Surface Chemical Composition Research Articles

Caracterização de nanopartículas de ferrita de cobalto e avaliação de seu efeito tóxico em camundongos experimentais

This study investigated the characterization of cobalt ferrite nanoparticles (CoFe2O4) prepared by the pulsed laser deposition (PLD) method, using various techniques such as energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and in vitro drug release test (IVRT). It also evaluated the toxicity of these nanoparticles on liver, spleen, heart, and kidney tissues using a mouse model. CoFe2O4 nanoparticles were synthesized from an aqueous solution containing 1mg of CoFe2O4 powder dissolved in DMSO and RPMI serum-free media. XRD analysis revealed the characteristic peaks of the spinel lattice of cubic-shaped cobalt ferrite nanocrystals, with an average crystallite size of 12 nm calculated using Scherrer’s formula. SEM and EDX were used to study the surface morphology and chemical compositions, respectively. The in vivo experiments determined the LD50 of CoFe2O4 to be 3000 mg/kg body weight. Administration of CoFe2O4 nanoparticles at a dosage of 75 mg/kg body weight for 14 days did not cause any changes to the histological structure of the tissues in the mouse model, indicating their potential biocompatibility.

Development of Microstructure on Titanium Implant Surface Using CO2 Laser Processing

Background: Dental biomaterials made of titanium are commonly used. It depends on the implant surface texture to improve fixation and prevent the unwanted adhesion of bone cells. This study aimed to investigate whether continuous laser beam carbon dioxide (CNC - CO2) lasers produce specific textures on titanium surfaces with micrometer-sized indentations that influence cell behavior. Materials and method: (CNC - CO2) red laser device; with a fundamental wavelength of λ=10600 nm and power pulses of 34 W were applied, and textures on the surface of titanium discs were achieved. Results: Excellent degrees of uniformity and repeatability were achieved for the desired portions of the surface by creating different surface textures. The surface topography and chemical composition of the specimens were investigated by scanning electron microscopy, electron dispersive spectroscopy, X-ray diffraction, and surface roughness measurements. Also, a laser power of 34 watts raised the surface roughness, Ra (1.71 nm), and Rz (1.99 nm). Conclusion: Titanium surface textures with unique qualities can be formed in response to an increased heat input. When excessive laser power was used, the measured roughness increased because of instantaneous re-melting. The use of a right continuous-wave (CNC - CO2) laser on titanium used in dental implants can form specific surface textures.

Effect of radiotherapy, immediate dentin sealing and irrigation simulating single- or two-visits endodontic treatment on the bond strength to pulp chamber dentin: an in vitro study.

This study aimed to evaluate the influence of radiotherapy and different endodontic treatment protocols on the bond strength to pulp chamber dentin. Eighty mandibular molars were randomly divided into two groups (n = 40): non-irradiated and irradiated (60Gy). The pulp chambers were sectioned, and each group was subdivided (n = 8), according to the endodontic treatment protocol: no treatment (Control); Single-visit; Two-visits; Immediate dentin sealing (IDS) + single-visit; and IDS + two-visits. Each endodontic treatment visit was simulated through irrigation with 2.5% NaOCl, 17% EDTA and distilled water. IDS was performed by actively applying two coats of a universal adhesive to the lateral walls of the pulp chamber. After, the pulp chambers were restored with resin composite and four sticks were obtained for microtensile test. In addition, the dentin of the pulp chamber roof was assessed for surface roughness, chemical composition, and topography after each treatment protocol. Two-way ANOVA, Tukey's post hoc, Mann-Whitney, Kruskal-Wallis and Dunn's post hoc were performed (α = 5%). The treatment protocol affected bond strength (p < 0.05), while the irradiation did not (p > 0.05). The control group presented the highest values (p < 0.05). The single-visit group demonstrated better performance compared to the other groups (p < 0.05), which did not differ from each other (p > 0.05) The use of IDS changed the surface roughness (p < 0.05), chemical composition (p < 0.05) and topography of the dentin. In conclusion, the treatment protocol influenced dentin adhesion, while irradiation did not.

