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In this study, the hydrogen reduction mechanism of MoO3 was analyzed in detail using Ti–Mo core–shell powder manufactured through a milling and reduction process. MoO3 and Ti powders were ball-milled to refine the MoO3 powder and coat it onto the Ti powder to fabricated core-shell structure. Subsequently, the milled powder was heat-treated at 600°C in a hydrogen atmosphere to reduce MoO3 to nano-sized Mo. In addition, the reduction behavior of MoO3 was analyzed by varing the reduction times to 1, 10, 30 min and 1, 3, 5 h. Phase analysis was conducted using X-ray diffraction, and oxidation state analysis was conducted using X-ray photoelectron spectroscopy. Morphology analysis was performed using scanning electron microscopy, and elemental analysis was conducted using electron probe micro-analysis. It was confirmed that Mo9O26 and Mo4O11 intermediate phases were formed sequentially as MoO3 was reduced to MoO2, and Mo9O26 had a plate shape with a thickness of sub-70 nm, and Mo4O11 exhibited a thickness of sub-300 nm. Especially, the Mo2O3 intermediate phase, previously studied only theoretically, was experimentally confirmed for the first time in the reduction process from MoO2 to Mo. Furthermore, the analysis of Mo-oxide intermediate phases was explained by the structural characteristics of the core–shell. The shell of Mo oxide was thick and dense, making it difficult for the vapor phase necessary for CVT reduction to penetrate and diffuse into the shell. As a result, the rapid CVT reduction occurred outside the shell, while relatively slower reduction occurred inside the shell where intermediate phases were observed.

Maraging steels are one of the highest strength steels commercially available. The new versions are known as ultra-high strength maraging (UHSM) steels and can offer yield strength values over 3 GPa. The aim of this investigation was evaluating the electrochemical behavior of three non-commercial/laboratory UHSM steels containing 13Ni–15Co and Mo content variations (7.5, 11 and 15 wt%). The UHSM steels were annealed at 1000 °C and studied at different conditions (non-aged and aged at 480 °C for 3 h and 6 h). As reference material, a commercial maraging steel (18Ni–9Co–5Mo) heat treated according to typical recommendations (annealed at 820 °C for 1 h and aged at 480 °C for 4 h) was used. The UHSM presented considerable higher hardness than commercial maraging. Comparing between the UHSM steels, the samples treated for 6 h do not contribute to increase the hardness when compared to those of 3 h. The electrochemical tests in hydrochloric aqueous solution showed that commercial maraging steel and the UHSM containing most Mo (11 wt%) aged by 6 h presented the worst corrosion resistance while the best performance was obtained by the samples with 7.5 and 11 wt% Mo aged for 3 h.

Isotope technology is an ideal tool for tracing the sources of certain pollutants or providing insights into environmental processes. In recent years, the advent of multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has enabled the precise measurement of various metal stable isotopes. Due to the presence of ''fingerprint'' properties in various environmental samples, metal stable isotopes have been applied to distinguish the source of contaminants effectively and further understand the corresponding environmental processes. The environmental fate of metal elements is strongly controlled by adsorption, an essential process for the distribution of elements between the dissolved and particulate phases. The adsorption of metal elements on mineral and organic surfaces significantly affects their biogeochemical cycles in the environment. Therefore, it is crucial to elucidate the fractionation characteristics of stable metal isotopes during the adsorption process. In this review, three typical transitional metal elements were selected, considering Mo as the representative of anionic species and Fe and Zn as the representative of cationic species. For Mo, the heavier Mo isotope is preferentially adsorbed in the solution phase, pH has a more significant influence on isotope fractionation, and temperature and ionic strength are relatively insensitive. Differences in coordination environments between dissolved and adsorbed Mo during adsorption, i.e., attachment mode (inner- or outer-sphere) or molecular symmetry (e.g., coordination number and magnitude of distortion), are likely responsible for isotopic fractionation. For Fe, The study of equilibrium/kinetic Fe isotopic fractionation in aqueous Fe(II)-mineral is not simple. The interaction between aqueous Fe(II) and Fe (hydroxyl) oxides is complex and dynamic. The isotope effect is due to coupled electron and atom exchange between adsorbed Fe(II), aqueous Fe(II), and reactive Fe(III) on the surface of Fe (hydroxyl) oxide. For Zn, the heavier Fe isotope preferentially adsorbs on the solid phase, and pH and ionic strength are essential influencing factors. The difference in coordination environment may be the cause of isotope fractionation.

Achieving historically anticipated improvement in the performance of integrated circuits is challenging, due to the increasing cost and complexity of the required technologies with each new generation. To overcome this limitation, the exploration and development of novel interconnect materials and processes are highly desirable in the microelectronics field. Molybdenum (Mo) is attracting attention as an advanced interconnect material due to its small resistivity size effect and high cohesive energy; however, effective processing methods for such materials have not been widely investigated. Here, we investigate the electrochemical behavior of ions in the confined nanopores that affect the electrical properties and microstructures of nanoscale Mo and Mo–Co alloys prepared via template-assisted electrodeposition. Additives in an electrolyte allow the deposition of extremely pure metal materials, due to their interaction with metal ions and nanopores. In this study, boric acid and tetrabutylammonium bisulfate (TBA) were added to an acetate bath to inhibit the hydrogen evolution reaction. TBA accelerated the reduction of Mo at the surface by inducing surface conduction on the nanopores. Metallic Mo nanowires with a 130 nm diameter synthesized through high-aspect-ratio nanopore engineering exhibited a resistivity of (63.0 ± 17.9) μΩ·cm. We also evaluated the resistivities of Mo–Co alloy nanowires at various compositions toward replacing irreducible conventional barrier/liner layers. An intermetallic compound formed at a Mo composition of 28.6 at%, the resistivity of the Mo–Co nanowire was (58.0 ± 10.6) μΩ·cm, indicating its superior electrical and adhesive properties in comparison with those of conventional barriers such as TaN and TiN. Furthermore, density functional theory and non-equilibrium Green’s function calculations confirmed that the vertical resistance of the via structure constructed from Mo-based materials was 21% lower than that of a conventional Cu/Ta/TaN structure.

This work presents experimental data and modelling of the release of Mo from high-burnup spent nuclear fuel (63 MWd/kgU) at two different pH values, 8.4 and 13.2 in air. The release of Mo from SF to the solution is around two orders of magnitude higher at pH = 13.2 than at pH = 8.4. The high Mo release at high pH would indicate that Mo would not be congruently released with uranium and would have an important contribution to the Instant Release Fraction, with a value of 5.3%.Parallel experiments with pure non irradiated Mo(s) and XPS determinations indicated that the faster dissolution at pH = 13.2 could be the consequence of the higher releases from metallic Mo in the fuel through a surface complexation mechanism promoted by the OH− and the oxidation of the metal to Mo(VI) via the formation of intermediate Mo(IV) and Mo(V) species.

Using first-principles calculations, we have systematically studied thermodynamic stability, electronic structure and mechanical properties of Mo-Re binary alloys. The alloying element Re prefers to occupy the substitution position with a formation energy of 0.10 eV in Mo rather than the tetrahedron/octahedron interstitial position. The charge transfers are obviously present between Re and Mo atoms, which can be confirmed by the Bader charge analysis. The density of states (DOS) demonstrates that the d orbitals of Re and Mo atoms are hybridized, revealing that Re and its adjacent Mo atoms can form the directional bond containing covalent components. On the basis of above studies on the most stable occupancy structure, the mechanical quantities (the elastic constants Cij, bulk modulus B, Young’s modulus E, shear modulus G, Poisson’s ratio v, and B/G) have been analyzed for three Mo-Re alloys with the low Re content, which are Mo127Re1, Mo53Re1 and Mo15Re1, respectively. All these mechanical quantities of both Mo127Re1 and Mo53Re1 alloys are nearly the same as that of perfect Mo, while all these mechanical quantities of Mo15Re1 alloy are obviously larger or smaller than that of perfect Mo. This demonstrates that Mo15Re1 alloy has significantly different mechanical characteristics from Mo127Re1 and Mo53Re1 alloys as well as perfect Mo. These results can provide a significant reference for the application of Mo-Re alloys in future fusion fields.

