Additional Metal Research Articles

Stress-relief annealing friendly Fe-based metallic glass-reinforced Al-Si-Mg-Zr alloy fabricated by laser powder bed fusion

ABSTRACT To enhance the thermal stability of L-PBF Al-Si-Mg alloy, Fe-based metallic glass powder was mixed with Al-Si-Mg-Zr powder to fabricate a novel alloy via L-PBF. The study systematically investigated the effects of process parameters on processability and the impact of stress-relief annealing (300 ∘ C–2h) on the microstructure and mechanical properties. Results showed that metallic glass addition improved surface quality. Plastic deformation was analysed using finite element and molecular dynamics methods. The as-built alloy had a cellular substructure with Al 3 Zr, Si, AlFeMgSi, and AlFeSi phases. Si nanoparticles and stacking faults were observed in α-Al cells. The as-built samples had yield strength (YS) of 249±4 MPa, ultimate tensile strength (UTS) of 434±6 MPa, and 6.3±0.3% elongation. Post-annealing, the alloy retained high strength and plasticity with YS of 255±3 MPa, UTS of 449±15 MPa, and 7.2±0.3% elongation, outperforming similar L-PBF Al-Si and Al-Si-Mg alloys.

Comparison of the effect of gaseous and metallic additives on ultrathin Ag layer formation: An experimental and numerical investigation

Ultrathin Ag layers are promising for optoelectronic applications, however, the inherently poor wettability of Ag on oxide substrates such as SiOx poses a significant challenge. Current techniques for resolving this issue often introduce trace amounts of metallic or gaseous additives during Ag growth. Previous studies have not thoroughly compared the influence of metallic and gaseous additives on the wetting and optoelectrical performance of Ag. Even though these additives certainly improve Ag wetting, existing information on their effectiveness is inconsistent. In this study, we aimed to identify the most effective additive by investigating the impact of the O, N, Cu, and Zn additives on Ag wetting. We combined experimental and computational investigations to reveal the ways these additives at the Ag surface and/or the Ag − SiOx interface reduce the cohesive energy of the Ag layers, thereby determining the Ag wetting behavior. Consequently, our findings suggest that O is the most effective additive for improving the optoelectrical properties of the Ag layers owing to its ability to enhance Ag wettability and optoelectrical performance. This conclusion challenges conventional practices, heavily relying on metallic additives and Cu in particular. Our study provides valuable insights into the optimization of ultrathin Ag layers for optoelectronic applications.

Room temperature n-butanol detection by Ag-modified In2O3 gas sensor with UV excitation

The aim of this study is to develop a sensor for the detection of n-butanol gas at room temperature, which in turn facilitates sensor integration. To this end, porous In2O3 nanosheets were prepared in this experiment, along with noble metal Ag modification and UV excitation, to achieve effective monitoring of low concentrations of n-butanol at room temperature. The material composition and structure were analyzed by various analysis techniques. The addition of precious metals promotes the absorption of UV light by the material. The n-butanol gas sensitivity test was completed on individual samples under 365 nm UV. The response of 5wt% Ag/In2O3 to 10 ppm n-butanol under UV irradiation reaches 127.5% at room temperature, which is twice as much as pure In2O3. The sensor showed a well regular answer at different concentrations of n-butanol. This paper also discusses the sensing mechanism for the improved gas-sensitive behavior of Ag/In2O3, which mainly benefits from the chemical and electron sensitizing of Ag. The results show that the Ag/In2O3 material excited by ultraviolet light in this paper lays a certain foundation for the preparation of room temperature n-butanol gas sensor.

Effect of sludge-based additive on particulate matter emission during the combustion of agricultural biomass pellet

In this study, the effects of a sludge-based additive on particulate matter emission during the cornstalk pellet combustion were investigated using a vertical fixed bed reactor combined with a Dekati low pressure impactor (DLPI). It was found that the PM1 and total PM10 yields from the cornstalk pellet combustion were much higher than those from the individual combustion of sludge-based additive. With the addition of sludge-based additive, the alkali and alkaline earth metals (AAEMs) in biomass would react with the Al/Si-containing and P-containing inorganic minerals in sludge-based additive to form various aluminosilicates, silicates, and K-Ca-P compounds, which could enhance the potassium fixation and retain it in the coarse particles, such as fly ash and residual ash. The PM1 and total PM10 yields from the composite pellet combustion could be effectively reduced by 62%, with the mixing ratio of sludge-based additive increasing to 75%. The mixing ratio of sludge-based additive showed a positive synergistic effect in reducing the emission of PM and a mixing ratio of <30% was recommended based on comprehensive considerations to produce relatively high-quality pellet fuel with respect to good heating value and low ash content and PM emission in later combustion application.