Improving the Corrosion Resistance of Anodized Al 1050 Alloy by Sealing in Cerium-Containing and Mixed Sodium Phosphate Mono Basic and Calcium Nitrate Solutions

This investigation presents results on the improvement of the corrosion-protective effect of consecutive sealing treatments of anodized Al 1050 (AlAnod). The treatments were performed in cerium-containing and mixed NaH2PO4 + Ca(NO3)2 solutions. The changes of the surface morphology, structure and chemical composition, chemical state of the elements, and basic corrosion parameters of the studied systems were investigated by SEM, EDXS, XRD, XPS, and a complex of electrochemical techniques (PDP, EOCP vs. timeplot, chronoamperometric transients, Rp and CR at EOCP, etc.). The results obtained show that the basic components of the obtained sealing conversion layers (before and after exposure to model Cl−-containing corrosion media) are characterized by Ca10(PO4)6(OH)2, AlO(OH), CePO4, and CeAlO3 (after the corrosion tests, they are converted to insoluble Me-PO3 and Me-P4O10). We conclude that the observed decrease in the corrosion rate of Al and the corresponding increase in the polarization resistance are accomplished by the two-step sealing treatment, which fills up the AlAnod pores with insoluble deposits.

Modulating the corrosion performance of magnesium alloys through hydroxyapatite coating

Magnesium and its alloys have attracted attention as medical bone implant materials due to their excellent biocompatibility, bone-like mechanical properties, and degradability. However, the clinical application of magnesium is limited by the fact that it corrodes too quickly in body fluids, leading to premature mechanical failure. Surface hydroxyapatite coatings can significantly reduce the initial corrosion of magnesium alloys, but suffer from the problems of non-dense coatings, many defects and poor adhesion strength to the substrate. In this study, we propose femtosecond laser construction of microemulsion cone structures on the surface of magnesium alloys to significantly enhance the densities and thicknesses of the coatings, as well as to improve the bonding strength of the coatings to the substrate, which ultimately reduces the corrosion rate. The corrosion rate of modified hydroxyapatite coating in simulated body fluid is only 0.146 mm/y, and it has the ability to rapidly induce hydroxyapatite mineralization and promote osteoblast proliferation. Furthermore, the surface morphology, chemical composition, and wettability of the laser-modified Mg alloy were analyzed. It was demonstrated that the microstructure and thin oxide layer formed on the surface of the magnesium alloy could provide more sites for HA nucleation, which promotes the deposition and growth of HA and the existence of a mechanical interlocking effect with the substrate. The application of femtosecond laser surface modification represents a rapid and efficacious approach to enhance the quality of hydroxyapatite coatings. This method has successfully controlled the corrosion rate of magnesium alloys with excellent biocompatibility, thereby overcoming potential obstacles to the use of magnesium alloys in clinical applications.

Facile and scalable growth of bimetallic 3D Ag/MIL125-NH2 on cotton fabric for multifaceted anti-wetting and self-healing characteristics

Multifunctional cotton fabric holds great promise across domestic and healthcare sectors. However, the challenge lies in developing a simple, sustainable method to create versatile, multifunctional cotton fabric. Herein, we designed novel 3D bimetallic organic frameworks (Ag/MIL125-NH2) for the first time and fabricated BM125@COT, a superhydrophobic cotton fabric adorned with porous hierarchical grooves. This was achieved by spraying Ag/MIL125-NH2 onto the cotton fabric's surface, followed by post-synthetic treatment with non-fluorinated myristic acid, resulting in superhydrophobic BM125@COT. The coated fabric showed a water contact angle (WCA) of 162.2° and a water sliding angle (WSA) of 4° ± 1. Surface morphology, size, structural and chemical composition, and anti-wetting properties of synthesized MOFs and BM125@COT were evaluated by SEM, EDS, TEM, XRD, XPS, UV/Vis, ATR, DSC, and Optical Tensiometer. Durability tests, including splash tests, abrasion resistance, tape peeling, washing, pH effects, and ultrasonication cycles, underscored the fabric's robust mechanical stability and chemical resistance. Moreover, superhydrophobic BM125@COT demonstrated UV-blocking efficiency, impressive self-cleaning capabilities, and enhanced antibacterial activity. This low-cost, scalable, and sustainable fabric, fabricated through a straightforward one-step spray coating technique, holds immense potential for versatile applications.

