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Solvent evaporation was used to create a novel organic Schiff-based optical crystal of Benzimidazolium gallate (BGA). The size of unit cells was determined using X-ray diffraction analysis. Fourier transform infra-red spectrum analysis revealed chemical bonds' vibrational behavior and their functional groups' existence. Optical transparency and optical bandgap (3.66 eV) were observed by the UV–visible-near infrared spectral analysis. Differential scanning calorimetry curves show that decomposition is exhibited at 215 °C. Dielectric experiments on the BGA crystal were performed at ambient temperature. High-resolution scanning electron microscope analysis shows the crystal's nature and surface shape. The Z-scan process explored the BGA crystal's nonlinearity, and the crystal is suitable for photonic, optoelectronic, and optical-limiting applications. [ABSTRACT FROM AUTHOR]

In the current study, a novel electrochemical sensor has been developed for levofloxacin detection, by coating an Indium tin oxide (ITO) modified electrode with a thin film of Cu-nanoplatelets, WO3 quantum dots coupled to the g-C3N4 nanosheets. The prepared electrode was characterized using various analytical tools, including powder X-ray diffraction (XRD), scanning electron microscope (SEM), high resolution transmission electron microscope (HRTEM) and Fourier-Transform Infrared spectroscopy (FT-IR). The electrochemical properties of levofloxacin (LEVO) were determined by performing cyclic voltammetry (CV) and amperometric tests. The hybrid electrode exhibits a well-defined peak around 1.2 V during the anodic potential scan, which was attributed to the (LEVO) oxidation process. The measured ultrahigh sensitivity is 0.786 µA µM−1 cm−2 for a linear range of 0–70 µM in the low concentration zone and 0.312 µA µM−1 cm−2 for a linear range of 120–870 µM in the high concentration zone. A good linear correlation between the peak current and LEVO concentration in the range of 0 to 70 µM was obtained through detection and quantification limits of 0.1 µM and 0.3 µM, respectively.The WO3/g-C3N4/Cu nanoparticles that modified the ITO electrode reveals high stability, reproducibility, and repeatability, as well as selectivity for LEVO in real water samples. Analyses were also conducted on the LEVO detection in the presence of interfering substances.As far as this paper is concerned, this is the first time that a ternary nanocomposite WO3/g-C3N4/Cu has been used to detect LEVO at low and high concentrations. Application of ITO/WO3/g-C3N4/Cu as an electrochemical sensor for LEVO [ABSTRACT FROM AUTHOR]

Cement-based cementing materials have some disadvantages, such as high brittleness and poor mechanical properties. In the long-term production process of oil and gas wells, it is easy to damage, resulting in annulus pressure and interlayer channeling. However, curable resin-based cementing materials have the advantages of good toughness, high strength, and low elastic modulus, and have the potential as cementing materials. A water-based epoxy resin cementing fluid system suitable for cementing was obtained in this article, which has good toughness and high strength, and can directly replace cement slurry for cementing. When the temperature was 50 °C and 70 °C, the fluidity of water-based epoxy resin cementing fluid system was greater than 18 cm, and the thickening time was 74 minute and 128 minute, respectively. The 28 day compressive strength of the resin cured at 70 °C increased by 276.3% and the tensile strength increased by 117.9% compared with the blank cement paste. Scanning electron microscope test indicated that the matrix of water-based epoxy resin is denser than that of blank cement paste. Fourier transform infrared spectrometer and X-ray diffraction analyses demonstrate that the cured epoxy resin products are not affected by curing age. According to the thermogravimetric results, epoxy resin can be used in high temperature deep well. On the whole, replacing cement with water-based epoxy resin cementing fluid can improve the cementing quality, which has broad application value. [ABSTRACT FROM AUTHOR]

The new period of science and technology implies control over the size and shape of materials. In determining the properties and potential application of materials the morphology variation plays an important role. The present study focuses on the fabrication of calcium oxalate (CaC2O4) in a nano range having uniform and novel particle morphology. The powder materials having monodispersed particles of plate-like and donut-shaped morphologies were successfully synthesized by a controlled precipitation method under extensively optimized experimental parameters. The morphology of the as-prepared uniform fine particle systems was studied by scanning electron microscope and the mechanical functional surface groups and crystallinity of the test material were examined by Fourier transform infrared spectroscopy (FT-IR) and (XRD) X-ray diffraction analysis, respectively. The effect of different parameters on calcium oxalate particle morphology was also investigated. The observed results explored a significant effect of technological parameters on particle size, shape, and uniformity. Therefore, monodispersed unique particle systems of calcium oxalate were synthesized under a narrow set of experimental conditions through a reproducible recipe protocol. [ABSTRACT FROM AUTHOR]

Zeolitic Imidazole Frameworks (ZIFs) are prospective porous materials as catalyst support due to their relatively large surface area, and tunability in size, structure, and porosity. Recent studies have also shown that ZIF is the best candidate for various catalytic redox reactions such as the oxidation of benzyl aromatic hydrocarbons. In this study, the synthesized Pt catalyst supported on Co-ZIF was varied by the organic ligands: imidazole, benzimidazole, and 1- (3-aminopropyl) imidazole, then followed by impregnation of Pt precursor. The catalysts were characterized its physical and chemicals properties such as Fourier Transform Infrared (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), and Brunauer Emmet Teller (BET), Temperature-Programmed Desorption (NH3-TPD and CO2-TPD). The prepared catalysts were evaluated for catalytic hydrocracking and hydroisomerization of n-hexadecane in a 100 ml-batch reactor. GC-MS analysis presented that the Pt/ZIF catalyst with imidazole ligands has better performance than others. Hence, the optimization of n-Hexadecane conversion was carried out by the Pt/ZIF-imidazole catalyst varying the amount of metal loading, time and temperature reaction. The results showed that the reaction temperature of 350 °C using 20 bar H2 for 4 h and the addition of 15 wt% Pt successfully achieved 90.77% conversion and produced the highest yield of isomers and alkanes, 4.04% and 35.75%, respectively. [ABSTRACT FROM AUTHOR]

