Metal Surface Research Articles

Design and Development of Dual‐Function Nano‐CeO2‐Integrated PUF/Epoxy Microcapsule Systems for Self‐Healing and Corrosion‐Resistant Epoxy Coatings

ABSTRACTA dual‐function microcapsule system was developed to overcome the limitations of single‐mechanism self‐healing coatings. Nano‐CeO2 particles were embedded in a polyurea formaldehyde (PUF) shell, with epoxy resin encapsulated inside. SEM, FTIR, and XRD characterization confirmed the successful integration of CeO2 and epoxy within the microcapsules. These microcapsules were incorporated into an epoxy resin‐based coating at varying weight percentages to assess their impact on coating performance. EIS was employed to evaluate the self‐healing properties of coatings with artificial scratches in simulated seawater. When the coating is damaged, CeO2 is released and deposited on the metal surface, rapidly forming a passivation film that protects the substrate in advance. CeO2 also releases cerium ions. A cerium hydroxide precipitate is formed by reacting with OH− produced in the cathode region. Prevents penetration of corrosive ions. Meanwhile, the microcapsules rupture, releasing epoxy resin to heal the cracks. Electrochemical Impedance Spectroscopy (EIS) results demonstrated that the optimal self‐repair performance was achieved with 10 wt% microcapsules, while higher concentrations negatively affected the coating's adhesion. This dual‐function microcapsule approach significantly improves both protective and self‐healing capabilities, offering potential for advanced corrosion‐resistant coatings.

Catalytic ignition of deuterium–air mixtures over a metallic rhodium surface at pressures of 1–2 atm

The regularities of catalytic ignition of deuterium–air mixtures above the surface of metallic rhodium at pressures of 1–2 atm and temperatures of 20–250 °C using hyperspectrometers in the range of 400–1650 nm and high-speed filming have been established. It is established that the catalytic ignition of deuterium–air mixtures in the studied temperature range is observed at a deuterium content of more than 12%; and at a deuterium content of less than 12%, only intense heating of the catalytic wire is observed. It is shown that the initial ignition source occurs on the surface of the reactor. In subsequent experiments, under the same conditions, the location of the original center changes. It has been found that the upper limit of the catalytic ignition above the D2–air mixture is noticeably lower than the lower ignition limit of the H2–air mixture. Thus, D2 is more combustible than H2 over the surface of Rh at a pressure above 1 atm. The limits of catalytic ignition are even lower than 20 °C, although the flame velocity in hydrogen–air mixtures and the flame temperature in these mixtures of the same composition are much higher than those of deuterium–air mixtures. The nature of the detected kinetic inverse isotope effect is probably determined by the high level of activity of rhodium deuteride in relation to the deuterium oxidation reaction.

Evaluation of the efficiency of inhibitor protection of metal surfaces in aggressive water and oil environments

The article analyzes the problems associated with the occurrence of corrosion processes of equipment during oil and gas production. The main anti-corrosion methods and means used in modern conditions are considered. In the vast majority of cases, the corrosion of industrial equipment proceeds by an electrochemical mechanism when the metal is in contact with an aqueous mineralized environment, therefore it is advisable to use the inhibitory protection of the equipment against corrosion processes. It is known that corrosion inhibitors are substances, the introduction of which in relatively small quantities into an aggressive environment causes a noticeable slowing down of metal corrosion. In fact, it is a substance that inhibits the corrosion process due to competitive adsorption with particles of activators and the formation of protective adsorption or phase films on the metal surface, sometimes with barrier properties. Corrosion inhibitors affect the kinetics of electrode processes that occur during corrosion, and are also characterized by the ability to form oxide, hydroxide or other films on the metal and transfer the metal to a passive state. Taking into account the mechanism and conditions of corrosion processes during the extraction and transportation of oil-containing products and gas condensate, a chemical method of equipment protection was chosen for research. Known inhibitors based on phosphonic acids, as well as synthesized substances based on sulfonates, imidazolines, and diamines, were used as chemical agents in the research. As a result of the research, the effectiveness of protecting metals from corrosion was evaluated depending on the composition of the highly mineralized environment, the type of metal, the type of inhibitor and its concentration, and the effectiveness of the developed scale stabilizer (sodium nitrile dimethyl sulfonate) was evaluated in comparison with known reagents. It is shown that the effectiveness of protecting metals from corrosion in water-oil mixtures using alkylimidazoline inhibitors and inhibitors developed on the basis of sunflower oil and polyalkylene polyamine (AC-1), ethylenediamine (AC-2) reaches 90% in doses of 5 - 50 mg/dm3.

