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Purpose: This study aims to investigate the corrosion behavior of cold-rolled Fe35Ni20Cr12Mn(28-x)Alx high-entropy alloys (HEAs) using the potentiodynamic polarization technique in 1 M H2SO4 acid. Additionally, the influence of molybdenum (Mo) additions as inhibitors and the effect of variations in cold rolling reduction ratios and Al content on corrosion behavior are examined. Design/methodology/approach: Two cold rolling reduction ratios, namely, 50% (R50) and 90% (R90), were examined for the cold-rolled Fe35Ni20Cr12Mn28Al5 (Al5) and Fe35Ni20Cr12Mn23Al10 (Al10) HEAs. Mo inhibitor additions were introduced at varying concentrations of 0.3, 0.6 and 0.9 Wt.%. The potentiodynamic polarization technique was used to evaluate the corrosion rates (CRs) under different experimental conditions. Findings: The results indicate that the addition of 0.3 Wt.% Mo in 1 M H2SO4 yielded the lowest CR for both R50 and R90, irrespective of the Al content in the HEAs. However, the highest CR was observed at 0.6 Wt.% Mo addition. Furthermore, increasing the concentration of Al resulted in a corresponding rise in the CR. Comparatively, the CR decreased significantly when the cold rolling reduction ratio increased from R50 to R90. Originality/value: This research provides valuable insights into the intricate relationship between Mo inhibitors, cold rolling reduction ratio, Al content and the resulting corrosion behavior of Fe35Ni20Cr12Mn(28-x)Alx HEAs. The comprehensive analysis of corroded HEAs, including surface morphology, compositions and elemental distribution mapping, contributes to the understanding of the corrosion mechanisms and offers potential strategies for enhancing the corrosion behavior of HEAs. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) has garnered significant attention because it is featured by the conversion of the two most representative greenhouse gases CH4 and CO2 into syngas composed of H2 and CO as target products. In our previous studies, we demonstrated the high catalytic activity and stability in DRM for the nickel silicate BEA-type zeolite (Ni-BEA) catalyst synthesized by interzeolite transformation. Here, the molybdenum modified Mo/Ni-BEA was prepared by deposition precipitation method on Ni-BEA, and its DRM activity was evaluated. Compared to the bare Ni-BEA, the modified Mo/Ni-BEA showed the more enhanced activity and stability with low carbon deposition, e.g., 9% lower coke content after 12 h on stream under harsh DRM reaction conditions, because of the promoter effect of molybdenum. Furthermore, Mo/Ni-BEA exhibited the stronger stability, i.e., both the deactivation rates for CH4 and CO2 were less than half compared to those of Ni-BEA, in a long-term DRM test for 55 h. To investigate the role of molybdenum as a promoter, the catalysts before and after reactions were analyzed through various characterization methods. [ABSTRACT FROM AUTHOR]

For the determination of tin(II) traces, an extractive spectrophotometric approach is devised. The applied method serves a powerful tool for determination of tin(II), involves the formation of yellow colored complex after the binding of 6-bromo-3-hydroxy-2-(5-methylfuran-2-yl)-4H-chromen-4-one (BHMF) and tin(II) in 1:2 stiochiometry in a slightly acidic medium (HCl). The complex shows absorbance at 434 nm with respect of the blank reagent. The outcomes of spectral investigation for complexation showed a Beer's range of 0–1.3 μg Sn mL−1, molar absorptivity, specific absorptivity and Sandell's complex sensitivity are 9.291 × 104 L mol−1 cm−1, 0.490 mL g−1 cm−1 and 0.002040 μg cm−2 at 434 nm that was stable for two days. The interferences study results showed that this method is free from interferences, when tested with metal ions including Ag, Be, Bi, Ca, Cd, Ce, Co, Hg, Mo, Re, Pt, Se,Ti, U, V, W and other common cations, anions, and complexing agents. The applied method is quite simple, highly selective, and sensitive with good re-producibility. This method has been satisfactorily by utilizing the proposed procedure, and its applicability has been tested by analyzing synthetic samples and an alloy sample of gunmetal. The procedure assumes this because of the scarcity of better methods for determining tin(II). The results are in good agreement with the certified value. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mo, W doped Co 2 P/NF electrodes were designed for HER and GOR. • High catalytic efficiencies for HER, GOR were fulfilled. • The surface evolved CoO 2 was the genuine catalytic species for GOR. • H 2 and formate were coproduced by energy-saving glycerol electrolysis. H 2 and formate are important energy carriers in fuel-cells and feedstocks in chemical industry. The hydrogen evolution reaction (HER) coupling with electro-oxidative cleavage of thermodynamically favorable polyols is a promising way to coproduce H 2 and formate via electrochemical means, highly active catalysts for HER and electrooxidative cleavage of polycols are the key to achieve such a goal. Herein, molybdenum (Mo), tungsten (W) doped cobalt phosphides (Co 2 P) deposited onto nickel foam (NF) substrate, denoted as Mo-Co 2 P/NF and W-Co 2 P/NF, respectively, were investigated as catalytic electrodes for HER and electrochemical glycerol oxidation reaction (GOR) to yield H 2 and formate. The W-Co 2 P/NF electrode exhibited low overpotential (η) of 113 mV to attain a current density (J) of −100 mA cm−2 for HER, while the Mo-Co 2 P/NF electrode demonstrated high GOR efficiency for selective production of formate. In situ Raman and infrared spectroscopic characterizations revealed that the evolved CoO 2 from Co 2 P is the genuine catalytic sites for GOR. The asymmetric electrolyzer based on W-Co 2 P/NF cathode and Mo-Co 2 P/NF anode delivered a J = 100 mA cm−2 at 1.8 V voltage for glycerol electrolysis, which led to 18.2 % reduced electricity consumption relative to water electrolysis. This work highlights the potential of heteroelement doped phosphide in catalytic performances for HER and GOR, and opens up new avenue to coproduce more widespread commodity chemicals via gentle and sustainable electrocatalytic means. [ABSTRACT FROM AUTHOR]

MoS2 and WS2 are spotlighted as fungible materials of graphene that can be used in electronic devices owing to being semiconductors with indirect and direct band gaps. Precursors (Mo(NtBu)2(StBu)2 (1), W(NtBu)2(StBu)2 (2)) suitable for the deposition of these materials were synthesized and characterized. The molecular structures of 1 and 2 exhibit a tetrahedral geometry according to single‐crystal x‐ray crystallography. Thermogravimetric analyses of 1 and 2 showed two‐step weight loss. The residues from each step of 1 were MoS3 and MoS2, and these results were consistent with the subsequent deposition results of 1. We successfully established a PEALD‐MoS2 process using 1 and H2S plasma as the precursor and reactant, respectively, at relatively low temperatures of 150–300 °C without any post‐sulfurization process. A temperature‐dependent selective deposition of MoSx phases was observed with the growth of amorphous MoS3 films (150–200 °C), and crystalline MoS2 films (250–350 °C). [ABSTRACT FROM AUTHOR]

This article provides an overview of the powder metallurgy (PM) industry in North America in 2024. The automotive market is a major driver of the industry, with a shift towards hybrid and plug-in hybrid electric vehicles (HEV and PHEV) due to environmental concerns. Lightweight metals like aluminum, magnesium, and titanium are expected to increase in use, but ferrous alloys will remain the most used due to their strength and cost-effectiveness. Other growth opportunities for PM include energy, aerospace, medical, electrical, defense, and consumer products. Metal powder shipments in 2023 decreased overall, with iron powder shipments down by over 10%. However, there is optimism for the future of PM in various industries, including AM and MIM. The P&S parts makers in the automotive industry faced challenges, but new opportunities are emerging with the shift to electric motors. The metal additive manufacturing (AM) sector is dependent on advancements in materials and manufacturing processes, with new materials and equipment being developed. Overall, the PM industry in North America is facing both challenges and opportunities in various sectors. The article also discusses the use of advanced simulation software in metal AM parts, the standard test methods issued by the Association for Metal Additive Manufacturing (AMAM), the healthy state of the metal injection molding (MIM) industry, the impact of the Russian-Ukrainian war on tungsten powder demand, and the need for investment in R&D and the development of people to advance PM technology. [Extracted from the article]