Research has been carried out on making biodiesel from palm oil using natural zeolite catalysts impregnated with metal oxides such as zinc oxide and titanium oxide. This research aims to produce biodiesel using natural zeolite and ZnO-TiO2/NZ catalysts. The catalysts were analyzed using X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Scanning Electron Microscope (SEM), and Brunauer-Emmet-Teller (BET). The catalyst was tested in the transesterification reaction to produce biodiesel. The oil and methanol mole ratio varied from 1:15, 1:18, and 1:20. In addition, the biodiesel product was analyzed using Gas Chromatography-Mass Spectroscopy (GC-MS). The results showed the optimum condition for converting triglycerides to 1:18 variation of oil:methanol mole ratio was 60.53% using a ZnO-TiO2/NZ catalyst. The ZnO-TiO2/NZ catalyst is very promising for use as a catalyst for converting palm oils into biodiesel. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of incorporating nanoparticles on the energy absorption properties of nanocomposites using low-velocity impact (LVI) testing and molecular modeling. Various types of thermoset polymer-based nanocomposites reinforced with carbon nanotubes (CNTs) and alumina were analyzed, and the effect of adding two types of nanofillers and microfiber as a filler material was investigated. The results show that the addition of nanoparticles significantly improved the elastic energy absorption properties of the nanocomposites at the atomic level. The LVI tests demonstrated that adding both types of nanoparticles, along with microfiber, significantly enhanced the energy absorption capacity of the four-phase composite under practical conditions. The scanning electron microscope (SEM) analyses revealed the morphology behavior of the nanoparticles. Incorporating both types of nanoparticles simultaneously with the polymer and fibers increased the elastic modulus by up to 163 %. These findings have significant implications for designing structures with energy-absorbing materials to reduce sports-related injuries. The use of nanocomposites with enhanced energy absorption properties can help to improve the performance of energy-absorbing structures and reduce the risk of sports-related injuries. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) multiferroic composites are more promising candidates for low-power consumption devices, next-generation spintronic devices, and multistate memory devices since they exhibit significantly higher Magnetoelectric interaction over single-phase multiferroics. In this regard magnetic behaviour, dielectric, and magnetoelectric characteristics of a novel Pb-free (1-x) Na 0.5 Bi 0.5 TiO 3 -(x) Ni 0.5 Co 0.5 Fe 2 O 4 , (x = 0, 0.2, 0.4, 0.6, 0.8 & 1) particulate composites were explored. Solid-state synthesis was adopted to prepare the single-phase Na 0.5 Bi 0.5 TiO 3 (NBT), Ni 0.5 Co 0.5 Fe 2 O 4 (NCFO), and their composites. The presence of rhombohedral NBT and cubic inverse spinel NCFO in the composites were confirmed with X-ray diffraction (XRD) patterns. Microstrain (ε) induced in the prepared samples was estimated by using the Williamson-Hall (W-H) method. The piezoelectric NBT phase shows the tensile strain and the ferromagnetic NCFO shows the comprehensive strain. Among all the composites 0.8NBT-0.2NCFO shows a higher strain value of 0.012%, and the decrement in the strain values was observed upon increases in ferrite concentration. Backscattered scanning electron microscope (BS-SEM) images revealed the existence of highly dense uniformly distributed elements and Energy dispersive spectroscopy (EDS) confirmed the existing elements in the composites. UV–vis absorbance spectra disclosed a rise in energy gap values from 1.14 eV to 3.0 eV with increasing NBT percentage. Variations of dielectric permittivity and dielectric loss with respect to AC frequency were studied at room temperature (RT), and the 0.2NBT-0.8NCFO sample shows a high dielectric permittivity of 8500 at ∼100Hz. M − H (Magnetization-Magnetic field) hysteresis loops demonstrate the pure ferrite phase has a coercive field (H c) = 578 Oe, remnant magnetization (M r) = 21.43 emu/g and saturation magnetization (M s) = 71.29 emu/g. The M s and M r values in the composites are enhanced with increasing ferrite percentage. Studies on ME behaviour of (1-x) NBT-(x) NCFO, (x = 0.2,0.4,0.6 & 0.8) show the coupling effect between both the phases at room temperature and the highest coupling coefficient value 3.16mV/Cm. Oe was observed for the 0.8NBT-0.2NCFO further the reasons and mechanisms are discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: Au stud bump bonding technology is an effective means to realize heterogeneous integration of commercial chips in the 2.5D electronic packaging. The purpose of this paper is to study the long-term reliability of the Au stud bump treated by four different high temperature storage times (200°C for 0, 100, 200 and 300 h). Design/methodology/approach: The bonding strength and the fracture behavior are investigated by chip shear test. The experiment is further studied by microstructural characterization approaches such as scanning electron microscope, energy dispersive spectrometer and so on. Findings: It is recognized that there were mainly three typical fracture models during the chip shear test among all the Au stud bump samples treated by high temperature storage. For solder bump before aging, the fracture occurred at the interface between the Cu pad and the Au stud bump. As the aging time increased, the fracture mainly occurred inside the Au stud bump at 200°C for 100 and 200 h. When aging time increased to 300 h, it is found that the fracture transferred to the interface between the Au stud bump and the Al Pad. Originality/value: In addition, the bonding strength also changed with the high temperature storage time increasing. The bonding strength does not change linearly with the high temperature storage time increasing but decreases first and then increases. The investigation shows that the formation of the intermetallic compounds because of the reaction between the Au and Al atoms plays a key role on the bonding strength and fracture behavior variation. [ABSTRACT FROM AUTHOR]

The accumulation of alkali residue has led to significant contamination of soil, air, and water, posing a hazardous threat to the environment. To address this issue, a technology and method for producing alkali residue–based lightweight soil were proposed to facilitate the reuse of alkali residue, and the feasibility of this method was demonstrated. Compression tests, X-ray diffraction, X-ray fluorescence spectrometry, and scanning electron microscope (SEM) were conducted to investigate the strength characteristics and hardening mechanism of the material. The results indicate that the compressive strength of the alkali residue–based lightweight soil increases linearly with wet density, age, content of portland cement, and ground granulated blast slag. The optimal water–solid ratio was determined to be 0.6. Specimens with low and high strength exhibited plastic and brittle failures, respectively. The primary contributors to the material's compressive strength were identified as hydrated calcium silicate, ettringite, monosulfur calcium sulfoaluminate hydrate, hydrated calcium aluminate, and Friedel's salt. The 28-d compressive strength of the alkali residue–based lightweight soil, with a water–solid ratio of 0.6 and a wet density of 800.0 kg/m3 , was measured to be 1.17 MPa, meeting the requirements for most filling projects. [ABSTRACT FROM AUTHOR]

Potholes are one of the common diseases of asphalt pavements. Cold patching asphalt mixtures (CPAM) are a common material for pothole repair. Reclaimed asphalt pavement (RAP) is a high-potential sustainable material that is commonly used in pavement construction. The aim of this study is to address the balance between performance improvement and cost reduction in CPAM. To achieve this objective, the CPAM was prepared with four different contents of cutback and 100% RAP (RAP-CPAM) and its performances were evaluated by laboratory tests. First, Fourier transform infrared spectroscopy (FTIR) test and scanning electron microscope (SEM) technique were used to analyze the diffusion mechanism between the cutback and the artificial aged binder. Then, the rationality of the cutback content was preliminary estimated by the mixing test and the draindown test. Finally, the adhesion performance, cohesion performance, strength, and resistance to water damage of RAP-CPAM were characterized through laboratory tests. From the FTIR test, the carbonyl index of aged asphalt layer decreased compared to that of the artificial aged binder as the storage time increased. Simultaneously, SEM imaging of the artificial aged binder showed less fractured surfaces after storage. The results of FTIR and SEM tests indicate that the cutback and the artificial aged binder were diffused. It was found that 1.6% content of cutback was slightly lower for RAP-CPAM, and 2.8% was not excessive. Boiling test results show that RAP-CPAM had good adhesion performance. Rolling screen test, Marshall stability test, and immersion Marshall test results reveal that RAP-CPAM had good cohesion performance, strength, and resistance to water damage. Based on the performance evaluation, the optimal content of cutback in RAP-CPAM was determined as about 2.4%–2.8%. In conclusion, the cutback and the RAP binder were successfully diffused, thereby ensuring good performances of RAP-CPAM. [ABSTRACT FROM AUTHOR]

Nanofluids have demonstrated incredible potential for application in various industries such as coolants. Metal oxides are widely used as solid particles in formulations of nanofluids due to their advantages. Metal oxide-based nanoparticles (NPs), ZnO NPs were fabricated by the ultrasonically assisted co-precipitation method. The structure and morphology of the synthesized ZnO NPs were characterized using an array of analytical techniques including X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The XRD results showed that the purity of ZnO was obtained. The investigated nanofluids remained stable for a long time without substantial sedimentation. The present study deals with the corrosion assessment of St37 steel in nanofluids prepared with various concentrations of ZnO NPs. A scanning electron microscope coupled with energy-dispersive X-ray spectroscopy was used to determine the surface characteristics and elemental composition of low-carbon steel specimens both before and after corrosion tests. Notably, the nanofluid containing 0.05% by weight of ZnO nanoparticles demonstrated the highest corrosion prevention efficiency among the prepared nanofluids. Furthermore, impedance spectroscopy measurements revealed that the corrosion resistance increased by 72.9% for the nanofluid containing 0.05 wt% ZnO NPs compared to the base fluid. These findings highlight the potential of ZnO nanoparticles as an environmentally friendly anti-corrosion compound in cooling systems, effectively reducing corrosion degradation. [ABSTRACT FROM AUTHOR]

In order to ensure the safe and stable operation of the side-blown furnace adopting new process, the corrosion damage mechanism of the magnesia-chrome brick of the side wall at the slag line in a side-blown copper smelting furnace was researched using a scanning electron microscope and an energy dispersive spectrometer. The results show that: (1) the magnesia-chrome bricks located at the slag line undergo alternating corrosion and infiltration of copper matte and slag, which is hardly to form a stable slag layer, resulting in a continuous cycle of infiltration-corrosion-spalling of magnesia-chrome bricks and the severest corrosion;the corrosion of the magnesia-chrome bricks above the slag line is slight, because the infiltration of copper matte in the bricks is obviously weaken, and a stable spinel and olivine dense layer is formed on the hot surface of the bricks, serving as a barrier against further penetration and corrosion of slag and copper matte to a certain extent; (2) although copper matte only penetrates along the pores and grain boundaries in magnesia-chrome bricks without participating in the corrosion reaction, it penetrates and wraps the matrix particles or grains, disrupting the direct bonding of magnesia-chrome bricks, destroying the stable structure of the original magnesia-chrome bricks and consequently reducing their resistance to slag and copper matte; (3) the copper matte primarily penetrates along the chromite particles, and gaps between periclase crystals after the precipitation of iron-rich spinel, which is disadvantageous for the resistance of magnesia-chrome bricks to the penetration and corrosion of SiO2-FeO slag. [ABSTRACT FROM AUTHOR]