A springback minimization study using the experimental design methods for 15-5 PH stainless steel material in the hydroforming process

Purpose This study aims to examine the springback behavior of 15-5 PH stainless steel, which is widely used in the aviation industry. Design/methodology/approach The shaping sheet metal with a diaphragm is a widely used shaping method in aviation. In this process, the sheet metal is attached to the mold, placed in the form machine and pressure is applied. The diaphragm, which swells under the influence of gas, transmits pressure to the sheet metal surface and allows the mold to take its shape. One of the behaviors that occurs in the part after processing is springback. The mold design is shaped according to this springing amount. Some prominent parameters in the amount of springback are bending radius, bending angle, material thickness and material type. Material thickness is taken as 0.813, 1.27, 1.6 and 2 mm for experimental studies. This study compares the general full factorial design with the 2k factorial design. Then, the authors get analysis of variance (ANOVA) tables for the experiments and finite element analysis results, respectively. Findings At the end of the study, a mathematical expression was obtained that gives the springback rate with an accuracy of over 90%, depending on the process parameters, in 15-5 PH material. In addition, the main effects of the working parameters on the springback behavior were revealed by ANOVA method. Originality/value To the best of the authors’ knowledge, this is a new application that provides robust results to the springback minimization for the sheet metal bending process.

Simulation of metal nanoparticles growth in methane atmosphere of arc discharge: comparison to experiment

Abstract A direct current arc discharge in a methane atmosphere is a scalable and sustainable method to produce metal-carbon core–shell nanoparticles and single-walled carbon nanotubes, where a metal catalyst can be continuously supplied through evaporation of an anode made from the catalyst material. The size of catalyst particles is of critical importance as it can affect the synthesis yield and properties of nanotubes and core–shell nanoparticles. This study presents a numerical model describing the formation and growth of metal particles for the conditions representative of the arc discharge with an evaporating iron anode at near-atmospheric pressure of a methane-rich atmosphere. The model incorporates carbon adsorption to the metal surface and explains the limiting effect of carbon coverage on the size of metal nanoparticles. The predicted particle sizes are compared with experimental observations. The model also predicts higher concentrations of metal particles with the increasing partial pressure of methane.

Evaluating Communication Performance in Rotating Electrical Machines Using RSSI Measurements and Artificial Intelligence.

This paper introduces a novel methodology for evaluating communication performance in rotating electric machines using Received Signal Strength Indication (RSSI) measurements coupled with artificial intelligence. The proposed approach focuses on assessing the quality of wireless signals in the complex, dynamic environment inside these machines, where factors like reflections, metallic surfaces, and rotational movements can significantly impact communication. RSSI is used as a key parameter to monitor real-time signal behavior, enabling a detailed analysis of communication reliability. The methodology comprises several stages, including data collection, preprocessing, feature extraction, and model training. Various machine learning models are implemented and evaluated. Among these, the SVM model with a Radial Basis Function (RBF) kernel outperforms others, achieving an accuracy of 97%, with high precision and recall scores, confirming its robustness in classifying RSSI data and handling complex signal behavior. The confusion matrix further supports the SVM model's accuracy, showing minimal misclassification.

Synergistic Enhancement of Plasma-Driven Ammonia Synthesis Using a AuCu3/Cu Composite Catalyst.