The structure and mechanical properties of thick vacuum condensates of molybdenum and dispersion-strengthened alloys of the Mo–ZrO2 system with a thickness of 0.8…l.2 mm produced by electron beam evaporation of chosen components with subsequent condensation of their vapor phase onto flat molybdenum substrates was investigated. It was shown that the structure features and the level of condensate strength depend on the substrate temperature and volumetric content of the strengthening phase for two-phased condensates. [ABSTRACT FROM AUTHOR]

Structural, electronic, optical, thermoelectric ,and elastic properties of Mo- and W-based group-V compounds, TMX (TM = Mo and W; X = N, P, and As) have been studied by using the full-potential linear augmented plane wave method. Local spin density approximation (LSDA) has been used for exchange–correlation potentials. Pressure-dependent lattice constants and bulk moduli have been obtained using LSDA. Volume optimization, with and without spin-polarization, reveal that the WC-type hexagonal phase (MoN, MoP, and WN) and MoAs and WP in MnP-type orthorhombic phase are energetically stable in a non-magnetic phase. The electronic properties show that all these materials are metallic in nature, while the optical properties showed high reflectivity and low transmission. The thermoelectric properties have also been elaborated, and, as these materials have zero band gap values, they showed high thermal conductivity at high temperatures with low Seebeck and almost constant electrical conductivity. Moreover, the elastic properties of these two phases are surprising with their high bulk and shear moduli. All the materials fall in the category of super-hard materials with ductile and brittle characteristics. [ABSTRACT FROM AUTHOR]

We developed a molybdenum (Mo)‐doped cobalt (Co)‐heterostructure embedded on a phosphorous (P) and nitrogen (N) dual‐doped porous carbon which exhibits an intrinsic electronic transport channel of Co to Mo and P. The P,Mo,O−Co/PNC/NF (NF=Nickel foam) electrode offers 335 mV overpotential at 10 mA cm−2 in OER as compared with PMA‐ZIF67‐NC/NF and ZIF67‐NC/NF electrode with an overpotential of 357 and 373 mV respectively. Linear sweep voltammetry (LSV) of overall water splitting (OWS) supports that the current density gradually increased at a cell potential of 1.6 V with a maximum of 40 mA with a corresponding cell potential of 1.79 V at a current density of 10 mA cm−2. Density functional theory (DFT) calculations for water adsorption on optimized [111] surface of Co, CoMo, and CoMoP2 with adsorbed H2O and corresponding lattice determine the electron density difference of [111] surface with adsorbed H2O for Eads (eV) 4.23 corresponds to adsorption energy for CoMoP2. XANE‐EXAFS spectroscopy of P,Mo,O−Co/PNC at Co K edge and Mo K edge suggests the presence of higher valence of both Cox+ and Mox+ without metallic Co and Mo and Co−P and Mo−P bonds as major structural units due to phosphidation as determined by R‐space FT‐EXAFS spectra. [ABSTRACT FROM AUTHOR]

On the basis of previous work, this paper systematically investigates the influence parameters and leaching kinetics of the ammonia leaching process of molybdenum calcine obtained by microwave roasting. The conditions of the ammonia leaching process of calcined molybdenum were optimized by changing the parameters of ammonia concentration, solid–liquid ratio, and leaching temperature. The results show that, when the concentration of ammonia was 25%, the mass of calcined molybdenum and the volume of ammonia were 1/2 g/ml, the leaching temperature was 75°C, and the leaching time was 60 min, the leaching efficiency of molybdenum can reach 91.74%, and the content of ammonium molybdate in the leaching product was 97.23 wt.%. In the leaching process, MoO3 in the solid phase is dissolved by ammonia to form ammonium molybdate, which conforms to the shrinking core model. The activation energy of the reaction is 57.8 kJ/mol and the rate control step is determined by the mixed model of chemical reaction and product layer diffusion. The apparent rate equation is expressed as: 1 3 ln 1 - x + 1 - x - 1 3 - 1 = 14.97 ω ammonia 2.004 (L / S) - 2.44 e - 57800 RT t . [ABSTRACT FROM AUTHOR]

Purpose: Impacts of mineral resource use on the availability of resources can be assessed using a broad range of methods. Until recently, life cycle inventory (LCI) and life cycle impact assessment (LCIA) models have been based on resource extraction. As extracted resources are not necessarily "lost" for future use, recent methodological developments have shifted the focus from resource extraction to resource dissipation. This paper aims at reviewing dissipation-based LCIA methods, testing them in a case study, analyzing potential implications for the product environmental footprint (PEF), and providing recommendations for future method development. Method: Five recently developed LCIA methods have been reviewed and compared based on 22 criteria, such as the forms and time horizons of dissipation considered, scientific publication, and number of characterization factors (CFs). Additionally, the abiotic depletion potential (ADP) method has been included to serve as a non-dissipation-based reference. All methods are tested in a case study on a theoretical product, designed solely for demonstration purposes, and consisting of 1 kg of the metals aluminum, cobalt, copper, molybdenum, nickel, and zinc. In addition to the absolute LCIA results, the contributions of metal production stages and individual resource extractions/emissions have been investigated. Finally, normalization and weighting have been carried out to analyze consequences of replacing ADP with the new dissipation-based methods in the context of PEF. Results and discussion: Most recently developed LCIA methods take a long-term perspective, cover emissions of resources to the environment (and partly technosphere), and vary in the number of CFs and resources covered. The case study results obtained by ADP are dominated by the molybdenum dataset; the results of the dissipation-based LCIA methods are strongly influenced by the cobalt dataset. All results are strongly sensitive to the LCI database used (ecoinvent or GaBi). Normalization and weighting revealed that the mineral resource use impact result dominates the aggregated PEF score (57%), when using the currently recommended ADP model. Shifting from the resource extraction-based ADP to dissipation-based models can reduce the contribution to 23% or < 1% depending on the method. Conclusion: The development of methods addressing mineral resource use in LCIA has shifted from resource extraction to dissipation. The analyzed methods are applicable and lead to different findings than the extraction-based ADP. Using the newly developed methods in the context of PEF would significantly change the relevance of the mineral resource use impact category in comparison to other environmental impacts. [ABSTRACT FROM AUTHOR]

We present measurements of the 2p-3d transition opacity of a hot molybdenum–scandium sample with nearly half-vacant molybdenum M-shell configurations. A plastic-tamped molybdenum–scandium foil sample is radiatively heated to high temperature in a compact D-shaped gold Hohlraum driven by ∼30 kJ laser energy at the SG-100 kJ laser facility. X rays transmitted through the molybdenum and scandium plasmas are diffracted by crystals and finally recorded by image plates. The electron temperatures in the sample in particular spatial and temporal zones are determined by the K-shell absorption of the scandium plasma. A combination of the IRAD3D view factor code and the MULTI hydrodynamic code is used to simulate the spatial distribution and temporal behavior of the sample temperature and density. The inferred temperature in the molybdenum plasma reaches a average of 138 ± 11 eV. A detailed configuration-accounting calculation of the n = 2–3 transition absorption of the molybdenum plasma is compared with experimental measurements and quite good agreement is found. The present measurements provide an opportunity to test opacity models for complicated M-shell configurations. [ABSTRACT FROM AUTHOR]

