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Water purity plays a key role in medical applications such as clinical diagnosis, drug delivery, sterilization, and patient management. One of the most important medical treatments in which the quality of water is very important is hydrotherapy. Most of the patients have weakened immune systems due to existing infections, making them highly vulnerable to new infections from contaminated water in hydrotherapy pools. Therefore, the hydrotherapy water should be tested to ensure the safety of the patients' lives. In this research, a fiber optic bilayer sensor consisting of silver, copper, platinum, nickel, and gold as the metal layer, and scandium oxide as the second layer, has been numerically simulated to test water purity for hydrotherapy applications. The proposed configuration gives water purity detection with a maximum sensitivity of 4594.0°/RIU for Ni/Sc2O3 while the contacting length is considered as 10 mm, which is much higher than the conventional sensor. It is a topic of interest to researchers in related areas. Ag/Sc2O3 exhibits the highest figure of merit value compared to other materials. At the second part of the study, the effect of a silver-aluminum alloy has been investigated to enhance the quality factor of the winner structure (Ag/Sc2O3). The most efficient silver-aluminum combination ratio is found to be 0.1:0.9, which enhances the sensor quality factor from 40.50 to 60.45 (RIU−1) in aqueous media, while the refractive index of water changes from 1.33 to 1.34. [ABSTRACT FROM AUTHOR]

The study focused on the synergistic effect of cellulose nanofibrils (CNFs) as a lignocellulosic bionanomaterial and nickel-titanium (NiTi) alloy as a shape memory smart metallic material reinforcer on the thermal properties of sustainable smart composites. The casting process was used to produce composites with CNF loadings of 1%, 3%, and 5% and NiTi loadings of 3% into epoxy resin. Thermal properties were evaluated using thermogravimetric (TGA), derivative thermogravimetric (DTG), differential scanning calorimetry (DSC), and dynamic mechanical thermal (DMTA) analysis. The TGA results revealed that the CNF/NiTi-reinforced groups have considerable higher degradation temperatures and thermal stability than the control group. Also, at 800°C, CNF/NiTi-reinforced groups had a higher residual content than the control group. DTG results showed that the addition of CNFs decreased the degradation speed. Although the NiTi loading was constant, it was determined that the addition of CNFs increases the storage modulus (E′), loss modulus (E″), tan delta (Tan δ), and glass transition temperature (Tg). Overall, it can be concluded that CNF/NiTi-reinforced composites indicated significantly improved thermal stability, decomposition temperature, residual content, elastic, and viscous properties. These smart composites can be used for advanced material applications requiring thermal stability. [ABSTRACT FROM AUTHOR]

The development of effective and stable electrocatalysts for the hydrogen evolution reaction (HER) in acidic electrolytes is a significant challenge. In this work, homogeneous Pt nanodendrites (Pt NDs) with a PtIr shell were successfully synthesized by a two-step wet chemical method. This open three-dimensional (3D) dendritic structure exhibited exceptional electrocatalytic characteristics, exposing as many active sites as feasible. Furthermore, by alloying Ir with Pt on the surface, catalytic activity was greatly enhanced while ensuring extremely high stability. Iridium surface-enriched platinum nanodendritic catalysts (Pt@PtIr NDs) outperformed the control samples and the commercial catalysts. In acidic HER test, Pt@PtIr NDs had a lower overpotential (22 mV) than Pt NDs (26 mV) and commercial Pt/C (31 mV) at 10 mA/cm2, and the activity of Pt@PtIr NDs remained consistent even after undergoing a continuous durability test for at least 168 h, which was much superior to the performance of commercial Pt/C (10 h) under identical test conditions. This study revealed that the application of 3D Pt dendritic metal alloys may offer a chance for the development of enhanced electrocatalysts in acidic HER. [ABSTRACT FROM AUTHOR]

Alloying nanoclusters (NCs) has emerged as a widely explored and versatile strategy for tailoring tunable properties, facilitating in‐depth atomic‐level investigations of structure‐property correlations. In this study, we have successfully synthesized six atomically precise copper NCs alloyed with Group 10 metals (Pd or Pt). Notably, the Pd0 or Pt0 atom situated at the center of the distorted hexagonal antiprism Pd0/Pt0@Cu12 cage, coordinated with twelve Cu+ and two tBuC≡C− ligands. Moreover, ligand exchange strategies demonstrated the potential for Cl− and Br− to replace one or two alkynyl ligands positioned at the top or side of the NCs. The chirality exhibited by these racemic NCs is primarily attributed to the involvement of halogens and a chiral (Pd/Pt)@Cu18 skeleton. Furthermore, all the NCs exhibit near‐infrared (NIR) luminescence, characterized by emission peaks at 705–755 nm, lifetimes ranging from 6.630 to 9.662 μs, and absolute photoluminescence quantum yields (PLQYs) of 1.75 %–2.52 % in their crystalline state. The experimental optical properties of these NCs are found to be in excellent agreement with the results of theoretical calculations. These alloy NCs not only offer valuable insights into the synthesis of Pd0/Pt0‐Cu alloy NCs, but also bridge the gap in understanding the structure‐luminescence relationships of Pd0/Pt0‐Cu molecules. [ABSTRACT FROM AUTHOR]

Atomic layer deposition was applied on mesoporous silica to synthesize a highly dispersed gallium oxide catalyst. This system was used as starting material to investigate different loadings of nickel in the dehydrogenation of propane under industrially relevant, Oleflex‐like conditions. The formation of NiGa alloys was confirmed by X‐ray diffraction analysis and electron microscopy. Surprisingly, the nanoalloys enhanced the selectivity towards C3H6 while decreasing the tendency for coking. Herein, in situ thermogravimetry, and measured mass fractions of carbon revealed that the coking rate was reduced by over 50 % compared to the pristine gallium oxide. Generally, the increased selectivity can be explained by the partial hydrogenation and reduction of the gallium oxide surface. The optimum temperature for the removal of deposited carbon was evaluated by a temperature programmed oxidation. Finally, the best‐performing Ni−GaOx catalyst was employed in a cycled experiment with periodic reaction and regeneration tests. After regeneration, the selected Ni−GaOx catalyst provided a higher yield of propylene compared to the unmodified gallium oxide. [ABSTRACT FROM AUTHOR]