Green ammonia synthesis using fluctuating renewable energy supply in decentralized process is a goal that has been long sought after. Ammonia synthesis with non-thermal plasma under mild conditions is a promising technology, but it faces the critical challenge of low energy efficiency. Herein, we develop an easily-scalable AuCu3/Cu catalyst, which consists of a decimeter-scale metallic Cu antenna and nano-scale AuCu3 catalytic sites on metallic Cu surface, significantly enhancing the energy efficiency and ammonia yield in a radio-frequency (RF) plasma system. Compared to plasma alone, the single-pass ammonia yield over AuCu3/Cu increases by a factor of 20, approaching 10 %. Mechanistic studies indicate that Cu antenna can amplify the millimeter-scale local electric field, thereby facilitating the generation of active nitrogen species, including nitrogen radicals and vibration-excited nitrogen molecules. Due to the downshifted d-band center and unique Cu-Au interface structure, the AuCu3 nanoalloy modified on Cu antenna surface significantly reduces hydrogenation barriers of active NHX (x=0,1,2) species (the rate-determining step) and facilitates ammonia desorption at lower temperature. The synergistic effect of Cu antenna and surface AuCu3 nanoalloy comprehensively enhances ammonia synthesis through both the nitrogen radical-mediated Eley-Rideal pathway and the vibration-excited nitrogen molecule-mediated Langmuir-Hinshelwood pathway.

Synergistic Enhancement of Plasma‐Driven Ammonia Synthesis Using a AuCu3/Cu Composite Catalyst

Green ammonia synthesis using fluctuating renewable energy supply in decentralized process is a goal that has been long sought after. Ammonia synthesis with non‐thermal plasma under mild conditions is a promising technology, but it faces the critical challenge of low energy efficiency. Herein, we develop an easily‐scalable AuCu3/Cu catalyst, which consists of a decimeter‐scale metallic Cu antenna and nano‐scale AuCu3 catalytic sites on metallic Cu surface, significantly enhancing the energy efficiency and ammonia yield in a radio‐frequency (RF) plasma system. Compared to plasma alone, the single‐pass ammonia yield over AuCu3/Cu increases by a factor of 20, approaching 10%. Mechanistic studies indicate that Cu antenna can amplify the millimeter‐scale local electric field, thereby facilitating the generation of active nitrogen species, including nitrogen radicals and vibration‐excited nitrogen molecules. Due to the downshifted d‐band center and unique Cu‐Au interface structure, the AuCu3 nanoalloy modified on Cu antenna surface significantly reduces hydrogenation barriers of active NHX (x=0,1,2) species (the rate‐determining step) and facilitates ammonia desorption at lower temperature. The synergistic effect of Cu antenna and surface AuCu3 nanoalloy comprehensively enhances ammonia synthesis through both the nitrogen radical‐mediated Eley‐Rideal pathway and the vibration‐excited nitrogen molecule‐mediated Langmuir‐Hinshelwood pathway.

Study of Induction Heating of Metal Structures at Increased Frequency

Introduction. One of the conditions for trouble-free operation of moving and rubbing me­tal structures in winter is the absence of ice and snow accumulations in the operating areas of moving components. The same goes for moving agricultural constructions, which, for instance, can freeze to the surface outside the animal houses. In the article, based on the studying a turnout switch there is proposed the development of an innovative, more economical and cheaper method for heating moving parts. Aim of the Study. The study is aimed at creating a technology for heating sliding metal surfaces and at justifying parameters, developing and simplifying equipment design.Materials and Methods. Using a system approach, mathematical analysis and energy ba­lance methods, there were considered the main patterns of thermal processes in the contact zone of sliding metal structures. When considering these processes, there were made some assumptions. Namely, there were not taken into account soil thermal conductivity, air speed, and other physical processes, because they do not have a significant impact on the final results. These assumptions greatly simplify thermal calculations and obtaining the necessary analytical expressions to determine the parameters of induction heating elements.Results. The induction heating method for moving and rubbing metal structures in winter period has been proposed and tested, the main regularities have been revealed and technical characteristics have been determined. High efficiency and convenience of induction heating in comparison with other methods of electric heating have been proved. There have been obtained numerical values of parameters of induction heating elements, which agree with experimental data.Discussion and Conclusion. Based on the developed induction heating scheme, an experimental model with a power of up to 1 000 watts with a frequency of 10 kHz was made. The manufactured experimental model was studied in laboratory and production conditions. The estimated heating power of the part was 334 watts, the measured power was 351 watts. At the same time, the part weighing 20 kg heated up to 60 °C in 40 minutes. During production tests, the part was heated by 50 °C in 40 minutes.The research results can be used to design induction heaters operating at an increased frequency.

