al (ZA65) magnesium alloy samples to investigate the microstructural evolution, precipitation behavior, and strengthening mechanism using an optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM), and micro-hardness tests. The finding reveals that the GP zones are observed in non-dendritic alloys experiencing pre-aging at 80°C for 24 h, whose formation creates more nucleation sites and accelerate kinetics for precipitated phases. Consequently, the introduced pre-aging has been successful in promoting the increase of the age-hardening level of non-dendritic alloys. The double-aged non-dendritic alloys show a significantly changed microstructure with a high density of long rod-shaped β1′ precipitations, making the age-hardening level of double-aging much better than that of single-aging, and the peak value 90 HV was obtained 4 h in advance, which is an increase of 4 HV compared with that of the direct aged non-dendritic alloy. The strengthening mechanism of non-dendritic alloys is mainly summarized as grain boundary strengthening, GP zone strengthening, and the shearing strengthening of β1′ and β2′ precipitations. Among these, the GP zone strengthening is a fundamental contributor to improving the age-hardening level. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work investigated the impact of chicken egg size, including surface area and initial weight, on the effectiveness of cassava starch-based gel coating during storage at room temperature. The quality of a total of 540 fresh eggs in four different sizes (S, M, L and XL) was evaluated over a 4-week storage period at 25 ± 1 °C (60–65% RH). In this research, images from a scanning electron microscope revealed that the coatings maintained their integrity across all egg sizes, effectively covering pores and cracks throughout storage. The application of gel coating reduced weight loss and preserved the Haugh unit and yolk index, extending freshness by 1–2 weeks compared with uncoated eggs at 25 °C. The results indicated that the performance of the coating varied with egg size. Statistical analysis revealed that the surface area and initial weight of the egg significantly impacted the effectiveness of the coating in preserving quality (p < 0.001). Eggs with larger surface areas exhibited a reduced protective effect of the coating, resulting in higher weight loss and lower retention of Haugh unit and yolk index compared with the coated eggs with smaller surface areas. The coating application was more effective in preserving the Haugh unit of eggs with higher initial weights. Overall, the surface area and the initial weight of the egg should be considered as key factors to ensure optimal coating performance. [ABSTRACT FROM AUTHOR]

Introduction: Coronavirus (CoV) has become a public health crisis that causes numerous illnesses in humans and certain animals. Studies have identified the small, lipid-bound structures called extracellular vesicles (EVs) as the mechanism through which viruses can enter host cells, spread, and evade the host's immune defenses. EVs are able to package and carry numerous viral compounds, including proteins, genetic substances, lipids, and receptor proteins. We proposed that the coronavirus could alter EV production and content, as well as influence EV biogenesis and composition in host cells. Methods: In the current research, Crandell-Rees feline kidney (CRFK) cells were infected with feline coronavirus (FCoV) in an exosome-free media at a multiplicity of infection (MOI) of 2,500 infectious units (IFU) at 48 h and 72 h time points. Cell viability was analyzed and found to be significantly decreased by 9% (48 h) and 15% (72 h) due to FCoV infection. EVs were isolated by ultracentrifugation, and the surface morphology of isolated EVs was analyzed via Scanning Electron Microscope (SEM). Results: NanoSight particle tracking analysis (NTA) confirmed that the mean particle sizes of control EVs were 131.9 nm and 126.6 nm, while FCoV infectedderived EVs were 143.4 nm and 120.9 nm at 48 and 72 h, respectively. Total DNA, RNA, and protein levels were determined in isolated EVs at both incubation time points; however, total protein was significantly increased at 48 h. Expression of specific protein markers such as TMPRSS2, ACE2, Alix, TSG101, CDs (29, 47, 63), TLRs (3, 6, 7), TNF-α, and others were altered in infection-derived EVs when compared to control-derived EVs after FCoV infection. Discussion: Our findings suggested that FCoV infection could alter the EV production and composition in host cells, which affects the infection progression and disease evolution. One purpose of studying EVs in various animal coronaviruses that are in close contact with humans is to provide significant information about disease development, transmission, and adaptation. Hence, this study suggests that EVs could provide diagnostic and therapeutic applications in animal CoVs, and such understanding could provide information to prevent future coronavirus outbreaks. [ABSTRACT FROM AUTHOR]

In present research the fracture behavior of carbon fabric‐epoxy composites (CE composites) was evaluated with the addition of 0.1, 0.2, 0.5, and 0.75 weight percentages of carbon nano tubes (CNTs) at different temperatures. The CE composites with different wt.% of CNT were fabricated using land layup method and cured by hot pressing. The fracture toughness of fabricated composites was evaluated in mode–I condition at different temperature. From the results it was shown that the highest fracture toughness was observed at 0.75 wt.% of reinforcement of CNT functional fillers. The fracture toughness of 0.75 wt.% CNT filled CE composites was increased by 19.73% compared to unfilled CE composites. The fracture toughness of CNT filled CE composites diminishes with increase in temperature and the composite filled with 0.75 wt.% CNT exhibits better fracture toughness than the unfilled CE composite at all the temperatures. The fracture toughness was improved by 57.76% and 71.65% at 40 and 60°C, respectively, at 0.75 wt.% reinforcement of CNT fillers. The fractured surfaces of composites were analyzed using Scanning Electron Microscope (SEM) to study the filler contribution to enhance the fracture toughness and failure mechanism of composites. [ABSTRACT FROM AUTHOR]