BACKGROUND: Micro-arc oxidation can effectively add bioactive elements to the metal surface and improve the anti-bacterial and anti-inflammatory properties of biomedical metal materials, so this technology has become one of the hotspots of biomedical materials. OBJECTIVE: To summarize the anti-bacterial and anti-inflammatory properties of surface coatings prepared by the combination of micro-arc oxidation and other surface modification technologies. METHODS: Articles from January 1996 to December 2022 were searched on CNKI, WanFang and PubMed databases using Chinese and English search terms “micro-arc oxidation, antibacterial properties, anti-inflammatory properties, metal implants”. After preliminary screening according to inclusion and exclusion criteria, 89 articles were retained and summarized. RESULTS AND CONCLUSION: The ceramic layer prepared by micro-arc oxidation can improve the anti-bacterial and anti-inflammatory properties of titanium, magnesium and other alloys. Combination with other surface modification technologies can effectively solve the effect of pores on the surface properties of the alloy, and further improve the biological properties of the oxide film. It has a wide application prospect in orthopedics and dentistry. At present, most studies are limited to metal coatings, and most of them focus on metal elements with good antibacterial properties such as silver and copper, while only a few studies mention non-metallic coatings such as graphene oxide, hydroxyapatite and chitosan. In the future, extensive studies can be conducted on inorganic coatings and polymer coatings, and more combinations of different bioactive elements can also be adopted to improve antibacterial properties. Currently, studies on the inflammation of implant coatings prepared by micro-arc oxidation are mostly limited to the immune system and focused on macrophages, while studies on neutrophils and platelets are scarce. In the future, a variety of advanced technologies should be combined to explore the specific effects of micro-arc oxidation coating on other immune cells and inflammatory cells. [ABSTRACT FROM AUTHOR]

Detection of water impurities is an important issue in many applications, especially in the medical field. In this paper, a fiber optic sensor based on surface plasmon resonance has been numerically simulated and is used for detecting 10% glucose (called dextrose 10%). This sensor consists of two layers, the first layer is metal such as cobalt, nickel, platinum, and silver and the second layer is barium titanate. The sensor performance parameters were calculated using the normalized transmitted power in three different values of 300, 600, and 900 microns of fiber core diameter. Ag/BaTiO3 with 900 microns fiber core is the most qualified structure. In the second part of the research, the effect of aluminum–silver alloy has been investigated to enhance the quality factor of Ag/BaTiO3. The combination ratio of Ag–Al (0.1:0.9) was the best choice to increase the quality factor of the sensor from 62.46 (RIU-1) to 88.0 (RIU-1). [ABSTRACT FROM AUTHOR]

PdZn/TiO2 catalysts have been investigated for the hydrogenation of CO2 to methanol. Varying the ratio of Pd and Zn using TiO2 as a support has a dramatic effect on catalytic performance. Chemical vapour impregnation was used to produce PdZn alloys on TiO2 and X-ray diffraction, X-ray photoelectron spectroscopy, and scanning transmission electron microscopy revealed changes in the structure at varying total PdZn molar ratios. Compared to monometallic Pd/TiO2, introducing a low loading of Zn drastically changes product selectivity. When Pd is alloyed with Zn above a total Zn/Pd = 1 molar ratio, methanol selectivity is improved. Therefore, for enhanced methanol productivity, it is crucial for the Zn loading to be higher than that required for the stoichiometric formation of the 1:1 β-PdZn alloy. [ABSTRACT FROM AUTHOR]

As the widely used ultraviolet (UV) filter, Ensulizole (ELZ), has been proven as an environmental hormone, development of useful techniques for eliminating ELZ is imperative. Since SO4·−-based oxidation technologies are promising for treating emerging contaminants, and cobalt (Co) appears to be an extremely useful catalyst for monopersulfate (MPS) activation, that would be critical to construct advantageous cobaltic catalyst of MPS activation. A unique activator would be derived from a special metal organic framework ([Co]pyrazine[Ni(CN)4]) which is carbonized to become a nanocluster comprised of CoNi alloy nanoparticles (NPs) confined in carbon nanospheres, and nanotubes, forming CoNi@Carbon (CNC). Such a CNC nanocomposite would exhibit several promising properties: (1) as Co is the extremely effective metal for MPS activation, CoNi is expected for offering superior performance for activating MPS; (2) high magnetization of CoNi alloy would equip CNC with a magnetically-controllability; (3) CoNi encapsulated in carbon is guarded to enhance its reusability; (4) the interlaced configurations of CNC also make it to show higher active sites for MPS activation. Thus, CNC exhibits a significantly stronger activating capability than Co3O4, which is the conventional heterogeneous catalyst for MPS. CNC/MPS also displays a lower activation energy (Ea) for ELZ degradation than literatures, showing advantages of CNC. Mechanisms for MPS activation and ELZ degradation were also elucidated to further understand elimination process of ELZ by MOF-derived cobaltic catalysts. [ABSTRACT FROM AUTHOR]

For the first time, the mechanism of metal aluminum dissolution in NaF–ScF3 eutectic melts and the chemical interaction between the constituents of this mixture have been thoroughly studied by a combination of differential thermal analysis (DTA), high temperature and solid-state nuclear magnetic resonance (NMR), and X-ray diffraction (XRD) coupled with the molecular dynamic simulations. The formation of an insoluble Al3Sc alloy in molten (NaF–ScF3)eut system was proven, and the chemical mechanism of this aluminothermic Al3Sc alloy production was elucidated. Corresponding ex situ examinations bring to light the formation of NaScF4 and solid solution of Na3(Al,Sc)F6 in cooled bath. The molecular dynamics calculations of the bath allow us to construct the structural model and to predict viscosity, density and electrical conductivity of the reagent melt to help to optimize the conditions of the alloy synthesis. [ABSTRACT FROM AUTHOR]