The synthesis of two MO (Tl2O3–SiO2) Schiff bases complexes derived from MO (2-hydroxy,3-methoxy,5-nitro benzaldehyde)-1,2-ethylene diamine (L1) and MO (2-hydroxy-5-bromo benzaldehyde)-1,2-ethylene diamine (L2) is reported. Full characterization of these complexes was accomplished with elemental analyses, spectroscopic studies (IR, 1H NMR, EDX, TEM and SEM). photocatalytic and absorption properties of these nanoparticle (Tl2O3–SiO2-MoL1, Tl2O3–SiO2-MoL2) were compared. For this purpose, the ability of nanoparticles in the removal of MB was studied by UV–vis spectroscopy in the specified intervals. the equilibrium removal capacity of MB on Tl2O3–SiO2-MoL1 and Tl2O3–SiO2-MoL2 nanoparticles were equal to 5.5 and 23 mg/g, respectively. The benefits of this protocol are short reaction time, simple workup procedure, and high yields of products and Easy work‐up, chemical stability and simple recyclability are the most important advantages of this catalytic activity system.

Formate dehydrogenases catalyze the reversible oxidation of formate to carbon dioxide. These enzymes play an important role in CO2 reduction and serve as nicotinamide cofactor recycling enzymes. More recently, the CO2-reducing activity of formate dehydrogenases, especially metal-containing formate dehydrogenases, has been further explored for efficient atmospheric CO2 capture. In this sense, molecular hydrogen (H2) as the fuel of the future represents an efficient, cheap and environmentally friendly reducing agent when produced from renewable sources. Hydrogenases are enzymes that catalyze the reversible oxidation of H2. Herein, the functional interplay between the soluble [NiFe] hydrogenase from Cupriavidus necator and the molybdenum-dependent formate dehydrogenase from Rhodobacter capsulatus was investigated in a coupled biocatalytic system. H2-driven CO2 reduction (H2CO2R) using methyl viologen as an artificial electron mediator gave a higher product yield of formate than using NAD+ as the physiological electron mediator. The enzymes were stable under anaerobic conditions for 18 h, making the coupled reaction suitable for biotechnological purposes.

ABSTRACT: Cadmium (Cd) and high molybdenum (Mo) are injurious to the body. Previous research has substantiated that Cd and Mo exposure caused testicular injury of ducks, but concrete mechanism is not fully clarified. To further survey the toxicity of co-exposure to Cd and Mo in testis, 40 healthy 8-day-old Shaoxing ducks (Anas platyrhyncha) were stochasticly distributed to 4 groups and raised with basic diet embracing Cd (4 mg/kg Cd) or Mo (100 mg/kg Mo) or both. At the 16th wk, testis tissues were gathered. The characteristic ultrastructural changes related to apoptosis and ferroptosis were observed in Mo or Cd or both groups. Besides, Mo or Cd or both repressed nuclear factor erythroid 2-related factor 2 (Nrf2) pathway via decreasing Nrf2, Heme oxygenase-1 (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1), Glutamate-cysteine ligase catalytic subunit (GCLC) and Glutamate-cysteine ligase modifier subunit (GCLM) mRNA expression of and Nrf2 protein expression, then stimulated apoptosis by elevating Bcl-2 antagonist/killer-1 (Bak-1), Bcl-2-associated X-protein (Bax), Cytochrome complex (Cyt-C), caspase-3 mRNA expression, cleaved-caspase-3 protein expression and apoptosis rate, as well as reducing B-cell lymphoma-2 (Bcl-2) mRNA expression and ratio of Bcl-2 to Bax, and triggered ferroptosis by upregulating Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4), transferrin receptor (TFR1) and Prostaglandin-Endoperoxide Synthase 2 (PTGS2) expression levels, and downregulating ferritin heavy chain 1 (FTH1), ferritin light chain 1 (FTL1), ferroportin 1 (FPN1), solute carrier family 7 member 11 (SCL7A11) and glutathione peroxidase 4 (GPX4) expression levels. The most obvious changes of these indexes were observed in co-treated group. Altogether, the results announced that Mo or Cd or both evoked apoptosis and ferroptosis by inhibiting Nrf2 pathway in the testis of ducks, and co-exposure to Mo and Cd exacerbated these variations.

Alkanotrophic Rhodococcus strains from the Regional Specialised Collection of Alkanotrophic Microorganisms (acronym IEGM, www.iegmcol.ru) were screened for accumulation and sorption of MoO42- ions. Morphological and ultrastructural changes observed in bacterial cells during their cultivation in the molybdenum-containing medium are described. The species peculiarities, growth substrate preferences, and other physiological features allowing for the efficient removal of molybdate ions from the culture medium are discussed. Bioinformatics analysis of genes and proteins responsible for resistance to and accumulation of molybdenum was carried out using the sequenced R. ruber IEGM 231 and other published Rhodococcus genomes. n-Hexadecane growing strains with high (up to 85 %) accumulative activity and resistance to elevated (up to 20.0 mM) molybdenum concentrations were selected, which can be used for bioremediation of environments co-contaminated with heavy metals and hydrocarbons. Transmission electron microscopy and energy dispersive X-ray spectroscopy (TEM-EDX) revealed the ability of Rhodococcus not only to accumulate, but also to chemically convert soluble toxic molybdenum into insoluble compounds detected in the form of electron-dense nanoparticles.

Molybdenum is a refractory metal regarded as a promising basis for producing high-temperature components. However, the potential of manufacturing molybdenum-based structures by direct ink writing (DIW) has not been explored. In this study, three-dimensional porous molybdenum (Mo) and molybdenum-silicon (Mo–Si) composite lattices were fabricated using DIW with non-milled and milled powders. The effects of Mo powder morphology (resulting from milling) and chemical composition (alloying Mo with 3 and 10 wt% of Si) on the microstructure, phase composition, and static and cyclic compression properties at room temperature were investigated. Lattices fabricated from commercial spherical Mo powder exhibited the highest intra-filament porosity. Conversely, lattices fabricated from milled Mo powder were denser and had higher compressive strength, offset stress, and quasi-elastic gradient. Alloying Mo with Si during sintering resulted in composite lattices with Mo + Mo3Si microstructure. A low content of Mo3Si slightly decreased monotonic compression properties but did not affect the cyclic compression response compared to Mo lattices made from milled powder. In contrast, a high content of Mo3Si produced quasi-brittle lattices with reduced compressive strength and increased damage accumulation during cyclic loading. The cyclic behavior of all lattices was characterized by a ratcheting-dominated stress-strain response. Lattices fabricated from milled Mo and milled Mo-3 wt.%Si powders demonstrated superior performance compared to those fabricated from commercial spherical Mo and milled Mo-10 wt%Si powders. The results suggest that using milled powders can enhance the mechanical reliability and promote the use of DIW as preferred additive manufacturing technology for the fabrication of Mo–Si composite lattices.

The molybdenum and nitrogen content of super austenitic stainless steel in Cl− solution is shown to influence pitting resistance using immersion, electrochemical testing, and simulation. Variations in Mo and N content affect the defect density, resistance, and densification of the passive film, thereby reducing the number of pitting. A higher local pH associated with the pitting pits and an increase in NH3(NH4+) are the results of increased N content, which also slows the rate of pitting expansion. The combined effects of fewer actively reactive spots within the passive film retarded pitting, and decreased corrosion rates due to NH3(NH4+) mitigation of local acidity which serves to reduce the corrosion rate. The work function is improved to a greater extent when Mo and N are co-doped compared with individual Mo and N doping, and the adsorption energy is significantly increased when Mo and N are co-doped, indicating a synergistic role for Mo and N in the prevention of corrosion by Cl−.

As a key component of plant nitrogen-fixing enzymes and a variety of human coenzyme factors, molybdenum (Mo) plays an essential role in supporting both plant growth and human health. Soil is a key medium for the cycling of Mo in the biosphere. However, the driving anthropogenic and natural factors governing the spatial distribution of Mo in soil and their interactions are not well understood. To determine the factors that affect the spatial patterns of Mo in topsoil, 6980 samples were collected from the Longitudinal Range–Gorge Region (Linshui County, Sichuan Province, China). In this area, tall mountains are adjacent to deep valleys. Topsoil with enriched Mo is mostly distributed in mountainous areas. The most important factors influencing Mo in topsoil are soil parent materials (q = 0.482), altitude (q = 0.256), and soil type (q = 0.259). There are synergistic effects among the various driving factors [q(X1 ∩ X2) > Max[q(X1), q(X2)]]. The Geodetector model was used to validate the magnitude of the interaction effects. The contribution to interacting factors is nonlinearly enhanced when the contribution of a single factor was low (any two factors of aspect, road distance, land use type, and S). The contribution to interacting factors is enhanced bidirectionally when the contribution of a single factor was high (any two factors of altitude, soil type, soil parent material, OM, and TFe2O3). When the contribution of one factor is high and the other is low, the contributing to interacting factors is mostly enhanced bidirectionally and a few are nonlinearly enhanced.