The discharge of effluent polluted with heavy metals have become a growing concern for researchers around the world. This study evaluated the removal efficiency of commercial activated carbon and rice husk activated carbon as adsorbents for the removal of copper ion in water. A nominal size of 1 mm was obtained after sieving the Rice Husk, washed with distilled water, dried in an oven t at 80 ℃ for 12 hours, and pyrolyzed in a furnace at 550 ℃ for 30 minutes. The chars produced were later air-dried and then activated with lemon juice. The Rice Husk Activated Carbon (RHAC) and Commercial Activated Carbon (CAC) purchased from the market were both subjected to the following analyses: bulk density, X-ray Fluorescence (XRF), Brunauer-Emmett-Teller (BET), Scanning Electron Microscope (SEM) and Energy Dispersive X-ray (EDX) in order to characterise the adsorbents and to understand their suitability for the removal of copper ion in water. One of the properties of an adsorbent is large pores which is exhibited by the activated carbons as revealed by the SEM analysis. Likewise, the XRF and EDX analyses confirmed that the adsorbents had larger proportion of Silica (50.1 - 50.25%), Carbon (60.06 - 84.87 wt .%) and Oxygen (15.13 - 21.60 wt. %) which is a property of a good adsorbent. BET analysis showed that the surface areas of the rice husk activated carbon and the commercial activated carbon were 998.35 and 1208.25 m2/g, respectively. The bulk densities of the rice husk activated carbon and the commercial activated carbon were 0.3325 and 0.2812 g/cm3, respectively. The maximum removal efficiency using RHAC was observed at 60 ℃ and 120 minutes at 83.96 and 89.21 %, respectively while for CAC the maximum removal efficiency was observed at 60 ℃ at 84.61 % and 30 minutes at 83.3 %. Initial concentration of 20 mg/l was observed to have the highest removal efficiency for the two activated carbon specimens. The modelled effect of initial concentration, temperature and contact time on removal efficiency yielded R2 values of 1, 0.918; 1,1 and 1,1 respectively for the CAC and RHAC. [ABSTRACT FROM AUTHOR]

Textile dyes have a major issue of the contamination of water and are hazardous to aquatic environments. This work reports the development of an efficient process for iron oxide nanoparticle synthesis by a modified co-precipitation technique. The ultrasonic energy was used to enhance the synthesis of maghemite nanoparticles. A comprehensive study of vital process factors was carried out to develop the optimum conditions for synthesising pure Fe2O3 nanoparticles. The effect of process variables was modelled and analysed with Box–Behnken statistical design and response surface methodology using Design-Expert software. The best outcome with 25-nm size was achieved with optimum processing conditions at a pH level of 12, a temperature of 70 °C, and a time of 60 min. The end products were confirmed with X-ray diffraction. Further, the nanoparticles were characterised with a scanning electron microscope, BET, UV–visible spectrophotometer, and vibrating sample magnetometer. The method described here offers significant advantages over other techniques for the large-scale production of Fe2O3 nanoparticles in a short time compared to other procedures. The prepared maghemite nanoparticles were successfully employed for methylene blue (MB) dye adsorption from water. Further, different adsorption process parameters were examined thoroughly. The data was analysed using Langmuir and Freundlich isotherms, whereas the adsorption kinetics of dye were investigated by employing the pseudo-first- and pseudo-second-order models. Higher values of R2 showed better fitness of the experimental data on dye removal to the Freundlich isotherm model and pseudo-second-order kinetic model. The maximum adsorption capacity of maghemite nanoparticles was observed to be 96.52 mg g−1. The adsorbent maghemite nanoparticles can be easily restored and reused. The combination of facile desorption and effective regeneration positions the prepared maghemite nanoparticles as a compelling candidate for industrial wastewater treatment applications. [ABSTRACT FROM AUTHOR]

Background: Nanoparticles are increasingly being used as an alternative antibiotic to target microorganisms, particularly for treating bacterial infections. In current study it was recognized processes such as metal ion release, induction of oxidative stress, and non-oxidative mechanisms. Developing resistance to nanoparticles is challenging for bacterial cells due to the multiple simultaneous actions against microorganisms, and require several simultaneous gene alterations within the same bacterial cell. Objective: To determine the effect of the titanium dioxide nanoparticles (TiO2NPs) on the activity of the same bacteria that participate in dental caries (Staphylococcus aureus and Escherichia coli). Patients and Methods: The study included 50 patients who attended the dental clinic and took the samples by the wooden swap from the molar area (cervical area of inflamed gingiva and same samples taken from occlusal surface of molar). The collected samples were cultured on "Mannitol salt agar, Blood agar, and MacConkey's agar plates" for separation of the needed bacteria (Staphylococcus aureus and Escherichia coli) that showed wide spreading in the oral cavities and dental carries. TiO2NPs are then created using pulse laser ablation, followed by coating preparation the nanoparticles materials (using a hybrid sol-gel and organ silicate nanoparticles), and finally the prepared nanoparticles to the coating solution and local paint were used for antimicrobial activity of the separated bacteria using different concentrations of TiO2 in the cultures. Results: Characterization showed the phase of the TiO2NPs was spherical, with very few irregularly shaped particles, and had an average small size in millimeters. Antimicrobial activity results showed a strong bactericidal effect against Gram-positive bacteria and demonstrated greater sensitivity to TiO2 nanoparticles at lower concentrations when compared to Gram-negative bacteria. Conclusion: It was shown that nanotechnology promise in treating various infections caused by bacteria, including dental caries. Notably, nanoparticles have demonstrated broad-spectrum antibacterial effects against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

To simultaneously solve problems in an eco-friendly manner, introducing a waste residual as a sustainable conditioner to aid alum sludge dewatering is suggested as a cradle-to-cradle form of waste management. In this regard, the superiority of deep dewatering alum sludge with a powdered wood chip composite residual as a novel conditioner was explored, whereby traditional conventional conditioners, i.e., polyelectrolytes and lime, were substituted with powdered wood chips. Initially, Fe3O4 was prepared at the nanoscale using a simple co-precipitation route. Next, wooden waste was chemically and thermally treated to attain cellulosic fine powder. Subsequently, the resultant wood powder and Fe3O4 nanoparticles were mixed at 50 wt % to attain a wood powder augmented with iron, and this conditioner was labeled nano-iron-cellulose (nIC-Conditioner). This material (nIC-Conditioner) was mixed with hydrogen peroxide to represent a dual oxidation and skeleton builder conditioning substance. Characterization of the resultant conditioner was carried out using transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) transmittance spectrum analysis. The feasibility of the experimental results revealed that the moisture content in the sludge cake was lower after conditioning, and the capillary suction time (CST) was reduced to 78% compared to that of raw alum sludge after 5 min of dewatering time. Moreover, the optimal system parameters, including nIC-Conditioner and H2O2 concentrations, as well as the working pH, were optimized, and optimal values were recorded at 1 g/L and 200 mg/L for nIC-Conditioner and H2O2, respectively, with a pH of 6.5. Additionally, scanning electron microscope (SEM) analyses of the sludge prior to and after conditioning were conducted to verify the change in sludge molecules due to this conditioning technique. The results of this study confirm the sustainability of an alum sludge and waste management facility. [ABSTRACT FROM AUTHOR]