Laser Preparation and Underwater Drag-Reduction Performance of Secondary Fractal–V Groove Composite Structures on the Surface of Equal-Diameter Revolution Bodies

The reduction of drag for both aircraft and underwater equipment has the potential to reduce their overall energy consumption. Consequently, research into the drag-reducing performance of metal surfaces has significant practical applications. However, there has been more research on the machining of grooves on flat surfaces and inside tubes and less research on the structure of drag-reducing grooves on the outside of circular rods. This paper presents a study in which laser etching technology is employed to machine a range of secondary fractal topologies and V-groove composite structures on the surface of equal-diameter stainless-steel bodies of revolution. The influence of different parameters on the surface properties of stainless-steel materials is analysed through the use of auxiliary positioning tools, adjustments to laser processing parameters and scanning path schemes, as well as the characterisation of the surface morphology of the processed stainless steel using super-depth microscopy, scanning electron microscopy, and other techniques. Subsequently, an underwater drag-reduction tester is employed to assess the drag-reduction efficacy of the optimised secondary fractal composite structure on the surface of the stainless-steel equal-diameter body of revolution. Subsequently, particle image velocity (PIV) tracking technology is employed to assess the surface flow field velocity and overall velocity average of the secondary fractal composite structure. The findings indicate that the secondary fractal composite structure exhibited a drag-reduction effect on the surface of the stainless-steel body of revolution only when the primary main groove had a width of 0.1 mm. Furthermore, an increase in the Reynolds number Re within the range of 4000 to 7000 resulted in a notable enhancement in the drag-reduction efficacy of the secondary fractal composite structure on the surface of the stainless-steel body of revolution. At Re values of 5000, 6000, and 7000, the corresponding drag-reduction rates were observed to be 5.15%, 5.28%, and 5.40%, respectively.

Increasing the Resistance of Steel and Austenitic Stainless Steels Against Pitting Corrosion by a γ-Irradiated Self-Assembled Amphiphilic Molecular Layer

This study, based on our previous research, aims to quantitatively determine the enhanced protection of austenitic stainless steels against pitting corrosion in NaCl solution by self-assembled molecular (SAM) layers, in their original form and after γ-irradiation. This study focuses on four stainless steels of varying compositions, covered by self-assembled undecenyl phosphonic acid layers. The metal dissolution in corrosion experiments was measured by a special, highly sensitive analytical technique using the inductively coupled plasma–optical emission spectrometry (ICP-OES). The comparison of the dissolved metal ion concentrations measured in the presence of different metals with and without nanocoatings allowed the evaluation of the anticorrosion effectiveness of nanofilms as well as the importance of the alloying elements. The ICP-OES results demonstrated that the quality of layers have a significant impact on anticorrosion efficacy. The γ-irradiated self-assembled layers were the most effective in controlling the dissolution of stainless steels. The mechanisms of the inhibition in the presence of these nanolayers were elucidated by infrared spectroscopy. First of all, it revealed the differences in the adsorption of the undecenyl phosphonic acid self-assembled layer, both with and without γ-irradiation. The other important observation that confirmed the increased anticorrosion efficiency after γ-irradiation proved the formation of a more compact, polymer-like layer over the metal surface. The increased anticorrosion efficacy, defined as the enhancement in Pitting Resistance Equivalent Numbers (PRENs) in the presence of self-assembled layers (either pre- or post-γ-irradiation), can be documented.

Strong coupling between a quasi-two-dimensional perovskite and a honeycomb plasmonic nanocone array

Recently organic-inorganic perovskite has been established as a promising platform for achieving room temperature exciton-polaritons, attributable to its superior optical coherence and robust exciton binding energies. However, when interfaced with metallic surfaces, the rapid degradation and quenching effect in perovskite have presented significant challenges, which critically hinders the exploration of light-matter interactions within metallic plasmonic structures. In this study, we report a quasi-two-dimensional lead halide perovskite that demonstrates a pronounced strong coupling phenomenon within an array of aluminum nanocones. The investigated quasi-two-dimensional perovskite structure exhibits high photoluminescence quantum efficiency and improved stability against metallic-induced degradation. Interestingly, the periodical arraying in honeycomb formation of plasmonic structure has advantages in angle-dependent dispersions and the loss neutralizing effectively. Besides, the plasmonic cone lattice characterized by its collective surface lattice resonance, features an exceptionally small mode volume and high quality, enhancing its interaction with the perovskite. A significant Rabi splitting of 243 meV is observed at an incident angle of 30°. The dynamics of the Rabi oscillation is revealed by transient absorption spectra and theoretically analyzed by cavity quantum electrodynamics. This advancement in polariton research paves the way for novel applications, including quantum sources, enhanced photon-electron conversion efficiencies, and low-threshold lasing.