New Ti alloys are being developed to obtain materials with better properties for biomedical applications. In order to avoid complications caused for the presence of Al and V ions in the blood stream, novel alloys have been developed without these two elements. Mo and Nb are two non-toxic β-stabilizing elements used in Ti alloys because they decrease the elastic modulus and improve corrosion resistance. Thus, this study investigated the influence of Nb addition in Ti-xNb-5Mo alloy (x = 0, 10, 20, 30 %wt) on microstructure, structure, and selected mechanical properties. The samples were characterized after annealing, and the results showed the decrease of α phase and growth of β phase with the addition of Nb. The ω phase in the alloy containing 20% Nb was also detected. The samples’ elastic modulus and microhardness tended to decrease with increasing of the β phase, except for the Ti–20Nb–5Mo alloy due to phase hardening ω. The average crystallite size of the α and β phases increased with the addition of Nb.

Molybdenum (Mo) demonstrates excellent industrial application potentials in micro-nano devices, which are inevitably subjected to shock loads during their application under harsh service environments. This study employs molecular dynamics (MD) simulations to investigate the shock responses of Mo under high-strain loading conditions with respect to the effects of crystal orientations. The findings reveal that monocrystalline Mo, along the shock direction of [111], exhibits inhomogeneous microstructure features characterized by significantly high-density and high-temperature localized regions. Once the rarefaction wave is produced, the physical parameters, including density and lateral pressure, will gradually decrease while normal pressure retains a residual value. The us-up, Pzz-up, and Pzz-V/V0 relations along the shock loading direction of [111] show deviations from those of [001] and [110] directions, with this difference being more pronounced for Pzz-V/V0. The formation of dislocations and the magnitude of shear stress experienced within the post-shock region are strongly dependent on crystal orientations. Specifically, an elevated probability of dislocation formation was observed along the [110] direction. Moreover, the magnitude of shear stress induced by shock loading along the [001] and [110] directions can exceed that of the [111] direction when the shock velocity is 1.5 km/s. The MD simulation results can serve as a valuable supplement to the investigations of mechanical properties pertaining to Mo.

Titanium (Ti) alloys have been widely used as bone implants, but challenges such as the stress shielding effect still compromise long-term clinical successes. To improve the mechanical properties of Ti, non-toxic alloying elements zirconium (Zr) and molybdenum (Mo) were added either alone or in combination to produce Ti–Mo–Zr alloys. The influence of Zr or Mo addition on the alloy properties, such as the microstructure and the corrosion resistance, were investigated. The cytocompatibility and osteointegration of prepared alloys were evaluated to determine the potential for bone repair. The results showed that Ti–10Zr displayed an acicular α′ phase, while Ti–12Mo and Ti–12Mo–10Zr comprised a metastable β phase. Due to the solid solution and phase precipitation strengthening effect of Zr and Mo elements, the prepared alloys showed higher microhardness and compressive yield strength when compared with commercially pure Ti (CP–Ti). Ti–12Mo–10Zr possessed the lowest Young's modulus, while CP-Ti and Ti–10Zr showed a comparable Young's modulus. The corrosion resistance was in the order of Ti–12Mo–10Zr > Ti–12Mo > CP-Ti > Ti–10Zr. Notably, all alloys showed good cytocompatibility and osteointegration, which were similar to those of CP-Ti. Taken together, due to excellent material and biological performance, Ti–12Mo–10Zr presents a promising material for bone repair.

Polycrystalline (PC) and single crystal (SC) molybdenum mirrors were irradiated with 98Mo+, 1H+, 4He+, 11B+ and 184W+. Energies were chosen to impact the optically active region (up to 30 nm deep) of Mo mirrors. Some surfaces were coated by magnetron sputtering either with B or W films 4–65 nm thick. The overall objective was to simulate the neutron-induced damage and transmutation (H, He), and the impact of H, He, B, W on the optical performance of test mirrors, and on fuel retention. In parallel, a set of PC Mo mirrors irradiated with 1.6 MeV 98Mo3+ to a damage of 2 dpa and 20 dpa was installed in the JET tokamak for exposure during deuterium-tritium campaigns. Data from spectrophotometric, ion beam and microscopy techniques reveal: (i) the irradiation decreased specular reflectivity, whereby the differences between PC and SC in reflectivity are very small, (ii) He is retained in bubbles within 25–30 nm of the subsurface layer in all irradiated materials, (iii) W, either deposited or implanted, decreases reflectivity, but the strongest reflectivity degradation is caused by B deposition. Laboratory studies show the correlation of damage and H retention. Several cycles of W deposition and its removal from SC-Mo mirrors by plasma-assisted methods were also performed.

Biodegradable metals and their alloys have gained significant attention as promising candidates for biomedical applications. Notably, Magnesium, Zinc, and Iron stand out as the most prominent biodegradable materials, prompting extensive research into novel alloy development. These metals exhibit inherent biodegradability, acceptable biocompatibility, and commendable mechanical integrity, rendering them suitable for implant use. In this comprehensive review, we delve into recent advancements in biodegradable implants within the biomedical domain, with a primary focus on orthopedic and cardiovascular applications. The paper extensively explores the in vivo and in vitro degradation behavior, mechanical properties, and corrosion mechanism of these materials. Additionally, we discuss progress in surface modification and fabrication techniques, vital in optimizing implant performance. However, certain limitations associated with alloying materials, especially Zinc and Iron, have hindered their widespread implementation. We underscore the importance of overcoming these challenges to unlock the full potential of these materials. Furthermore, we present the promise of new metals, such as Molybdenum, which exhibit remarkable properties, opening doors to implants with superior mechanical characteristics. Overall, this review emphasizes the growing significance of biodegradable metallic implants, showcasing their potential to address diverse clinical needs. By addressing material limitations and harnessing innovative metals, we pave the way for the development of implants with superior mechanical properties and desirable degradation rates, thus revolutionizing the field of biomedical applications.

This study used electrochemical deposition to make CeTe and CeTe-doped molybdenum. We deposited the films at varying concentrations of the dopant; (0.1–0.3) mol%. All the solutions used to deposit the thin films were prepared in distilled water. Adding molybdenum to cerium telluride boosts absorption rates. Film thickness decreased from 117.09 to 164.31 nm, lowering resistivity (11.24 to 08.23 ῼ.cm) and increasing conductivity (0.08 to 0.12 S/m). The pattern exhibit diffraction peaks at planes (111), (120), (121), and (131), which correspond to respective angles of 23.216°, 27.744°, 32.152°, and 36.182° The FTO substrates used for the synthesis may have been the cause of the unindexed peaks. The bandgap energy of cerium telluride is 1.20 eV, which narrows to 1.49 – 1.60 eV as molybdenum dopant concentration rises. The cerium telluride and CeTe-doped molybdenum have a lattice constant of 6.6490 and 6.6298 Å respectively. Cerium telluride doped molybdenum is a potential candidate for photovoltaic application.

Metal-dependent formate dehydrogenases (Me-FDHs) are highly active CO2-reducing enzymes operating at low redox potentials and employ either molybdenum or tungsten to reduce the bound substrate. This makes them suitable for electrochemical applications such as fossil-free production of commodity chemicals utilizing renewable energy. Electrocatalytic CO2 reduction by cathode-immobilized Me-FDHs has been recently demonstrated and rational protein engineering can be used to optimize Me-FDHs for various carbon reduction reactions. In the present study, CO2 reduction by soluble monomeric Escherichia coli formate dehydrogenase H (EcFDH-H) was demonstrated and the function of its nucleophilic selenocysteine residue as a transient ligand of a centrally bound molybdenum atom was investigated. Kinetic analysis of the wildtype enzyme revealed maximum CO2 reduction rates of 44 ± 6 s−1 at pH 5.8 that was decreased to 19% and 0% in the case of selenocysteine substitution with the structural homologues cysteine and serine, respectively. Further selenocysteine-to-cysteine substitution effects included an increased acid tolerance as well as stronger inhibition by nitrate and azide indicating a shift of the Mo oxidation state from IV to VI. Conversely, a destabilizing effect on the oxidized Mo(VI) center could be assigned to the native selenocysteine residue that may facilitate the observed efficient CO2 reduction by rapid transition between Mo oxidation states. Taken together, the performed characterization of EcFDH-H as a catalyst for CO2 reduction and the selenocysteine substitution analysis furthers the understanding of the active-site structure of Me-FDHs and thereby supports the development of more efficient biocatalysts for CO2 reduction.