Manufacturing titanium alloys with simultaneous enhancement in strength and ductility has motivated extensive research into various strategies for regulating the arrangement and texture of α and β phases. The present study explores a novel α + β titanium alloy, TIMETAL 639 (Ti-639), produced by replacing a portion of vanadium in Ti-64 with molybdenum. The low diffusivity and β-stabilizing effects of molybdenum help retain bimodal characteristics within solution heat-treated Ti-639 microstructures. EBSD and TEM were used to examine β-phase evolution after thermal processing and recrystallization of new globular α grains within pre-existing colonies in a depleted bimodal microstructure. These depleted bimodal colonies in solution heat-treated Ti-639 also led to lower misorientation spreads and dislocation densities within neighboring primary α grains. Quasi-static compression along the plate normal direction demonstrated the ability of the depleted bimodal microstructure to simultaneously enhance strength and ductility in Ti-639 (~90 MPa stronger, ~6% higher failure strain) versus identically processed Ti-64. Only one solution heat-treatment step (1 h at 900 °C) is needed to achieve these properties in Ti-639, whereas comparable properties in Ti-64 required prolonged aging heat treatment (24 h at 600 °C) after the same solution heat-treatment step, making Ti-639 a viable α + β alloy candidate. [ABSTRACT FROM AUTHOR]

The continuous inflammatory response in diabetic skin wounds leads to excessive production of reactive oxygen species, which cause a vicious circle of long-term inflammation. In the therapeutic research of metal nanoenzymes for healing diabetic ulcers, it still faces the challenges in poor nanoenzymes activity and low-efficient therapeutic efficiency. Herein, ultrasmall oxygen-deficient MoO3−X quantum dots were fabricated and employed as nanoenzymes for healing fiabetic ulcers. After PEGylation, PEGylated MoO3−X quantum dots (MoO3−X/PEG) with oxygen vacancies exhibits excellent photothermal, peroxidase/catalase-like activities. In addition, these MoO3−X/PEG showed superior properties in scavenging H2O2 and effectively inhibiting the scavenging of reactive oxygen species. More importantly, such an oxygen-defected MoO3−X/PEG had obvious antibacterial and skin repairing effects on alleviating hypoxia and excessive oxidative stress even in a mouse model of diabetic ulcers, inhibiting proinflammatory cytokines and significantly accelerating the healing of infected wounds, which shows great application potential for promoting wound healing. This work highlights that the developed oxygen defected molybdenum oxide compounds capable of peroxidase-like and catalase-like activities show great application potential for healing diabetes wound. [ABSTRACT FROM AUTHOR]

Environmental context: Mitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents. Rationale: Bioremediation harnesses microorganisms' diverse metabolic abilities to detoxify and eliminate pollutants, particularly hydrocarbon-based ones such as oil. This natural biodegradation process performed by microorganisms is a cost-effective method for environmental cleanup compared to other remediation technologies. Methodology: In this study, we examined the fate of heavy metals, cobalt and molybdenum, by the analysis of the basic chemical parameters of other sample components, such as n -hexane extractable substances and total petroleum hydrocarbons. The metal content was determined using inductively coupled plasma–optical emission spectrometry (ICP-OES). Exchangeable (loosely bound to the surface of particles and due to its high mobility and availability is crucial for understanding the potential immediate impact of metal contamination) and more stable fractions of the metal and the metal forms were determined using a sequential extraction method. The phase composition of the samples was determined by X-ray diffraction. Results: In our microbiological analysis, we isolated various cultures from a consortium of microorganisms. Basic chemical analysis indicators, such as n -hexane extractable substances, total petroleum hydrocarbons and humic acids, reflected robust microbiological activity. During the study, metals in exchangeable form decreased and those in more stable forms increased. Discussion: The sequential extraction of cobalt and molybdenum revealed shifts in various metal fractions within the bioaugmented substrate post-bioremediation, differing from the initial substrate. These alterations in metal fractions are likely attributable to microbial actions, leading to the formation of more stable metal fractions throughout the bioremediation process. Environmental context. Mitigating the environmental fallout of industrial accidents is crucial. In a recent study, researchers conducted tests on model substrates to explore the effectiveness of bioremediation in treating complex refinery contaminants resulting from both accidental and deliberate facility damage. The research reveals that bioremediation can be a promising, eco-friendly solution for cleaning up such pollutants, aligning with broader efforts to combat environmental harm resulting from industrial incidents. [ABSTRACT FROM AUTHOR]

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In this study, we elucidate the synthesis and characterization of molybdenum (Mo) doped zinc oxide (ZnO) nanoflowers (Mo-ZnO@NF) fabricated via a hydrothermal approach, showcasing their potential application in hydrogen generation and dye degradation. The successful synthesis of these nanoflowers is achieved through the deliberate incorporation of Mo ions into the ZnO lattice, yielding a distinctive hierarchical flower-like morphology. Comprehensive structural, morphological, and optical analyses are conducted employing a suite of analytical techniques, encompassing XRD, Raman, FESEM, and UVVisible spectroscopy. XRD analysis confirms the retention of the hexagonal wurtzite crystal structure, accompanied by discernible peak shifts indicative of Mo ion integration. FESEM imaging further elucidates the flower-like architecture of Mo-ZnO, underscoring the intricate morphological features. Photocatalytic assessment reveals the remarkable efficacy of Mo-ZnO@NF, as evidenced by an unprecedented hydrogen evolution rate of 2024mmol/h/g and 97% Methylene Blue (MB) dye degradation within a mere 40-minute timeframe. Furthermore, a comparative investigation between pristine ZnO and varying Mo doping concentrations (ranging from 1% to 5%) underscores the optimal doping concentration of 1% Mo in ZnO. This concentration threshold is shown to engender superior photocatalytic performance, potentially attributed to enhanced charge carrier separation and increased surface area conducive to catalytic reactions. Overall, this study not only advances our understanding of Mo-ZnO@NF nanostructures but also elucidates key insights into optimizing their photocatalytic efficacy for diverse environmental remediation applications. [ABSTRACT FROM AUTHOR]