Doped and alloyed transition metal-oxides (TMOs) attract vast attention owing to their tunable electronic properties (e.g., conductivity, band gap, and optical absorption), making them appealing for many (photo)-electronic, chromic, and green energy applications. Dual-functional materials combining electrochromic (EC) and energy storage (e.g., supercapacitor, SC) applications are of interest as they can store energy while shading the light transmission through a window or give off a visual signal of their current energy storage state by a color change. Pure tungsten-oxides exhibit distinctive EC properties but attain low energy density compared to other TMOs (e.g., MoO3 and V2O5). The coloration efficiency and energy density can be enhanced by controlling the morphology, size, and composition of the nanoscale TMOs that constitute the active EC film. Thus far, most EC-SC works showed a trade-off between increased areal capacitance and a decrease in the coloration efficiency or transmittance; the improved EC-SC properties for doped or alloyed metal-oxides were related mostly to the small grain size or to structural distortion caused by the added cation, exhibiting more active sites. Herein, we demonstrate a straightforward and facile synthesis of crystalline Mo/V-alloyed tungsten-oxide ultrathin nanowires (uNWs). We investigated the growth mechanism and succeeded in preserving the crystallinity up to 25% (atomic) alloying. The additional properties (compared to unmodified tungsten-oxide) of the alloyed uNWs, such as absorbance peaks, lead to improved specific capacitance while preserving the high coloration efficiency of uNW W–O, and in the case of W–Mo–O, a better coloration efficiency is measured. [ABSTRACT FROM AUTHOR]

The MCrAlY bonding layer alloy was prepared by vacuum melting, and the alloy composition was NiCoCrAlY and NiCoCrAlYHfTa. The high-temperature cyclic oxidation experiment was carried out in air at 1050∘C until it failed. The results show that Hf and Ta have a significant influence on the oxidation resistance of the alloy. The doped specimens have longer oxidation lifetimes compared to the undoped samples. The study also found that the Hf would diffuse out and combine with O to form HfO2 in the thermally grown oxide (TGO) layer, which would improve the adhesion and reduce the wrinkles of the oxide layer. Ta in the doped specimens hinders the diffusion of Al and reduces the oxidation rate, while improving the thermal mismatch. Therefore, the specimens doped with both Hf and Ta have the highest oxidation lifetimes, though the oxidation lifetime was 10 times longer than that of the undoped specimens. It is indicated that the doping of Hf and Ta is an important method to improve the oxidation lifetime of thermal barrier coatings (TBCs). [ABSTRACT FROM AUTHOR]

This article reviews the use of various types of platinum (Pt)-free materials as cathode for dye-sensitized solar cell. The materials such as conducting polymers, alloys, metal sulphide, metal nitride and metal selenide have been applied as a cathode in the device using TiO2 photoanode, Ru-based dye and a liquid electrolyte containing I–/I3– for Pt substitution. The use of binary, ternary and quaternary metal chalcogenides has been highlighted in this review. The efficiency of the device with those materials has been compared with that of Pt-based device counterparts. The electrochemical impedance spectroscopy, cyclic voltammetry, Tafel parameters and also incident-photon conversion efficiency correlating with power conversion efficiency have been discussed. [ABSTRACT FROM AUTHOR]

The development of inexpensive and robust bifunctional electrocatalysts for hydrogen evolution reactions (HER) and oxygen evolution reactions (OER) was crucial for renewable energy systems. Herein, a novel strategy for preparing CoNiRu alloy nano‐electrocatalyst capsulated by nitrogen‐doped biochar (CoNiRu@NLC) using carboxymethylated lignin macromolecules was proposed. CoNiRu@NLC exhibited excellent HER and OER performance, and the overall water splitting voltage was only 1.47 V at 10 mA/cm2 with excellent catalytic stability, which was superior to the noble metal catalysts Pt/C ‖ RuO2. Theoretical calculations confirmed the strong electron interaction between CoNiRu alloy and carbon layer, and XPS patterns proved that the electrons transfer from Ru to CoNi, significantly boosted the electrocatalytic activity. This study demonstrated the importance of lignin‐driven alloying on enhancing catalytic performance and provided a concept for the development of high‐efficiency catalysts and high‐value utilization of polyphenol biomass. [ABSTRACT FROM AUTHOR]

The Nickel tungsten (Ni-W) alloy was electrodeposited on stainless steel (SS) substrate using potentiostatic mode at room temperature. Potentiostatic electrodeposition was carried out by varying the deposition time. The physicochemical properties of Ni-W alloys were studied using X-Ray diffraction (XRD), Electron Microscopy and micro-Raman spectroscopy. Recorded XRD spectra was compared with standard JCPDS card and the presence of Ni was confirmed, no such peaks for W were observed. Further study was extended for micro-Raman analysis. From Raman spectroscopy study the appearance of Ni-O and W6+=O bonds confirms that the Ni-W present in amorphous phase. Several cracks were observed in SEM images along with nanoparticles distributed over the electrode surface. The appearance of cracks may be correlated with the in-plane tensile stresses, lattice strains and stacking faults and maybe related to the substrate confinements. [ABSTRACT FROM AUTHOR]

High-strength, high-conductivity copper/silver-alloyed materials were prepared by cold-spray (CS) manufacturing. For DC high-field application at room temperature, bulk Cu/Ag (5% vol. Ag) alloys with high mechanical properties and high electrical conductivity can be obtained by CS and post-heat treatments. For pulsed-field application at liquid nitrogen temperature, bulk Cu/Ag (5% vol. Ag) alloys serve as precursors for room-temperature wire drawing. The Cu/Ag-alloyed bulk CS deposit presents a high yield strength of about 510 MPa with a corresponding electrical resistivity of 1.92 µΩ·cm (at 293 K). The Cu/Ag-alloyed wires show a very high ultimate tensile strength (1660 MPa at 77 K or 1370 MPa at 293 K) and low electrical resistivity (1.05 µΩ·cm at 77 K or 2.56 µΩ·cm at 293 K). Microstructural studies via STEM allow us to understand this very high level of mechanical strength. The results evidence that materials developed by CS exhibit very high mechanical properties compared to materials prepared by other routes, due to the high velocity of the deposited particles, which leads to high initial deformation rates and specific microstructural features. [ABSTRACT FROM AUTHOR]