This novel research is centered on synthesizing nickel telluride (NiTe) film through electrochemical deposition (ECD) technique. The film was doped with 0.1 M molybdenum at varying temperatures of 40 °C, 45 °C and 50 °C. The structure, morphology, elemental, optical, and electrical characteristics of the prepared samples has been investigated. Hexagonal crystal structure with prominent peaks was gotten from the X-ray diffractograms. The surface morphologies showed nanograins while the elemental compositions were confirmed from the EDX plots. Optical plots gave high absorbance and decreasing band gap energy values at increasing temperature. The electrical results gave improved electrical conductivity as the temperature increased. The prepared samples find useful application in optical and solar cell devices.

Soils developed in karst regions have naturally high background values of molybdenum (Mo) due to geological factors. However, the enrichment mechanism of Mo in these soils are not fully understood, making it challenging to assess their ecological risk and utilize Mo-rich land resources. To shed light on this issue, this study collected and analyzed data from the 1:50,000 geochemical survey in Guangxi, including 536,503 sets of soil data and 3043 sets of rock data, as well as 40 sets of carbonate rock-soil from typical karst regions. The results showed that soil Mo enrichment is highly correlated with the distribution of carbonate rocks in karst regions. The carbonate rocks in these regions contain Mo ranging from 0.03 to 1.06 mg·kg−1 (with a mean of 0.22 mg·kg−1). In comparison, the soil Mo derived from carbonate rocks can reach up to 6.00 mg·kg−1 (with a mean of 2.75 mg·kg−1), representing an average enrichment of soil Mo that is 24 times higher compared to the carbonate parent rock. The enrichment of soil Mo in karst regions is primarily controlled by secondary enrichment during the weathering process of carbonate. During the insoluble residue accumulation process, the dissolution of carbonate leads to a dramatic reduction in bedrock volume, and the adsorption of clay minerals and Fe minerals in insoluble residues plays an essential role in Mo enrichment during these stages. During the soil-forming stage of the insoluble residue, most Mo leaches into the water body due to the mineral transformation of insoluble residue. Consequently, as Fe–Mn nodules in soils become more enriched with increasing weathering intensity, some Mo is absorbed and passivated by iron and manganese oxides (hydroxides). Accordingly, the contribution of Fe–Mn nodules and the degree of leaching were closely related to the enrichment of soil Mo in karst regions. This study provides insights into the enrichment mechanisms of Mo in soils developed in karst regions, which will help to evaluate their ecological risk in these environments.

The recovery of rhenium from waste superalloys has always been a research focus. This study focuses on the performance of extraction of rhenium and its separation with molybdenum in alkali leaching solution of waste superalloy by methyl trioctylammonium chloride (N263). Minitab 17 Statistical Software (Trial version, Techmax, USA) was used to create a four-factor (N263 concentration, sec-octyl alcohols concentration, extraction time and organic to aqueous ratio (O/A ratio)) two-level orthogonal experiment table. According to the orthogonal experiment results of rhenium extraction and rhenium molybdenum separation coefficient, rhenium extraction model, rhenium molybdenum separation coefficient model and the corresponding regression equation were established. The rhenium extraction performance of N263 was investigated by the rhenium equilibrium curve and NaSCN concentration. It was found that the N263 concentration was the main factor affecting rhenium extraction, and the regression equation of rhenium extraction was Re extraction/% = 0.672 + 9.880 [N263]. Moreover, N263 concentration and O/A ratio are the main factors affecting rhenium molybdenum separation coefficient. The regression equation of rhenium molybdenum separation coefficient is β Re/Mo = 37.5 + 116.88* [N263] −24.3 *(O/A ratio) −20.62 [N263]*(O/A ratio). At the same concentration of the rhenium stripping agent, the rhenium stripping efficiency is perchloric acid > nitric acid > sodium thiocyanate. However, the strong oxidability of perchloric acid and nitric acid destroys the organic phase, making the organic phase produce visible destruction. The rhenium stripping was about 75.8 % with 40 times the theoretical amount of sodium thiocyanate. The results showed that Re was easy to be extracted in the alkali solution, but it was not easy to be stripped from the loaded N263 phase.

Preparing appropriate initial powders is a key factor in using laser powder bed fusion (L-PBF) for high-performance refractory materials. In this study, we developed a novel technology, the freeze-dry pulsated orifice ejection method (FD-POEM), for producing spherical molybdenum powders with controllable particle size and distribution and good flowability without melting. The Mo powders, which had unique mesh-structures, exhibited higher laser absorptivity than the dense ones. Pure Mo builds were fabricated using L-PBF. Fine MoO2 particles were formed and uniformly distributed along the grain boundaries and inside the equiaxed grains. High-resolution transmission electron microscopy revealed an interfacial orientation correlation between Mo [1 -1 -1]//MoO2 [0–1 0] and Mo (1 1 0)//MoO2 (0–1 2). The Vickers hardness of the Mo build increased compared to that of pure Mo owing to grain refinement and the oxide-dispersion-strengthening effect of in-situ MoO2. This study provides the basis for powder fabrication using FD-POEM and the processability of Mo parts via L-PBF in ultrahigh-temperature applications.

Background: Metal exposure were assumed to be closely related with declined renal function, but the conclusions were controversial. We employed diverse statistical models and assessed the association between metal mixture exposure and mild renal impairment. Methods: A total of 13 plasma metals were measured in 896 general population from Southern China. Subjects with estimated glomerular filtration rate within 60–89 ml/min/1.73 m2 and urinary albumin-creatinine ratio

Mo has been applied to nuclear material, in which H and carbon impurities are unavoidable. In view of this, we have studied the effect of carbon on the H retention in Mo using first-principles simulations. In perfect Mo, there is always repulsion between H and carbon, and impurity carbon cannot capture H atoms. With the appearance of vacancy in Mo, vacancy and carbon-vacancy cluster trap seven and six H atoms, respectively. This means that impurity carbon has little effect on the H vacancy capturing. Finally, we explore the H diffusion by considering the presence of one Mo-carbon layer in Mo. Away from the Mo-carbon layer, H jumps along the optimal route with a diffusion barrier of 0.12 eV. As H moves close and passes through the Mo-carbon layer, the H diffusion barrier is increased to 0.73 eV. Therefore, the repulsive interaction between H and carbon can increase the H energy barrier in the vicinity of the Mo-carbon layer, which prevent the H diffusion and permeation in Mo. The current results can explain the promoting mechanism of bubble formation due to impurity carbon implantation and help us design future Mo-based nuclear material.

Molybdenum (Mo) is considered as a promising plasma-facing material, which is expected to be used in the manufacture of critical components for the neutral beam injection (NBI) inductively coupled plasma (ICP) source. Hydrogen isotope retention and bubble formation are regarded as the unavoidable issues that degrade the metal properties in the ion source. In this work, the evolution of hydrogen bubbles in Mo pre-irradiated by 35 eV hydrogen ion energy during different annealing processes is studied through conductive atomic force microscopy (CAFM) observation. Meanwhile, the corresponding numerical simulation is applied to analyze the mechanisms of hydrogen bubble growth. It is found that the average size and density of hydrogen bubbles are enhanced with the increase of hydrogen ion fluence at 400 K in experiments and simulations. In the subsequent annealing process, it is demonstrated that annealing temperature has a certain effect on bubble growth and evolution. No obvious changes in bubbles are observed at the annealing temperature below 573 K. The average radius of hydrogen bubbles is increased by ∼1.0–2.5 nm in Mo annealed at 673–873 K. The bubble size increases with the rise of annealing temperature, indicating that the thermal annealing promotes the growth of bubbles. When the temperature rises above 873 K, the change in bubble size is not obvious. The simulation results indicate that temperature-induced changes in the internal pressure of hydrogen bubbles leads to the growth of bubbles, but this mechanism is not significant under high annealing temperatures due to the release of hydrogen from the surface.