Purpose: To clarify the geographical distribution pattern of asymbiotic nitrogen activity and diazotrophic community in paddy soils, and to understand the primary environmental driving factors driving asymbiotic nitrogen fixation rate (ANFR) and community diversity. Materials and methods: The ANFR and the environmental driving factors of diazotrophic community diversity were investigated in 76 paddy soils across 6 major rice-growing regions in China by 15N2 labeling and nifH gene high-throughput sequencing. Results and discussions: Among all the sample sites, the northeast region had relatively higher ANFR (p < 0.05) compared to other regions. There was no significant correlation between soil ANFR and nifH abundance. The ANFR was significantly affected by Mo, total N and total P, while C:N ratio, exchangeable Ca and pH had a significant influence on nifH abundance. Proteobacteria, Thermodesulfobacteriota and Cyanobacteria dominated within the diazotrophic community across the paddy soils. Furthermore, 50.7% of the variance in community compositions could be attributed to different environmental variables. These multifactorial drivers, including Ca, C:N ratio, Mg, Na, Mn, N:P ratio, Mo and pH, significantly influence formation of specific diazotrophic microbial groups. Conclusions: (1) No significant correlation between the rate of asymbiotic nitrogen fixation in paddy soil and the abundance of the nifH gene. (2) The ANFR was significantly positively correlated with the molybdenum, phosphorus, potassium, nitrogen and organic carbon contents. (3) The abundance of the nifH gene was primarily correlated with Ca content and the soil C:N ratio. (4) Distinct diazotrophic communities are influenced by different environmental drivers. (5) Alphaproteobacteria and Spirochaetota are more abundant in soils with high elevated nitrogen and molybdenum content, indicating their significant contributions to nitrogen fixation in paddy soil. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) is a highly endothermic process, with its development hindered by the harsh thermocatalytic conditions required. We propose an innovative DRM approach utilizing a 16 W pulsed laser in combination with a cost-effective Mo2C catalyst, enabling DRM under milder conditions. The pulsed laser serves a dual function by inducing localized high temperatures and generating *CH plasma on the Mo2C surface. This activates CH4 and CO2, significantly accelerating the DRM reaction. Notably, the laser directly generates *CH plasma from CH4 through thermionic emission and cascade ionization, bypassing the traditional step-by-step dehydrogenation process and eliminating the rate-limiting step of methane cracking. This method maintains a carbon-oxygen balanced environment, thus preventing the deactivation of the Mo2C catalyst due to CO2 oxidation. The laser-catalytic DRM achieves high yields of H2 (14300.8 mmol h−1 g−1) and CO (14949.9 mmol h−1 g−1) with satisfactory energy efficiency (0.98 mmol kJ−1), providing a promising alternative for high-energy-consuming catalytic systems. Dry reforming of methane (DRM) is a highly endothermic process, often limited by the severe thermocatalytic conditions it demands. Here the authors introduce a novel DRM method that employs a 16 W pulsed laser along with a cost-effective Mo2C catalyst, allowing DRM to proceed under milder conditions. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of two bis(dithiolene) proligands involving heteroatomic linkers such as 1,4-dithiine and dihydro-1,4-disiline between the two protected dithiolene moieties are described. Two bimetallic complexes involving these heteroatomic bridges between two redox active bis(cyclopentadienyl)molybdenum dithiolene moieties have been synthesized and characterized by electrochemistry, spectroelectrochemistry, and their properties rationalized with (TD-)DFT. Cyclic voltammetry experiments show sequential oxidation of the two redox centers with ΔE values between successive one-electron transfers varying according to the nature of the bridge. Depending on the nature of the heteroatomic bridge, the bis-oxidized complexes exhibit either a diradical character with both radicals essentially localized on the metallacycles, or a closed-shell dicationic state. [ABSTRACT FROM AUTHOR]

Herein, we demonstrate a sodium/molybdenum (Na/Mo) co-doped ferroelectric PbTiO3 for efficient photocatalysis under visible light. Doped with a high concentration of Mo6+, quasi-continuous new energy levels are successfully introduced below the conduction band minimum of PbTiO3, giving rise to a band-to-band redshift of the absorption edge. The valence state difference of Mo6+ and Ti4+ in the doped PbTiO3 is compensated by the Na dopant, thus effectively suppressing the formation of the recombination centres caused by Mo4+. Combined with the intrinsic built-in electric field in PbTiO3, this Na/Mo co-doping strategy enables PbTiO3 to exhibit superior water oxidation activity under visible light with threshold wavelength up to 550 nm, which also promotes overall water splitting under visible light in a Z-scheme photocatalytic system. This strategy provides a generally applicable solution to extend the visible light absorption spectrum and engineer electronic structures of ferroelectric materials for photocatalysis and other energy conversion applications. [ABSTRACT FROM AUTHOR]

Molybdenum carbide materials have demonstrated remarkable potential in catalyzing the hydrogen evolution reaction (HER). However, further modulation of their performance through simultaneously engineering the size and surface crystal facets remains challenging. Herein, we report the successful fabrication of N-doped carbon-supported monodisperse Mo 2 C nanoparticles with a size of ∼2.06 nm, exhibiting co-exposed (101)/(102) facets-heterojunction, derived from annealing glycine and ammonium molybdate tetrahydrate. The optimized Mo 2 C/NC-Amt catalyst exhibits a low overpotentials of 128 mV to achieve the current density of 10 mA cm−2 and a small Tafel slope of 72 mV dec−1 under alkaline solution. By changing the molybdate precursor, the phase and crystal facet composition of molybdenum carbide can be effectively tuned, which provides a good platform for studying their structure-activity in HER. The theoretical calculations reveal the synergistic effect of (101)/(102) facets-heterojunction accelerates electron transfer and regulates the d band center of Mo 2 C, reducing the reaction barriers of intermediates in the HER process, thus significantly boosting reaction activity. This work proposes a novel insight into the rational fabrication of efficient HER catalysts through facet engineering toward heterojunction construction under the 2.5 nm region. [Display omitted] • Monodisperse Mo 2 C nanoparticles (∼2.06 nm) on N-doped carbon are synthesized. • The formed surface heterojunction involves (101) and (102) facets of Mo 2 C. • DFT calculations reveal the synergistic mechanisms of the facet heterojunctions. • The optimized catalyst presents distinguished HER performance in 1 M KOH. [ABSTRACT FROM AUTHOR]

Aluminum technical alloys are well known for their outstanding mechanical properties, especially after heat treatment. However, quenching and aging, which improve the mechanical properties, by the formation of Cu-rich zones and phases that are coherent with the matrix and block the dislocation motion, cause uneven distribution of the elements in the alloy and consequently make it prone to corrosion. One method providing satisfactory corrosion protection of aluminum alloys is anodizing. On an industrial scale, it is usually carried out in electrolytes containing chromates that were found to be cancerogenic and toxic. Therefore, much effort has been undertaken to find substitutions. Currently, there are many Cr(VI)-free substitutes like tartaric–sulfuric acid anodizing or citric–sulfuric acid anodizing. Despite using such approaches even on the industrial scale, Cr(VI)-based anodizing still seems to be superior; therefore, there is an urge to find more complex but more effective approaches in anodizing. The incorporation of anions into anodic alumina from the electrolytes is a commonly known effect. Researchers used this phenomenon to entrap various other anions and organic compounds into anodic alumina to change their properties. In this review paper, the impact of the incorporation of various corrosion inhibitors into anodic alumina on the corrosion performance of the alloys is discussed. It is shown that Mo compounds are promising, especially when combined with organic acids. [ABSTRACT FROM AUTHOR]

Wire electrical discharge machining (WEDM) is an unconventional machining technology which is widely used in all industries. Due to the increased energy demand of WEDM, there is an effort to reduce machining times and thus maximise the material removal rate (MRR). Thus, this study aimed to perform the design of experiment to study the effect of WEDM machining parameters on the resulting MRR, topography, morphology, and subsurface condition of the produced samples. The materials investigated included titanium alloy Ti-6Al-4 V, aluminium alloy 7475-T7351, nickel alloy Nimonic C 263, wear-resistant Hadfield steel, copper alloy Ampcoloy 35, pure molybdenum 99.99, and high-entropy alloy FeCoCrMnNi. The highest MRR values were achieved for 7475-T7351. Nimonic, Hadfield steel, Ampcoloy, and molybdenum materials reached similar MRR values and the lowest MRR values were studied for Ti-6Al-4 V and FeCoCrMnNi materials. Cracks were visible on all samples of Ti-6Al-4 V, molybdenum and aluminium alloy 7475-T7351, while burnt cavities were found in Hadfield steel. [ABSTRACT FROM AUTHOR]

Nitrogenase plays a key role in the global nitrogen cycle; yet, the evolutionary history of nitrogenase and, particularly, the sequence of appearance between the homologous, yet distinct NifDK (the catalytic component) and NifEN (the cofactor maturase) of the extant molybdenum nitrogenase, remains elusive. Here, we report the ability of NifEN to reduce N2 at its surface-exposed L-cluster ([Fe8S9C]), a structural/functional homolog of the M-cluster (or cofactor; [(R-homocitrate) MoFe7S9C]) of NifDK. Furthermore, we demonstrate the ability of the L-cluster-bound NifDK to mimic its NifEN counterpart and enable N2 reduction. These observations, coupled with phylogenetic, ecological, and mechanistic considerations, lead to the proposal of a NifEN-like, L-cluster-carrying protein as an ancient nitrogenase, the exploration of which could shed crucial light on the evolutionary origin of nitrogenase and related enzymes. [ABSTRACT FROM AUTHOR]