Improving frictional and insulation performance with silica-coated titanium dioxide additives in grease

PurposeThe purpose of this study was to synthesize composite nanoparticles (TiO2@SiO2) via the chemical deposition method and investigate their efficacy as additives in polytetrafluoroethylene (PTFE) lubricating grease. The focus was on examining the frictional and conductive properties of the TiO2@SiO2 grease using a friction tester.Design/methodology/approachComposite nanoparticles (TiO2@SiO2) were synthesized using the chemical deposition method and incorporated into PTFE grease. Frictional and conductive properties were evaluated using a friction tester. Surface morphology and chemical composition of wear tracks were analyzed using scanning electron microscope and X-ray photoelectron spectroscopy, respectively.FindingsIncorporating TiO2@SiO2 at a mass fraction of 1 Wt.% led to a significant reduction in friction coefficient and wear width. The wear depth exhibited a remarkable decrease of 260%, while the contact resistance reached its peak value. This improvement in tribological properties could be attributed to the presence of TiO2@SiO2, where TiO2 served as the core and SiO2 as the shell during the friction process. The high hardness of the SiO2 shell contributed to enhanced load-bearing capacity. In addition, the exceptional insulation properties of SiO2 demonstrated excellent electron-capturing capabilities, resulting in improved friction and insulation performance of the TiO2@SiO2 lubricating grease.Originality/valueThis study demonstrates the potential of TiO2@SiO2 composite nanoparticles as additives in lubricating greases, offering improved friction and insulation performance. The findings provide insights into the design of advanced lubricating materials with enhanced tribological properties and insulation capacity, contributing to the development of more efficient and durable lubrication systems.

Bergera koenigii stem-derived magnetic biochar nanocomposite for enhanced photocatalytic efficiency of Ce1-xZnxO2-δ NPs under UV light for the degradation of methyl orange

The production of mesoporous, nanocrystalline, Zn-doped CeO2 nanoparticles (NPs) at various concentrations of Zn, Magnetic biochar (MBC)-Zn-doped CeO2 nanocomposites (NC), their characterizations, and photocatalytic degradation analysis are presented in this study. The synthesis of MBC-Ce0.91Zn0.09O2-δ NC is based on the carbonization of an iron oxide precursor with powdered Bergera koenigii stem (curry leaf stem). XRD and TEM results confirm polycrystalline, spherical fluorite Ce1-xZnxO2-δ NPs and MBC-Ce0.91Zn0.09O2-δ NC formations. The crystallite size varies from 4–12 nm with an increase in the doping concentration of Zn and 8.55 nm for MBC-Ce0.91Zn0.09O2-δ NC. XPS analysis displays the valence states and surface chemical composition of the as-prepared MBC-Ce0.91Zn0.09O2-δ sample. BET analysis provides the surface area (17–32 m2/g for Ce1-xZnxO2-δ NPs and 142 m2/g for MBC-Ce0.91Zn0.09O2-δ NC) and pore size (25–45 Å for Ce1-xZnxO2-δ NPs and 17.35 Å for MBC-Ce0.91Zn0.09O2-δ NC) of all the samples. All the samples possess good UV absorption in the range of 200–400 nm, and the bandgap energy of the as-prepared samples decreased from 3.088 to 2.79 eV with increased dopant concentration and on-load magnetic biochar. The oxygen deficiencies and lattice deformations of the as-prepared samples are studied using Raman, FTIR, and photoluminescence (PL) spectra. The degradation efficiency of 5 ppm Methyl Orange (MO) is analyzed using 50 mg catalytic (Ce1-xZnxO2-δ NPs, MBC-Ce0.91Zn0.09O2-δ NC) dosage by maintaining the pH of the solution as 4. After 16 min of UV irradiation, the as-synthesized Ce0.91Zn0.09O2-δ NPs and MBC-Ce0.91Zn0.09O2-δ NC exhibit 91 % and 97 % decolorization and 90 % and 94 % total organic carbon (TOC) removal efficiency. Regression analysis is performed to evaluate each model's applicability to photocatalytic degradation. The regeneration experiments on Ce0.91Zn0.09O2-δ NPs and MBC-Ce0.91Zn0.09O2-δ NC prove the stability of these catalysts for activating MO.