Pore structure heterogeneity affects the porosity and permeability variation of tight sandstone, thereby restricting sandstone gas production. In total, 11 sandstone samples were taken as a target in the northwest margin of the Junggar Basin. Then, scanning electron microscope and high-pressure mercury injection tests are used to study the distribution of a pore and fracture system in the target sandstone. On this basis, single and multifractal models are used to quantitatively characterize the heterogeneity of pore structure, and the applicability of the classification model in characterizing the heterogeneity of the pore-fracture structure is explored. The results are as follows. (1) The target samples are divided into two types, with the mercury removal efficiency of type A samples ranging from 44.6 to 51.8%, pore size mainly distributed between 100 and 1000 nm, and pore volume percentage ranging from 43 to 69%. The mercury removal efficiency of type B samples ranges from 14 to 28%, and pore diameter distribution is relatively uniform. (2) Different fractal models represent different physical meanings. The calculation results of sponge and thermodynamic fractal models indicate that the heterogeneity of pore structure distribution in the type B sample is significantly stronger than that in type A, which is inconsistent with the conclusions of the Sierpinski model. This is because the aforementioned two models characterize the complexity of pore surface area, while the Sierpinski model characterizes the roughness of pore volume. The comparison shows that there is a significant correlation between the thermal dimensionality value DT and the volume percentage of macropores and mesopores. Therefore, the thermodynamic model can better quantitatively characterize the heterogeneity of macropore and mesoporous pore distribution. (3) The results indicate that higher pore volume range is mainly influenced by mesopores and macropores. From the relationship curve between mercury removal efficiency and single fractal dimension, it can be seen that mercury removal efficiency is greatly affected by distribution heterogeneity of the lower value area of pore volume, and it has no obvious relationship with distribution heterogeneity in the lower value area of the pore volume. [ABSTRACT FROM AUTHOR]

The paper mainly studies the effect of surface carbon content on the deformation of M50 steel bearing ring, and the carbon content is changed by short-time carburizing on the surface of the bearing ring. By using the scanning electron microscope, x-ray diffraction analyzer, hardness tester and torsion spring tester to observe the microstructure and measure the hardness and size variation characteristic. The size and ovality variations of carburized and uncarburized samples are analyzed. Results show that austempering hardness decreases and tempering hardness increases with the increase of surface carbon content. The size of the bearing ring without carburizing is reduced by 0.31 mm after austempering, and the martensite in the surface layer plays a key role in inhibiting the size reduction. The size of the bearing ring with the carbon potential of 0.6% is reduced by 0.01 mm after austempering, and the size reduction is inhibited by the transformation of martensite in the core and surface. The ununiformity of carburizing layer makes the martensitic transition time in different regions inconsistent, resulting in the ovality of M50 steel increased by 0.14 mm. [ABSTRACT FROM AUTHOR]

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In order to improve the wear and corrosion resistance and enhance the tribological and mechanical properties of gray cast iron, the laser surface cladding technique was employed to fabricate double-layer coatings with different Ni/WC ratios on the surface of gray cast iron. The effects of laser processing parameters and the type of Ni-based alloy on the microstructure and properties of the gray cast iron matrix and laser-clad layer were investigated. A 316L stainless steel transition layer was introduced between the gray cast iron substrate and the Ni/WC coating to prevent the cladding layer from cracking. The tribological and mechanical properties of the laser-clad coatings were characterized with various tests at the macro- and micro-scales; the residual stresses on the coating surfaces were measured, and electrochemical tests were also carried out. The microstructures of the clad layers were analyzed by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results show that the laser-clad layers exhibit excellent vibration and noise reduction performance, which is partially due to the reduction and stabilization of the coefficients of friction (COFs) and the high levels of compressive residual stress on the surface of the laser-clad layers. The wear and corrosion resistance of the laser-clad layers are significantly improved, and the maximum wear loss of the laser-clad coating was about only 5% of that of the unclad gray cast iron substrate. This research has significance for the laser surface modification of cast iron, steel, and other metals, which is an increasingly important topic, especially in the automotive friction brake industry. [ABSTRACT FROM AUTHOR]

Reactive powder concrete (RPC) is widely used in large-scale bridges, and its durability in coastal areas has become a significant concern. Straw fibers have been evidenced to improve the mechanical properties of concrete, while research on their influence on the chloride corrosion resistance of RPC is deficient. Therefore, it is essential to establish the relationships between the quantities and parameters of straw fibers and the properties of the resulting concrete. In this study, the mass loss rates (MLRs), the relative dynamic modulus of elasticity (RDME), the electrical resistance (R), the AC impedance spectrum (ACIS), and the corrosion rates of steel-bar-reinforced RPC mixed with 0%–4% straw fibers by volume of RPC were investigated. A scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to analyze the corrosion of steel bars. The reinforced RPC specimens were exposed to a 3% NaCl dry-wet alternations (D-As) and 3% NaCl freeze-thaw cycles (F-Cs) environment. The results show that, after adding 1%–4% straw fibers, the setting time and slump flow of fresh RPC were reduced by up to 16.92% and 12.89%. The MLRs were −0.44%–0.43% and −0.38%–0.42%, respectively, during the D-As and F-Cs. The relationship between the RDME and the fiber volume ratio was the quadratic function, and it was improved by 9.34%–13.94% and 3.01%–5.26% after 10 D-As and 100 F-Cs, respectively. Incorporating 4% straw fibers reduced the R values of the reinforced RPC specimens by up to 22.90% and decreased the corrosion rates after 10 D-As and 100 F-Cs by 26.08% and 82.29%, respectively. The impedance value was also increased. Moreover, a dense, ultra-fine iron layer and α-FeO(OH) were observed in the rust of rebars by SEM and XRD, as the corrosion resistance of rebars was enhanced. The results indicate that straw fibers improved the corrosion resistance of RPC, which can serve as a protective material to inhibit concrete cracking and thereby prevent rebar oxidation. This study provides theoretical support for the investigation of surface phenomena in reinforced RPC with straw fibers. [ABSTRACT FROM AUTHOR]