Solar Light Elimination of Bacteria, Yeast and Organic Pollutants by Effective Photocatalysts Based on Ag/Cr-TiO2 and Pd/Cr-TiO2.

This study focused on searching for more effective nanomaterials for environmental remediation and health protection; thus, coliform bacteria, yeast and the organic food dye sunset yellow were selected as target pollutants to be eliminated under solar light by Ag/Cr-TiO2 and Pd/Cr-TiO2. Firstly, Cr3+ was in situ incorporated into the anatase crystalline lattice by the sol-gel method; then, Ag or Pd nanoparticles were deposited on Cr-TiO2 by chemical photoreduction. The scientific challenge addressed by the development of these composites was to analyse the recovery of Cr, to be employed in photocatalyst formulation and the enhancement of the TiO2 photocatalytic activity by addition of other noble metals. By extensive characterization, it was found that after TiO2 doping with chromium, the parameters of the crystal lattice slightly increased, due to the incorporation of Cr ions into the lattice. The TiO2 band gap decreased after Cr addition, but an increase in the optical absorptions towards the visible region after noble metals deposition was also observed, which was dependent of the Ag or Pd loading. Generally, it was observed that the noble metals type is a factor that strongly influenced the effectiveness of the photocatalysts concerning each substrate studied. Thus, by using Ag(0.1%)/Cr-TiO2, the complete elimination of E. coli from samples of water coming from a highly polluted river was achieved. Pd(0.5%)/Cr-TiO2 showed the highest efficiency in the elimination of S. cerevisiae from a lab prepared strain. On the other hand, the Pd(0.1%)/Cr-TiO2 sample shows the highest dye degradation rate, achieving 92% of TOC removal after 180 min.

Assessment of the adaptive ability of regenerant and original oat genotypes to soil stressors

The aim of the research is a comparative analysis of the response to soil stressors according to the biochemical and productive characteristics of the initial genotypes of oats (line 2h15) and regenerative forms (RA, RAAl, RAMn, RACd) in the framework of evaluating the effectiveness of applied cell selection schemes. In the vegetation experiment, the effect of soil stressors on plants was studied – increased acidity (pH = 4.3), toxicity of manganese ions (65.2 mg/kg, pH = 5.2) and cadmium (2.87 mg/kg, pH = 5.2). The Arkhan variety was used as a standard. The control was soil with a neutral pH (7.2). Regenerants were previously obtained in vitro on artificial media without stress (RA) and with selective agents: alumina acid (RAAl), increased Mn2+ (RAMn) and Cd2+ (RACd). On soil with stressors, the pigment content in regenerant leaves exceeded the baseline values by 1.4…1.6 times. In control, the differences between RA and the baseline are unreliable. All regenerative lines, regardless of growing conditions, were characterized by significantly lower levels of polyphenols in grain (11.2…12.4 mg/g dry weight), compared with the baseline and the standard by 1.2…1.3 times. On backgrounds with artificial addition of metals, an excess of the manganese level in the grain was noted: 1.7 times in RAMn (256.1 mg/kg), compared with the baseline, and there were no differences between them in the cadmium content in RACd (1.82…1.67 mg/kg). On the control background, RA and the baseline significantly lagged behind the standard in terms of grain weight from the plant: in regenerants – 1.29 g; baseline – 1.38 g; standard – 1.65 g. With increased acidity and cadmium, all genotypes decreased productivity relative to the control, but to a lesser extent regenerants (1.6 and 1.4 times, respectively), the baseline – 2.8 and 2 times, the standard – 2.4 and 1.9 times.

Effect of Addition of Rare Earth Metal (Ce) on the Microstructure, Mechanical Properties and Corrosion Behavior of NiTi Alloys

Effect of Addition of Rare Earth Metal (Ce) on the Microstructure, Mechanical Properties and Corrosion Behavior of NiTi Alloys

An Electron Bridge of Shared Atoms Mediated Cs3Bi2Br9/Bi2WO6 Z‐Scheme Heterojunction for Photocatalytic CO2 Reduction