This manuscript proposes a hybrid method to predict the optimal nano‐metal matrix composites. The proposed hybrid technique is the wrapper of the Fire‐Hawk Optimizer (FHO) and Spiking Neural Network (SNN). Commonly it is known as FHO‐SNN method. The main objective of the proposed method is to improve the method parameters for better enhancement in mechanical properties. FHO approach is used to improve the process parameters of stirring squeeze casting method. The SNN predicts optimal parameters. Moreover, the problem based on the casting is reduced. By then the proposed hybrid technique performance is performed in the MATLAB platform and associated with various existing approaches. The proposed system shows the high tensile strength, impact energy and hardness compared with other existing methods. [ABSTRACT FROM AUTHOR]

Experiential education is widely recognized as an effective teaching method for nurturing students’ problem-solving abilities and fostering innovative thinking through hands-on activities. Furthermore, the field of 3D printing of alloy materials has garnered significant attention in the realm of electrocatalysis. This paper aims to synergize experimental education with 3D printing of alloys, exploring its impact on students and educational outcomes. Initially, the paper introduces the importance and role of experimental education and the characteristics and potential applications of alloy materials. Subsequently, the potential utilization of 3D printing technology in the fabrication of alloys is discussed. To enhance students’ engagement, learning motivation, and scientific literacy, they actively participate in designing and conducting experiments. The primary objective of this research is to provide novel ideas and methodologies for educational practices, cultivating students’ scientific thinking and practical abilities. Additionally, it aims to foster a greater number of innovative talents in the field of materials science and engineering. [ABSTRACT FROM AUTHOR]

Advancements in computer capabilities enable predicting process outcomes that earlier could only be assessed after post-process analyses. In aerospace and automotive industries it is important to predict parts properties before their formation from liquid alloys. In this work, the logistic function was used to predict the evaporation rates of the most detrimental impurities, if the temperature of the liquid aluminum alloy was known. Then, parameters of the logistic function were used to determine the transition points where the reaction order was changing. Samples were heated to 610 °C, 660 °C, 710 °C, and 760 °C for one hour, after which the chemical analyses were performed and evaporation rates were calculated for Cd, Hg, Pb and Zn elements. The pressure inside the encapsulated area was maintained at 0.97 kPa. Whereas parameters that define the evaporation rate increase with the temperature increase, the maximum evaporation rates were deduced from the experimental data and fitted into the logistic function. The elemental evaporation in liquid-aluminum alloys is the best defined by the logistic function, since transitions from the first to zero-order-governed evaporation reactions have nonsymmetrical evaporation rate slopes between the lowest and the highest evaporation rate point. [ABSTRACT FROM AUTHOR]

The corrosion behavior of 316 stainless steel (316 SS) in NaCl–KCl–FeCl3 molten salt and vapor was studied at 300°C for 150, 300, and 500 h in Ar. The weight change, the micromorphology, element distribution, and crystal structure of the 316 SS alloy were analyzed by scanning electron microscopy, energy‐dispersive spectroscopy, and X‐ray diffraction. 316 SS alloys suffered from weight loss, significant visible corrosion shedding, and corrosion holes. The corrosion holes and corrosion shedding block of the 316 SS alloys become more and more serious with the increase in corrosion time. The corrosion depth of the corroded 316 SS alloys in NaCl–KCl–FeCl3 molten salt and vapor for 500 h can even reach up to 20.0 and 14.0 μm, respectively. 316 SS alloys in NaCl–KCl–FeCl3 molten salts underwent a more serious corrosion attack than that in the NaCl–KCl–FeCl3 vapor at 300°C due to the strong oxidizing compound FeCl3 in the molten salt. It not only offers a new insight into the corrosion behavior of 316 SS alloys in the chloride salts and corresponding vapor but also enriches the corrosion databases of the chloride salts. [ABSTRACT FROM AUTHOR]

Laser induced breakdown spectroscopy (LIBS) technology is minimally affected by strong magnetic fields that exist in tokamak nuclear fusion devices, and thus LIBS is regarded as a promising technique for in-situ diagnosis of plasma facing materials (PFMs) in tokamaks. Currently, LIBS has been employed for diagnosing PFMs in several tokamaks. However, LIBS still faces significant challenges, including the limitation of detection (LOD) for surface elements of PFMs, quantitative analysis, and determination of the serviceability status of PFMs in tokamaks. In this study, a co-axial femtosecond-nanosecond dual-pulse laser-induced breakdown spectroscopy(fs-ns-DP-LIBS) technique was developed. In the fs-ns-DP-LIBS technique, a femtosecond laser with high peak power and low laser energy was employed to induce a plasma, and then a nanosecond laser was used to enhance the emission intensity of LIBS signal. This enhancement was aimed to improve the LOD of conventional single-pulse LIBS. Moreover, six standard samples were used to quantify the major elements using the fs-ns-DP-LIBS technique, and several machine learning methods were further employed to classify the six standard samples. The results showed that under single nanosecond and single femtosecond LIBS measurements, except for the Cr emission lines, the Ni, Fe, and Mo emission lines were not observed in the wavelength range of 400-800 nm. However, it was worth noting that Ni I 498.02 nm, Fe I 517. 16 nm, Fe I 523.85 nm, Mo I 588.83 nm, and Mo I 603.07 nm emission lines were clearly observed when a 2 µs delay time between the femtosecond and nanosecond laser was used for Fs-ns-DP-LIBS. Additionally, the emission intensity of the Cr emission line was significantly enhanced. Compared with the nanosecond single-pulse LIBS measurements, the emission intensity of the Cr I 534.58 nm line increased by approximately seven times. The quantitative analysis results showed that the calibration curves generated by the fs-ns-DP-LIBS technique had higher fitting degrees(R²), and the LOD for Cr was improved by approximately 3.5 times. Furthermore, classification studies were conducted using decision trees, nearest neighbors, linear discriminant analysis, and support vector machines to classify the six samples. It showed that the classification prediction accuracy of linear discriminant analysis and support vector machines exceeded 99%. These findings highlight the potential of the presented method for diagnosing surface elements of PFMs, quantitative analysis, and determination of the serviceability status of PFMs. [ABSTRACT FROM AUTHOR]