This research article aims to improve the specific capacitance of DC-etched Al foil for Al electrolytic capacitors by forming an Al2O3-TiO2 composite anodic oxide film. DC-etched Al foils for aluminum electrolytic capacitors were immersed in a TiO2 precursor sol, followed by calcination and anodizing to manufacture a TiO2-Al2O3 composite anodic oxide film. TiO2 precursor sol–gel particles after calcination were analyzed by XRD. During anodization, the anode potential with time was measured by a digital meter. A scanning electron microscope, electrochemical impedance measurements, and a general digital LCR meter were adopted to explore the microstructure and property of the anodic oxide films. The specific capacitance for the TiO2-Al2O3 composite anodic oxide film and a pure Al anodic one is 3.013 μF/cm2 and 2.435 μF/cm2 at C60V, respectively. The thickness is 87.26 nm for the former and 177.65 nm for the latter. The results show that the TiO2-Al2O3 composite anodic oxide film is about 51% thinner than the single Al anodic film, accounting for a large improvement in specific capacitance. The formation efficiency of the pretreated sample is much higher than that of the blank sample, owing to the pre-deposited TiO2 layer and thermal Al oxide layer. However, the composite anodic oxide film's specific resistance was reduced and its dielectric loss was also aggravated, resulting from the doping-introduced structural defects. [ABSTRACT FROM AUTHOR]

Current chemotherapeutic treatments have severely limited effectiveness against tumors. Co-delivery of chemotherapeutic drugs and small interfering RNA (siRNA) in a nanoliposomal drug delivery system is known to selectively improve cytotoxicity against tumors. The current study aimed to achieve augmented combination therapy (Dasatinib-DST and siRNA targeting COL11A1 gene) against lung adenocarcinoma (LUAD) in vitro. The microbubble liposome (MB-LP)-based codelivery system (DST and COL11A1) used in this study was prepared using the thin film hydration method. The resulting codelivery system (MB-LP/DST/siRNA) average size and zeta potential were about 1611.5 nm and − 10.35 mV, respectively. Nevertheless, the average size of the MB-LP drug delivery system alone was 530 nm. The percentage encapsulation efficiency (% EE) of the combination drug (DST and COL11A1siRNA) in the MB-LP nanodelivery system was 62.9%. The surface morphology of the codelivery system (MB-LP/DST/siRNA) was analysed using a High-Resolution Scanning Electron Microscope (HR-SEM) and a High-Resolution Transmission Electron Microscopy (HR-TEM). Both confirmed the spherical shape of the MB-LP system. MTT-based proliferation analysis in vitro revealed that DST and COL11A1siRNA containing MB-LP codelivery system caused significant inhibition of cell proliferation against LUAD. This is the first study that suggests the co-delivery of the chemotherapeutic drug (DST) and COL11A1siRNA using the MB-LP drug delivery system facilitates an anti-proliferative effect against LUAD cells. Additionally, we also conclude that these prospective results strengthen the evidence on the potential of combination therapy (DST and COL11A1siRNA) against LUAD. [ABSTRACT FROM AUTHOR]

This study investigated the susceptible sites for pit nucleation in a transformation-induced plasticity (TRIP) Fe39Mn20Co20Cr15Si5Al1 (at.%) high-entropy alloy (HEA) in 3.5 wt.% NaCl solution. The investigation involved a constant-load stress corrosion cracking (SCC) experiment. The SCC testing was interrupted at different pre-determined time intervals to characterize the specimen surface using a scanning electron microscope (SEM), electron backscattered diffraction (EBSD), and a three-dimensional optical stereomicroscope. The EBSD results revealed pit nucleation at the susceptible γ–ε interphase and ε–ε interlath/plate boundaries. The three-dimensional profile and SEM results indicated an increase in pit depth with no change in pit diameter on the surface of the specimen as the experiment progressed over time. This study highlights the importance of microstructural features and mechanical loading in the corrosion behavior of TRIP HEAs, providing insights into the mechanisms of pit nucleation and growth under aggressive environmental conditions. [ABSTRACT FROM AUTHOR]

The study analyzed surface treatment's impact on mechanical properties of Fe-based amorphous coatings. Specimens underwent six-hour treatments at 670 and 770 °C using vacuum heat. Results revealed distinct mechanical features in the coating: Vickers hardness reached 755, scanning electron microscope images displayed glassy phases, showcasing good wear resistance and compressive residual stresses at around −55 MPa. A remarkable 122% increase in compressive residual stress was noted through combined vacuum heat treatment and sandblasting. Volume wear decreased from the initial 18 to 14 mm3 after treatment at 670 °C followed by sandblasting, indicating a 30% enhancement in wear resistance. Yet, using vacuum heat treatment at 770 °C negatively impacted the coating's properties. [ABSTRACT FROM AUTHOR]

The evolution characteristics of pores and fractures in coal after liquid carbon dioxide (CO2) phase change are important factors that determine the permeability increase effect. Therefore, it is critical to correctly understand the influences of liquid CO2 phase change on pores and fractures in coal. The changes of adsorption and desorption isotherm, pore size, pore volume, and specific surface area of fractured coal and fractured coal were compared by low temperature liquid nitrogen adsorption experiment. In addition, a scanning electron microscope was adopted to observe fracture characteristics of fractured and unfractured coal samples and analyze changes in the connectivity and fracture development. Experimental results show that the fractured coal samples exhibit better hysteresis loops and a larger proportion of gas desorption than the unfractured ones. Fractured coal samples contain more developed pores and fractures compared with unfractured ones, and their fragmentation degree, pore diameter, fracture width, and connectivity of pores and fractures are also better. Besides, the closer the samples from the fracturing boreholes are, the better the fracturing effect. This indicates that liquid CO2 phase change can effectively enhance the gas transport capacity in pores and fractures in coal. The research results provide a solid basis for the better application of liquid CO2 phase‐change fracturing to the prevention of coal and gas outburst disasters and the realization of efficient gas extraction in deep coal seams. [ABSTRACT FROM AUTHOR]