Isotope technology is an ideal tool for tracing the sources of certain pollutants or providing insights into environmental processes. In recent years, the advent of multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) has enabled the precise measurement of various metal stable isotopes. Due to the presence of "fingerprint" properties in various environmental samples, metal stable isotopes have been applied to distinguish the source of contaminants effectively and further understand the corresponding environmental processes. The environmental fate of metal elements is strongly controlled by adsorption, an essential process for the distribution of elements between the dissolved and particulate phases. The adsorption of metal elements on mineral and organic surfaces significantly affects their biogeochemical cycles in the environment. Therefore, it is crucial to elucidate the fractionation characteristics of stable metal isotopes during the adsorption process. In this review, three typical transitional metal elements were selected, considering Mo as the representative of anionic species and Fe and Zn as the representative of cationic species. For Mo, the heavier Mo isotope is preferentially adsorbed in the solution phase, pH has a more significant influence on isotope fractionation, and temperature and ionic strength are relatively insensitive. Differences in coordination environments between dissolved and adsorbed Mo during adsorption, i.e., attachment mode (inner- or outer-sphere) or molecular symmetry (e.g., coordination number and magnitude of distortion), are likely responsible for isotopic fractionation. For Fe, The study of equilibrium/kinetic Fe isotopic fractionation in aqueous Fe(II)-mineral is not simple. The interaction between aqueous Fe(II) and Fe (hydroxyl) oxides is complex and dynamic. The isotope effect is due to coupled electron and atom exchange between adsorbed Fe(II), aqueous Fe(II), and reactive Fe(III) on the surface of Fe (hydroxyl) oxide. For Zn, the heavier Fe isotope preferentially adsorbs on the solid phase, and pH and ionic strength are essential influencing factors. The difference in coordination environment may be the cause of isotope fractionation., Competing Interests: Declaration of Competing Interest We declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Increased inputs of nitrogen from agricultural runoff, urbanization and suburbanization have resulted in degradation of water quality, including increased frequency and severity of hypoxia, in estuarine ecosystems. Much work has been conducted in recent years to characterize the spatial and temporal extent of hypoxia in coastal systems, but the historical record of hypoxia in such systems is much less well known. The current work examines the history of hypoxia in upper Narragansett Bay, an urbanized estuary in the northeastern U.S., through vertical profiles of geochemical markers in sediment cores. Concentrations of authigenic molybdenum indicate more frequent/ longer periods of hypoxia that are related to changes in population and anthropogenic inputs to the Bay from the surrounding watersheds. Cores from the urbanized upper bay, greatly affected by wastewater treatment facilities (WWTFs), indicate greater duration of hypoxia in the 20th century, with periods of hypoxia decreasing through mid-century and recurring thereafter. Trends of hypoxia are closely related to improvements and failures of WWTFs in surrounding communities. In Greenwich Bay, with a suburban watershed and only one WWTF, hypoxia increased substantially in parallel with growth of population in the surrounding watershed. Carbon and nitrogen concentrations and isotope values reflect increased nitrogen enrichment and productivity in the Bay in the 2nd half of the 20th century. These results can help inform study of the environmental responses to societal activities that may affect water quality., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Molybdenum (Mo) is an essential nutrient for leguminous plants, but the effects of Mo exposure on plant growth, especially in relation to soil microorganisms, are not fully understood. This study employed alfalfa (Medicago sativa L.) to evaluate the physiochemical responses to gradient soil Mo variations and explore the potential regulatory role of rhizosphere microorganism - arbuscular mycorrhizal fungi (AMF) in modulating Mo's impact on plant physiology, with a focus on metabolic pathways. The results showed that Mo exerted hormetic effect (facilitation at low doses; inhibition at high doses) on alfalfa growth, promoting biomass (below 90.94 mg/kg, with a 63.98 % maximum increase), root length (below 657.11 mg/kg, with a 39.29 % maximum increase), and plant height (below 304.03 mg/kg, with an 18.4 % maximum increase). Excess Mo (1000 mg/kg) resulted in a reduction in photosynthesis and biomass growth due to increased oxidative stress (p < 0.05). Within the stimulatory zones, AMF enhanced Mo accumulation in alfalfa, augmenting its phytological effects. Exceed the stimulatory zones, AMF enhanced alfalfa Fe uptake and reduced the generation of reactive oxygen species (ROS) induced by excess Mo by shifting the redox homeostasis-controlled enzyme from peroxidase (POD) to superoxide dismutase (SOD), thereby improving alfalfa's tolerance to Mo. Metabolomic analysis further revealed that AMF promoted the biosynthesis of indole acetic acid (IAA) and various amino acids in Mo-stressed alfalfa (p < 0.05), which accelerated alfalfa growth and mitigated Mo-induced phytotoxicity. These insights provide a foundation for developing sustainable management strategies for Mo-exposed soils using AMF inoculants, such as minimizing Mo fertilizer application in Mo-deficient soils and facilitating the reclamation of Mo-contaminated soils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Soil molybdenum (Mo) levels can reach ecologically hazardous levels. China has not yet established the relevant thresholds, posing challenges for environmental management. Therefore, we present our data relevant to Mo toxicity for several important species. By normalizing soil properties, we obtained a correlation model of Mo toxicity to Hordeum vulgare, as well as 31 models for the toxicity of other elements including Cu and Ni to invertebrates and microbial processes. Using interspecies correlation estimation (ICE) extrapolation, the sensitivity coefficient (0.12-0.71) for five plants were found. For invertebrates and microbial processes lacking Mo data, we used regression analysis to establish Mo toxicity models based on the soil quantitative ion character-activity relationships (s-QICAR; R 2 =0.70-0.95) and known toxicities of other metal elements to invertebrate and microbial processes. Furthermore, combining species sensitivity distribution calculations, the HC 5 values for protecting 95% of soil species from Mo in three typical soil scenarios in China were calculated. After correction, the predicted no-effect concentrations were 6.8, 4.8, and 3.4 mg/kg, respectively. This study innovatively combined ICE and s - QICAR to derive soil Mo thresholds. Our results can provide a basis for decision-making in the assessment and management of soil Mo pollution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