Graphene-coated sand for enhanced water reuse: Impact on water quality and chemicals of emerging concern

This paper investigates the potential of graphene-coated sand (GCS) as an advanced filtration medium for improving water quality and mitigating chemicals of emerging concern (CECs) in treated municipal wastewater, aiming to enhance water reuse. The study utilizes three types of sand (Ottawa, masonry, and concrete) coated with graphene to assess the impact of surface morphology, particle shape, and chemical composition on coating and filtration efficiency. Additionally, sand coated with graphene and activated graphene coated sand were both tested to understand the effect of coating and activation on the filtration process. The materials were characterized using digital microscopy, Raman spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction analysis. The material's efficiency in removing turbidity, nutrients, chemical oxygen demand (COD), bacteria, and specific CECs (Aciclovir, Diatrizoic acid, Levodopa, Miconazole, Carbamazepine, Diphenhydramine, Irbesartan, Lidocaine, Losartan, and Sulfamethoxazole) was studied. Our findings indicate that GCS significantly improves water quality parameters, with notable efficiency in removing turbidity, COD (14.1 % and 69.1 % removal), and bacterial contaminants (64.9 % and 99.9 % removal). The study also highlights the material's capacity to remove challenging CECs like Sulfamethoxazole (up to 80 % removal) and Diphenhydramine (up to 90 % removal), showcasing its potential as a sustainable solution for water reuse applications. This research contributes to the field by providing a comprehensive evaluation of GCS in water treatment, suggesting its potential for removing CECs from treated municipal wastewater.

Novel spherical InVO4/floral Bi2MoO6 Z-scheme heterojunction for efficient photocatalytic carbon dioxide reduction

The development of efficient CO2 reduction photocatalysts is of great significance to improving the global greenhouse effect and alleviating the energy crisis. In this paper, spherical InVO4/floral Bi2MoO6 (IVO/BMO) Z-scheme heterojunction was prepared by a hydrothermal method, and the surface structure, chemical composition, and photovoltaic properties of the samples were characterized and tested for their CO2 reduction performance. The experimental results show that 1.5 %-IVO/BMO exhibits excellent photocatalytic activity for CO2 reduction under the irradiation of 300 W Xenon lamp, with a CO yield of 34.08 µmol/g/h and a CH4 yield of 4.49 µmol/g/h, which are 2.55 and 1.05 times higher than that of the pure Bi2MoO6, respectively. The enhanced photocatalytic activity can be attributed to the formation of an IVO/BMO Z-scheme heterojunction, which promotes electron separation and reduces charge recombination at the interface, facilitating the reaction process. This study provides a novel Z-scheme photocatalyst for efficient carbon dioxide reduction.

Preparation and weathering properties of Ce/TiO2 anti-UV coating on heat-treated wood

Heat-treated wood is widely used as building exterior wall panels and landscape materials due to its excellent dimensional stability and durability. However, heat-treated wood is susceptible to discoloration and cracking due to ultraviolet radiation, temperature and humidity changes in the outdoor environment. In this study, Ce/TiO2 alcohol solution was prepared by sol-gel method, and the inorganic anti-ultraviolet coating was attached to the surface of wood by brush coating. Then artificial accelerated weathering test was carried out for 672 h to evaluate the weathering behavior of heat-treated wood. UV–Vis spectroscopy and macroscopic morphology analysis of the glass substrate show that the coating has good transparency and effective UV shielding ability. Scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analysis showed that the coating successfully adhered to the wood surface and played a good anti-ultraviolet effect. After artificial weathering, the color difference values of unmodified wood, Ce modified wood, TiO2 modified wood and Ce/TiO2 modified wood were 6.04, 4.97, 3.67 and 3.29, respectively. Based on the changes of color and wood chemical composition, the Ce/TiO2 anti-ultraviolet coating can significantly improve the weathering resistance of heat-treated wood, and ultimately limit the degradation degree of surface chemical composition of heat-treated wood.