The community structure and ecological function of marine ecosystems are critically dependent on phytoplankton. However, our understanding of phytoplankton is limited due to the lack of detailed information on their morphology. To address this gap, we developed a framework that combines scanning electronmicroscopy (SEM) with photogrammetry to create realistic 3D (three-dimensional)models of phytoplankton. The workflow of this framework is demonstrated using two marine algal species, one dinoflagellate Prorocentrum micans and one diatom Halamphora sp. The resulting 3D models are made openly available and allow users to interact with phytoplankton and their complex structures virtually (digitally) and tangibly (3D printing). They also allow for surface area and biovolume calculations of phytoplankton, as well as the exploration of their light scattering properties, which are both important for ecosystem modeling. Additionally, by presenting these models to the public, it bridges the gap between scientific inquiry and education, promoting broader awareness on the importance of phytoplankton. [ABSTRACT FROM AUTHOR]

Additive manufacturing of components with enhanced characteristics to combine the geometrical flexibility of layer-by-layer manufacturing and the remarkable thermomechanical and optical properties of advanced materials has become a focus for research in the last decades. In this investigation, in-house developed Al 2 O 3 slurries mixed with either MgO or MgAl 2 O 4 were digitally light processed and the resulting green parts underwent slow thermal debinding at low heating rates to produce dense and stable brown samples, which were subsequently subjected to different sintering regimes to obtain translucent samples. Air sintering trials were conducted at 1700 °C and the effect of different heating rates and holding times at the sintering temperature were investigated. In addition, vacuum sintering at 1600 °C was conducted for the best conditions to assess the effect of an oxygen-reduced atmosphere. Geometrical dimensions and density data were collected at the brown and fired stages to observe their evolution through the process with the help of high-magnification optical microscopy. Scanning electron microscope (SEM) images of the sintered samples were collected to observe and characterise the obtained microstructure. In addition, X-ray diffraction (XRD) was used to identify the crystal structure and assess the insurgence of secondary phases. Finally, total transmittance and in-line transmittance were measured to evaluate the translucency level achieved by the produced sintered samples. Translucent alumina samples exhibiting a maximum total transmittance of 90.4% and a maximum real in-line transmittance (RIT) of 16.9% in the visible and near-infrared regions were fabricated. [ABSTRACT FROM AUTHOR]

NiSi–NiCr thin film thermocouples (TFTCs) have significant application value as contact temperature sensors in cutting temperature measurements owing to their fast response and negligible volume. However, due to the relatively high chemical activity of Ni-based alloys, high-temperature oxidation strongly affects the operational reliability of NiSi–NiCr TFTCs. In this respect, depositing an anti-oxidation coating onto the surface of NiSi–NiCr TFTCs is considered an effective way to protect them in high-temperature environments. In this study, NiSi and NiCr films were deposited on cemented carbides and annealed at 200 °C–600 °C in air. Scanning electron microscope, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and four-probe resistivity tests were used to characterize the microstructure and resistivity of NiSi and NiCr film. Then SiN x O y films were deposited onto the NiSi and NiCr films and compared with uncoated samples after annealing at 600 °C. The effect of SiN x O y films on the thermal stability and thermoelectric output of NiSi–NiCr TFTCs was investigated. The results show that the NiSi film was partially oxidized at 200 °C and entirely oxidized when the temperature exceeded 400 °C. The completely oxidized NiSi films had evident defects and cracks, and the resistivity increased by a factor of over 1000. The NiCr film could not be completely oxidized at 600 °C, which is attributed to the formation of Cr 2 O 3 as an external oxide barrier layer. Below 600 °C, SiN x O y films could effectively protect NiSi and NiCr films from oxidation. Thus, the addition of SiN x O y film increases the maximum temperature at which NiSi–NiCr TFTCs can be used. [ABSTRACT FROM AUTHOR]

This work's main objective is to assess the effects of wollastonite/fluorapatite glass (G) and glass-ceramic (GC) on tricalcium silicate's (TCS) bioactivity and physico-mechanical properties. To achieve this goal, 10 and 20 wt percent of G or GC were used in place of TCS. The constructed specimens were kept submerged in SBF solution for 4 weeks at a temperature of approximately 37 ± 0.5 °C to create the hydroxyapatite layer (HA) on the cement paste surface and evaluate their biological behavior. Additionally measured were bulk density, apparent porosity, and compressive strength. The principal components had been studied using X-ray diffraction and Fourier transform infrared spectroscopy. An energy dispersive spectroscopy (EDS)-equipped scanning electron microscope (SEM) was used to examine the materials' morphology. The antibacterial and cytotoxic properties were also evaluated. The findings demonstrated that during soaking in SBF, bulk density and porosity ranged from 1.38 to 1.5 g/cm3 and from 44.99 to 39.12 %, respectively, and the results for compression strength varied from 65 to 88 MPa. The outcomes demonstrated that all of the prepared samples' surfaces had the hydroxyapatite layer (HA) formed on them following their immersion in the biological fluid (SBF). Additionally, it was discovered that raising the percentage of GC (TCS/20GC) in synthetic samples improves TCS cement's physico-mechanical and bioactivity characteristics. Furthermore, these substances had minimal cytotoxic effects on the typical fibroplast cell line of humans (BJ1), indicating their potential utility in dental applications. Ultimately, the antimicrobial test demonstrated good inhibitory behavior against the pathogens Bacillus cereus, Staphylococcus aureus, and Pseudomonas aeruginosa. [ABSTRACT FROM AUTHOR]