There are many heavy metal stresses in agricultural biological systems, especially cadmium (Cd) stress, which prevent the full growth of plants, lead to a serious decline in crop yield, and endanger human health. Molybdenum (Mo), an essential nutrient element for plants, regulates plant growth mainly by reducing the absorption of heavy metals and protecting plants from oxidative damage. The aim of this study was to determine the protective effect of Mo (1 μM) application on wheat plants under conditions of Cd (10 μM) toxicity. The biomass, Cd and Mo contents, photosynthesis, leaf and root ultrastructure, antioxidant system, and active oxygen content of the wheat plants were determined. Mo increased the total chlorophyll content of wheat leaves by 43.02% and the net photosynthetic rate by 38.67%, and ameliorated the inhibitory effect of cadmium on photosynthesis by up-regulating photosynthesis-related genes and light-trapping genes. In addition, Mo reduced the content of superoxide anion (O 2 •- ) by 16.55% and 31.12%, malondialdehyde (MDA) by 20.75% and 7.17%, hydrogen peroxide (H 2 ) by 24.69% and 8.17%, and electrolyte leakage (EL) by 27.59% and 16.82% in wheat leaves and roots, respectively, and enhanced the antioxidant system to reduce the burst of reactive oxygen species and alleviate the damage of Cd stress on wheat. According to the above results, Mo is considered a plant essential nutrient that enhances Cd tolerance in wheat by limiting the absorption, accumulation and transport of Cd and by regulating antioxidant defence mechanisms. ENVIRONMENTAL IMPLICATION: Cadmium (Cd)，is one of the most toxic heavy metals in the environment, and Cd pollution is a global environmental problem that threatens food security and human health. Molybdenum (Mo), as an essential plant nutrient, is often used to resist environmental stress. However, the mechanism of Mo treatment on wheat subjected to Cd stress has not been reported. In this study, we systematically analysed the effects of Mo on the phenotype, physiology, biochemistry, ultrastructure and Cd content of wheat subjected to Cd stress, and comprehensively analysed the transcriptomics. It not only reveals the mechanism of Mo tolerance to Cd stress in wheat, but also provides new insights into phytoremediation and plant growth in Cd-contaminated soil.2 ) by 24.69% and 8.17%, and electrolyte leakage (EL) by 27.59% and 16.82% in wheat leaves and roots, respectively, and enhanced the antioxidant system to reduce the burst of reactive oxygen species and alleviate the damage of Cd stress on wheat. According to the above results, Mo is considered a plant essential nutrient that enhances Cd tolerance in wheat by limiting the absorption, accumulation and transport of Cd and by regulating antioxidant defence mechanisms. ENVIRONMENTAL IMPLICATION: Cadmium (Cd)，is one of the most toxic heavy metals in the environment, and Cd pollution is a global environmental problem that threatens food security and human health. Molybdenum (Mo), as an essential plant nutrient, is often used to resist environmental stress. However, the mechanism of Mo treatment on wheat subjected to Cd stress has not been reported. In this study, we systematically analysed the effects of Mo on the phenotype, physiology, biochemistry, ultrastructure and Cd content of wheat subjected to Cd stress, and comprehensively analysed the transcriptomics. It not only reveals the mechanism of Mo tolerance to Cd stress in wheat, but also provides new insights into phytoremediation and plant growth in Cd-contaminated soil., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ti laminated composites were successfully prepared by employing metallic additive powders between Ti sheets, and using the spark plasma sintering process. Mo, Cr, Si and Co were inserted between Ti layers, and spark plasma sintering was carried out at 1250 °C. Regarding the Ti–Si laminated composite, the final products comprised divided sintered Si and Ti sheets which were not stuck together. A new sample was prepared at a temperature higher than 1850 °C with the appropriate bonding of layers. The XRD patterns revealed dominant Ti peaks in Ti–Cr and Ti–Mo, while, in the intermetallic compounds between Ti and metallic additives of Co, Si peaks were dominant. The FESEM images taken from the samples' cross-section demonstrated the ultra-short-range diffusion of Mo into the Ti sheets. The process was amplified from Cr additives to Co; it appeared that the laminated structure was changed into a uniform one of the Ti–Co alloy. Regarding the Si additive, the laminated structure turned into the intermetallic of Ti5Si3–Ti5Si4 islands and seemed to be the composite. An analysis of the mechanical properties also showed the highest Vickers hardness of 1121 ± 32 HV1 for the Ti–Si sample in terms of the intermetallic nature of the formed sample, whereas the highest bending strength of 998 ± 16 MPa was achieved in the Ti–Cr laminated composite.

A comparative study was carried out on GTAW AISI 316 welds fabricated by three different filler metals including ER-317M, ER-316 and ER-308. Filler metals were selected in a way to induce varying Molybdenum (Mo) concentrations in the weld metal, so that the effect of Mo on the microstructural, mechanical and corrosion behavior of the welds was investigated. Microstructural studies revealed that as Mo concentration increased in the weld metal, the dendritic morphology of this zone gradually was changed from cellular dendritic to columnar dendritic and a noticeable amount of austenitic phase and precipitations were formed. Mo-containing ER-316 and ER-317M welds showed appreciable amount of Mo- and Cr-rich carbides such as (Fe,Cr)23C6 which formed at the grain boundaries of δ-ferrite phase resulting in increased the hardness and strength of welded samples. The highest microhardness value of 188 HV and yield strength of 330 MPa belonged to ER-317M welds containing the highest Mo concentration. Also, corrosion resistance of the welds significantly improved by increasing Mo concentration and a minimum corrosion rate of 4.178 mm/year was accounted for ER-317M welds in which, the formation of passive film was more facilitated due to the higher concentration of Mo.

Mo-KIT-6 catalysts precursors obtained by direct hydrothermal synthesis using different Si/Mo molar ratios (10, 20, 30) were evaluated in the production of biodiesel from the transesterification of soybean oil with methanol. A 22 + 3PtCt factorial design was used to evaluate the influence of alcohol/oil and Si/Mo ratios on biodiesel yield. ANOVA statistical analysis showed that Si/Mo ratio was the most significant variable. The factorial design showed that the optimal conditions for maximizing the biodiesel yield are: using the 10_Mo-KIT-6 catalyst, and an alcohol/oil ratio of 20/1 at 150 °C for 3 h. However, using the 20_Mo-KIT-6 catalyst with an alcohol/oil ratio of 15/1 the biodiesel yield is close to the maximum, having the advantage of using a lower amount of methanol, which means that the separation of non-reacted alcohol will consume less energy.

Shells of the fast-growing bivalve Pecten maximus serve as a geochemical archive for the reconstruction of past phytoplankton dynamics. Specifically, high-resolution, temporally accurately aligned molar barium-to-calcium (Ba/Cashell), molybdenum-to-calcium (Mo/Cashell) and lithium-to-calcium ratios (Li/Cashell) of the shell calcite revealed distinct peaks which are closely linked to phytoplankton dynamics. Yet, the development and applicability of these geochemical proxies is still at an early stage and needs further calibration. In this study, we examined the relationship between the timing and magnitude of Ba/Cashell, Mo/Cashell and Li/Cashell peaks of P. maximus and the occurrence of various phytoplankton species (diatoms and dinoflagellates) from a statistical perspective. Studied shell samples (three specimens per calendar year) as well as detailed phytoplankton observation data were derived from the well-studied costal ecosystem of the Bay of Brest (France) over three years (2011, 2012 and 2019). An algorithm-based pseudo-random sampling simulation technique was established that analyzed the complex phytoplankton datasets with respect to the profiles of Ba/Cashell, Mo/Cashell and Li/Cashell to identify potential patterns between phytoplankton and trace element time-series. The simulation results indicate that the timing and magnitude of Ba/Cashell, Mo/Cashell and Li/Cashell peaks agreed best with the occurrence of specific phytoplankton blooms that developed ca. one to two weeks earlier. The data suggest that the formation of transient Ba/Cashell peaks had a plurispecific origin, i.e., potentially linked to blooms of ingestible diatom, dinoflagellate and flagellate species enriched in Ba that occurred 8 to 12 days earlier. Observed peaks in Mo/Cashell profiles demonstrably followed the timing and intensity of blooms of the dominant dinoflagellate genus Gymnodinium spp. after a short time lag of around 8 days, potentially linked to an enhanced enzyme activity of nitrate reductase that requires the presence of Mo in the dinoflagellate cells. In addition, Mo/Cashell peaks agreed with periods of diatom aggregate formation which were hypothesized to induce the formation of Mo/Cashell peaks in scallop shells. Li/Cashell profiles revealed similar patterns as large blooms of the diatom Chaetoceros spp. as well as to neurotoxin producing diatoms of the genus Pseudo-nitzschia when considering a short time lag of 8 to 12 days. These findings highlight the great potential of using Ba/Cashell, Mo/Cashell and Li/Cashell chronologies in P. maximus shells as proxies of past phytoplankton dynamics.

The diabetogenic effects of metals including lead (Pb), mercury (Hg), cadmium (Cd), and molybdenum (Mo) have been reported with poorly identified underlying mechanisms. The current study assessed the effect of metals on the roles of oxidative stress, apoptosis, and inflammation in beta pancreatic cells isolated from CD-1 mice, via different biochemical assays. Data showed that the tested metals were cytotoxic to the isolated cells with impaired glucose stimulated insulin secretion (GSIS). This was associated with increased reactive oxygen species (ROS) production, lipid peroxidation, antioxidant enzymes activities, active proapoptotic caspase-3 (cas-3), inflammatory cytokines interleukin–6 (IL-6) and tumor necrosis factor-alpha (TNF-α) levels in the intoxicated cells. Furthermore, antioxidant-reduced glutathione (GSH-R), cas-3 inhibitor z-VAD-FMK, IL-6 inhibitor bazedoxifene (BZ), and TNF-α inhibitor etanercept (ET) were found to significantly decrease metal-induced cytotoxicity with improved GSIS in metals’ intoxicated cells. In conclusion, oxidative stress, apoptosis, and inflammation can play roles in metals–induced diabetogenic effect.