TiAl alloys with different Al atomic compositions, i.e. Ti45Al, Ti48Al, and Ti51Al, were produced via double-wire arc-based additive manufacturing by altering the aluminum wire feed rate. The microstructure and mechanical performance of deposited parts were researched. By changing the aluminum composition from 45 at% to 51 at%, the microstructure in the uniform area transforms from equiaxed α2/γ lamellar and near-lamellar colonies to dual-phase structures and near-lamellar colonies, the volume fraction of α2 phase decreases from 46.5% to 12.4%, and the total microhardness decreases from 411 to 356 HV. As the aluminum composition increases, the compressive strength presents an increasing trend first and then a decreasing trend, and the compressive ratio presents an increasing trend. The maximum compressive strength and compressive ratio in the vertical and horizontal orientations are 1822.5 MPa, 1732.5 MPa, 19.9%, and 20.2%, respectively. [ABSTRACT FROM AUTHOR]

The diamond grits pre-brazed using an amorphous nickel (Ni)-based alloy were accurately fixed onto some positions on a steel substrate by resistance spot welding with a hot-pressing function. The amorphous Ni-based alloy thoroughly wetted and wrapped the diamond grits in the pre-brazing process. After the resistance spot welding, the pre-brazed diamond grits and steel substrate formed a strong metallurgical bonding under resistance heat and electrode pressure. The diamond grits welded by resistance spot welding maintained sharpness similar to that of regular diamond grits. The maximum tensile stress of welded diamond grits pre-brazed using amorphous alloy reached up to 0.43 GPa. The stress state was attributed to the presence of carbides of moderate magnitude between the bonded cladding and diamond grits. Grinding tests showed that the grinding performance of welded diamond grits pre-brazed using amorphous Ni-based alloy was better than that of welded diamond grits pre-brazed using crystalline Ni-based alloy. [ABSTRACT FROM AUTHOR]

Graphene electrodes were firstly printed on recycled single‐use‐packets. Later, the Ni50Mn35In15 (NMI) alloy or Ca2.9Nd0.1Co3.9Cu0.1O9, (CNCCO) misfit perovskite was deposited on the graphene electrodes to enhance their capacitive performance. Next, flexible supercapacitors (SCs) were assembled by using such electrodes. The SCs made with NMI and CNCCO powders were named as GNMI‐SC, and GCNCCO‐SC, respectively. Those ones produced capacitances/energy‐densities of 761.8 F g−1/152.6 Wh kg−1 and 207.7 F g−1/41.6 Wh kg−1, respectively. Subsequently, a mixture 1 : 1 of NMI and CNCCO powders was melted/coalesced at 1700 °C by using a plasma treatment in argon atmosphere and obtained in this way a NMI/CNCCO composite powder. The SC made with this last composite generated a capacitance/energy‐density of 1235.2 F g−1/247.3 Wh kg−1. Those last values are 62–500 % higher than these for the GNMI‐SC, and GCNCCO‐SC devices. Other benefits obtained after the introduction of the NMI/CNCCO powders into the SCs were: 1) the formation of additional Cu2+, Mn4+, Nd2+ and In3+ species, which enhanced the capacitance; 2) the capacitance retention was maintained above 93 % after 500 cycles of charge discharge; and 3) the lowest values of series and charge transfer resistances were obtained, which favored the ion diffusion/storage in the SC electrodes. [ABSTRACT FROM AUTHOR]

Previous studies have shown that various additives can greatly improve the properties of copper based electrodes. In this paper, the influence of Cr content changes and different pressing and sintering process parameters on mechanical and physical properties was investigated. The results showed that 2 vol.% Cu-Cr powder composite alloys prepared by pressing pressure 450 MPa and sintering temperature of 1100 °C had the optimal mechanical and physical properties, and its density, porosity, hardness and tensile strength were 8,35 g/cm³, 2%, 124 HB and 264 MPa, respectively. In addition, the hardness was increased by 5-7% compared with that of pure copper prepared by conventional casting method. [ABSTRACT FROM AUTHOR]

Consumption of rare-earth metal (REM) oxides, such as cerium and lanthanum, is significantly lower than their production. This discrepancy is attributed to the complex extraction of all REMs, where the share of cerium is approximately 40%. This article proposes a method for processing REM oxides for their use as master alloys in ferrous metallurgy products. REMs, in the form of modifiers for steels and alloys, are widely used. However, despite their wide usage, owing to the complexity of the REM production technology, they tend to have a high market value. This study explores the preparation of a cerium carbide (CeC2) master alloy for the modification of steels and cast irons. The proposed method aims to reduce the cost of the alloying process and simultaneously increase the demand for REM oxides. Using a high-temperature synthesis process, CeC2 was obtained for the modification of steel and cast iron. For this purpose, cerium dioxide (CeO2), graphite (C), and ARMCO-iron (Fe) were mixed in a specific percentage ratio by weight: 5.4% C, 19.5% CeO2, and 75.1% Fe. Following this, the reaction mixture was heated in a furnace to a temperature of 1650°C and held for 30 min, with a residual pressure in the furnace of 10–1 mbar. The synthesis was performed in the temperature range of 1300–1650°C, with the highest reaction rate of at a temperature of 1520°C. Both elemental and X-ray diffraction analyses indicated that CeO2 was the end product of the synthesis process. The master alloy does not undergo hydrolysis because CeC2 is synthesized in the liquid phase of iron. It has been established that the technology for producing a cerium carbide alloy involving high-temperature heating in a resistive furnace, enables the production of a material with reproducible properties. [ABSTRACT FROM AUTHOR]