In this study, zinc oxide nanoparticles (Zn-NPs) were prepared by the green synthesis method and loaded inside niosomes as a drug release system and their physicochemical and biological properties were determined. Zn-NPs were prepared by the eco-friendly green strategy, the structure, and morphological properties were studied and loaded into niosomes. Subsequently, different formulations of niosomes containing Zn-NPs were prepared and the optimal formulation was used for biological studies. Scanning electron microscope (SEM) and dynamic light scattering (DLS) were used to investigate the morphology and size of nanoparticles. Fourier transform infrared spectroscopy (FTIR) and UV–Vis were used to confirm the synthesis of Zn-NPs. Energy dispersive X-ray spectrometer (EDS) determined the elemental analysis of the Zn-NPs synthesis solution and the crystalline structure of Zn-NPs was analysed by XRD (X-Ray diffraction). Furthermore, Zn-NPs were loaded inside the niosomes, and their structural characteristics, entrapment efficiency (EE%), the release profile of Zn-NPs, and their stability also were assessed. Moreover, its antimicrobial properties against some microbial pathogens, its effect on the expression of biofilm genes, and its anticancer activity on the breast cancer cell lines were also determined. To study the cytocompatibility, exposure of niosomes against normal HEK-293 cells was carried out. In addition, the impact of niosomes on the expression of genes involved in the apoptosis (Bcl2, Casp3, Casp9, Bax) at the mRNA level was measured. Our findings revealed that the Zn-NPs have a round shape and an average size of 27.60 nm. Meanwhile, UV–Vis, FTIR, and XRD results confirmed the synthesis of Zn-NPs. Also, the EE% and the size of the optimized niosomal formulation were 31.26% and 256.6 ± 12 nm, respectively. The release profile showed that within 24 h, 26% of Zn-NPs were released from niosomes, while in the same period, 99% of free Zn-NPs were released, which indicates the slow release of Zn-NPs from niosomes. Antimicrobial effects exhibited that niosomes containing Zn-NPs had more significant antimicrobial and anti-biofilm effects than Zn-NPs alone, the antimicrobial and anti-biofilm effects increased 2 to 4 times. Cytotoxic effects indicated that when Zn-NPs are loaded into niosomes, the anticancer activity increases compared to Zn-NPs alone and has low cytotoxicity on cancer cells. Niosomes containing ZnNPs increased the apoptosis-related gene expression level and reduced the Bcl2 genes. In general, the results show that niosomes can increase the biological effects of free Zn-NPs and therefore can be a suitable carrier for targeted delivery of Zn-NPs. [ABSTRACT FROM AUTHOR]

CuO:ZnO nanocomposite photocatalyst with tunable ratios of CuO was synthesized using a low-temperature-assisted co-precipitation method, which is suitable for industrial-scale production. Analytical techniques, including XRD, FE-SEM, HR-TEM, FTIR, XPS and UV–Vis, were utilized to investigate the structure, morphological characteristics, chemical composition and optical properties of the CuO:ZnO nanocomposite. The XRD analysis reveals that the samples exhibit a single phase, characterized by a wurtzite hexagonal structure of ZnO and a monoclinic structure of CuO. The average crystal size changed from 37.3±8.8nm to 24.6±6.9nm when CuO varied from 0% to 5% in the CuO:ZnO nanocomposite. The scanning electron microscope (SEM) images reveal that the nanocomposite particles exhibit a high degree of uniformity, with an average size of approximately 50nm. HR-TEM shows the width of lattice plane families consistent with X-ray diffraction for CuO and ZnO materials. The ZnO exhibits a unique hexagonal shape. Furthermore, there is a slight correlation between the CuO fraction and an increase in grain size. FTIR analysis revealed the specific vibrational modes of ZnO and CuO at wavenumbers of 564, 619, 651, 673 and 488, 607cm−1, respectively. XPS shows secondary valences of Cu and Zn indicating the formation of CuO and ZnO while the high Ov peak indicates the presence of Oxygen defects in the crystal lattice. The absorption results clearly demonstrate the presence of two absorption edges corresponding to ZnO and CuO, as well as the broadening of the absorption spectrum of the nanocomposite sample up to a wavelength of 840nm. The photocatalytic degradation of RhB yielded remarkable outcomes, as the concentration of RhB declined by 98.6% after 20min of illumination using a CuO:ZnO (3:97) nanocomposite. The photocatalytic efficiency is significantly influenced by changing the CuO ratio in CuO:ZnO nanocomposites. This can be attributed to the tradeoff between the effectiveness of the heterogeneous contact layer and the limited ability of CuO to catalyze photochemical reactions. Based on the scavenger test, hydroxyl and superoxide radicals are primarily responsible for the decolorization of RhB dye. Results of evaluating the reusability and stability of the material show that, after fifth recycling, the decomposition efficiency still reaches over 90% after 30min of illumination. [ABSTRACT FROM AUTHOR]

We conduct in situ tensile straining experiments to investigate the role of hydrogen and slip in crack initiation in nickel-based alloy 725. Our experiments reveal no tendency for hydrogen to enhance localized slip and no necessity of slip for crack initiation. We use electrochemical charging to introduce hydrogen into samples, melt extraction to measure hydrogen content, and digital image correlation to analyze localized plastic strains during in situ tensile tests in a scanning electron microscope. Cracks initiate both in regions with and without nearby localized slip. Moreover, the fraction of cracks initiating with no nearby slip is greater at higher hydrogen content. Slip-assisted crack initiation generally occurs at locations where intergranular slip is arrested, especially at intersections of slipping coherent twin boundaries with thin twin lamellae. Cracks that initiate without nearby slip occur at a wider variety of microstructural features, including inclusions, triple junctions, and surface flaws. [ABSTRACT FROM AUTHOR]