Effect of Temperatures on Green Synthesis of Amide-based Corrosion Inhibitors from Sustainable Source

This research addresses the critical need for effective anticorrosion solutions, focusing on the development of environmentally friendly coatings using Palm Fatty Acid Distillate (PFAD), a byproduct of crude palm oil production, as a key component in amide inhibitors. Traditional inorganic corrosion inhibitors pose environmental and economic concern due to their expense and toxicity while PFAD based amides promote a sustainable and cost-effective alternative. The synthesis of PFAD based amides using ethylenediamine in ethanol at reflux at various temperatures (25, 40, 60 and 90˚C) revealed that higher synthesis temperatures enhance inhibition properties. Amides containing double bonds and nitrogen-functional groups demonstrated excellent efficiency in attaching to metal surfaces. This study evaluates the synthesized amide’s inhibitory potential through physicochemical analysis using Fourier Transform Infrared Spectroscopy (FTIR) and corrosion inhibition efficiency using the Linear Polarization Resistance Method (LPRM). Physicochemical analysis using FTIR indicated the prominence of the amide group of N-H in the product with clear bonds at 1600 cm⁻¹, and visible amide groups of O-H at 3350 cm⁻¹. They showed the disappearance of the carboxylic acid (C=O) peak from the raw material of PFAD, indicating that the amide synthesis reaction occurred successfully. LPRM analysis revealed that the amides at 90°C achieved a 75% corrosion inhibition efficiency in a 3.5% NaCl solution, outperforming other tested temperatures. This efficiency is attributed to the adsorption of nitrogen-containing fatty amide molecules on the metal surface. These findings highlight the potential of PFAD based amides as green corrosion inhibitors, offering a promising solution for sustainable corrosion mitigation strategies.

High-resolution, high-speed, chromotropic color printing based on fs-laser-induced gold/graphene HSFLs

Through achieving high-spatial-frequency laser-induced periodic surface structures (HSFLs) on a gold/graphene hybrid film, we introduce a high-speed, high-resolution, and wide-gamut chromotropic color printing technique. This method effectively addresses the trade-off between throughput and resolution in laser coloring. To realize Au HSFL, disordered lattice structures and high transmittance of amorphous Au (a-Au) thin film are used to overcome the rapid hot-electron diffusion and loss of plasmonic coherence typically observed on low-loss metal surfaces, respectively. Coupled with crystallization in Au and modulated surface plasmon polaritons by artificial “seed” pre-structure growing in a SiO2/Si substrate, HSFL emerged with a period of 100 nm on crystalline Au after single and rapid femtosecond laser scanning. This equips the proposed color printing with high-resolution and high-speed features simultaneously. In addition, the crystallization process is demonstrated to initiate change in the complex refractive index of Au, which causes wide-gamut colors. The chromotropic capability, which facilitates the background color to be tailored in color as well as into desirable shapes independently, enables three-level anti-counterfeiting based on the proposed color printing. Therefore, the proposed color printing is amenable for practical implementation in diverse applications, including security marking and data storage, ranging from nanoscale to large-scale fabrication.

Exploring the Broad Spectrum of Titanium-Niobium Implants and Hydroxyapatite Coatings-A Review.