Small-sized stainless steel hand files are conventionally employed in root canal treatment procedures for canal scouting and for glide path establishment, owing to their superior flexibility and proficiency in navigating confined spaces. Given the diversity of brands available in the market, there exists potential variability in their physical characteristics, thereby influencing clinical performance. Consequently, this study aims to conduct a comparative analysis of the design, metallurgy, and mechanical characteristics among seven stainless steel hand file brands across ISO sizes 06, 08, and 10. A total of 315 new 25 mm length stainless steel hand files with apical sizes of 0.06, 0.08, and 0.10 from seven distinct brands were included in the study. A meticulous inspection of all instruments was undertaken to identify any structural deformations that might render them ineligible for the study. The design inspection involved the random selection of instruments from each group, which were examined under various microscopes, including a dental operating microscope, optical microscope, and scanning electron microscope. Furthermore, two instruments from each group underwent energy-dispersive X-ray spectroscopy analysis for elemental composition documentation. Mechanical tests were conducted to evaluate the instruments' resistance to lateral deformation (buckling) and their microhardness. Statistical analysis was executed using the nonparametric Mood's median test, with a predetermined significance level of 0.05. Regarding the instruments design, all files exhibited an active blade length ranging from 16 to 17 mm. However, variations were observed in the number of spirals, tip designs, and sizes, with the API K-File notably larger in sizes 0.06 and 0.08 compared to the other instruments. Despite uniform elements composition, differences in geometric features and mechanical properties were evident. Concerning buckling strength, the API K-File demonstrated superior performance across all tested sizes, while the Dentsply ReadySteel, SybronEndo, and Mani K-Files exhibited lower results (p < 0.05). In microhardness assessments, both the API and Oro K-Files displayed the lowest outcomes, with medians of 531 HVN and 532 HVN, respectively, whereas the SybronEndo K-File exhibited the highest microhardness (657 HVN). Despite similar metallurgical composition, the observed distinctions in geometric features and mechanical properties underscore the impact of the manufacturing process on the characteristics of glide path stainless steel endodontic files. These disparities may ultimately influence their clinical performance. [ABSTRACT FROM AUTHOR]

In order to improve the cleanliness of steel, non-aluminum deoxidation processes have begun to replace aluminum deoxidation processes. Although the aluminum deoxidation process can reduce the oxygen content in steel to <10 × 10−6, this deoxidation method causes fatigue failure resulting from the formation of large-grained spherical (Ds-type) inclusions composed of calcium–aluminate. It also tends to lead to nozzle blockage during casting. Given the above problems, this study conducted an in-depth investigation of silicon–manganese deoxidation. Thermal experiments and thermodynamic calculations were used to assess the impact of different Mn–Si ratios on the oxygen content and inclusion characteristics during the deoxidation process of molten steel with different initial oxygen contents. The experimental samples were analyzed using an oxygen–nitrogen–hydrogen analyzer, a direct reading spectrometer, and an automatic scanning electron microscope. After that, the samples were electrolyzed to observe the 2D morphology and 3D morphology of the inclusions using scanning electron microscopy. Finally, thermodynamic calculations were carried out using FactSage to verify the experimental results. The results indicated that, regardless of the initial oxygen content, silicon–manganese deoxidation maintained the total oxygen content at 35 × 10−6. It effectively managed the plasticization of inclusions in molten steel, predominantly yielding spherical silicates while minimizing Al-containing inclusions. Nevertheless, as the initial content of [O] increased, the size and density of the silicate inclusions in the steel also increased. An optimal point in the number and size of inclusions was observed with an increased Mn–Si ratio. Moreover, the combined utilization of silicon–manganese deoxidation, diffusion deoxidation, and vacuum deoxidation enabled ultra-low oxygen content control of molten steel. [ABSTRACT FROM AUTHOR]

Fluoride ions, which interfere with the oxide formation on zirconium have been over-looked until recently. The effect of fluoride ions on oxide formation and dissolution behaviors in zirconium was investigated in this study. A detailed quantitative characterization of the oxide films formed on Zr702 immersed in a fluorinated nitric acid solution was performed using X-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and representative high-angle annular dark-field scanning Transmission Electron Microscope, (TEM). The corrosion performance in a fluorinated nitric acid solution was discussed. The results reveal that the thickness of the oxide films immersed in the fluorinated nitric acid solution was between 42–48 nm, which is much thinner than that of the oxide layer (~98.85 nm thickness) in the F− free HNO3 solution. The oxide film was identified to be a nanocrystalline cluster, comprised of outermost HfO2 and HfF4 layers, sub-outer ZrO2 and ZrF4 layers, and an innermost Zr (F, O)3.6 layer. This fluoride species penetration through the oxide films indicated that the fluoride ions are responsible for the dissolution of the oxide film of Zr702. [ABSTRACT FROM AUTHOR]

In the Al-Fe binary system, the Al13Fe3 phase as well as the Al13Fe4 phase has similar icosahedral building blocks like those appearing in quasicrystals. Therefore, it is of vital importance to clarify the formation process of these two phases. Coexistence of the Al13Fe3 and Al13Fe4 phases was discovered from the educts obtained with a nominal atomic ratio of Al/Fe of 9:2 by high-pressure sintering for the first time. Firstly, single crystal X-ray diffraction (SXRD) combined with a scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) measurement capabilities were adopted to determine the detailed crystal structures of both phases, which were sharply refined with regard to Al13Fe3 and Al13Fe4. Secondly, the orientation relationship between Al13Fe3 and Al13Fe4 was directly deduced from the SXRD datasets and the coexistence structure model was consequently constructed. Finally, seven pairs of parallel atomic planes and their unique orientation relations were determined from the reconstructed reciprocal space precession images. In addition, the real space structure model of the intergrowth crystal along with one kind of interfacial atomic structure were constructed from the determined orientation relations between two phases. [ABSTRACT FROM AUTHOR]

Pure shear tests of textured magnesium AZ31B sheet samples were carried out using a 5 kN Kammrath & Weiss in situ tension-compression stage in a scanning electron microscope in combination with real-time electron backscatter diffraction lattice orientation mapping. The sample design was optimized to produce a pure shear stress in the central gauge zone. Distributions of the deformation twins were correlated with finite element simulations using a linear-elastic constitutive law considering large deformations to show that twins form in areas where the principal compressive stress σ 3 * is a maximum and that they form normal to the trajectories of that minor principal stress. Mappings of the same area at different load values revealed the formation and growth of individual twins and their relationship to the internal elastic strain of individual grains as indicated by the internal grain disorientation. All twins observed were of the extension type, with an 86.3° disorientation with respect to the parent grains. A more detailed study was conducted using transmission electron microscopy to correlate with the EBSD observations and to further elucidate the twin structures within samples. [ABSTRACT FROM AUTHOR]

The collection of twelve bronze artifacts discovered in Xichuan provides invaluable historical insights into the Warring States period (476 BC to 221 BC) of ancient China. To investigate their fabrication techniques and current state of preservation, a comprehensive analysis was conducted using a metallographic microscope, a scanning electron microscope, and an electron spectrometer to examine the microstructure and elemental composition of the artifacts. The findings revealed that the copper content in these bronze artifacts varied between 41.82% and 87.95%, the tin content ranged from 6.79% to 46.88%, and the lead content was less than 28.96%. The microstructure exhibited an α-solid-solution dendritic-crystal-segregation structure, with a substantial amount of (α + δ) eutectic distributed in an island-like pattern. Lead was dispersed unevenly, appearing as small granules and large ellipsoids. The composition of these weapons aligned with their intended use, adhering to the manufacturing standards of traditional Chinese bronzes. However, their state of preservation was suboptimal, necessitating immediate protective measures. This study contributes physical evidence to the research on early Chinese bronze production and offers scientific guidance for the conservation and restoration of these bronze artifacts. [ABSTRACT FROM AUTHOR]

This study investigates the new surface development on AA6061 and AA5086 alloys considering the wire-arc additive manufacturing technique as a direct energy deposition (DED) process of wire. Two different quantities of MWCNTs, i.e., 0.01 (low) and 0.02 (high) g, with a constant nickel (Ni) weight (0.2 g) were pre-placed in the created square patterns. ER4043 filler was used as a wire for additive deposition, and an arc was generated through a tungsten inert gas (TIG) welding source. Furthermore, hardness and pin-on-disk wear-testing methods were employed to measure the changes at the surfaces with the abovementioned inducements. This work was designed to illustrate the hardness and the offered wear resistance in terms of mass loss of the AA6061 and AA5086 aluminum alloys with the function of nano-inducements. Two sliding distance values of 500 m and 600 m were selected for the wear analysis of mass loss from tracks. A maximum increase in hardness for AA6061 and AA5086 alloys was observed in the experiments, with average values of 70.76 HRB and 74.86 HRB, respectively, at a high mass content of MWCNTs. Moreover, the tribological performance of the modified surfaces improved with the addition of MWCNTs with Ni particles in a broader sense; the modified surfaces performed exceptionally well for AA5086 compared to AA6061 with 0.02 and 0.01 g additions, respectively. The system reported a maximum of 38.46% improvement in mass loss for the AA5086 alloy with 0.02 g of MWCNTs. Moreover, the morphological analysis of the developed wear tracks and the mechanism involved was carried out using scanning electron microscope (SEM) images. [ABSTRACT FROM AUTHOR]