Molybdenum tailings (MTs) and kaolinite were used as the main materials in the fabrication ceramic foams (CFs) via the high-temperature sintering method, with the addition of SiC as a foaming agent. The effects of MT content on the basic physical properties, pore structure, and chemical characterization were investigated. Results showed that MT enhanced the foaming capability. When the MT content was 60% and the sintering temperature was 1170 °C, the optimum CFs obtained demonstrated bulk density, porosity, water absorption, and compressive strength of 0.55 g/cm3, 77.3%, 6.94%, and 6.74 MPa, respectively, and the pore structure was relatively homogeneous with an average pore diameter of 0.67 mm. The results revealed that SiO 2 –-Al 2 O 3 –-MgO–-CaO system CFs can be prepared from Ca–Mg-rich MT, which provided a feasible strategy for value-added utilization of Ca–Mg-rich MT. [ABSTRACT FROM AUTHOR]

The material design concept of high-entropy alloy (HEA) is proposed for Tribaloy alloys. In this research, three HEAs are created by mixing Co-based T-800 and Ni-based T-700 Tribaloy alloys in different ratios and fabricated via spark plasma sintering (SPS) process. The phase transformation behavior of the mixed powders of T-800 and T-700 is investigated with differential scanning calorimetry (DSC) analysis. The microstructures of the SPS specimens and solidified DSC samples of the created HEAs are studied using SEM and XRD, showing that they consist of fcc Co, Mo, and Ni solid solution with minor hcp Co solid solution, various Laves phase, mainly Co3Mo2Si, CoMoSi, Ni3Mo2Si, Mo2Si, and CrSi2, and complex intermetallic compounds. The hardness and dry-sliding wear resistance of the created SPS HEAs are evaluated and compared with the initial alloys (T-800 and T-700). It is shown that the hardness and wear resistance of T-800 are much higher than that of T-700, which is attributed to the excellent properties of element Co; the created HEAs exhibit better hardness and wear performance than T-700 but worse than T-800. The HEA having an equal mixture ratio of T-800 and T-700, with the largest configurational entropy of 1.58R, performs the best in wear resistance among the HEAs. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic inflammatory disease that affects more than 60 million people worldwide. Its pathogenesis involves the interplay of immune and oxidative stress mechanisms with feedback loops reinforced between them. Alleviating the state of oxidative stress will break this loop and relieve chronic inflammation, making it a potential therapeutic target. We synthesized a kind of molybdenum nanoparticle which reduced reactive oxygen species (ROS) in HaCaT cells in a psoriasis-mimicking environment and decreased the production of inflammatory mediators such as IL-17A, IL-23, IFN-γ, and TNF-α, which play a crucial role in the onset of psoriasis. In a mouse model of psoriasis, molybdenum particles in its specific nanoscale alleviated erythema, scaling, and thickening of lesions and reduced the infiltration of inflammatory cells and the expression of relevant inflammatory mediators in skin lesions. The levels of phosphorylated p65 were significantly reduced in both in vitro and in vivo models after the application of molybdenum nanoparticles, suggesting that this material, especially due to its nanoscale, may reduce the production of inflammatory mediators and proliferation of keratinocytes through a ROS/NF-κB axis, thereby improving psoriasis symptoms. Our study suggests that molybdenum nanoparticles are a promising treatment strategy for patients with psoriasis. [ABSTRACT FROM AUTHOR]

Two molybdenum complexes, MoHL1 and MoHL2, are prepared from the corresponding tetradentate salen type (ONNO) ligands, HL1 and HL2, obtained from 3, 5‐dichloro salicylaldehyde, and substituted o‐phenylenediamines. The complexes are characterized by 1H NMR, FTIR, HRMS, and UV‐visible spectral techniques. The DFT studies provide insight into their structural parameters. The band gap energy and molecular orbital energies influence the charge transfer interactions within the molecule. Further, the complexes are assessed for their antioxidant efficacy, α–amylase inhibitory potential, binding propensity with deoxyribonucleic acid, and cytotoxicity studies against breast cancer cell line, MCF7. The DPPH assay demonstrates high radical scavenging ability, as evidenced by the IC50 value of 133.85±1.18 μg/mL, higher than ascorbic acid. From the results of α–amylase inhibitory assay, MoHL1 shows good inhibitory action with the IC50 value of 32.72±2.49 μg/mL higher than that of the standard acarbose. The absorption titration method, to track the binding interactions of the metal complexes with DNA, shows a marked hyperchromic effect indicating preferential binding of the complexes to the grooves of DNA helical structure. MoHL2 exerts higher cytotoxicity against cancer cell lines than MoHL1. Thus, the complexes have the potential to be developed as antidiabetic and anticancer agents. [ABSTRACT FROM AUTHOR]

In this study, BiMeVOx compounds (where Me: Co, Mo, Ce, Zr) were synthesized and characterized as potential photoelectrochemical materials for solar water splitting, the hydrogen evolution reaction (HER), and oxygen evolution reaction (OER). The analysis confirmed the successful formation of phase BiMeVOx compounds with the desired crystal structure. Among the tested materials, BiCoVOx(800) showed the highest photocurrent density (674 μA cm−2) and HER/OER activity (Tafel slope: HER = 100 mV dec−1 and OER = 75 mV dec−1), followed by BiMoVOx(800), BiCeVOx(800), and BiZrVOx(800). The superior photoelectrochemical performance of BiCoVOx(800) can be attributed to its unique electronic structure and optimized band alignment, which promote efficient charge separation and facilitate the water splitting and hydrogen evolution processes. The findings of this study highlight the promising potential of the synthesized BiMeVOx materials, particularly BiCoVOx, as efficient photoelectrochemical catalysts for water splitting. These results contribute to the advancement of renewable energy technologies and provide valuable insights for the design and development of novel photoactive materials. [Display omitted] • BiMeVOx (Me: Co, Ce, Mo, Zr) catalysts were synthesized for water electrolysis to produce hydrogen energy. • BiCoVOx(800) as a Bifunctional Catalyst for HER and OER. • The BiCoVOx photoanode shows a photocurrent density of Δj = 674 μA cm−2. • Multifunctional BiCoVOx Enhances Water Splitting. [ABSTRACT FROM AUTHOR]

Octanuclear polyoxomolybdenum-based porous materials, Na8[Mo8O8(µ2-O)8(µ2-OH)8(3-apz)4]2·26H2O (1, 3-Hapz = 3-aminopyrazole), K8[Mo8O8(µ2-O)8(µ2-OH)8(3-apz)4]2·7H2O (2) and (NH4)4[Mo8O8(µ2- O)8(µ2-OH)4(3-apz)8]·20.5H2O (3), have been successfully synthesized by a hydrothermal method and fully characterized. X-ray structural analyses show that microporous materials 1-3 contain round pores formed by octanuclear molybdenum-oxygen groups connected sequentially with pore sizes of 4.0, 4.0, and 4.8 Å, respectively. Both 1 and 2 are composed of two {Mo8} rings, which are connected by strong intramolecular hydrogen bonds between bridging hydroxy groups and oxygen atoms to form dimeric structures. The central pores in 1 and 2 are occupied by Na+ and K+, respectively, while they are empty in 3. This reflects the structural expansion and contraction effects induced by different cations. Through intermolecular stacking, 1-3 also exhibit channels with sizes of 14.0 × 6.4, 4.6 × 2.6, and 5.4 × 5.4 Å, respectively, which were used for the studies of gas adsorption. The results show that 1-3 can selectively adsorb CO2 and O2, including the empty hole in 3, while they show little or no affinity for gases H2, N2, and CH4. Moreover, an additional polyoxomolybdenum-based species (Mo8O26)n·4n(3-H2apz) (4) has been obtained with protonated 3-aminopyrazole in the absence of a reducing agent, which can serve as an intermediate for the polyoxomolybdenum-based porous products. [ABSTRACT FROM AUTHOR]