Tooth loss replacement using dental implants is becoming more frequent. Traditional dental implant materials such as commercially pure titanium and titanium aluminum vanadium alloys have well-proven mechanical and biological properties. New titanium alloying metals such as niobium provide improved mechanical properties such as lower elastic modulus while displaying comparable or even better biocompatibility. Hydroxyapatite coatings are a well-documented and widely used method for enhancing dental implants' surface characteristics and properties and could provide a useful tool for further enhancing titanium-niobium implant properties like osteointegration. Among several coating techniques, physical deposition methods and, in particular, vapour deposition ones are the most used due to their advantages compared to wet deposition techniques for hydroxyapatite coating of metallic surfaces like that of dental implants. Considering the scarcity of data concerning the in vivo evaluation of titanium-niobium biocompatibility and osteointegration and the lack of studies investigating coating these new proposed alloys with hydroxyapatite, this review aims to further knowledge on hydroxyapatite-coated titanium niobium alloys.

Effect of 2-Mercapto-1-methylimidazole on the Dual Action of Chemical Mechanical Polishing of Cu and Ta.

When chemical mechanical polishing (CMP) of tantalum (Ta)-based barrier layers is done through silicon via (TSV), it is necessary to control the rate selection of copper (Cu) and Ta to prevent the formation of dishing pit formation due to the rapid removal rate (RR) of copper in the via compared to tantalum outside the via. This paper selected 2-mercapto-1-methylimidazole (TAMZ) as an inhibitor, which has the dual effect of reducing the RR of Cu and increasing the RR of Ta. The experimental results show that the rate selection ratio of Cu and Ta is up to 2.12:1, the inhibition rate of TAMZ on Cu is up to 98.37%, and it can control Cu-Ta galvanic corrosion; the mechanism of TAMZ on Cu and Ta was studied by XPS, SEM, AFM, and other experiments. Theoretical calculation found that TAMZ formed chemical bonds with the metal surface mainly through N and S atoms and could be adsorbed on the surface of Cu and Ta by mixed adsorption, which clarified the inhibition mechanism of TAMZ from a microscopic perspective.

Electrochemically Stable and Ultrathin Polymer-Based Solid Electrolytes for Dendrite-Free All-Solid-State Lithium-Metal Batteries

Abstract Polymer-based composite solid electrolytes (PCSEs) are increasingly studied in all-solid-state lithium-metal batteries (ASSLMBs) due to the combined advantages of better flexibility of polymer and higher ion conductivity of ceramic electrolytes. However, most reported PCSEs are overly thick, increasing internal resistances. Besides, the poor stability at the Li metal-electrolyte interfaces often leads to severe lithium dendrite formation and reduced cycling stability. Here, we fabricate an ultrathin PCSE with a thickness of 12.4 μm, incorporating polyacrylonitrile (PAN) nanofibers as the structural matrix, and a filler with polyethylene oxide and Li6.5La3Zr1.5Ta0.5O12 (LLZTO). Due to the formation of the LiCN layer on the surface of the lithium metal and the Li-ion transport pathways induced by the dehydrocyanation reaction at the LLZTO/PAN interfaces, the PCSE exhibits a high critical current density of 1.8 mA cm-2 and a low energy barrier of 0.278 eV for Li-ion transfer, accommodating the fast Li-ion migration to avoid Li-dendrite growth. In addition, the stable nitrile groups and the dehydrocyanation reaction ensure the electrochemical stability of the PCSE with a high oxidation voltage of 5.5 V and an exceptional cycling stability (2100 h) in Li||PCSE||Li symmetric cells. Additionally, the Li||PCSE||LiFePO4 full cells demonstrate a high volumetric energy density of 338.3 Wh L-1 at 0.1 C and a robust stability over 100 cycles at 0.5 C. The study offers a new approach for fabricating ultrathin PCSEs and provides insights into the mechanisms of dendrite-free formation, guiding the development of high-performance PCSEs for ASSLMBs.