Fouling and Corrosion Behavior of Nickel–Graphene/Polytetrafluoroethylene Composite Hydrophobic Coating

Fouling and corrosion mitigation in heat exchange equipment remains a significant challenge. Numerous research techniques have been developed to address this issue. Surface modification is an effective method for preventing fouling and corrosion. This work used electrodeposition and dip coating techniques to create a nickel–graphene/polytetrafluoroethylene (NGP) composite hydrophobic coating. The field emission scanning electron microscopy, contact angle analyzer, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and atomic force microscopy techniques were used to investigate the surface morphologies, wettability, binding energies, chemical compositions, and roughness, respectively. The water contact angle (WCA) of the NGP hydrophobic coating (147.1° ± 2.2°) was significantly higher than the WCA of carbon steel (76.8° ± 1.6°). Electrochemical impendence spectroscopy results showed that the NGP composite hydrophobic coating has improved anti-corrosion performance with a greater capacitive curve, a higher modulus of impedance value at low frequency, and increased charge transfer resistance. Furthermore, fouling testing at various temperatures exhibited the anti-fouling and anti-corrosion behavior of the NGP composite hydrophobic coating, suggesting possible uses in practical applications.

Zwitterionic sulfobetaine methacrylate (SBMA) coating on hydrophobic acrylic intraocular lens material to prevent the adhesion of lens epithelial cells: Effect of SBMA concentration

Posterior capsular opacification (PCO), known as a prevalent complication of cataract surgery, occurs because of the attachment and abnormal proliferation of remaining lens epithelial cells (LECs) after cataract surgery. To reduce the PCO occurrence by improving cell adhesion resistance, we attempted zwitterionic sulfobetaine methacrylate (SBMA) coating through ultraviolet-induced graft polymerization on the surfaces of intraocular lens (IOL) materials. In this study, the effect of the concentration of SBMA monomers in the coating solutions adjusted from 10 wt% to 30 wt% was investigated on the chemical composition, morphology, and hydrophilicity of the IOL material surfaces modified with SBMA. Additionally, the effect of SBMA concentration on preventing adhesion to protein and LECs on the surfaces of SBMA-modified IOL materials was evaluated in vitro. Grafting of zwitterionic SBMA on the surfaces of hydrophobic acrylic IOL materials was confirmed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and water contact angle (WCA). To evaluate the long-term hydrophilicity of coating films prepared with different concentrations of SBMA on the IOL material surfaces, the WCA of IOL materials stored in phosphate-buffered saline solution was measured as a function of time. The coating film prepared at a concentration of 20 wt% of SBMA showed the lowest WCA after 28 days, showing the best long-term hydrophilicity. Also, that prepared at a concentration of 20 wt% of SBMA exhibited the highest anti-adhesion effect on proteins and LECs.

Synthesis of Gemini-type imidazoline quaternary ammonium salt using by-product fatty acid as corrosion inhibitor for Q235 steel

Gemini-type imidazoline quaternary ammonium salt is a new type of environmentally friendly corrosion inhibitor has been widely used in engineering materials. However, most of them are hazardous/toxic compounds derived from petroleum-based products, which did harm to environment. In this work, an environmentally friendly Gemini-shaped imidazoline quaternary ammonium salt corrosion inhibitor (G211) was synthesized using cheap fatty acid recycled from dimer acid industry as feedstock. The corrosion inhibition effects of G211 on Q235 steel in 1 M HCl solution were investigated through weight loss experiments, potential polarization curves, and alternating current impedance spectroscopy experiments. The results show that the inhibition rate of G211 as a mixed-type inhibitor is up to 94.4% and the concentration drop as low as 500 ppm at 25 ℃. The adsorption of G211 on Q235 surface follows Langmuir adsorption isothermal curve. The chemical composition of the Q235 steel surface was analyzed through scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Furthermore, the possible corrosion inhibition mechanism of G211 on the surface of Q235 steel is proposed. This article not only presents an outstanding solution for safeguarding Q235 steel against corrosion but also introduces a feasible method for high-value utilization of monomer acid (MA).