During rock drilling, a drill bit will wear as it breaks the rock. However, there is no uniform grading standard for rock abrasiveness. To solve this problem, the wear mechanisms of a polycrystalline diamond compact (PDC) bit and the formation it is drilling into are analyzed in depth, and an abrasiveness evaluation method based on the fractal dimension of the rock surface topography is established. Initially, a three-dimensional digital model is generated from a scanning electron microscope image of the rock after drilling; next, an evaluation of the irregularities on the rock surface is performed using an adapted Weierstrass–Mandelbrot (W-M) function to ascertain the fractal dimensionality. Then, the microcontact characteristics of the contact surface between the formation and the PDC bit are analyzed, and the distribution of the microconvex contact points of the two-body friction pair in a region is obtained. Because the sliding friction between the drill bit and the rock produces a large amount of heat, according to the contact area formula of the friction surface and heat conduction theory, the temperature rise and overall temperature distribution of the formation and PDC bit under the condition of sliding friction are revealed, and the real contact area between the formation and the drill bit within a certain temperature range is obtained. Finally, the evaluation index of rock abrasiveness under sliding conditions is established by adopting the wear weight loss of the rock cutting tool per unit volume as the index of rock abrasiveness, and the model is verified by a microdrilling experiment. The research in this paper is highly important for improving the rock-breaking efficiency and bit service life during drilling. [ABSTRACT FROM AUTHOR]

Lately, children's daily consumption of some products, such as cereals and candies, has been rising, which provides a compelling rationale for determining any metallic substances that may be present. Monitoring the concentration of certain metals, like nickel, in these products is necessary due to medical issues in humans when consumed regularly. So, in this work, a novel and highly selective carbon paste as a Ni(II) ion-selective sensor was prepared and investigated using ceramic magnesium aluminum spinel nanoparticles as the ionophore and tritolyl phosphate (TOCP) as a plasticizer. A modified co-precipitation method was used to synthesize the spinel nanoparticles. X-ray diffraction, scanning electron microscope with EDAX, transmission electron microscope, and BET surface area were used to determine the phase composition, microstructure, pores size, particle size, and surface area of the synthesized nanoparticles. The spinel nanoparticle was found to have a nano crystallite size with a cubic crystal system, a particle size ranging from 17.2 to 51.52 nm, mesoporous nature (average pore size = 8.72 nm), and a large surface area (61.75 m2/g). The composition ratio of graphite carbon as a base: TOCP as binder: spinal as ionophore was 67.3:30.0:2.7 (wt%) based on potentiometric detections over concentrations from 5.0 × 10−8 to 1.0 × 10−2 mol L−1 with LOD of 5.0 × 10−8 mol L−1. A measurement of 29.22 ± 0.12 mV decade−1 over pH 2.0–7.0 was made for the Nernstian slope. This sensor demonstrated good repeatability over nine weeks and a rapid response of 8 s. A good selectivity was shown for Ni(II) ions across many interferents, tri-, di-, and monovalent cations. The Ni(II) content in spiked real samples, including cocaine, sweets, coca, chocolate, carbonated drinks, cereals, and packages, were measured. The results obtained indicated no significant difference between the proposed potentiometric method and the officially reported ICP method according to the F- and t-test data. In addition to utilizing ANOVA statistical analysis, validation procedures have been implemented, and the results exceed the ICP-MS methodology. [ABSTRACT FROM AUTHOR]

Bi-doped Sn–Ag–Cu (SAC) microelectronic solder is gaining attention for its utility as a material for solder joints that connect substrates to printed circuit boards (PCB) in future advanced packages, as Bi-doped SAC is reported to have a lower melting temperature, higher strength, higher wettability on conducting pads, and lower intermetallic compound (IMC) formation at the solder-pad interface. As solder joints are subjected to aging during their service life, an investigation of aging-induced changes in the microstructure and mechanical properties of the solder alloy is needed before its wider acceptance in advanced packages. This study focuses on the effects of 1 to 3 wt.% Bi doping in an Sn–3.0Ag–0.5Cu (SAC305) solder alloy on aging-induced changes in hardness and creep resistance for samples prepared by high cooling rates (>5 °C/s). The specimens were aged at ambient and elevated temperatures for up to 90 days and subjected to quasistatic nanoindentation to determine hardness and nanoscale dynamic nanoindentation to determine creep behavior. The microstructural evolution was investigated with a scanning electron microscope in tandem with energy-dispersive spectroscopy to correlate with aging-induced property changes. The hardness and creep strength of the samples were found to increase as the Bi content increased. Moreover, the hardness and creep strength of the 0–1 wt.% Bi-doped SAC305 was significantly reduced with aging, while that of the 2–3 wt.% Bi-doped SAC305 increased with aging. The changes in these properties with aging were correlated to the interplay of multiple hardening and softening mechanisms. In particular, for 2–3 wt.% Bi, the enhanced performance was attributed to the potential formation of additional Ag3Sn IMCs with aging due to non-equilibrium solidification and the more uniform distribution of Bi precipitates. The observations that 2–3 wt.% Bi enhances the hardness and creep strength of the SAC305 alloy with isothermal aging to mitigate reliability risks is relevant for solder samples prepared using high cooling rates. [ABSTRACT FROM AUTHOR]

Identification of changes occurring on the working surface of lubricated gears using analytical equipment, e.g., an FE-SEM scanning electron microscope with an EDS microanalyzer, a WLI interferometric microscope, or a GDEOS optical discharge spectrometer, enables the characterisation of wear mechanisms of this surface. Definition of the phenomena occurring on the surface of tribo-couples after scuffing tests enables a comparative analysis of scuffing resistance and surface properties of the micro- and nanostructure, and elemental composition of the tested gears. Recognition and analysis of the wear mechanisms occurring on the working surface of gears will reduce the risk of damage and losses resulting from the need for maintenance and repair. The study concerned the working surfaces of gears made of 17HNM and 35HGSA steels on which a W-DLC/CrN coating was deposited. Shell Omala S4 GX 320 commercial industrial oil with a synthetic PAO (polyalphaolefin) base was selected for the lubrication of the gears. Tribological tests employed an FZG gear scuffing under severe conditions test method and they were carried out on a T-12U test rig for cylindrical gear analysis. [ABSTRACT FROM AUTHOR]