Aluminum‐air batteries (AABs) are regarded as attractive candidates for usage as an electric vehicle power source due to their high theoretical energy density (8100 Wh kg−1), which is considerably higher than that of lithium‐ion batteries. However, AABs have several issues with commercial applications. In this review, we outline the difficulties and most recent developments in AABs technology, including electrolytes and aluminum anodes, as well as their mechanistic understanding. First, the impact of the Al anode and alloying on battery performance is discussed. Then we focus on the impact of electrolytes on battery performances. The possibility of enhancing electrochemical performances by adding inhibitors to electrolytes is also investigated. Additionally, the use of aqueous and non‐aqueous electrolytes in AABs is also discussed. Finally, the challenges and potential future research areas for the advancement of AABs are suggested. [ABSTRACT FROM AUTHOR]

W-Re alloys are one of the most important refractory materials with excellent high-temperature performance that were developed to improve the brittleness of tungsten. In the present work, we firstly summarized the research progress on the preparation and strengthening methods of a W-Re alloy. Then, the strengthening mechanisms of the W-Re alloy were discussed, including the influence of Re, solid solution strengthening, second-phase reinforcement and fine-grain strengthening. The results showed that the softening effect of Re was mainly related to the transformation of the preferred slip plane and the introduction of additional d-valence electrons. Some transition elements and refractory metal elements effectively strengthened the W-Re alloy. Carbides can significantly enhance the high-temperature mechanical properties of W-Re alloys, and the reasons are twofold: one is the interaction between carbides and dislocations, and the other is the synergistic strengthening effect between carbides and Re. The objective of this work was to enhance the comprehension on W-Re alloys and provide future research directions for W-Re alloys. [ABSTRACT FROM AUTHOR]

There is increasing interest in using magnesium (Mg) alloy orthopedic devices because of their mechanical properties and bioresorption potential. Concerns related to their rapid degradation have been issued by developing biodegradable micro- and nanostructured coatings to enhance corrosion resistance and limit the release of hydrogen during degradation. This systematic review based on four databases (PubMed®, Embase, Web of Science™ and ScienceDirect®) aims to present state-of-the-art strategies, approaches and materials used to address the critical factors currently impeding the utilization of Mg alloy devices. Forty studies were selected according to PRISMA guidelines and specific PECO criteria. Risk of bias assessment was conducted using OHAT and SYRCLE tools for in vitro and in vivo studies, respectively. Despite limitations associated with identified bias, the review provides a comprehensive analysis of preclinical in vitro and in vivo studies focused on manufacturing and application of Mg alloys in orthopedics. This attests to the continuous evolution of research related to Mg alloy modifications (e.g., AZ91, LAE442 and WE43) and micro- and nanocoatings (e.g., MAO and MgF2), which are developed to improve the degradation rate required for long-term mechanical resistance to loading and excellent osseointegration with bone tissue, thereby promoting functional bone regeneration. Further research is required to deeply verify the safety and efficacy of Mg alloys. [ABSTRACT FROM AUTHOR]

Purposes In ladle metallurgy, block or whole bag alloy materials and lime are usually added. In recent years, some companies have reported a new process of adding scrap steel to ladle refining furnace. Studying the melting and homogenization mechanism of the above solid substances in the ladle refining process can optimize the refining process and accelerate production rate. Methods Ice sample and ice sphere made by KCl solution were used in the water model experiment separately to study the mechanisms of motion, melting, and mixing of alloy in a 260 t ladle. These two samples were selected to simulate the light and heavy alloys respectively. The effects of factors such as temperature, bottom blowing flow rate, liquid level height, and addition position on the mechanicms were studied. Findings The results show that the melting time of both two ice samples decreases dramatically with increasing temperature. The melting process of light ice sample (ice sphere) can be obviously accelerated by increasing the gas flowrate. When the liquid level is high, i.e. the ratio of liquid level to the diameter is 1.1, the melting time of ice sphere is relative short. The melting of ice sphere can hardly be affected by its adding position. For the heavy ice sample (salt sphere), when added from a position which is far away from the nozzle, it stays at the bottom of the ladle and melts slowly. When the salt sphere is added above the nozzle, the chances of washing by the bubbles from plume area increase and the melting time is shortened. Increasing the gas flow rate can reduce the melting time of the salt sphere, and the liquid level has a negligible effect. When the salt sphere is scoured by the bubbles in plume area, the melting time and mixing time are shortened.

One of the important functions in differential scanning calorimetry (DSC) measurements is to determine the phase transition temperature of materials. In this study, we propose a statistical approach to determine the onset temperature of melting in multiphase alloys using the heating curve of DSC. The melting temperature determined using the extrapolation method is noticeably different from the detectable onset temperature of the reaction. The stationarity of the baseline (of the DSC curve) enables the detection of the onset temperature using statistical method without assumptions of shape of the heat absorption peak; the onset temperature of melting is the point where the baseline loses stationarity which was determined in augmented Dickey-Fuller test in this study. The method was validated by melting a potential eutectic reference alloy (Ag–40Cu in atomic percent), which has an invariant melting temperature at the eutectic composition. The onset temperatures of eutectic and congruent melting of a few binary alloys (Co–13Nb, Ni–41Nb, Ni–45Pd) were determined using this method and compared with the melting temperature obtained using the extrapolation method. The present study provides an improved methodology to evaluate the accurate phase transition temperature of a material. [ABSTRACT FROM AUTHOR]

[Display omitted] While transition metals are useful for activating monopersulfate (MPS) to degrade contaminants, bimetallic alloys exhibit stronger catalytic activities owing to several favorable effects. Therefore, even though Co is an efficient metal for MPS activation, CoFe alloys are even more promising heterogeneous catalysts for MPS activation. Immobilization/embedment of CoFe alloy nanoparticles (NPs) onto hetero-atom-doped carbon matrices appears as a practical strategy for evenly dispersing CoFe NPs and enhancing catalytic activities via interfacial synergies between CoFe and carbon. Herein, N -doped carbon-embedded CoFe alloy (NCCF) is fabricated here to exhibit a unique hollow-engineered nanostructure and the composition of CoFe alloy by using Co-ZIF as a precursor after the facile etching and Fe doping. The Fe dopant embeds CoFe alloy NPs into the hollow-structured N -doped carbon substrate, enabling NCCF to possess the higher mesoscale porosity, active N species as well as more superior electrochemical properties than its analogue without Fe dopants, carbon matrix-supported cobalt (NCCo). Thus, NCCF exhibits a considerably larger activity than NCCo and the benchmark catalyst, Co 3 O 4 NP, for MPS activation to degrade an environmental hormone, dihydroxydiphenyl ketone (DHPK). Besides, NCCF + MPS shows an even lower activation energy for DHPK degradation than literatures, and retains its high efficiency for eliminating DHPK in different water media. DHPK degradation pathway and ecotoxicity assessment are unraveled based on the insights from the computational chemistry, demonstrating that DHPK degradation by NCCF + MPS did not result in the formation of toxic and highly toxic by-products. These features make NCCF a promising heterogeneous catalyst for MPS activation to degrade DHPK. [ABSTRACT FROM AUTHOR]