AbstractConverting clean solar energy into chemical energy through artificial photosynthesis is an effective solution to solve the energy and environmental issues. Here, we report a Cs3Bi2Br9/Bi2WO6 (CBB/BWO) Z‐scheme heterojunction constructed via electrostatic self‐assembly, which facilitates efficient separation of photogenerated carriers and ensures the corresponding redox capacity of both components. By sharing Bi atoms, a Br−Bi−O bond is established between CBB and BWO, serving as an “electron bridge”. The electrons generated by BWO are efficiently channeled to CBB through the heterojunction‐formed “electron bridge”, thereby achieving effective photocatalytic CO2 reduction. Under simulated sunlight conditions, it exhibits the highest CO yield of 72.52 μmol g−1 (without the addition of any precious metal, photosensitizers or sacrifices), which is approximately 7‐fold and 18‐fold greater than that of pure CBB and BWO, respectively. This work provides a more profound comprehension of the regulation of electron transfer through interfacial chemical bonds, thereby proposing a promising strategy for the development of efficient heterojunction photocatalysts for CO2 photoreduction.

TEMPO as Hydrogen Atom Transfer Catalyst in Enhancing Iminyl Radical Cyclization of O-Acetyl Oxime toward Phenanthridines and Isoquinolines.

Herein, we present a strategy for promoting the cyclization of ortho-aryl or ortho alkenyl arylketone oxime ethers C-N bonds using TEMPO as a direct hydrogen atom transfer (HAT) catalyst. The reaction employs a green solvent and requires no introduction of metal additives. It only needs catalytic amount of TEMPO to drive the reaction. Gram-scale reaction yields the corresponding products with satisfactory yields, providing a novel and efficient method for the synthesis of phenanthridine and isoquinoline derivatives.

Effect of transition and alkali metals on Mo2C/Al2O3 catalysts for syngas to higher alcohols

Direct production of higher alcohols remains a great challenge in syngas conversion process. Herein, MMo2C/Al2O3 and KMMo2C/Al2O3 catalysts promoted by different transition metals M (M=Co, Fe, Cu, Ni, Zn, Nb) and alkali metal (K) were prepared by impregnation method to investigate the effect on CO hydrogenation to higher alcohols under milder reaction conditions (300°C, 3.0 MPa). The catalysts were characterized with XRD, H2-TPR, and XPS. It was found that the addition of transition metals and K resulted in the decrease of low-valent Mo species on the catalyst surface, which facilitated the generation of Mo4+ during the reaction. Increase in Mo4+ content facilitates the conversion of CO to CO*, which provides more CO insertion sites for the generation of alcohols. Moreover, the introduction of K also enhances the interaction of transition metals with Mo, which accelerates the formation of alcohols in the reaction. Meanwhile, the transition metal and Mo2C work together to promote the dissociative adsorption of CO. The production of higher alcohols is facilitated by the synergistic effect of the two mentioned above. Overall, the KCoMo/Al2O3 and KFeMo/Al2O3 catalysts exhibited high selectivity for higher alcohols, reaching 73.9 % and 71.3 % for C2+OH in the alcohol products, respectively. CO conversion of KFeMo/Al2O3 catalyst can reach 84.9 % with excellent stability in the reaction. Moreover, the possible pathways of the reaction were obtained by in-situ DRIFT characterization.

A comprehensive study of radiation shielding parameters of chalcogens-rich quaternary alloys for nuclear waste management

The current study examines the impact of metal additives on the shielding characteristics of Se76Te20Sn2M2 (where M = Ge, In, Sb, and Pb). These glasses are useful as shielding materials against high-energy radiation, such as X-rays and ϒ-rays, because these glasses have better values of shielding parameters compared to other potential candidates in the race for nuclear safety applications. To this end, we have calculated various radiation-related protection parameters using an online application called Phy-X/PSD. Using this program, we have estimated a complete list of radiation shielding parameters. The impact of the fourth element M (M = Ge, In, Sb, and Pb) on these parameters is also discussed.The maximum mass attenuation coefficient (MAC) was recorded at a photon energy of 15 keV for the incorporation of lead. Half-value layer (HVL) values peaked at 6 MeV and it attained its maximum value for germanium. The highest and lowest values of the linear attenuation coefficients (LAC) were obtained for Se76Te20Sn2Pb2 and Se76Te20Sn2Ge2 alloys respectively. Notably, the Se76Te20Sn2Pb2 alloy exhibited the highest values of effective atomic number (Zeff), electron density (Neff), atomic cross-section (ACS), and electronic cross-section (ECS), indicating superior shielding performance. Conversely, energy absorption buildup factors (EABF) and exposure buildup factors (EBF) were highest for Se76Te20Sn2Ge2 alloy. Neutron attenuation was most effective in the Se76Te20Sn2In2 and Se76Te20Sn2Pb2 compositions. Overall, the incorporation of lead in the parent glass demonstrated superior shielding capability compared to the other compositions studied.