Alkyne metathesis in multicomponent catalytic systems, although subject to changes, is still dominated by molybdenum hexacarbonyl as a source of Mo(0). Our findings show that this coordination compound is relatively inert under metathesis conditions, which results in noticeably long induction of catalytic activity, and the kinetics of this transformation can greatly benefit from switching to more labile Mo(0) complexes. Several easily obtainable ones were tested and [Mo(CO)3(py)3] has been chosen as the one exhibiting the most desired features, i.e. nearly instant catalytic activity and relative stability in the air.

The paper presents the experimental studies to determine the corrosion compatibility of various base materials of the capillary-porous structures (CPS) with a liquid tin-lithium alloy under high temperatures. The experiments were carried out with Li-Sn alloy and the samples of vanadium, tungsten, molybdenum, tantalum, and stainless steel. These materials were selected as the candidate ones for the matrix of Li-Sn CPS prototypes. Manufacture of Li-Sn alloy and experiments were carried out at test bench VIKA. The ranges of the temperatures was: 600 °C–800 °C for stainless steel, and 850 °C–1000 °C for other metals; exposure time for every temperature step was up to 100 h.The implemented activities included manufacture of Sn-Li alloys with various lithium contents (25 at.% and 27 at.%), characterization of the samples, experiments to study compatibility of liquid tin-lithium with vanadium, tungsten, molybdenum, tantalum at temperatures of 850 °C–1000 °C, and stainless steel at temperatures of 600–800 °C. As a result of the performed activities, molybdenum and tungsten were selected as the most corrosion resistant materials in respect to Li-Sn alloys.

Pure molybdenum produced by additive laser powder bed fusion (LPBF) processes has a coarse, epitaxially-grown columnar grain structure with cracks located at high-angle grain boundaries, which are embrittled through oxygen segregation. The tensile strength of these pure molybdenum specimens is only 50 MPa, or 11% of the strength of powder metallurgically sintered, deformed, and recrystallized molybdenum. Alloying molybdenum with carbon can reduce cracks, increase density to 99.5%, and thus increase tensile strength to 650 MPa. The addition of carbon prevents embrittled grain boundaries and high residual porosity by outgassing oxygen, trapping any residual oxygen in the oxygen-soluble Mo2C carbide, and increasing the grain boundary surface on which the oxygen is distributed. In this study, we investigated the grain size, tensile strength, and hardness of five different molybdenum-carbon alloys produced via LPBF at constant process parameters. Our alloys ranged from pure molybdenum to 2.2 wt% carbon, which corresponds to a near-eutectic composition. In the absence of extrinsic nucleant particles in the melt, the relationship between grain size and solute concentration—and thus the growth restriction factor—follows an inverse exponential Arrhenius-type equation. We attributed grain refinement at higher carbon contents to increasing thermal and constitutional supercooling. The supercooling allows grains to nucleate and grow on the underlying solidified layer, where the fastest growth direction 〈100〉 is better aligned to the thermal gradient than that of the epitaxially growing grains.

Background: Metal exposures have been reported to be related to the progress of metabolic syndrome (MetS), however, the currents results were still controversial, and the evidence about the effect of multi-metal exposure on MetS were limited. In this study, we intended to evaluate the relationships between metal mixture exposure and the prevalence of MetS in a mid-aged and older population of China. Methods: The plasma levels of 13 metals (aluminum, magnesium, calcium, iron, manganese, cobalt, copper, arsenic, zinc, selenium, cadmium, molybdenum and thallium) were detected by inductively coupled plasma mass spectrometry (ICP-MS) in 1277 adults recruited from the Eighth Affiliated Hospital of Sun Yat-Sen University (Shenzhen, China). Logistic regression, the adaptive least absolute shrinkage and selectionator operator (LASSO) penalized regression analysis and restricted cubic spline (RCS) analysis were used to explore the associations and dose-response relationships of plasma metals with MetS. To evaluate the cumulative effect of metals, the Bayesian Kernel Machine Regression (BKMR) model was applied. Results: The concentrations of magnesium and molybdenum were lower in the MetS group (p

A spectrophotometric routine was used to study the effect of surfactant micellization on the oxidation of mercaptobenzothiazole (MBTZ) by bioinorganic molybdenum complex at 301 K and an absorption maxima of 560 nm. It follows an acid dependent oxidative pathway that is medium-sensitive. Charge distribution from the reaction species contributes to the redox retardation, resulting in a downturned primary salt effect with an unenhanced reaction rate. Alteration of the reaction medium with ethanol led to a lowering of oxidation time as the charge catalysis was promoted by a drop in the system permittivity. Likewise, the micellization of cetyltrimethylammonium bromide in the system increased the oxidation rate of the MBTZ due to the high impact of hydrophobic and ion interaction between the micelle and substrates. First order reaction kinetics was observed in the concentration of the redox partners and a 2:2 (complex: MBTZ) stoichiometry was obtained with the involvement of benzothiazyl radical, which resulted in the formation of benzothiazyl disulphide and a Mo2+ deactivated complex. The occurrence of counterion catalysis is pronounced in the reaction system. The standard enthalpy (31.52 ± 0.11 kJ mol−1) and Gibbs energy (74.54 ± 0.13) kJ mol−1 suggest that the process is endothermic dependent. The investigation of surfactant micellization effect on the reaction medium was quantitatively ascertained from the Piszkiewicz model of the complex interaction sequence.

Excess molybdenum (Mo) and cadmium (Cd) are widespread environmental and industrial metal pollutants. To evaluate the combined effects of Mo and Cd on calcium homeostasis and autophagy in duck kidneys. 160 healthy 7-day-old ducks (Anas platyrhyncha) were randomized into 4 groups and given to a basic diet, adding various doses of Mo or/and Cd for 16 weeks. On the 4th, 8th, 12th and 16th weeks, kidney tissues were collected. The study exhibited that Mo or/and Cd caused histological abnormality, reduced the activities of Ca2+ ATPase, Mg2+ ATPase, Na+-K+ ATPase and Ca2+-Mg2+ ATPase, K and Mg contents, and increased Na and Ca contents, upregulated CaMKKβ, CaMKIIɑ, CaN, IP3R, GRP78, GRP94, CRT mRNA levels and CaMKIIɑ, CaN, IP3R protein levels. Moreover, exposure to Mo or/and Cd notably promoted the amount of autophagosomes and LC3II immunofluorescence, upregulated AMPKα1, ATG5, Beclin-1, LC3A, LC3B mRNA levels and Beclin-1, LC3II/LC3I protein levels, downregulated mTOR, Dynein, P62 mRNA levels and P62 protein level. The changes of above indicators in combined group were more obvious. Overall, the results suggest that Mo and Cd co-exposure may can synergistically induce nephrotoxicity via causing calcium homeostasis disorder and autophagy in ducks.