Graphene nanoplatelets (GNPs) were synthesized by an electrochemical exfoliation method. Four various conditions of the electrochemical exfoliation process: (I) 1M NaOH with 4V, (II) 0.5M H2SO4 with 5V, (III) a mixture of 1M NaOH and 0.5M H2SO4 with 5V, and (IV) a twostep process of 1M NaOH with 4V and 0.5M H2SO4 with 5V, were compared. The as-synthesized GNPs obtained from all conditions were characterized by Raman spectroscopy and X-ray diffraction. The two-step process provided the GNPs with the low defect concentration and the lowest number of layers. Moreover, confirmed by field emission scanning and transmission electron microscopes (FE-SEM and TEM), the GNPs obtained from the two-step process were multilayer graphene. The GNPs obtained from each condition were added into an ultraviolet-cured acrylate adhesive to fabricate electrically conductive acrylate adhesive (ECAA). The GNPs acted as fillers to play an important role in conducting the electrical network of the ECAA without any other additive. The van der Pauw method was conducted to measure the electrical resistivity of the ECAA. The ECAA, containing 5wt% of the obtained GNPs from the two-step process, had the lowest resistivity when compared to the ECAA which contained the obtained GNPs from other conditions. We found that the percolation threshold of the ECAA, containing the obtained GNPs from the two-step process, was at 3.26 wt%. Last, 6.92 wt% of the GNPs reached the lowest resistivity at 1.09Ω·cm. [ABSTRACT FROM AUTHOR]

Lactarius hatsudake is a common ectomycorrhizal edible mushroom in Pinus massoniana forests, and has important ecological and potential economic values. However, there are only a few reports on the establishment of Pinus massoniana–Lactarius hatsudake symbiosis. Here, we isolated a new strain of L. Lactarius hatsudake (GX01) from a local masson pine forest and established its ectomycorrhizal symbiosis with the P. massoniana. Potato dextrose agar (PDA) medium was optimal for the growth of L. hatsudake GX01. The saffron-to-brown ectomycorrhiza formed by L. hatsudake GX01 are usually bifurcated or coralloid shape, with a rod and a smooth surface, without emanating hyphae. The characteristic mantle and Hartig net structures of ectomycorrhizae were confirmed by microscope and scanning electron microscope (SEM). L. hatsudake GX01 can significantly promote the formation and development of lateral roots of P. massoniana seedlings during the early interaction. This study thus lays the foundation for subsequent study of the symbiotic molecular mechanism and application of P. massoniana–L. hatsudake symbiosis. [ABSTRACT FROM AUTHOR]

Cold rolling emulsion contains a variety of functional additives, which often exhibit complex interactions with each other. Sodium alkane sulfonate (SAS) is a common corrosion inhibitor used in cold rolling emulsions for temporary rust prevention. In this study, it was found that SAS would deteriorate the tribological properties of the emulsion. Emulsions containing SAS and different friction modifiers were prepared. Tribology tests were carried out on a four-ball friction and wear tester. White light interferometer was used to investigate the 3D morphology of the friction surface and wear volume. Microscopic morphology of friction surfaces was observed using a scanning electron microscope (SEM). The chemical activity and electrostatic potential of the molecules were calculated based on density functional theory (DFT). The adsorption energies of additives on metal surfaces were calculated via molecular dynamics (MD) simulation. The results indicate that the strong electrostatic force gives SAS an advantage in competitive adsorption with ester friction modifiers due to the positive charge on the metal surface. This results in the friction modifier not functioning properly and the tribological properties of the emulsion being significantly reduced. [ABSTRACT FROM AUTHOR]

The working device of an excavator in construction machinery is prone to damage and wear under ordinary working conditions. Based on a model of an excavator under typical working conditions, the dynamic load-bearing situation of the three main joint friction subsets of the working device is simulated by using the virtual prototype technology; the location of the functional device with high stress is identified based on finite element analysis, and the correctness of the simulation results is verified by designing strain gauges. Based on this, the dynamic contact stress variation law of the contact surface of the end-face friction subsets was explored, and the end-face wear depth was calculated by combining Archard wear theory and finite element wear simulation technology; the specimens were worn on the end-face wear tester, and the surface wear was observed under the scanning electron microscope to summarize the wear mechanism and analyze the element content changes of the worn surface. The results show that the three main joints of the working device produce large dynamic fluctuations and are prone to wear, and the destructive degree is more prominent; the wear process is accompanied by higher temperatures, fatigue wear, and abrasive wear on the wear surface, and the wear depth value of the right end face is significantly larger than that of the left end face. This method has a significant reference value for reliability analysis and optimization improvement when using construction machinery's main joint friction pairs. [ABSTRACT FROM AUTHOR]

An endophytic symbiont P. aeruginosa-producing anticandidal siderophore was recovered from mangrove leaves for the first time. Production was optimal in a succinate medium supplemented with 0.4% citric acid and 15 µM iron at pH 7 and 35 °C after 60 h of fermentation. UV spectra of the acidic preparation after purification with Amberlite XAD-4 resin gave a peak at 400 nm, while the neutralized form gave a peak at 360 nm. A prominent peak with RP-HPLC was obtained at RT 18.95 min, confirming its homogeneity. It was pH stable at 5.0–9.5 and thermally stable at elevated temperatures, which encourages the possibility of its application in extreme environments. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) against Candida spp. Were in the range of 128 µg/mL and lower. It enhanced the intracellular iron accumulation with 3.2–4.2-fold (as judged by atomic absorption spectrometry) with a subsequent increase in the intracellular antioxidative enzymes SOD and CAT. Furthermore, the malondialdehyde (MDA) concentration due to cellular lipid peroxidation increased to 3.8-fold and 7.3-fold in C. albicans and C. tropicalis, respectively. The scanning electron microscope (SEM) confirmed cellular damage in the form of roughness, malformation, and production of defensive exopolysaccharides and/or proteins after exposure to siderophore. In conclusion, this anticandidal siderophore may be a promising biocontrol, nonpolluting agent against waterborne pathogens and pathogens of the skin. It indirectly kills Candida spp. by ferroptosis and mediation of hyperaccumulation of iron rather than directly attacking the cell targets, which triggers the activation of antioxidative enzymes. [ABSTRACT FROM AUTHOR]

Second-life applications for lithium-ion batteries offer industry opportunities to defer recycling costs, enhance economic value, and reduce environmental impacts. However, cells are affected by numerous aging phenomena which can lead to an acceleration in capacity loss. This paper uses postmortem techniques to compare aging phenomenon in 1.1 Ah 18650 graphite/LFP cells, examining the differences between a pristine cell and three cells aged to 40~30% of state of health (SoH). Macroscopic and microscopic techniques are used to identify aging phenomenon occurring in the cell on both positive and negative electrodes. Energy-dispersive X-ray spectroscopy (EDXS) and scanning electron microscopes (SEMs) with back-scattered electron (BSE) detector are used to analyze each electrode. These methods are used to analyze the morphology and the material on each electrode. The results show a stable positive LFP electrode whereas numerous deposits and cracking occurred on the negative electrode. A discussion of the appearance of those aging phenomenon is presented. Impacts for industrial cells in second-life applications are finally discussed. [ABSTRACT FROM AUTHOR]

The aim of this article is to reduce the environmental harm caused by industrial solid waste, specifically tannery sludge, and enable its reutilization. This study prepared an alkali-activated tannery sludge–slag solidification product (ATSSP) with high mechanical properties using blast furnace slag and tannery sludge as raw materials. The response surface methodology (RSM) was used to optimize the product mix ratio. The hydration mechanism and solidification method of ATSSP for Cr in tannery sludge were studied using X-ray diffraction (XRD), scanning electron microscope-energy dispersive spectrometer (SEM-EDS), and Fourier transform infrared reflection (FT-IR). The results indicate that the compressive strength regression model established through RSM has high accuracy and credibility. When the ratio of activator to binder is 0.2174, the alkali activation modulus is 1.02, and the water-to-cement ratio is 0.37; the 28 d compressive strength of ATSSP can reach 71.3 MPa. The sulfate in tannery sludge can promote the secondary hydration reaction of slag, and the generated hydrated calcium silicate and calcite greatly improve the strength of the ATSSP. The reducing substances contained in slag can reduce Cr (VI) in tannery sludge to Cr (III) in the form of uvarovite. The total Cr and Cr (VI) precipitation concentrations of the product are far less than the specification requirements. [ABSTRACT FROM AUTHOR]