In this work, Ru nanoparticles doped with Mo on reduced graphene oxide (RuMo/rGO) are prepared through synchronous reduction of RuCl3, MoCl5, and graphene oxide. The compositions, morphologies, and structures of the as-prepared RuMo/rGO composites are fully characterized. Their catalytic properties in oxidative cleavage of β-O-4 linkages in lignin model compounds and lignin are explored. It is illustrated that with O2 as the oxidant RuMo/rGO shows overall better catalytic performance in the oxidative cleavage of β-O-4 linkages than the catalysts, such as Ru/rGO and RuCo/rGO, reported in our previous work. The catalytic mechanism is elaborated through experiments and density functional theory (DFT) calculation. Pronouncedly, we show that the as-doped Mo can effectively boost the molecular oxygen activation process and the adsorption of β-O-4 model compounds on the Ru nanoparticle surface on rGO, and thus enhance the catalytic activity. It is demonstrated meanwhile that RuMo/rGO can catalyze the depolymerization of organosolv birch lignin yielding 17.1% aromatic compounds under relatively mild conditions (100 °C, 0.3 MPa O2, 12 h, pH = 12). [ABSTRACT FROM AUTHOR]

Metal borides have received a lot of attention recently as a potentially useful material for a wide range of applications. In particular, molybdenum‐based borides and MBenes are of great significance, due to their remarkable properties like good electronic conductivity, considerable stability, high surface area, and environmental harmlessness. Therefore, in this article, the progress made in molybdenum‐based borides and MBenes in recent years is reviewed. The first step in understanding these materials is to begin with an overview of their structural and electronic properties. Then synthetic technologies for the production of molybdenum borides, such as high‐temperature/pressure methods, physical vapor deposition (PVD), chemical vapor deposition (CVD), element reaction route, molten salt‐assisted, and selective etching methods are surveyed. Then, the critical performance of these materials in numerous applications like energy storage, catalysis, biosensors, biomedical devices, surface‐enhanced Raman spectroscopy (SERS), and tribology and lubrication are summarized. The review concludes with an analysis of the current progress of these materials and provides perspectives for future research. Overall, this review will offer an insightful reference for the understanding molybdenum‐based borides and their development in the future. [ABSTRACT FROM AUTHOR]

The mechanism of the water gas shift reaction (WGSR) catalyzed by Mo(CO) 6 in both gaseous and aqueous phases were analyzed using the density functional theory (DFT) method. This study indicates that aqueous phase slightly increased every energy barrier for each step along the reaction path. The turnover frequency (TOF) of the reaction was determined using the energy span model (ESM). The TOF value in the aqueous phase (2.48 × 10−16 s−1) is slightly lower than in the gas phase (6.08 × 10−16 s−1). Actually, the advantages of aqueous phase may be attributed to high solubility and concentration of H 2 O, CO, OH−. The study of temperature (300–900 K) on energy profile shows that the reaction rate of WGSR can be increased with the increase of temperature. This research filled the gap in understanding the mechanism for the WGSR in aqueous phase, provides a reasonable theoretical foundation for molybdenum-based catalysts development. • Mechanisms of gaseous phase and aqueous phase carbonyl complexes Mo(CO) 6 catalyzed WGSR are reported. • The energetic span model is applied to reveal the kinetic behavior of the catalytic cycles. • The increase in temperature is beneficial for accelerating the reaction rate. [ABSTRACT FROM AUTHOR]

Porphyry-type molybdenum deposits, many of which are in China, supply most of the World's molybdenum. Of particular importance are the molybdenum deposits located in the Qinling-Dabie region that are responsible for more than half of China's molybdenum production. A feature that distinguishes this suite of deposits from the better-known Climax and Endako sub-types of porphyry molybdenum deposits is their formation from CO2-rich magmatic-hydrothermal fluids. The role of CO2, if any, in the transport of molybdenum by these fluids, however, is poorly understood. We conducted experiments on the partitioning of molybdenum between H2O-CO2, H2O-NaCl, and H2O-NaCl-CO2 fluids and a felsic melt at 850 °C and 100 and 200 MPa. Here we show that the exsolution of separate (immiscible) brine and vapor leads to the very high brine DMo values needed for efficient extraction of Mo from the magmas forming Dabie-type porphyry molybdenum deposits. Direct exsolution of immiscible CO2 vapour and brine from magma greatly enriches the brine in molybdenum, a likely factor in the genesis of the Dabie-type porphyry deposits that supply much of the World's molybdenum [ABSTRACT FROM AUTHOR]

Cobalt molybdenum nitrides can be obtained from the oxidic precursor by reaction with gaseous ammonia. Despite the large number of works regarding the catalytical properties of these compounds, there are relatively few reports about the initial transformation from oxide to nitride. In this work, the influence of the precursor structure on the active phase formation and catalytic properties of cobalt molybdenum nitrides is examined. Oxidic precursors were obtained by precipitation at different pH values controlled by the addition of aqueous ammonia. The parameters of the precipitation process affected the composition and properties of the materials. The ammonolysis of NH4Co2OH(MoO4)2 ⋅ H2O was investigated in situ with the use of X‐ray powder diffraction and thermogravimetry. The ammonia synthesis activity of the obtained catalysts was compared to the reference iron catalyst. The formation of the Co3Mo intermetallic phase was suggested as the factor governing high activity. [ABSTRACT FROM AUTHOR]

This study utilizes the monochromatic X-ray radiation device established by the National Institute of Metrology, China, to conduct a systematic experimental investigation of the mass attenuation coefficients of niobium, molybdenum, tantalum, and tungsten metals near their K absorption edges. The device's ability to generate continuously tunable monochromatic X-rays and accurately measure photon counts provides an ideal condition for precise mass attenuation coefficient measurements. This study employs a minimum energy step of 0.1 keV to systematically obtain the jump ratio rK and jump factor JK near the K-absorption edges of the four materials. The experimental measurements are compared with theoretical values from NIST-XCOM, NIST-FFAST, and Phy-x databases, demonstrating a consistent trend between the experimental and theoretical results, with relative deviations within acceptable limits, thereby validating the reliability of the theoretical models. An uncertainty analysis reveals a combined relative uncertainty of less than 2.7 %, indicating that the experimental results and theoretical values are in good agreement, with deviations and uncertainties within acceptable ranges. This research provides important experimental data and theoretical references for the application of monochromatic X-ray radiation devices in the field of mass attenuation coefficient measurements. [ABSTRACT FROM AUTHOR]

The results of studies on the preparation of highly dispersed bimetallic materials based on platinum with chromium, molybdenum, and tungsten under autoclave conditions at 190°C are summarized in this report. The thermodynamic and chemical features of the interactions between [Pt(NH3)4]Cl2 and (NH4)2CrO4, (NH4)2MoO4 and (NH4)2WO4 are considered. Solid products (powders) are represented by two phases—Pt and disordered solid solutions based on platinum. The morphology of powders has been studied—spherical particles with a diameter of 300–700 nm form agglomerates up to 2 µm. A route for the reduction of platinum (II) and oxometalate anions to the corresponding metals with intrasphere ammonia is proposed. The results of this work can form the basis for the synthesis of catalysts that are widely used in a number of industrially important reactions. [ABSTRACT FROM AUTHOR]

