Search

Novel bismuth oxide/sodium bismuth molybdate nanocomposites (NCs), Bi 2 O 3 @NaBi(MoO 4) 2 , were developed successfully via simple methods. Advanced analyses revealed that the NCs were composed of Bi 2 O 3 and NaBi(MoO 4) 2 particles at the nanoscale, below 10 nm, in a combination of amorphous and crystalline forms. In this work, these NCs were utilized as lithium-ion battery anode materials for the first time, demonstrating exceptional electrochemical performances, including high capacity, superior capacity retention, high coulombic efficiency, excellent rate capacity, and pseudo-capacitance behavior. For instance, Bi 2 O 3 @NaBi(MoO 4) 2 NCs prepared at 1 h and 3 h of reaction time delivered a reversible charge capacity of 1052 and 1034 mAh g−1 after 200 cycles at current densities of 0.1 A g−1 with a capacity retention of 110 and 129 %, respectively. Notably, all the NCs anodes exhibited an excellent initial coulombic efficiency of above 80 %. Materials characterizations and electrochemical analysis revealed that the improved electrochemical properties of the NCs were attributed to their unique architectures, which featured nanostructures, molybdate components, and a small amount of amorphous phase. In addition, the significant capacity increase could be due to the electrochemical milling effect, the in situ formation of metallic particles, and the role of Mo metal in the NCs anodes as the catalysts for Li 2 O decomposition during cycling. It concluded that Bi 2 O 3 @NaBi(MoO 4) 2 NCs have great potential as advanced anodes for Li-ion storages. [Display omitted] • Bi 2 O 3 @NaBi(MoO 4) 2 materials are prepared via facile methods. • Bi 2 O 3 @NaBi(MoO 4) 2 materials consist of both amorphous and crystalline structures. • Bi 2 O 3 @NaBi(MoO 4) 2 materials are comprised of a lot of nanoparticles below 10 nm. • Bi 2 O 3 @NaBi(MoO 4) 2 anodes exhibit high initial coulombic efficiency (>80 %). • Bi 2 O 3 @NaBi(MoO 4) 2 anodes demonstrate a fast and stable Li-ion storage ability. [ABSTRACT FROM AUTHOR]

Recycling of spent lead‐acid batteries (LABs) is extremely urgent in view of environmental protection and resources reuse. The current challenge is to reduce high consumption of chemical reagents. Herein, a closed‐loop spent LABs paste (SLBP) recovery strategy is demonstrated through Na2MoO4 consumption‐regeneration‐reuse. Experimental and DFT calculations verify that MoO42− competes Pb/Ca ions and weakens the metal‐oxygen bond of PbSO4/CaSO4.2H2O in SLBP, facilitating PbMoO4/CaMoO4 formation and 99.13 wt% of SO42− elimination. Pb of 99.97 wt% is obtained as zero‐carbon precursors (PbO2 and PbMoO4) by green leaching coupled with re‐crystallization. The regeneration of Na2MoO4 is realized at 600 ℃ using LABs polypropylene shells and NaOH as reagents. Compared with the traditional smelting technologies, the temperature is reduced from ＞1000 to 600 °C. The extraction of Na2MoO4 require only water, and satisfactory re‐used desulfurization efficiency (98.67 wt%) is achieved. For the residual Na2MoO4 after first SLBP desulfurization, the desulfurization efficiency remains above 97.36 wt% after adding fresh reagents for two running cycles. The new principle enables the reuse of 99.83 wt% of Na2MoO4 and the recycling of 95.27 wt% of Pb without generating wastewater and slags. The techno‐economic analysis indicates this strategy is efficient, economical, and environmentally‐friendly. [ABSTRACT FROM AUTHOR]