As an environmentally friendly construction material, recycled rubber concrete (RRC) is commonly used as a road material owing to its excellent flexural strength and crack resistance. Previous studies have shown that the addition of fibres is an effective method for improving the crack resistance of concrete. The purpose of this study is to investigate the fracture performance of RRC reinforced with steel fibres (SFs) and glass fibres (GFs). A total of 28 RRC mixtures were prepared. The results of the fracture test showed that the addition of SFs and GFs significantly enhanced the RRC fracture performance. The maximum increases or decreases in flexural strength, brittleness coefficient, fracture energy, initial fracture toughness, and unstable fracture toughness were 64.9, −34.6, 775.6, 92.0, and 118.4%, respectively. The ideal GF content is usually in the range of 0.4–0.6% and decreases with increasing SF content. In addition, scanning electron microscope (SEM) tests were conducted to explore the mechanism of the effect of hybrid fibres on RRC at a microscopic level. The results show that SFs were always pulled out, while GFs were pulled apart at the initial defects. At the same time, excessive GFs caused more initial defects. These results are expected to provide theoretical direction and experimental support for the practical application of hybrid fibre-reinforced recycled rubber concrete (HFRRRC). [ABSTRACT FROM AUTHOR]

This study's novel 13Ni400 maraging steel parts are additively manufactured through a selective laser melting process. The Taguchi approach is adopted to evaluate the combined influence of process variables (energy density), viz., laser power, layer thickness, hatch spacing, and scan speed, on responses like relative density, microhardness, surface roughness, and tensile strength. The powder and material characterization studies are conducted in terms of an optical microscope, scanning electron microscope (SEM), electron backscatter diffraction (EBSD), X-ray diffraction (XRD), and fractography analysis to explore the pre- and post-fabrication scenarios of the build parts. The consequences of energy density and process variables are studied through meticulous parametric studies. Finally, the optimum level of built parameters is identified and validated by a confirmative test predicting an average error of ~1.80%. This work is proficient in producing defect-free parts with maximum densification and improved mechanical properties for newly developed 13Ni-400 maraging steel by the selective laser melting (SLM) technique. [ABSTRACT FROM AUTHOR]

Partial discharge (PD) has a well-established relationship with the lifespan of power cables. This paper has been treated the polyvinyl chloride (PVC) with specified nanoparticles for enhancing dielectric degradation and reducing partial discharge current to extending lifespan of power cables. It has been succeeded to creation new polyvinyl chloride nanocomposites that have been synthesized experimentally via using solution-gel (SOL-GEL) technique and have high featured electric and dielectric properties. The validation of nanoparticles penetration inside polyvinyl chloride during synthesis process have been constructed and tested via scanning electron microscope (SEM) images. The partial discharge current mechanisms in polyvinyl chloride nanocomposites have also been simulated in this work by using MATLAB® software. This paper has explored the characterization of partial discharge current for variant void patterns (air, water, rubber impurity) in polyvinyl chloride nanocomposites insulations of power cables to clarify the benefit of filling different nanoparticles (Clay, MgO, ZnO, and BaTiO3) with varied patterns inside power cables dielectrics. A comparative study has been done for different partial discharges patterns to propose characterization of partial discharges using nanoparticles of appropriate types and concentrations. [ABSTRACT FROM AUTHOR]

Clay soils are rock‐decomposed materials comprised of both clay‐ and non‐clay‐like minerals. Clays' physiochemical and mineralogical composition determines their applicability use in cosmetics. Because of their high bioburden, they must be effectively characterized before being incorporated into cosmetics. The scope of the current study was to characterize two different samples of red and white clays for their physical, chemical and biological properties; mined from Durban, South Africa. Characterization was performed using techniques like X‐ray fluorescence, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscope, hydrogen potential, soil colour, oil absorption, swelling capacity, texture, bulk density, plastic and apparent viscosity, sun protection factor and microbiological analysis. [ABSTRACT FROM AUTHOR]

The paper discusses the characteristics of an oxidising catalytic converter for a diesel engine's particulate filter system, analyzed through simulation and empirical studies. Constructed from a metal monolith, the converter has a 1.4 dm3 volume, 400 cpsi channel density, and a 2.5 g/dm3 platinum coating. Its chemical composition was examined using a scanning electron microscope, revealing platinum crystallites on a highly porous surface. Simulation tests in the AVL Boost program, utilizing real exhaust gas concentration data, assessed the converter's efficiency in converting CO, HC, and NO2 in NOX at various engine speeds and channel conditions. An experiment on an engine dynamometer paralleled these simulations, verifying their accuracy. The study indicates that the simulation algorithm can predict the converter's performance, potentially reducing the need for extensive empirical testing and aiding in preliminary evaluations. [ABSTRACT FROM AUTHOR]

Thin-walled Al-Mg-Si alloy profiles with different compositions and aging states were prepared using the heating and extrusion process. The properties and structure of the profiles were then investigated using a metallographic microscope, scanning electron microscope, projection electron microscope, and universal testing machine. The results show that the yield strength and tensile strength of the profile increases with the increase in total Mg + Si content, and ductility is reduced. If the total Mg + Si content is too high or too low, the crush performance of the material would decrease. Compared with the under-aged and near-peak-aged states, the three types of AI-Mg-Si alloy thin-walled profiles at the over-aged state have better effective energy absorption during crushing and higher bending angle; however, the tensile strength of the profile is optimal at the near-peak-aged state. The effects of alloy composition and aging process on material strength and crushing energy absorption are mainly attributed to the grain structure and differences in precipitation. For coarse grain structures, the grain boundary precipitate free zones are wider, which decreases the profile ductility. Simultaneously, an increase in primary strengthening phases in the grains would increase the profile strength. [ABSTRACT FROM AUTHOR]

Micron‐sized graphite particles additions to Al2011 alloy were investigated to know their impact on mechanical properties. The stir cast method was used to manufacture the Al2011 alloy with 2 and 4 wt% of graphite particles reinforced composites. The microstructural analysis and mechanical properties of the synthesized composites were tested. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) spectrums were used to characterize the microstructure of the samples that were obtained from the casting. SEM micrographs indicated the homogeneous distribution of particles and the EDS patterns confirmed the presence of graphite particles. Al2011 alloy hardness was decreased with the addition of graphite particles. Further, with the addition of 2 and 4 wt% of graphite particles in the Al2011 alloy, the ultimate tensile and yield strengths of composites were increased with increase in elongation. SEM micrographs of tensile fractured surfaces were used to study the various fractured behaviors in the Al2011 alloy‐graphite composites. [ABSTRACT FROM AUTHOR]

Purpose: To compare the fracture resistance and failure modes of anterior cantilever resin‐bonded fixed partial dentures (RBFPDs) fabricated from high translucency zirconia with different intaglio surface treatments. Materials and methods: Sound‐extracted canines (N = 50) were randomly divided into five groups (n = 10) to be restored with high translucency zirconia RBFBDs of different intaglio surface treatments. The RBFPD was designed using exocad software and fabricated using a CAM milling machine. The RBFPDs were treated differently: abrasion with 50 µm alumina particles (Group 1); abrasion with 30 µm silica‐coated alumina particles (Group 2); abrasion with silica‐coated alumina particles (30 µm) and silane application (Group 3); abrasion with silica‐coated alumina particles (30 µm) and 10‐methacryloyloxydecyl dihydrogen phosphate (10‐MDP) primer application (Group 4); abrasion with silica‐coated alumina particles (30 µm) and silane, and 10‐MDP primer application. All RBFPDs were cemented using dual‐cured resin cement. The RBFPDs underwent 6000 thermal cycles with distilled water at 5/55°C for 2 min per cycle and then mechanical cyclic loading with 1200,000 cycles of 50 N at a 1.7 Hz frequency at an angle of 135° to the abutment's long axis. Then, RBFPDs were loaded to fracture using a universal testing machine at 1 mm/min. Maximum fracture forces and failure modes were recorded. Fractured specimens and uncemented specimens were examined using a scanning electron microscope. Data was analyzed using ANOVA and Games–Howell post hoc tests at p < 0.05. Results: Mean fracture load results showed a statistically significant difference between the research groups (p < 0.0001) and it ranged from 69.78 to 584 N. Group 4 exhibited the highest fracture load mean (p < 0.0001) which was significantly different from all other groups. Group 2 recorded a significantly higher fracture load mean than Group 3 (p = 0.029). Three modes of failure were observed: prosthesis debonding, prosthesis fracture, and abutment fracture. Conclusions: Abrasion of zirconia surface with 30 µm silica‐coated alumina particles and application of 10‐MDP primer yielded the highest mean fracture loads of monolithic high translucency zirconia RBFPD. The mode of fracture of the RBFPDs was influenced by the type of surface treatments. [ABSTRACT FROM AUTHOR]