EVALUATION OF THE EFFECT OF AIR ON THE HYDRATION SYSTEM OF THE AXIAL PISTONS

This study investigates the effect of air exposure on the hydration system of axial pistons, critical components in various hydraulic systems. The hydration process, which is integral to the functionality and longevity of axial pistons, is potentially sensitive to environmental factors such as air. This research aims to elucidate the effect of air on the hydration kinetics, surface properties and performance of axial pistons. Experimental studies were conducted using controlled environments to analyze the hydration behavior of piston samples under varying degrees of air exposure. Techniques such as surface microscopy, chemical analysis and mechanical testing were used to comprehensively evaluate the effects. Preliminary findings indicate that exposure to air significantly affects the hydration kinetics of axial pistons, affecting the rate and extent of hydration. Surface analysis reveals changes in surface morphology and chemical composition indicating changes in the air-induced hydration process. Moreover, mechanical testing reveals notable differences in the performance characteristics, including wear resistance and friction properties, of pistons exposed to varying weather environments. Overall, this study underlines the importance of considering air exposure in understanding and optimizing the hydration system of axial pistons and provides valuable information for improving hydraulic system efficiency and reliability. Keywords: axial pistons, hydration system, piston, hydraulic machine, rotor.

Dehydration of Organic Solvents from Ternary Mixtures Containing Toluene/Methanol/Water by Pervaporation.

The separation of a toluene/methanol/water ternary mixture is a difficult task due to the toluene/water and toluene/methanol azeotropes. In this article, low-energy pervaporation is proposed for the separation of the ternary azeotrope toluene-methanol-water. This work investigates the effects of feed temperature, feed flow rate, and vacuum on pervaporation and compares the energy consumption of pervaporation with that of distillation. The results showed that at the optimized flow rate of 50 L/h and a permeate side vacuum of 60 kPa at 50 °C, the water and methanol content in the permeate was about 63.2 wt.% and 36.8 wt.%, respectively, the water/ methanol separation factor was 24.04, the permeate flux was 510.7 g/m2·h, the water content in the feed out was reduced from 2.5 wt.% to less than 0.66 wt.%, and the dehydration of toluene methanol could be realized. Without taking into account the energy consumption of pumps and other power equipment, pervaporation requires an energy consumption of 43.53 kW·h to treat 1 ton of raw material, while the energy consumption of distillation to treat 1 ton of raw material is about 261.5 kW·h. Compared to the existing distillation process, the pervaporation process consumes much less energy (about one-sixth of the energy consumption of distillation). There is almost no effect on the surface morphology and chemical composition of the membrane before and after use. The method provides an effective reference for the dehydration of organic solvents from ternary mixtures containing toluene/methanol/water.

A Review of Cellulosic Fibre Surface Modification Techniques - The Case of Ramie

The demand for cellulosic fibres as a reinforcement in polymers is growing due to their renewable, biodegradable, and ecologically favourable properties. In addition, they are lower in density than e.g. glass fibres, which will help in making lightweight composites. Besides, there is no health hazard with ease of processing and minimum damage to the processing equipment. Despite their advantages and high demand, their utilization in industrial applications is still limited. This is due to their inherent polar and hydrophilic nature and their consequent incompatibility with hydrophobic polymers. Therefore, it is often necessary to do hydrophobic modification treatment. The review examines a range of strategies for modifying ramie surfaces, encompassing physical, chemical, and biological processes. It also analyzes the procedures and techniques involved in the preparation and manufacturing of ramie-reinforced polymeric biocomposites. Moreover, an investigation is conducted to evaluate the performance of the composites produced. The performance evaluation includes both before and following fibre treatment, covering surface morphology, wettability, chemical composition, mechanical properties, and flame retardancy. Most of the researchers reported that alkaline and silane coupling agent treatments are the most prevalently applied pretreatments. Compared to biological and physical methods, the application of chemical agents enables excellent adhesion of fibre to polymer resins. However, the utilization of solvents such as ethanol and methanol increases the amount of waste produced and toxic compounds released.