Liquid metal-enhanced composite conductive ink with improved electrical stability and durability for flexible electronics

For flexible electronics, conductive ink is a critical material with diverse applications. However, conventional inks, like those based on nano-silver, are expensive and result in printed patterns with limited conductivity stability. To address these limitations and enhance overall electrical performance, stability, and durability, this study developed a novel composite conductive ink incorporating liquid metal and silver microparticles. We fabricated conductive patterns and extensively investigated the sintering process, focusing on how liquid metal content and sintering techniques affect the resulting patterns' electrical performance and stability. Our findings reveal that incorporating liquid metal introduces a slight trade-off in the initial conductivity. However, subsequent thermal and hot-press sintering treatments significantly improve conductivity, with hot-press sintering leading to the most pronounced enhancement. Furthermore, the addition of liquid metal substantially bolsters the electrical stability of the patterns. Notably, conductive patterns fabricated using a 1:1 mass ratio of the ink exhibit ∆R/R0 values of only 1.72 and 0.432 after 5000 bending cycles, following thermal and hot-press sintering, respectively. This highlights the significant improvement in electrical stability and durability achieved by incorporating liquid metal into the conductive ink.

A Black State from Reversible Copper Electrodeposition without Metal Additives

A Black State from Reversible Copper Electrodeposition without Metal Additives

Application of metal additive testing and thermal conductivity technology in optimizing product appearance design in intelligent manufacturing industry

Metal additive manufacturing technology has the advantages of rapid manufacturing and personalized production, but due to the complexity of the manufacturing process and differences in material characteristics, products made with metal additives often have appearance defects and process performance issues. Therefore, the purpose of this study is to explore the application of metal additive detection technology in product appearance design and process performance optimization. This study proposes a comprehensive detection and optimization method that utilizes non-destructive testing techniques to comprehensively inspect metal components. By identifying and locating these issues, the quality status of the components can be accurately understood. Based on the test results, a series of appropriate optimization measures have been taken to improve the appearance and process performance of the product, adjust process parameters, improve the forming quality and surface smoothness of the components, thereby achieving better appearance effects. Metal additive testing technology can effectively detect and locate appearance defects in products, and by optimizing process parameters and material selection, it can significantly improve the appearance quality and process performance of products, providing support for improving the reliability and production efficiency of industrial manufacturing.

Influence of TiC and Ni addition on densification and mechanical properties of microwave sintered ZrB2 based composites

The effects of TiC (10–30 vol%) and Ni (1–2 vol%) incorporation on densification, microstructural evolution and mechanical properties of microwave sintered ZrB2 matrix-based composites were investigated in the present study. The findings reveal that TiC addition significantly improves the densification of ZrB2 based composites, while the inclusion of Ni further improves densification of ZrB2–20 vol% TiC composite by reducing porosity and restricting the grain growth of both ZrB2 and TiC phases. Additionally, the highest Vickers hardness of 22.25 ± 1.33 GPa and compressive strength of 1556.2 ± 40.17 MPa were obtained for the ZrB2–20 vol% TiC composite due to lower porosity, lower grain size and higher TiC diffusion in the ZrB2 matrix. The fracture toughness enhanced with TiC and Ni addition and the maximum fracture toughness was observed as 6.66 ± 0.47 MPa.m0.5 along with the highest critical energy release rate of 95.16 ± 11.68 J/m2 for the ZrB2–20 vol% TiC-2 vol% Ni composite owing to the activation of toughening mechanisms like crack bridging, crack deflection and open pores as crack deflectors. Nanoindentation studies revealed significant improvements in elastic modulus and stiffness with the addition of TiC. The maximum elastic modulus and stiffness were observed as 482.91 ± 36.36 GPa and 237.24 ± 20.28 μN/nm for ZrB2–20 vol% TiC composite. The study highlights the potential of incorporating metallic additives with secondary reinforcements to enhance the mechanical properties and microstructures of ZrB2 matrix, making them potential materials for high-temperature applications such as control surfaces, nose caps and leading edges of supersonic aircrafts.