Improved Method for Methane Pyrolysis Rate Measurement using Molten Metal Catalysts for Turquoise Hydrogen Production

Abstract To develop low-$$\hbox {CO}_2$$ CO 2 emission ferrous metallurgical process, $$\hbox {H}_2$$ H 2 -based ironmaking processes are being actively developed. Several technologies are being developed to provide a sufficient mass of $$\hbox {H}_2$$ H 2 in an environmentally friendly manner. One of such processes is “turquoise” $$\hbox {H}_2$$ H 2 , based on a natural gas pyrolysis such as $$\hbox {CH}_4$$ CH 4 (g) $$\rightarrow $$ → 2$$\hbox {H}_2$$ H 2 (g) + C(s), thereby minimizing $$\hbox {CO}_2$$ CO 2 emission. The reaction could be catalyzed using molten metals in a bubble column reactor. Therefore, the selection of the molten metal catalyst is important for enhancing the reaction efficiency and for minimizing the production cost. In the previous research of the present authors, a new methodology for the pyrolysis rate measurement was introduced by employing an electromagnetic levitation heating of catalytic molten metals followed by quadrupole mass spectrometer (QMS) analysis to assist in the selection of the catalyst metal. However, a potential source of error in this technique was identified. Therefore, two modifications of the methodology are reported in the present study: (1) changing the heating and feed gas supply patterns and (2) gas analysis technique from QMS to Gas Chromatography (GC). Accordingly, the reported pyrolysis rate of pure In, Ga, Bi, Sn, and Cu of the previous study was revised in the present study. It was revealed that Ga and In emitted non-negligible amounts of $$\hbox {H}_2$$ H 2 upon heating, even without the fuel gas ($$\hbox {CH}_4$$ CH 4 ). This was regarded as a noise in the $$\hbox {H}_2$$ H 2 signal measured by GC. On the other hand, Cu, Sn, and Bi did not show the noticeable $$\hbox {H}_2$$ H 2 (noise). The modified method provides $$\hbox {H}_2$$ H 2 production rate by the pyrolysis, by separating the noise in the regime of the chemical reaction control at the surface of the molten metals. $$1^\text {st}$$ 1 st -order reaction was confirmed. Graphical Abstract

Advances in Phosphorus-Based Catalysts for Urea Electrooxidation: A Pathway to Sustainable Waste to Energy Conversion Through Electrocatalysis

The electrocatalytic oxidation of urea has gained significant attention as a promising pathway for sustainable energy conversion and wastewater treatment that could address the dual goals of waste remediation and renewable energy generation. Phosphorous function groups-based catalysts have been introduced as potential electrode materials for enhancing the urea electrocatalytic oxidation reaction (UEOR) due to their unique structural properties, high stability, and tunable electronic characteristics. This review presents recent advancements in phosphorous-based catalysts (phosphates/phosphides) for UEOR. It highlights the development of novel phosphorous materials, synthesis approaches, and electrocatalytic insights into urea electrooxidation on phosphorous-based materials surfaces. Key topics include the role of different metal phosphates, surface modifications, and compositional optimizations to improve electrocatalytic efficiency and durability. Through a critical evaluation of current research trends and technological progress, this review underscores the potential of phosphate-based catalysts as environmentally friendly and efficient alternatives for sustainable waste-to-energy conversion via UEOR. The review concludes with a perspective on future directions for optimizing phosphate catalysts, scaling up practical applications, and integrating UEOR systems into renewable energy infrastructures.

Novel variant transformer-based method for aluminum profile surface defect detection

Abstract The detection of surface defects on metal plays a pivotal role in the evaluation of product quality for aluminum profiles. So far, the most prevalent approach for detecting metal surface defects is still through the utilization of traditional conventional neural networks (CNNs). However, transformer-based methods have made notable improvements in computer vision in recent years, exhibiting superiority over traditional CNNs in the majority of tasks. In regard to aluminum surface defect image characteristics, such as intricate textures, few defect samples, and large-scale differences in various defects, traditional CNNs have difficulty further improving performance. This paper proposes a novel method based on a variant transformer for surface defect detection of aluminum profiles, which combines a traditional CNN and a transformer architecture with a deformable attention module (DAM). The DAM better focuses on part of critical sampling points around the reference point, which alleviates the unacceptable complexity in high-resolution feature maps and enhances the recognition effect of small target defects. The image stitching method proposed uses defect-free samples to generate new samples, which partially mitigates the issue of class imbalance. Moreover, we carried out supplementary experiments to confirm the effectiveness of transfer learning in training small-scale datasets. Compared with the baseline, the mean average precision (mAP) was improved by 3.32%. Extensive experimental results demonstrate the efficacy of our method in accurately detecting surface defects of aluminum profiles and significantly improving the detection of small target defects.