Electrochemical Polishing of Ti and Ti6Al4V Alloy in Non-Aqueous Solution of Sulfuric Acid.

This paper reports the results of our study on electrochemical polishing of titanium and a Ti-based alloy using non-aqueous electrolyte. It was shown that electropolishing ensured the removal of surface defects, thereby providing surface smoothing and decreasing surface roughness. The research was conducted using samples made of titanium and Ti6Al4V alloy, as well as implant system elements: implant analog, multiunit, and healing screw. Electropolishing was carried out under a constant voltage (10-15 V) with a specified current density. The electrolyte used contained methanol and sulfuric acid. The modified surface was subjected to a thorough analysis regarding its surface morphology, chemical composition, and physicochemical properties. Scanning electron microscope images and profilometer tests of roughness confirmed significantly smoother surfaces after electropolishing. The surface profile analysis of processed samples also yielded satisfactory results, showing less imperfections than before modification. The EDX spectra showed that electropolishing does not have significant influence on the chemical composition of the samples.

A novel surgical diamond spherical wheel to prevent bone adhesion with superhydrophobic and super-slippery coatings

Ordinary commercial diamond spherical wheels are extensively used in bone grinding surgeries. However, a persistent issue arises from bone debris adhering to the wheel surface, leading to elevated temperatures during the bone grinding process. To address this, the study developed a novel spherical wheel with a superhydrophobic and super-slippery coating to prevent the bone debris adhesion. Initially, a superhydrophobic and super-slippery coating was successfully designed and fabricated with mixture of ODA-GO, PDMS, KH-550, and epoxy resin E44. The coating's surface morphology, chemical composition, and durability were comprehensively characterized. Subsequently, the coating was applied to diamond spherical grinding wheels for bone grinding experiments. The results demonstrate that a coating with exposed ODA-GO forms a rough structure with optimal component parameters, achieving a contact angle of 158° and a sliding angle of 4.2°. Furthermore, the superhydrophobic and super-slippery coating exhibits exceptional wear and slipperiness resistance even after 100 cycles, maintaining a contact angle of 135° and a sliding angle of 8.5°. The use of this novel spherical wheel significantly mitigates bone debris adhesion. This study not only provides valuable insights into the mechanisms of anti-adhesion but also introduces a promising technique for enhancing the performance of diamond spherical wheels.

A novel photocatalyst of Y2O3-BaO-ZnO ternary system for enhanced photocatalytic degradation of carbofuran insecticide

A novel Y2O3-BaO-ZnO ternary system was synthesized via precipitation of a mixture of Y(NO3)3.6 H2O:Ba(NO3)2:Zn(NO3)2.6 H2O using some Fibonacci sequences. The Y2O3-BaO-ZnO was applied to the photocatalyst to investigate the degradation of carbofuran insecticide. The Y2O3-BaO-ZnO prepared at the sequence ratio of 5:8:13 (YBZ5) exhibited the highest photocatalytic performance. Morphological characterization showed that the particle size of the YBZ5 sample was significantly smaller than that of ZnO by over half, possibly providing high surface areas. The crystalline structure, functional group, and surface chemical composition investigations confirmed the presence of Y2O3, BaO, and ZnO. The fluorescence study exhibited no difference. Based on band gap energy and energy band alignment analysis, the Y2O3-BaO-ZnO ternary system demonstrated a well-aligned valence band. The energy band alignment analysis revealed a good alignment of the valence band for continuous hole transport in the Y2O3-BaO-ZnO ternary system. The alignment induces charge separation which reduces recombination and provides efficient active carriers at the surfaces of the photocatalyst, allowing reactions with toxic molecules. Therefore, the synergistic function of high surface areas and appropriate energy band alignments of the novel Y2O3-BaO-ZnO ternary system is considered the crucial factor in the enhancement of photocatalytic performance.