To address the disadvantage of poor degradation effect of Fe2+/peroxydisulfate (PDS) system, a co-catalyst was introduced in this study to construct a molybdenum (Mo)/Fe2+/PDS system for the degradation of Acid Orange 7 (AO7), and the degradation rate could reach 95.67%. The effects of different parameters (initial pH, Fe2+ concentration, etc.) on the degradation effect of AO7 in this system were investigated, and the optimal degradation conditions were obtained by combining cost analysis. Cycling experiments showed that Mo had good stability. The co-catalytic mechanism of Mo powder was determined using X-Ray Diffraction, Scanning Electron Microscope, and X-ray Photoelectron Spectroscopy. The effects of different inorganic anions on AO7 were discussed: Cl− and NO3− had little effect on degradation, while SO42− and HCO3− both inhibited the removal of AO7 from the system to different degrees, with HCO3− showing a greater inhibition than SO42−. The main active radicals were identified as sulfate radical (SO4·−) and hydroxyl radical (·OH). In addition, intermediates were identified, and the attack sites were determined by combining the highest occupied molecular orbital/lowest unoccupied molecular orbital energy levels and the Fukui index to hypothesize the degradation pathways. Toxicity indicators such as the mutagenicity of AO7 and intermediates were evaluated, and the overall trend of toxicity was decreasing. This study is expected to provide an efficient treatment process for dye wastewater. [ABSTRACT FROM AUTHOR]

The structural and electronic properties of pure graphene, graphene with a vacancy, graphene with two vacancies and molybdenum‐doped graphene were investigated. In addition, the adsorption of Mo atoms on graphene (G), reduced graphene (rG) and reduced graphene oxide (rGO) was examined. The possible energies of different active adsorption sites of nanostructured Mo‐decorated G, rG and rGO have been calculated using density functional theory (DFT). Mo atoms are predicted to create bonds with six C atoms in G, three C atoms in rG, and both C and O atoms in rGO sheets after geometry optimizations. The study focused on changing the electronic structure of G, including opening the zero band gap and controlling the band structure, which was done by creating defects and adding impurities. The present study revealed a significant correlation between the adsorption of the Mo atom and the characteristics exhibited by frontier orbitals. The results indicated that the adsorption characteristics of Mo atoms in pure G, rG and rGO are different, despite chemisorption being the common mechanism. Specifically, Mo‐decorated rG exhibited higher adsorption energy, while Mo‐decorated G demonstrated a lower adsorption energy. According to these findings, it is reasonable to anticipate that Mo‐decorated rG could be applied as a novel adsorbent for the removal of pollutants. [ABSTRACT FROM AUTHOR]

By means of density functional theory, the energy‐loss near‐edge structure (ELNES) of carbon K‐edge of Mo2TiAlC2 and corresponding MoTiC2 Mxene at orientational‐independent condition is dealt with. Compared to the MAX (M is transition metal, A is an elment from group 13–16, X is C or N) phase, the energy separations increase between the main spectral features at the C K edge of Mo2TiC2 MXene owing to the structural change and decreased bond length. The dispersions of the C K edge in both systems are similar to p‐symmetry densities of states. It is indicated that the source of the first fine structure at the C 1s edge in both phases mainly comes from the electron transfer to px + py‐like character. The other fine structures result from the transition to hybridization of pz and px + py states with the prominent contribution of px + py‐like character. Moreover, the comparison of C K‐edge ELNES spectra in three Mo‐based compounds reveals that, ongoing from Mo2TiAlC2 to Mo2TiC2 and then to Mo2C, the energy position of the fine structures is shifted to higher energies (blueshifted), due to the quantum confinement effects and the change of the chemical environment around the excited carbon. [ABSTRACT FROM AUTHOR]

Molybdenum cofactor deficiency classically presents in neonates with intractable seizures; however, milder cases generally present before age 2 years with developmental delays and may go undiagnosed. Early diagnosis, and safe, US Food and Drug Administration-approved substrate replacement are critical to preserve neurologic function. This article discusses 2 children who presented with late-onset molybdenum cofactor deficiency type A. [ABSTRACT FROM AUTHOR]

Y2O3 dispersion-strengthened Molybdenum (Mo) composites were prepared by the mechanical alloying of Mo and Y powders then consolidation by spark plasma sintering. The effects of Chromium (Cr) addition (0 wt. %, 5 wt. %, 10 wt. % and 15 wt. %, respectively) on the mechanical performance and high-temperature oxidation resistance of Mo-Y2O3 were investigated. The introduction of Cr had a significant influence on the mechanical property and oxidation resistance of the Mo-Y2O3 composite. The highest bending strength reached 932 MPa when the addition of Cr content was 5 wt. % (Mo–5Cr–1Y sample). This improvement is likely attributable to the dual mechanism of grain refinement and solid solution strengthening. Moreover, the Mo–5Cr–1Y sample showed the thinnest oxide layer thickness after high-temperature oxidation tests, and exhibited the best oxidation resistance performance compared with the other samples. First principle calculation reveals that Cr could improve the Mo–MoO3 interface bonding to prevent rapid spalling of the oxide layer. Meanwhile, Cr also facilitates the formation of the dense Cr2(MoO4)3 layer on the surface, which can inhibit further oxidation. [ABSTRACT FROM AUTHOR]

The Gaoaobei tungsten-molybdenum deposit is a newly discovered large-scale quartz-vein-type deposit in the Nanling metallogenic belt in South China. The ore bodies are hosted in the Indosinian granites and the Cambrian Xiangnan Group slates and are controlled by NWW-oriented faults, which are obviously different from the "five-story building" model in southern Jiangxi Province. The magmatic rocks in the study area are dominated by medium- to coarse-grained biotite monzogranite, with a few NW-oriented fine-grained granite dykes. The medium- to coarse-grained biotite monzogranite and fine-grained granite dykes have zircon U-Pb ages of 229.4 ± 1. 9 Ma (MSWD = 1.5) and 164.9 ± 3.3 Ma (MSWD = 0.75), respectively, corresponding to the Indosinian and Yanshanian magmatism. The monzogranites have higher contents of FeO, CaO, K2O, P2O5, and TiO2, while the granite dykes have slightly higher contents of SiO2, Al2O3, MnO, and Na2O. Their A/CNK values are 1.11–1.75 and 1.19–2.25, and the contents of CIPW normative corundum are 1.71%–6.66% and 2.41%–9.50%, suggesting both the monzogranites and granite dykes are S-type granite. The total amount of rare earth elements in the monzogranites (from 84.7 ppm to 129 ppm) is slightly lower than that in the granite dykes (from 128 ppm to 133 ppm). The Eu/Eu* values range from 0.12 to 0.30 in monzogranites and from 0.001 1 to 0.001 3 in granite dykes, indicating the fine-grained granites underwent more intense fractional crystallization. The monzogranite and granite dykes have high 87Sr/86Sri values of 0.716 9–0.719 3 and 0.728 25–0.728 80, low εNd(t) values ranging from −10.2 to −9.6 and from −11.5 to −11.4, and TDM2 ages of 1 835–1 785 and 1 957–1 946 Ma, respectively. These isotope data indicate their origin from the remelting of the Paleoproterozoic crustal materials. Combined with regional geology, it is concluded that the medium- to coarse-grained biotite monzogranite was formed in a post-collisional extensional environment. In addition, 40Ar-39Ar dating of the greisen type tungsten-molybdenum ore gave consistent plateau age of 164.0 ± 1.2 Ma, isochronal age of 162.0 ± 2.4 Ma and anti-isochronal age of 161.4 ± 1.8 Ma. Combined with the published molybdenite Re-Os age, the Gaoaobei tungsten-molybdenum deposit was formed at ∼164 Ma, which is inferred to be genetically related to the contemporaneous finegrained granite dykes (165 Ma). The deposit was likely formed during the large-scale magmatism and mineralization event in the early Yanshanian of the Nanling Range in an intra-continental extensional environment caused by the subduction of the paleo-Pacific plate. The late and small granite dykes within the large granite plutons thus require further attention during mineral prospecting in the regions. [ABSTRACT FROM AUTHOR]