This study is to examine the effect of graphene oxide (GO) and GO‐based nanocomposites (GO_EDTA, GO_CHIT) on the smear layer by scanning electron microscopy (SEM). Sixty human single‐rooted anterior teeth were used. Samples were randomly categorised into six groups. Distilled water in group 1, 17% EDTA in group 2, chitosan (CHIT) solution in group 3, GO solution in group 4, GO_EDTA solution in group 5 and GO_CHIT in group 6 were used as irrigation solutions. Photomicrographs were acquired from the coronal, middle and apical parts of the samples by SEM. Statistical analyses were performed using Kruskal‐Wallis, Mann–Whitney U and Wilcoxon tests. There was a statistically significant difference among the groups (p < 0.003). Adding GO to CHIT and EDTA did not affect removing the smear layer in all segments (p < 0.003). Incorporating GO into EDTA and CHIT solutions did not change their interaction with the smear layer. [ABSTRACT FROM AUTHOR]

The growth of the laundry business increases every year along with population growth, however the laundry waste produced is generally thrown straight into the drain and flows into water bodies without prior treatment. The threshold limits for laundry wastewater quality standards for phosphate content, chemical oxygen demand (COD) and total suspended solid (TSS) are 10 mg/L, 250 mg/L and 100 mg/L respectively based on East Java Governor Regulation No. 72 of 2013. Disposing of laundry waste directly in large quantities into water bodies can have negative effects on the ecosystem in water bodies and water pollution problems. This research aims to determine the efficiency of using GAC and zeolite adsorbents in reducing phosphate, COD and TSS levels in laundry liquid waste. Based on the impact that can pollute water bodies, it is necessary to process laundry liquid waste. One of the processing methods used is the adsorption method, the adsorption process is carried out using granular activated carbon (GAC) and zeolite with a batch system. This research uses liquid wastewater samples from laundry businesses. The variations used in this research are the adsorbent mass, and contact time. The results obtained from this research include Scanning Electron Microscope test results and the percentage reduction in phosphate, COD and TSS levels using GAC and zeolite adsorbents in batch systems. The research results show that the optimum adsorbent mass is 12 grams of adsorbent mixed with GAC and zeolite with a contact time of 150 minutes with a percentage reduction in phosphate levels of 57.14%, a percentage reduction in COD levels of 63.11% and a percentage reduction in TSS levels of 53.11%. The phosphate, COD and TSS values of laundry liquid waste after processing with adsorbent mass, adsorbent composition and optimum contact time are 6.5 mg/L and 383.5 mg/L and 84.5 mg/L. [ABSTRACT FROM AUTHOR]

Nanostructured silicon anodes have shown extraordinary lithium storage properties for lithium-ion batteries (LIBs) but are usually achieved at low areal loadings (< 1.5 mg·cm−2) with low areal capacity. Sustaining sound electrochemical performance at high loading requires proportionally higher ion/electron currents and robust structural stability in the thicker electrode. Herein, we report a three-dimensional (3D) printed silicon-graphene-carbon nanotube (3D-Si/G/C) electrode for simultaneously achieving ultrahigh areal/gravimetric capacities at high mass loading. The periodically arranged vertical channels and hierarchically porous filaments facilitate sufficient electrolyte infiltration and rapid ion diffusion, and the carbonaceous network provides excellent electron transport properties and mechanical integrity, thus endowing the printed 3D-Si/G/C electrode with fast electrochemical reaction kinetics and reversibility at high mass loading. Consequently, the 3D-Si/G/C with high areal mass loading of 12.9 mg·cm−2 exhibits excellent areal capacity of 12.8 mAh·cm−2 and specific capacity of 1007 mAh·g−1, respectively. In-situ optical microscope and ex-situ scanning electron microscope (SEM) confirm that the hierarchically porous filaments with interconnected carbon skeletons effectively suppress the volume change of silicon and maintain stable micro-lattice architecture. A 3D printed 3D-Si/G/C-1∥3D-LiFePO4/G full cell holds excellent cyclic stability (capacity retention rate of 78% after 50 cycles) with an initial Coulombic efficiency (ICE) of 96%. This work validates the feasibility of 3D printing on constructing high mass loading silicon anode for practical high energy-density LIBs. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to show how modified benzoxazine resin/ethylene–propylene–diene monomer rubber/Kevlar composites are prepared. The compatibilization of polar benzoxazine resin and non‐polar EPDM was carried out by EPDM‐g‐MAH copolymer synthesized as a compatibilizer, and then, the microwave (MW) irradiation method and conventional thermal cure (CV) were used to cure this composite. The samples cured by both methods were evaluated and compared by differential scanning calorimetry analysis (DSC), dynamic mechanical thermal analysis (DMTA), scanning electron microscope (SEM), and thermo‐gravimetric analysis (TGA). Microwave curing significantly reduced the curing time, and the composites cured with MW irradiation had higher glass transition temperature (Tg), more uniform curing, higher cross‐link density, and more thermal stability than CV‐cured composites. Highlights: Constructing BZ/EPDM/Kevlar thermal composite for use at high temperatures.Using modified resin to reduce curing temperature and improve final properties.Creating compatibility between non‐polar EPDM rubber and polar BZ resin.Investigating and comparing between thermal and MW curing of the composites. [ABSTRACT FROM AUTHOR]

This study focuses on the surface modification of substrates using a poly(N,N‐dimethyl‐N‐(ethoxycarbonylmethyl)‐N‐[2′‐(methacryloyloxy) ethyl]‐ammonium chloride‐co‐3‐(trimethoxysilyl)propylmethacrylate) P(CBMAE‐co‐TMSPMA) and ethyl orthosilicate (TEOS). By covalently bonding the Si‐OH pendant of the copolymer with hydroxyl residues on the material's surface, a stable polymer coating is formed. The properties of P(CBMAE‐co‐TMSPMA) coatings were evaluated using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscope (SEM), and contact angle (CA) meter. The addition of TEOS allows for the regulation of surface roughness. With the increase of TEOS content, the contact angle of underwater oil first increased and then decreased. The water contact angles were 8°, the underwater superoleophobic contact angle reached 168°, and the number of adherent platelets and Escherichia coli were significantly reduced to 7.5% and 5% on the surface of the coating, respectively. After undergoing simultaneous hydrolysis, the superoleophobic contact angle of P(CBMAE‐co‐TMSPMA)/SiO2 coating further increased to 174°. These interesting and robust properties make them promising candidates for biomedical applications. Highlights: The underwater superoleophobic coating (contact angles of 174°).The P(CBMAE‐co‐TMSPMA)/SiO2 coating with excellent resistance to oil adhesion.Solve the hydroxyl residue problem.The coating resistance to E. coli and platelet adhesion. [ABSTRACT FROM AUTHOR]

In the current study, the effect of cerium content in the steel on the interfacial reaction between the steel and the MgO–C refractory was investigated in laboratory experiments by immersing MgO–C refractory bars into the molten steel. The morphology and chemical composition of reaction products at the interface and inclusions in the steel were analyzed using a scanning electron microscope (SEM) as well as an energy dispersive spectrum (EDS). When there was no cerium in the steel, the reaction product at the steel-refractory interface was mainly MgO due to the reaction between the magnesium vapor and CO at the interface. When the addition content of cerium was 0.02 and 0.1 wt pct, a Ce2O2S layer was generated at the interface by the reaction between the dissolved sulfur and cerium and the MgO refractory. With 0.5 wt pct cerium in the steel, the dissolved sulfur was mostly consumed to form CeS and Ce2O2S inclusions, leading to the generation of a double-layer reaction product of CeAlO3 and Ce2O3 at the interface, and the CeAlO3 was in the refractory side while the Ce2O3 was in the molten steel side. As the content of cerium in the molten steel increased, the erosion of the MgO–C refractory by the steel significantly increased, causing more foreign inclusions into the steel. The consumption of cerium by the steel-refractory reaction led to a significant variation in the composition of cerium-bearing inclusions. Thermodynamic calculation was consistent with the experimental result. [ABSTRACT FROM AUTHOR]