Uniform PdAuAg alloy nanocrystals with tunable compositions are facilely prepared via a one-pot synthesis. The use of carbon monoxide as the effective agent is crucial to assist the reduction of multiple metallic precursors simultaneously, which is greenly released from in situ thermal decomposition of W(CO)6 in a capped glass vial. The resulting PdAuAg products are featured within the size range of 9.3~11.7 nm and quasi-spherical shape, and their elemental compositions can be readily tuned by varying the molar ratios of corresponding metallic precursors. Interestingly, when the reductant is varied from carbon monoxide to ascorbic acid, the resulting products showed Au@PdAg core-shell elemental distribution, indicating the necessary role of carbon monoxide in dominating the formation of PdAuAg nanocrystals with a fully alloy phase. Using the reduction of 4-nitrophenol as the model reaction, their catalytic properties are evaluated, where the Pd4.1Au3.3Ag2.6 nanocrystals showed the highest apparent rate constant. Results from DFT simulations prove that the 4-nitrophenol adsorption shows a facet and atomic ratio-dependent behavior. The current work provides a feasible strategy to create trimetallic nanocrystals with isotropic shapes and tunable compositions, which could be potentially extended to other metals/alloys. [ABSTRACT FROM AUTHOR]

Corrosion behaviours of Fe–25Cr, Fe–25Cr–2Mn–1Si, Fe–25Cr–20Ni, 310SS, Ni–25Cr, and Ni–25Cr–2Mn–1Si (all in wt%) with and without NaCl–KCl deposits in Ar–60%CO2–20%H2O gas at 750 °C were studied. Without salt deposits, Fe–25Cr performed protectively, while Fe–25Cr–20Ni and Ni–25Cr underwent breakaway oxidation with multilayered scales formed. Adding alloy elements Si + Mn increased the corrosion resistance of all alloys by forming additional Mn-rich oxides and silica. Surface deposits of NaCl–KCl accelerated corrosion, forming porous Fe-rich oxide nodules for Fe–25Cr and thick, porous scales and internal oxidation zones for all other alloys. The protective effect of Si + Mn alloying disappeared in the presence of chlorides. Limited intergranular carbides were observed for all alloys in the gas-only condition. The extent of carburisation increased with the presence of chloride deposits for all Fe-based alloys, but remained unchanged for Ni-based alloys. Corrosion of these alloys at 750 °C is compared with that at 650 °C. The effect of chlorides in volatilising metals at 750 °C is discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiFeRu/C and Ru, Fe-Ni 5 P 4 /C nanofibers as complementary electrocatalyst toward water splitting were synthesized. • The electrolytic cell based NiFeRu/C||Ru, Fe-Ni 5 P 4 /C presents outstanding water splitting activity owing to their complementary activity. • NiFeRu/C||Ru, Fe-Ni 5 P 4 /C requires voltage of 1.569, 1.744 and 1.872 V to achieve 100, 500 and 1000 mA cm−2, respectively. • NiFeRu/C||Ru, Fe-Ni 5 P 4 /C can work stability at 500 mA cm−2 for 100 h. Designing and fabricating highly competent and inexpensive electrocatalysts are highly desirable for application in electrocatalytic water splitting. In this study, we synthesized NiFeRu/C nanofibers and Ru, Fe dual-doped Ni 5 P 4 (Ru, Fe-Ni 5 P 4)/C nanofibers as complementary electrocatalysts for overall water splitting through electrospinning, carbonization, and phosphorization treatment, respectively. The NiFeRu/C nanofibers and Ru, Fe-Ni 5 P 4 /C nanofibers showed high hydrogen evolution reaction and oxygen evolution reaction activity, respectively, due to the presence of numerous exposed active sites and optimized adsorption capacity for the reaction intermediates contributed by the synergistic interaction among different metal components in the electrocatalysts. Hence, the assembled asymmetrical electrolytic cell effectively promoted overall water splitting, requiring a voltage of 1.569, 1.744, and 1.872 V to achieve a current density of 100, 500, and 1,000 mA cm−2, respectively, and it was better than Pt/C||IrO 2. Additionally, the electrolytic cell could work at 500 mA cm−2 for 100 h without any noticeable deterioration in activity, which indicated that it was durable at high current density. In this study, we described a novel method for designing highly efficient electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

Additive manufacturing has been used in art restoration and conservation. Advantages include no direct contact and preserving fragile and rare objects. Long-term stability and aesthetics emphasize materials research. We curate examples highlighting 3D printing and materials in art conservation and creation. This prospective also connects materials choices, 3D digital technologies, and artificial intelligence. An increasing number of modern art pieces are now produced by 3D printing and are in many operations in museums worldwide. Whether creating modern or restoring classical art, a general protocol is now introduced, including future prospective and directions in the field. [ABSTRACT FROM AUTHOR]

The micromagnetic simulation represents the magnetization of a rectangular permalloy sheet with a polycrystalline object. The simulation objects are of four different types. Each has different textures: Gamma-fiber, Cube, Rotate Cube, and Goss texture, respectively. The effective susceptibility, defined as the average ratio of the magnetization to the field during the magnetization reversal process, yields results similar to the experiments in magnetization influenced by the direction of the magnetic field and crystalline texture. [ABSTRACT FROM AUTHOR]