Simultaneous removal of cadmium and arsenic co-contamination by iron/sulfur-modified zeolites combined with sulfate-reducing bacteria

As common water environmental pollutants, the problem of co-contamination of cadmium (Cd) and arsenic (As) has aroused widespread concern. To solve the problem, microbial remediation technology, represented by its high efficiency, cheapness, and stability, has gained increased attention. In this study, we conducted an investigation on the efficacy of Fe/S modified zeolites (Z-FeOS) and sulfate-reducing bacteria (SRB) in removing Cd(II) and As(III) contained wastewater. The Cd(II) and As(III) removal efficacy of Z-FeOS+SRB were investigated by differing the addition time of heavy metals, SRB dosage, Z-FeOS dosage, pH, and reaction time. The produced precipitates were characterized to elucidate the removal mechanism. The results showed that the removal efficiency of Z-FeOS+SRB was much better than that of separate Z-FeOS and SRB treatments. At the Cd(II) and As(III) concentrations of 10 and 5 mg/L, respectively, the ideal removal conditions of Z-FeOS+SRB were post-heavy metal addition time of 48 h, SRB dosage of 20 % v/v, Z-FeOS dosage of 0.7 % m/v, pH 8.0, and reaction time of 168 h. Under these conditions, Cd(II) and As(III) removal efficiencies were 93.4 % and 39.9 %, respectively. The characterization results illustrated the existence of CdS and As2S3 in the precipitation products, suggesting that Cd and As were removed through sorption/co-precipitation in these forms. This study demonstrated the application potential of Z-FeOS+SRB in the bioremediation of Cd and As from environments.

Fabrication and characterization of HfCZrCTiC composites: role of carbonaceous and metallic additives

Fabrication and characterization of HfCZrCTiC composites: role of carbonaceous and metallic additives

Regulation of sol-gel derived Cu-M/Al2O3 by metal additives for the selective catalytic transfer hydrogenation of furfural

Furfural is an indispensable platform compound derived from biomass resource and can be hydrogenated to produce a series of high value-added chemicals. In order to overcome the disadvantages of low selectivity and poor stability during furfural hydrogenation, design of promising Cu catalysts with well-disentangled catalytic theory becomes a hot topic. In this work, a series of Cu-M/Al2O3 (M=Fe, Co, Ni, Ce) catalysts were prepared by sol-gel method to make a uniform ternary metal composition. Distinctive product distribution for the catalytic transfer hydrogenation of furfural was obtained depending on the specific Cu-M/Al2O3 system. Among them, the Cu-Fe/Al2O3 displayed superior selectivity of 2-methylfuran compared to any other catalysts. The introduced metal additive acted as the electron donor to regulate the surface dispersion of Cu species. Higher percentage of surface Cu0+Cu+ species were formed on Cu-Ce/Al2O3 and Cu-Fe/Al2O3, accounting for the much lower activation energy and better dissociation ability for isoproponal. If Cu-Ni/Al2O3 or Cu-Ce/Al2O3 was used as the catalyst, hydrogenation happened on the furan ring. Whilst Cu-Co/Al2O3 was more preferentially used to produce 2-pentanol and 2-pentanone, with large amount of copper species in oxidative states. The yield of 2-MF reached 84 % at 220 ºC in N2 at ordinary pressure by Cu-Fe/Al2O3 with the specific rate of 106.8 mmolFAL·gCu−1·h−1.

Appraisement and categorization of compostable and non-compostable plastic bags using HHXRF spectrophotometer, A study on brands in Islamabad

Plastic bags are polymers usually composed of polypropylene, polyethylene and polystyrene. Rapid development in the industrial sector manufacturing plastic bags is imposing tremendous side effects on human health and the environment. Conventional plastic bags are made from recycled or first use, but authorities restricted lightweight plastic bags (thickness of &lt;50μm) with compostable material. This study examines the degradation of plastic bags collected from the markets of different sectors of Islamabad. Many samples (~100) were gathered from the public market. Using a Hands Held X-Ray Fluorescent (HHXRF) spectrophotometer and the standard approach, the study confirmed the proportions, amounts, and patterns of several heavy metals (additives) utilized in the production of both types of bags. The result showed Titanium (Ti), Copper (Cu) and Calcium (Ca) were used in massive amounts, other carcinogenic metals i.e., Mercury (Hg), Arsenic (Ar), Chromium (Cr), Lead (Pb) and Cadmium (Cd) were also detected. Long term exposure to this metal can disrupt living cells. We concluded that because of the photolytic qualities of the additives used in degradable plastic bags when the linkages of polymers are generated, degradable plastic bags may be more dangerous than non-degradable plastic bags.

Effect of the Addition of Platinum Group Metals on Mechanical Properties of Cemented Carbide

Effect of the Addition of Platinum Group Metals on Mechanical Properties of Cemented Carbide