Considering the high demand for innovative solutions in medicine, a major increase in interest in biomaterials research has been noticed, with the most significant advancements in metals and their alloys. Titanium-based alloys are one of the most recognised in the scientific community but do not represent the only way to achieve optimal results. Zirconium alloys for medical applications are a novelty with significant research potential based on their outstanding properties, which may be of value for medicine. The aim of the present study was to obtain new biomedical Zr-Nb-Mo alloys with varying ratios of their respective elements—Zr and Mo—using combined powder metallurgy (PM) and arc melting (VAM) methods. The obtained samples underwent microstructure analysis using an optical microscope (OM) and a scanning electron microscope (SEM). The study of element distribution was conducted with energy dispersive spectroscopy (EDS), whereas the phase composition was determined using X-ray diffraction (XRD). Mechanical properties were examined with a Micro Combi Tester MCT3, whereas tribological properties were assessed with a TRN Tribometer, and Ringer's solution was used as a lubricant. Additionally, the wear tracks of the studied samples were observed using the SEM. The research results indicated that increased Mo content conduced to microstructure refinement and homogeneity. Furthermore, the higher content of this element contributed to the growth of the HVIT, HIT, and EIT parameters, together with the improvement in the tribological performance of the alloys. XRD analysis revealed that the obtained samples were multiphase, and raising the Mo addition promoted the formation of new phases, including a ternary phase—Zr0.9Nb0.66Mo1.44 (Fd 3 ¯ m). The chemical composition study showed uneven distribution of niobium and areas of uneven mutual distribution of zirconium and molybdenum. [ABSTRACT FROM AUTHOR]

In this paper, the deformation behavior of UNS S32750 (S32750) duplex stainless steel during low cycle fatigue was studied by controlling the number of cycles. The microstructure of the specimens under different cycles was characterized by optical microscope (OM), scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscope (TEM). The microhardness of the two phases was measured by a digital microhardness instrument. The results showed that the microhardness of ferrite increases significantly after the first 4000 cycles, while the austenite shows a higher strain hardening rate after fatigue fracture, and the microhardness of ferrite and austenite increases by 23 HV and 87 HV, respectively. The two-phase kernel average misorientation (KAM) diagram showed that the continuous accumulation of plastic deformation easily leads to the initiation of cracks inside the austenite and at the phase boundaries. The evolution of dislocation morphology in the two phases was obviously different. With the increase in cycle number, the dislocation in ferrite gradually transforms from dislocation bundles and a dislocation array to a sub-grain structure, while the dislocation in austenite gradually develops from dipole array to an ordered Taylor lattice network structure. [ABSTRACT FROM AUTHOR]

Nanoscale geranium waste (GW) and magnesium nanoparticle/GW nanocomposites (Mg NP/GW) were prepared using green synthesis. The Mg NP/GW samples were subjected to characterization using X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR-FT). The surface morphology of the materials was examined using a scanning electron microscope (SEM), and their thermal stability was assessed through thermal gravimetric analysis (TG). The BET-specific surface area, pore volume, and pore size distribution of the prepared materials were determined using the N2 adsorption–desorption method. Additionally, the particle size and zeta potentials of the materials were also measured. The influence of the prepared nanomaterials on seed germination was intensively investigated. The results revealed an increase in seed germination percent at low concentrations of Mg NP/GWs. Upon treatment with Mg NP/GW nanoparticles, a reduction in the mitotic index (MI) was observed, indicating a decrease in cell division. Additionally, an increase in chromosomal abnormalities was detected. The efficacy of GW and Mg NP/GW nanoparticles as new elicitors was evaluated by studying their impact on the expression levels of the farnesyl diphosphate synthase (FPPS1) and geranylgeranyl pyrophosphate (GPPS1) genes. These genes play a crucial role in the terpenoid biosynthesis pathway in Sinapis alba (S. alba) and Pelargonium graveolens (P. graveolens) plants. The expression levels were analyzed using reverse transcription–quantitative polymerase chain reaction (RT-qPCR) analysis. The qRT-PCR analysis of FPPS and GPPS gene expression was performed. The outputs of FPPS1 gene expression demonstrated high levels of mRNA in both S. alba and P. graveolens with fold changes of 25.24 and 21.68, respectively. In contrast, the minimum expression levels were observed for the GPPS1 gene, with fold changes of 11.28 and 6.48 in S. alba and P. graveolens, respectively. Thus, this study offers the employment of medicinal plants as an alternative to fertilizer usage resulting in promoting environmental preservation, optimal waste utilization, reducing water consumption, and cost reduction. [ABSTRACT FROM AUTHOR]

Methylene blue dye in water sources can pose health risks to humans, potentially causing methemoglobinemia, a condition that impairs the blood's ability to carry oxygen. Hence, the current study investigates the synthesis of novel magnesium borate/magnesium oxide (Mg3B2O6/MgO) nanostructures and their efficiency in removing methylene blue dye from aqueous media. The nanostructures were synthesized using the Pechini sol–gel method, which involves a reaction between magnesium nitrate hexahydrate and boric acid, with citric acid acting as a chelating agent and ethylene glycol as a crosslinker. This method helps in achieving a homogeneous mixture, which, upon calcination at 600 and 800 °C, yields Mg3B2O6/MgO novel nanostructures referred to as MB600 and MB800, respectively. The characterization of these nanostructures involved techniques like X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, N2 gas analyzer, and field-emission scanning electron microscope (FE-SEM). These analyses confirmed the formation of orthorhombic Mg3B2O6 and cubic MgO phases with distinct features, influenced by the calcination temperature. The mean crystal size of the MB600 and MB800 samples was 64.57 and 79.20 nm, respectively. In addition, the BET surface area of the MB600 and MB800 samples was 74.63 and 64.82 m2/g, respectively. The results indicated that the MB600 sample, with its higher surface area, generally demonstrated better methylene blue dye removal performance (505.05 mg/g) than the MB800 sample (483.09 mg/g). The adsorption process followed the pseudo-second-order model, indicating dependency on available adsorption sites. Also, the adsorption process matched well with the Langmuir isotherm, confirming a homogeneous adsorbent surface. The thermodynamic parameters revealed that the adsorption process was physical, exothermic, and spontaneous. The MB600 and MB800 nanostructures could be effectively regenerated using 6 M HCl and reused across multiple cycles. These findings underscore the potential of these nanostructures as cost-effective and sustainable adsorbents for methylene blue dye removal. [ABSTRACT FROM AUTHOR]