To provide detailed characteristics on the laser beam melting AlSi7Mg0.6 alloy, transmission electron microscopy is required as the microstructure is composed of aluminum cells hardened by nano-sized precipitates encapsulated in a 3D silicon structure. However, sample preparation techniques can cause local temperature variation or irradiation that impact the local microstructure. With various thin foil preparations, we have shown that standard twin jet electropolishing produces thin, well-defined aluminum cells filled with nano-sized precipitates. When ion-based methods are used, due to local heating and irradiation, the nanoprecipitates are significantly altered. Lowering the preparation technique temperature appears to be equivalent to twin jet electropolishing. [ABSTRACT FROM AUTHOR]

Molecular dynamic (MD) simulations were used to investigate the aggregation process of Ti3Al nanoparticles (NPs) of varying sizes. The aggregation behavior of Ti3Al NPs can be divided into four stages: stable contact, slow aggregation, fast aggregation, and uniform diffusion. A liquid bridge was formed in aggregation stage between two NPs and disappears in diffusion stage. The different shrinkage ratio reveals that rapid aggregation, melting, and completion of aggregation do not occur simultaneously. Moreover, the sintering neck is less stable for Ti3Al NPs with a radius of 50 Å due to plastic deformation, resulting in a slow aggregation phase. [ABSTRACT FROM AUTHOR]

The electronic structures of the carbides such as VC, WC, V2C, Mo2C, Cr7C3 and Cr23C6 in Fe-based multi-elements alloy were investigated by first principles. According to the bonding characteristics, the different models were adopted to predict the hardness of these carbides, then, which were compared with experimental. The results show that VC, WC, V2C, Mo2C, Cr7C3 and Cr23C6 are all strong covalent solids and a small metallicity, as well as the contribution of d valence electrons to s-p-d hybridization. Their hardness are 25.80 GPa, 24.28 GPa, 11.52 GPa, 17.06 GPa, 15.07 GPa and 12.78 GPa respectively, which are good agreement with experimental. [ABSTRACT FROM AUTHOR]

Proposed Ti15.4Zr30.2Mn(54.4−x−y)VxNiyCry alloy compositions are characterized by improved characteristics, in particular hydrogen saturation at room temperature and relatively low pressure, which makes them promising for using in hydrogen energy. It established that only part of the nickel introduced into the alloy dissolves in the Laves phase (type C14) and as a result, its phase composition and microstructure change. It was determined that the change in the phase composition of the alloy does not affect the kinetics of the hydrogen absorption process, but leads to a change hydrogen capacity and increase in the temperature at which all hydrogen release. [ABSTRACT FROM AUTHOR]

In this study, we present the fabrication and thermoelectric properties of MgAgSb composites. The fabrication process was based on the concept of nanoparticle engineering. Mg3Sb2 and Ag3Sb nanopowders were first synthesized and subsequently used for MgAgSb formation. The effects of Mg2Cu, Mg2Ni, and Mg2Sn as doping species on thermoelectric properties were studied. Compared with the intrinsic MgAgSb, the electrical conductivity was improved by the Ni and Sn dopants. In contrast, the Cu dopant causes MgAgSb to have a lower ZT. Our experimental results proved that the nanoparticle engineering process can be used for the fabrication of MgAgSb-based thermoelectric composites. [ABSTRACT FROM AUTHOR]

The opto-electronic properties of Ru 2 FeZ (Z = Si , Ge , Sn) full Heusler alloys are explored by using first-principles calculations. The wien2k package with Full potential-linearized augmented plane wave (FP + LAPW) method is used and the exchange–correlation functional is dealt within the framework of Generalized Gradient Approximation amended by Perdew–Burke–Ernzerhof. Electronic band structure and density of states in both spin channels show the overlapping of some valence and conduction bands, which confirms their metallic nature. Optical properties over a wide range of incident photon energy revealed their effectiveness in photo sensors. [ABSTRACT FROM AUTHOR]

Mechanical engineering plays an important role in the design and manufacture of medical devices, implants, prostheses, and other medical equipment, where the machining of bio-compatible materials have a special place. There are a lot of different conventional and non-conventional types of machining of biocompatible materials. One of the most frequently used methods is milling. The first part of this research explores the machining parameters optimization minimizing surface roughness in milling titanium alloy Ti-6Al-4V. A full factorial design involving four factors (cutting speed, feed rate, depth of cut, and the cooling/lubricating method), each having three levels, implies the 81 experimental runs. Using the Taguchi method, the number of experimental runs was reduced from 81 to 27 through an orthogonal design. According to the analysis of variance (ANOVA), the most significant parameter for surface roughness is feed rate. The second part explores the possibilities of using different ML techniques to create a predictive model for average surface roughness using the previously created small datasets. The paper presents a comparative analysis of several commonly used techniques for handling small datasets and regression problems. The best results indicate that the widely used machine learning algorithm Random Forest excels in handling regression problems and small datasets. [ABSTRACT FROM AUTHOR]

Peripheral nerve damage that results in lost segments requires surgery, but currently available hollow scaffolds have limitations that could be overcome by adding internal guidance support. A novel solution is to use filaments of absorbable metals to supply physical support and guidance for nerve regeneration that then safely disappear from the body. Previously, we showed that thin filaments of magnesium metal (Mg) would support nerve regeneration. Here, we tested another absorbable metal, zinc (Zn), using a proprietary zinc alloy with 2% iron (Zn-2%Fe) that was designed to overcome the limitations of both Mg and pure Zn metal. Non-critical-sized gaps in adult rat sciatic nerves were repaired with silicone conduits plus single filaments of Zn-2%Fe, Mg, or no metal, with autografts as controls. After seventeen weeks, all groups showed equal recovery of function and axonal density at the distal end of the conduit. The Zn alloy group showed some improvements in early rat health and recovery of function. The alloy had a greater local accumulation of degradation products and inflammatory cells than Mg; however, both metals had an equally thin capsule (no difference in tissue irritation) and no toxicity or inflammation in neighboring nerve tissues. Therefore, Zn-2%Fe, like Mg, is biocompatible and has great potential for use in nervous tissue regeneration and repair. [ABSTRACT FROM AUTHOR]