MoS 2 nanosheets were vertically grown in S-doped graphitic carbon nitride (g-C 3 N 4) nanosheets to enhance electrochemical performance. Dicyandiamide was used as a precursor while sodium molybdate and thioacetamide were as additives, and sulfur was introduced into the carbon lattice of thin-layered g-C 3 N 4 by a two-step thermal polymerization. S-g-C 3 N 4 /MoS 2 (SCN/MoS 2) heterojunctions were then created by a solvothermal synthesis. Subsequently, the electrochemical performance of the heterojunctions was explored. The result suggested that the surface of S-g-C 3 N 4 nanosheets load on uniformly arranged layered MoS 2 possession revealed the smallest Tafel slope of 77.2 mV dec−1. After 1000 cycles, no significant change was observed for the linear sweep voltammetry curves. The SCN/MoS 2 heterojunction revealed a specific capacity of 588 F g−1 after being assembled into an asymmetric supercapacitor. Superior thin g-C 3 N 4 nanosheets and constituting a composite with strong interfacial electronic coupling with MoS 2 , doping with heteroatomic elements, and changing the surface structure of g-C 3 N 4 enhanced the charge transfer kinetics and improved the electrochemical performance. • MoS 2 nanosheets were vertically grown on S-doped g-C 3 N 4 nanosheets to get enhanced electrochemical performance. • S in g-C 3 N 4 nanosheets plays an important role for the growth controlling of MoS 2 nanosheets. • S-g-C 3 N 4 /MoS 2 heterojunctions revealed the smallest Tafel slope and also revealed ideal energy storage performance. [ABSTRACT FROM AUTHOR]

The presence of harmful oxidizing gases accelerates the oxidation of cellulose fibers in paper, resulting in reduced strength and fading ink. Therefore, the development of highly sensitive NO2 gas sensors for monitoring and protecting books holds significant practical value. In this manuscript, ZnO/MoS2 composites were synthesized using sodium molybdate and thiourea as raw materials through a hydrothermal method. The morphology and microstructure were characterized by X-ray diffraction analysis (XRD), energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The ZnO/MoS2 composite exhibited a flower-like structure, with ZnO nanoparticles uniformly attached to the surface of MoS2, demonstrating advantages such as high specific surface area and good uniformity. The gas sensitivity of the ZnO/MoS2 nanocomposites reached its peak at 260 °C, with a sensitivity value around 3.5, which represents an improvement compared to pure ZnO, while also enhancing sensitivity. The resistance of the ZnO/MoS2 gas sensor remained relatively stable in air, exhibiting short response times during transitions between air and NO2 environments while consistently returning to a stable state. In addition to increasing adsorption capacity and improving light utilization efficiency, the formation of hetero-junctions at the ZnO-MoS2 interface creates an internal electric field that effectively promotes the rapid separation of photo-generated charge carriers within ZnO, thereby extending carrier lifetime. [ABSTRACT FROM AUTHOR]

Although polyaniline has a high electroactivity in environments below pH 5, it loses its electroactivity in neutral and basic environments. In addition, polyaniline film does not give physically stable film when it becomes thick. For these reasons, polyaniline has been synthesized in the presence of other monomers or inorganic/organic species, leading to the obtaining of composite polymers with some new electrochemical and physical properties. In this study, novel composite polymer films of polyaniline were synthesized electrochemically in the presence of different concentrations of Na2MoO4.2H2O and Na2WO4.2H2O, and these composite polymer films were examined in monomer-free solutions for electrochemical investigation. As a result, the cathodic charge of polyaniline increased from 0.25 mC to 1.50 mC in the presence of 0.05 M Na2MoO4.2H2O. Also, the polyaniline/WO3 composite achieved a charge transfer of 0.42 mC in the presence of 0.25 M NiSO4.2H2O, 0.05 M NiCl2.6H2O, Na2WO4, Na2MoO4.2H2O, 0.4 M Na3C6H5O7.2H2O and 0.05 Na2WO4.2H2O as a metal source. These prove the better charge transfer during the redox reaction of the polyaniline composite film. [ABSTRACT FROM AUTHOR]