Residual melon by-products were explored for the first time as a bioresource of microcrystalline cellulose (MCC) obtention. Two alkaline extraction methods were employed, the traditional (4.5% NaOH, 2 h, 80 °C) and a thermo-alkaline in the autoclave (2% NaOH, 1 h, 100 °C), obtaining a yield of MCC ranging from 4.76 to 9.15% and 2.32 to 3.29%, respectively. The final MCCs were characterized for their chemical groups by Fourier-transform infrared spectroscopy (FTIR), crystallinity with X-ray diffraction, and morphology analyzed by scanning electron microscope (SEM). FTIR spectra showed that the traditional protocol allows for a more effective hemicellulose and lignin removal from the melon residues than the thermo-alkaline process. The degree of crystallinity of MCC ranged from 51.51 to 61.94% and 54.80 to 55.07% for the thermo-alkaline and traditional processes, respectively. The peaks detected in X-ray diffraction patterns indicated the presence of Type I cellulose. SEM analysis revealed microcrystals with rough surfaces and great porosity, which could remark their high-water absorption capacity and drug-carrier capacities. Thus, these findings could respond to the need to valorize industrial melon by-products as raw materials for MCC obtention with potential applications as biodegradable materials. [ABSTRACT FROM AUTHOR]

Jute is an inherent lignocellulosic fiber, consisting of hemicellulose, α-cellulose, and lignin. Industrial ventilation, automotive composites, upholstery, carpets, military uniforms, hospital furnishings, and curtains necessitate the integration of flame-retardance properties into jute fibers. In this investigation, seven weave-structured jute fabrics were treated using an organophosphorus-based flame-retardant (FR) chemical (ITOFLAM CPN) and a crosslinking agent (KNITTEX CHN) by the pad–dry–cure method. The thermal stability, degradation and pyrolysis behavior of jute was measured using a thermogravimetric analyzer (TGA). Surface morphology and element distribution were scrutinized utilizing a scanning electron microscope (SEM) and an energy-dispersive spectrometer (EDS). The ATR-FTIR (Attenuated Total Reflection-Fourier Transform Infrared Spectrometer) technique has been employed for analyzing the composition of chemicals in the jute fabrics. According to the protocols specified in ISO 14184-1, free formaldehyde detection was carried out on the jute fabrics. The flame-retardance property was significantly improved on all of the jute fabrics after FR treatment. FTIR and SEM-EDS studies revealed the presence of FR chemical deposition on the surface of the jute fabrics. TGA analysis indicated that the fabrics treated with FR exhibited premature degradation, leading to the generation of more char compared to untreated samples. The jute fabrics specifically demonstrated a notable enhancement in residual mass, exceeding 50% after FR treatment. However, it is noteworthy that the FR-treated fabrics exhibited an elevated level of free formaldehyde content, surpassing the permissible limit of formaldehyde in textiles intended for direct skin contact. The residual mass loss percentage after ten washes of FR-treated fabrics remained in a range from 32% to 36%. Twill weave designed fabrics (FRD4 and FRD5) clearly showed a lower thermal degradation temperature than the other weaves used in this study. [ABSTRACT FROM AUTHOR]

This work aims to modify the surface characteristics of cerium oxide (ceria, CeO 2) nanoparticles using different surface modification strategies for improved CeO 2 nanoparticle dispersion and suspension stability. Analysis and discussion were conducted on the two surface modification processes used by a cationic surfactant like hexadecyl cetyltrimethylammonium bromide (CTAB) and a silane agent like tetraethyl orthosilicate (TEOS). Untreated CeO 2 was used as reference material. The dispersion effect of surface-modified CeO 2 nanoparticles at different pHs was determined by zeta potential measurements. Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Particle size analysis (PSA), Thermogravimetric analysis (TGA), Scanning electron microscope (SEM), Brunauer–Emmett–Teller analysis (BET), and X-ray diffraction (XRD) were used to confirm the efficacy of the surface modification of CeO 2 nanoparticles. First, the results obtained in this experimental work demonstrate that both advanced modifications greatly enhance the dispersion and suspension stability of surface-modified CeO 2 nanoparticles in comparison with untreated CeO 2 nanoparticles. Second, it is also shown that the surface-modified CeO 2 nanoparticles obtained through a silanization surface process with TEOS silane agent had a better dispersion effect and dispersion stability than the surface-modified CeO 2 nanoparticles obtained by surface modification with CTAB cationic surfactant. These results can help better understand how advanced surface modifications can assist the application of well-dispersed CeO 2 nanoparticles in technological applications. [Display omitted] • Surface modification significantly improved the aqueous dispersion and stability of CeO 2 nanoparticles. • The modification improved the CeO 2 dispersion by increasing the spacing and negative charge. • CeO2 dispersion was optimal at a specific pH, with a significant effect of pH. • The modification strategy is crucial for the performance of CeO 2 in technological applications. [ABSTRACT FROM AUTHOR]