Detecting dopamine (DA) is critical for early diagnosis of neurological and psychiatric disorders. However, the presence of other catecholamine neurotransmitters with structural similarities to DA causes significant interference in its detection. Herein, we introduce S stripping defects via laser-induced MoS 2 to functionalize MoS 2 electrodes and improve their selectivity for DA electrochemical detection. The sensing results show its excellent immunity to interference from other neurotransmitters, ensuring the preservation of the DA electrochemical signal even in the mixed neurotransmitters such as acetylcholine (ACh), γ-aminobutyric acid (GABA), epinephrine (EP), norepinephrine (NP), and serotonin (5-HT). DFT calculations further reveal that the negatively charged S-stripping defects enhance DA adsorption on the surface of the functionalized MoS 2 electrode, contributing to its excellent performance. Moreover, this functionalized electrodes successfully monitor DA released from living PC12 cells in the presence of other interference, highlighting its potential applicability in intercellular signaling communication., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Molybdenum (Mo) contamination of farmland soils poses health risks due to Mo accumulation in crops like rice. However, the mechanisms regulating soil availability and plant uptake of Mo remain poorly understood. This study investigated Mo uptake by rice plants, focusing on Mo speciation and isotope fractionation in soil and rice plants. Soil Mo species were identified as sorbed Mo(VI) and Fe-Mo(VI) using X-ray absorption spectroscopy (XAS). Soil submergence during rice cultivation led to the reductive dissolution of Fe-associated Mo(VI) while increasing sorbed Mo(VI) and Ca-Mo(VI). Soil Mo release to soil solution was a dynamic process involving continuous dissolution/desorption and re-precipitation/sorption. Mo isotope analysis showed soil solution was consistently enriched in heavier isotopes during rice growth, attributed to re-sorption of released Mo and the uptake of Mo by rice plants. Mo was significantly associated with Fe in rice rhizosphere as sorbed Mo(VI) and Fe-Mo(VI), and around 60 % of Mo accumulated in rice roots was sequestrated by Fe plaque of the roots. The desorption of Mo from Fe hydroxides to soil solution and its subsequent diffusion to the root surface were the key rhizosphere processes regulating root Mo uptake. Once absorbed by roots, Mo was efficiently transported to shoots and then to grains, resulting in heavier isotope fractionation during the translocation within plants. Although Mo translocation to rice grains was relatively limited, human exposure via rice consumption remains a health concern. This study provides insights into the temporal dynamics of Mo speciation in submerged paddy soil and the uptake mechanisms of Mo by rice plants., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Shan-Li Wang reports financial support was provided by National Science and Technology Council. Shan-Li Wang reports a relationship with National Synchrotron Radiation Research Center that includes: non-financial support. Shan-Li Wang reports a relationship with National Synchrotron Light Source II that includes: non-financial support. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Symbiotic nitrogen fixation can reduce the impact of agriculture on the environment by reducing fertilizer input. The rapid development of nanomaterials in agriculture provides a new prospect for us to improve the biological nitrogen fixation ability of leguminous crops. Molybdenum is an important component of nitrogenase, and the potential application of MoO 3 NPs in agriculture is largely unexplored. In this study, on the basis of verifying that MoO 3 NPs can improve the nitrogen fixation ability of soybean, the effects of MoO 3 NPs on the symbiotic nitrogen fixation process of soybean were investigated by using dynamic transcriptome and targeted metabolome techniques. Here we showed that compared with conventional molybdenum fertilizer, minute concentrations of MoO 3 NPs (0.01-0.1 mg kg -1 ) could promote soybean growth and nitrogen fixation efficiency. The nodules number, fresh nodule weight and nitrogenase activity of 0.1 mg kg -1 were increased by 17 %, 14 % and 27 %, and plant nitrogen accumulation increased by 17 %. Compared with conventional molybdenum fertilizer, MoO 3 NPs had a greater effect on apigenin, kaempferol and other flavonoid, and the expression of nodulation related genes such as ENOD93, F3'H. Based on WGCNA analysis, we identified a core gene GmCHS9 that was positively responsive to molybdenum and was highly expressed during MoO 3 NPs induced nodulation. MoO 3 NPs could improve the nitrogen fixation ability of soybean by promoting the secretion of flavonoids and the expression of key genes. This study provided a new perspective for the nano-strengthening strategy of nodules development and flavonoid biosynthesis by molybdenum., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024. Published by Elsevier B.V.)

By taking molybdenum (Mo) having favorable metallurgical compatibility with both titanium and iron as the interlayer material, the butt joint of TA1/Q235B layered bimetallic sheet with thickness of 6 mm was prepared by utilizing narrow gap multi-pass laser welding with low heat input. Mo generally can favorably isolate Ti from Fe, meanwhile the transition zone of Mo and steel adjacent to Mo interlayer was softened according to the results of microhardness test. The results of face bending testing showed that the softened zone was beneficial to the mechanical properties of the welded joint, which could restrict the crack propagation along the interface of Mo/steel in fusion zone so that fracture appeared in the BM side. The microstructures of the softened zone exhibited a low dislocation density observed by a transmission electron microscope (TEM), which may be the main reason leading to a low microhardness. In additon, Mo interlayer was confined in a small zone, which only accounted for about 6.5% of the total area of cross section of the fusion zone while a small amount of FeTi and λ brittle intermetallic compounds (IMCs) still appeared around the Mo/steel interface in fusion zone. The tensile strength of the welded joint was 467 MPa, which took up about 93% that of base metal. The results of this paper will help guide endeavours for the fabrication of pipes and containers made of Ti/steel bimetallic sheets.

In this work, Ti6Al4V alloy was treated by a duplex treatment of double glow plasma surface molybdenizing-laser surface texturing (LST) aiming to realize surface strengthening and manipulate its tribological behavior. The double glow plasma surface alloying (DGPSA) with molybdenum (Mo) was firstly conducted on the Ti6Al4V alloy and followed by LST to prepare round dimple-shape texture with a density of 5%, 7%, 11%. The results showed that Mo and Mo/Ti solid solution phases were detected in the Mo-layer by X-ray diffraction (XRD), the received Mo-layer with a thickness of about 13 μm was uniform and compact. Double glow plasma surface molybdenizing significantly improved the surface hardness and elastic modulus of Ti6Al4V alloy by nanoindentation test. The gradient distributed Mo-layer was tightly adhered to the Ti6Al4V alloy matrix through scratching and indentation tests. Duplex treated Ti6Al4V alloy with a 5% texture density suggested better wear resistance in comparison to the untreated Ti6Al4V alloy, which was confirmed by a 48.7% lower specific wear rate than that of Ti6Al4V alloy. Taking advantages of DGPSA and LST, duplex treatment of double glow plasma surface molybdenizing-laser surface texturing was established to create on the working surface of Ti6Al4V alloy with promisingly improved tribological behavior.

Background: Exposure to metals/metalloids from both the natural environment and anthropogenic sources have a complex influence on human health. However, relatively few studies have explored the relations of exposure to multiple metals/metalloids with mortality. Therefore, this prospective study aims to examine the relations of multiple metal/metalloids exposures with all-cause and cardiovascular disease (CVD) mortality. Methods: A total of 6155 participants within the Dongfeng-Tongji (DF-TJ) cohort were involved in this analysis, which were followed for mortality until December 31, 2018. We applied inductively coupled plasma mass spectrometry (ICP-MS) to measure baseline plasma concentrations of 23 metals. We utilized Cox regression models to calculate the hazard ratios (HRs) for all-cause and CVD mortality associated with metal concentrations. We proposed plasma metal score to assess the simultaneous exposure to multiple metals through summing each metal concentration weighted by the regression coefficients with all-cause mortality. Results: During the follow-up (mean duration, 9.8 years), we ascertained 876 deaths, including 416 deaths of CVD (157 deaths of coronary heart disease and 259 deaths of stroke). In the multiple-metals model, after adjusting for potential confounders, plasma copper, molybdenum, and vanadium were positively associated with all-cause mortality, whereas manganese, selenium, and thallium were negatively associated with the risk of all-cause mortality, with adjusted HRs (95% Confidence Interval, CI) of the fourth quartiles were 1.73 (1.42–2.11, P-trend

Growing evidences reveal that Nrf2-mediated antioxidant defense response and mitophagy are involved in the toxic mechanism of heavy metals, but the effects of molybdenum (Mo) and cadmium (Cd) co-exposure on Nrf2-mediated antioxidant defense response and mitophagy in duck hypothalamus have yet to be elucidated. Herein, 40 healthy 7-day-old ducks were randomly assigned to 4 groups and fed diets containing different doses of Mo or/and Cd for 16 weeks, respectively. The data demonstrated that Mo or/and Cd notably elevated their contents in hypothalamus, decreased Cu, Fe, Zn and Se contents, caused pathological damage and oxidative stress accompanied by elevating MDA content and reducing CAT, T-AOC, T-SOD, GSH-Px activities. Moreover, Mo or/and Cd not only restrained Nrf2 pathway by decreasing Nrf2, HO-1, NQO1, GST, CAT, SOD1, GCLM mRNA expression levels and Nrf2 protein expression level, but also disturbed mitochondrial dynamics and triggered PINK1/Parkin-mediated mitophagy by enhancing MFF, PINK1, Parkin, Bnip3, LC3A, LC3B mRNA expression levels and PINK1, Parkin, LC3B-II/LC3B-I protein expression levels, inhibiting Mfn1, Mfn2, OPA1, P62 mRNA expression levels and P62 protein expression level, and facilitating the colocalization between LC3 and HSP60. The changes of above factors were most remarkable under Mo and Cd co-treatment. Overall, the results elucidate that Mo and Cd can synergistically inhibit Nrf2-mediated antioxidant defense response and activate PINK1/Parkin pathway-dependent mitophagy in duck hypothalamus, whose mechanism is somehow related to Mo and Cd accumulation.