Periplasmic nitrate reductase NapA from Campylobacter jejuni (C. jejuni) contains a molybdenum cofactor (Moco) and a 4Fe–4S cluster and catalyzes the reduction of nitrate to nitrite. The reducing equivalent required for the catalysis is transferred from NapC → NapB → NapA. The electron transfer from NapB to NapA occurs through the 4Fe–4S cluster in NapA. C. jejuni NapA has a conserved lysine (K79) between the Mo-cofactor and the 4Fe–4S cluster. K79 forms H-bonding interactions with the 4Fe–4S cluster and connects the latter with the Moco via an H-bonding network. Thus, it is conceivable that K79 could play an important role in the intramolecular electron transfer and the catalytic activity of NapA. In the present study, we show that the mutation of K79 to Ala leads to an almost complete loss of activity, suggesting its role in catalytic activity. The inhibition of C. jejuni NapA by cyanide, thiocyanate, and azide has also been investigated. The inhibition studies indicate that cyanide inhibits NapA in a non-competitive manner, while thiocyanate and azide inhibit NapA in an uncompetitive manner. Neither inhibition mechanism involves direct binding of the inhibitor to the Mo-center. These results have been discussed in the context of the loss of catalytic activity of NapA K79A variant and a possible anion binding site in NapA has been proposed. [ABSTRACT FROM AUTHOR]

A nanocomposite of multi-walled carbon nanotubes (MWCNTs) decorated with molybdenum dioxide (MoO2) nanoparticles is fabricated through the reduction of phosphomolybdic acid hydrate on functionalized MWCNTs in a hydrogen–argon (10%) atmosphere in a tube furnace. The MoO2/MWCNTs composite is proposed as an anodic modification material for microbial fuel cells (MFCs). MWCNTs have outstanding physical and chemical peculiarities, with functionalized MWCNTs having substantially large electroactive areas. In addition, combined with the exceptional properties of MoO2 nanoparticles, the synergistic advantages of functionalized MWCNTs and MoO2 nanoparticles give a MoO2/MWCNTs anode a large electroactive area, excellent electronic conductivity, enhanced extracellular electron transfer capacity, and improved nutrient transfer capability. Finally, the power harvesting of an MFC with the MoO2/MWCNTs anode is improved, with the MFC showing long-term repeatability of voltage and current density outputs. This exploratory research advances the fundamental application of anodic modification to MFCs, simultaneously providing valuable guidance for the use of carbon-based transition metal oxide nanomaterials in high-performance MFCs. [ABSTRACT FROM AUTHOR]

Molybdenum tailings are accumulated in large quantities, occupying the land and polluting the environment. Therefore, the resource utilization of molybdenum tailings is imperative. In this paper, the influence of molybdenum tailings powder (MTs) as admixture on hydration characteristics, including hydration heat, hydration products, phase composition, and mechanical properties evolution of cement paste were investigated. Results showed that the early hydration of cement paste can be promoted when the content of MTs is not more than 15%. The compressive strength of cement paste with 15% MTs at 3, 28, and 120 days was 89.37%, 96.14%, and 91.68% of that of the portland cement (PC) group, respectively. When the content of MTs does not exceed 15%, the second exothermic peak of hydration heat of cement paste appears ahead of time and the peak value increases. With the increase of MTs content, the cumulative heat release of 72 h gradually decreased. The addition of MTs does not produce new hydration products, but introduces the mineral phase of MTs itself, and leads to the early transformation of ettringite (AFt) into monosulfoaluminate (AFm) in paste. There is still a close linear relationship between the compressive strength and cumulative heat release and chemically bound water content after addition of MTs into cement paste. It was also discovered that the pozzolanic activity of MTs in cement paste mainly occurred from 3 to 28 days. After 28 days, the particle-filling effect of MTs was dominant mainly. The research results are expected to provide basic research for the resource utilization of MTs. [ABSTRACT FROM AUTHOR]

The current study was conducted during 2022 and 2023 seasons on plum (Prunus salicina Lindl.) cv. Kelsy was planted in sandy soil under a drip irrigation system in a private Farm located at Salah Al-Abd Village, Bostan Region, Nubaria, Behaira Governorate, Egypt to study the effect of foliar application of molybdenum 0.5 g/L, boron at 0.5 g/L, seaweed extract at 2000 ppm, moringa leaf extract at 4000 ppm, molybdenum 0.5g/L + boron 0.5g/L, molybdenum 0.5g/L + seaweed extract 2000ppm, molybedem0.5g/L + moringa extract 4000ppm, boron 0.5g/L + seaweed extract 2000ppm, boron 0.5 g/L + moringa extract 4000 ppm, seaweed extract 2000 ppm + moringa extract 4000 ppm and molybdenum 0.5g/L + boron 0.5g/L + moringa extract4000ppm + seaweed extract 2000 ppm as compared to the control treatments on vegetative growth and yield characteristics. The trees were planted at 3 x 3.5 m in sandy soil under a drip irrigation system. Sixty uniform trees of the same age, growth and size were randomly chosen. The foliar application of the twelve treatments was arranged in a randomized complete block design (RCBD) in five replicates during the two seasons. The trees were sprayed three times; before flowering, after fruit set and after one month after the second spraying. The obtained results showed that the application of the seaweed extract, moringa extract, boron and molybdenum individually or in combination effectively increased the vegetative growth attributes and fruit yield. The best results were obtained by the application of 0.5 g/L boron + 0.5 g/L molybdenum + seaweed extract + moringa extract in both seasons. [ABSTRACT FROM AUTHOR]

Molybdenum‐based efficient and broadly applicable catalytic system is presented for the dehydrogenative coupling of γ‐/β‐amino alcohols with ketones. In particular, complex Mo(CO)6 in combination with Xantphos and t‐BuOK as base provides direct synthesis of structurally diverse quinoline, pyridine, and pyrrole compounds (total 55 examples) with isolated yields up to 92%. Low catalyst loading, cost‐effective, and high catalytic activities with high tolerance to stand with diverse functional groups are additional features of these molybdenum catalysts exhibiting high efficacy to replace the precious metal catalysts such as ruthenium and iridium. Furthermore, the DFT and experimental studies were explored for the reaction mechanism which can assist in broadening the scope of the molybdenum catalysts for different transformation reactions. [ABSTRACT FROM AUTHOR]

Atomically thin two-dimensional transition metal dichalcogenides (TMDCs) have been regarded as ideal and promising nanomaterials that bring broad application prospects in extensive fields due to their ultrathin layered structure, unique electronic band structure, and multiple spatial phase configurations. TMDCs with different phase structures exhibit great diversities in physical and chemical properties. By regulating the phase structure, their properties would be modified to broaden the application fields. In this mini review, focusing on the most widely concerned molybdenum dichalcogenides (MoX2: X = S, Se, Te), we summarized their phase structures and corresponding electronic properties. Particularly, the mechanisms of phase transformation are explained, and the common methods of phase regulation or phase stabilization strategies are systematically reviewed and discussed. We hope the review could provide guidance for the phase regulation of molybdenum dichalcogenides nanomaterials, and further promote their real industrial applications. [ABSTRACT FROM AUTHOR]