To investigate the degradation effect of bovine trypsin on multispecies biofilm of caries-related bacteria and provide an experimental foundation for the prevention of dental caries. Standard strains of S. mutans, S. sanguis, S. gordonii, and L. acidophilus were co-cultured to form 24 h, 48 h, and 72 h biofilms. The experimental groups were treated with bovine trypsin for 30 s, 1 min, and 3 min. Morphological observation and quantitative analysis of extracellular polymeric substances (EPS), live bacteria, and dead bacteria were conducted using the confocal laser scanning microscope (CLSM). The morphological changes of EPS and bacteria were also observed using a scanning electron microscope (SEM). When biofilm was treated for 1 min, the minimal inhibitory concentration (MIC) of bovine trypsin to reduce EPS was 0.5 mg/mL in 24 h and 48 h biofilms, and the MIC of bovine trypsin was 2.5 mg/mL in 72 h biofilms (P < 0.05). When biofilm was treated for 3 min, the MIC of bovine trypsin to reduce EPS was 0.25 mg/mL in 24 h and 48 h biofilms, the MIC of bovine trypsin was 1 mg/mL in 72 h biofilm (P < 0.05). The ratio of live-to-dead bacteria in the treatment group was significantly lower than blank group in 24 h, 48 h, and 72 h multispecies biofilms (P < 0.05). Bovine trypsin can destroy multispecies biofilm structure, disperse biofilm and bacteria flora, and reduce the EPS and bacterial biomass in vitro, which are positively correlated with the application time and concentration. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Low-density polyethylene is one of the dominant recalcitrant plastic pollutants in the ocean, thus causing complicated problems. Biodegradation is an efficient, environmentally friendly, and sustainable option to overcome these problems. This study aims to quantitatively and qualitatively analyze the ability of marine bacterial isolates to degrade lowdensity polyethylene plastic. METHODS: Bacteria were isolated from plastic samples using serial dilution technique and inoculated on media containing low-density polyethylene powder. Bacterial degradation ability was analyzed quantitatively based on weight loss percentage and energy-dispersive X-ray spectroscopy values, as well as qualitatively based on changes in physical and chemical structures using Scanning Electron Microscopy and Fourier transform infrared spectroscopy. Meanwhile, bacterial isolates were identified based on gene sequence and phylogenetic analyses. FINDINGS: Four bacterial isolates were isolated from low-density polyethylene plastic samples. Quantitative analysis found that the low-density polyethylene film experienced weight loss up to 10-15 percent during 35 days of incubation, with a maximum daily weight loss rate of 0.004 milligrams per day, meaning that the four bacterial isolates have the potential to degrade plastic. Meanwhile, qualitative analysis based on Scanning Electron Microscope observations revealed changes in the physical structure of the film surface in the form of a rough surface, formation of holes, and breakdown into clumps across the film surface. Variations in these changes were tested. In the control, no changes occurred and the film surface remained flat and smooth. Conversely, the results of the energy dispersive X-ray spectroscopy spectrum analysis showed that the lowdensity polyethylene film broke down into smaller fragments, characterized by a decrease in mass from 98.51 percent to 98.23 percent. Fourier transform infrared observations showed variations in transmittance and wavenumbers, indicating changes in chemical bonds or functional groups in the low-density polyethylene film which caused it to become brittle and break down into smaller fragments with a lower molecular weight, making it easier for bacteria to digest. The results of the gene sequence analysis identified four bacterial isolates, namely Lysinibacillus sp. IBP-1, Bacillus sp. IBP-2, Bacillus paramycoides IBP-3, and Bacillus cereus IBP-4. Based on the quantitative and qualitative analyses, the ability of the bacterial isolates to degrade low-density polyethylene film was shown in the following order: Bacillus paramycoides IBP-3 > Bacillus cereus IBP-4 > Lysinibacillus sp. IBP-1 > Bacillus sp. IBP-2. CONCLUSION: All four marine bacterial isolates can use low-density polyethylene as the sole carbon source. Based on quantitative and qualitative analyses, Bacillus paramycoides IBP-3 has the best potential for degrading low-density polyethylene film. This study provides information on potential bacterial isolates that can be developed to control low-density polyethylene plastic waste. [ABSTRACT FROM AUTHOR]

Biodegradation rates and mechanical properties of poly(3-hydroxybutyrate) (PHB) composites with green algae and cyanobacteria were investigated for the first time. To the authors knowledge, the addition of microbial biomass led to the biggest observed effect on biodegradation so far. The composites with microbial biomass showed an acceleration of the biodegradation rate and a higher cumulative biodegradation within 132 days compared to PHB or the biomass alone. In order to determine the causes for the faster biodegradation, the molecular weight, the crystallinity, the water uptake, the microbial biomass composition and scanning electron microscope images were assessed. The molecular weight of the PHB in the composites was lower than that of pure PHB while the crystallinity and microbial biomass composition were the same for all samples. A direct correlation of water uptake and crystallinity with biodegradation rate could not be observed. While the degradation of molecular weight of PHB during sample preparation contributed to the improvement of biodegradation, the main reason was attributed to biostimulation by the added biomass. The resulting enhancement of the biodegradation rate appears to be unique in the field of polymer biodegradation. The tensile strength was lowered, elongation at break remained constant and Young's modulus was increased compared to pure PHB. [ABSTRACT FROM AUTHOR]

Sintered foils are currently being considered as a promising material for anode foils in capacitors due to their high specific capacitance and anti-buckling performance, which meet the requirements for capacitor winding. In this article, sintered foils with added starch were produced using a protective atmosphere sintering process. The effect of starch addition in the range of 0–50 vol% on the specific capacitance and anti-buckling performance of the sintered foils was evaluated. Scanning electron microscope (SEM) analysis confirmed the formation of the pores in the sintered foils due to the addition of starch. These pores play a crucial role in improving the specific capacitance and enhancing the anti-buckling performance of the sintered foils. However, excessive amounts of starch can have a negative impact on the specific capacitance of the sintered foils which initially decreased, then increased, and finally decreased with increasing starch content. On the other hand, the anti-buckling performance increased with increasing starch content. At 30 vol% starch addition, a high specific capacitance of 0.886 μF/cm2 and an anti-buckling performance of more than 120 times were obtained, meeting the requirements for anode foils in aluminum electrolytic capacitors. The specific capacitance of the sintered foils was predicted using the close-packed packing model, which can help establish a powder metallurgy method for preparing anode foil materials with high specific capacitance and anti-buckling performance for aluminum electrolytic capacitors. [ABSTRACT FROM AUTHOR]

Cadmium ion Cd2+ contamination is a major environmental issue caused by industry. Polyarylidene N-hexane pyrrole (PAPh) and crosslinked polyarylidene N-phenyl pyrrole (PAPD) were prepared from the previously synthesized polymer (polyarylidene ketone (PAK)) by using the advantage of repeating carbonyl groups at the 1,4 position and reacting it with hexylamine and P-phenylenediamine via the Paal–Knorr reaction. Various methods were used to characterize polymers, such as FT-IR spectroscopy, X-ray diffraction (XRD), thermogravimetry analysis (TGA), UV–visible spectroscopy, scanning electron microscope (SEM), zeta potential, and surface area measurements (BET), revealing successful fabrication, good thermostability, and well-defined microporous structures useful for Cd2+ adsorption. Optimal adsorption capacities of 55.8 mg g−1 for PAPh and 86.95 mg g−1 for PAPD indicate a significant enhancement in Cd2+ adsorption via their microporous structures, Cd2+ adsorption was also investigated in terms of contact time, initial concentration, and pH. A total input concentration of 30 ppm Cd ions, may yield an 84.3% removal rate for PAPh and an 89.2% removal rate for PAPD. The experimental results were well-fit by many models, including pseudo-second-order kinetics (PSO), Freundlich isotherms, intraparticle diffusion, and Langmuir. The varying adsorption performances of the two polymers studied, (PAPh) and (PAPD), were found to be derived from their respective chemical structures, which include various functional groups, according to studies conducted on Cd2+ in an aqueous solution. Cd2+ adsorption on polymers was considered physisorption; π–cation interactions and surface complexation played significant roles in adsorption. The PAP polymers may be considered promising substitutes and innovative adsorbents to remove Cd2+ ions from a water solution. [ABSTRACT FROM AUTHOR]