Water scarcity, combined with low soil fertility, constitutes one of the main limiting factors in crop productivity in semi-arid regions. However, nutritional supplementation techniques with nitrogen (N) and molybdenum (Mo) can lead to positive enhancements in the production of these crops. The objective was to evaluate the effect of increasing doses of N in the presence and/or absence of Mo on the activity of antioxidant enzymes and the productive increase of forage sorghum subjected to water deficit in the semi-arid region. The experiment was conducted in the field using a randomized block design, with four replications, in a 5 × 2 × 3 factorial scheme, comprising five doses of N (urea): 0, 50, 100, 150, and 300 kg ha−1, two doses of Mo (sodium molybdate): 0 and 160 g ha−1, and three production cycles. The highest yields of green mass (GM) (47.98 Mg ha−1), dry mass (DM) (19.66 Mg ha−1), water use efficiency (WUE) (5.57 kg/m³), and N use efficiency (NUE) (0.26 kg2/g) occurred at the highest N dosage (300 kg ha−1 N). The highest contents and extraction of total N, Mo, chloride (Cl), and potassium (K) were found in regrowth 2 and at the highest N dose (300 kg ha−1). The interaction of N and Mo resulted in higher catalase (CAT) enzyme activity. The meteorological conditions during the cycles strongly influenced the nutrient contents and extraction. The results of the study provide support for producers to use N and Mo fertilization strategies to improve crop productivity, even under water deficit conditions. [ABSTRACT FROM AUTHOR]

The service performance of chromium-free zinc–aluminum coatings exhibits characteristics from multiple perspectives. Fully considering the physical properties, corrosion resistance, and economic viability of the coatings, this study incorporates the concepts of "domain" and "degree" from extenics theory into the analytic hierarchy process to optimize the formulation of chromium-free zinc–aluminum coatings. The findings reveal that the extension analytic hierarchy process takes into account the diversity of evaluation indicators, enhancing the objectivity and accuracy of the comprehensive evaluation results. Nine formulations were developed using a four-factor, three-level orthogonal experiment to evaluate the effects of metal powder, PEG-400, KH-560, and sodium molybdate on the service performance of chromium-free zinc–aluminum coatings. Utilizing an extensible hierarchical sorting weight system alongside a performance index grading and scoring method, 3# emerged with the highest score, indicating the best overall performance. The research outcomes offer innovative insights and technical support for optimizing the formulations of chromium-free zinc–aluminum coatings and other coatings. [ABSTRACT FROM AUTHOR]

Calcium molybdate (CaMoO4) is of significant interest due to its unique properties and numerous industrial applications, such as catalysis, electrochemistry, and optoelectronics. In this study, we developed an economical and environmentally friendly method to synthesize calcium molybdate from Moroccan phosphogypsum (PG) industrial waste and sodium molybdate, all at room temperature. Comprehensive analysis through X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman vibrational spectroscopy, and scanning electron microscopy (SEM) revealed the high purity of the synthesized calcium molybdate, with particle sizes of only 12 nm. Additionally, optical characteristics were studied using ultraviolet-visible spectroscopy (UV-vis), which showed an optical band gap of Egap = 3.96 eV for CaMoO4. These results confirm the successful synthesis of calcium molybdate nanoparticles from Moroccan phosphogypsum, demonstrating an effective pathway to valorize this industrial waste into a valuable material. This approach contributes to environmental sustainability by reducing dependence on rare chemicals while offering innovative solutions for the industry's sustainable development. [ABSTRACT FROM AUTHOR]

Most crops are fertilized with high amounts of nitrogen, and have an alarmingly low utilization efficiency. For this reason, the coordination between the fertilizer contribution and the nitrogen requirements of the crop is very important. Therefore, the objective of the present study was to establish new indices to determine nitrogen use efficiency (NUE), and to define the amount of assimilated nitrogen, which is used for the formation of green bean plant organs, fertilized with molybdenum nanofertilizer applied foliarly, and combined with edaphic fertilization of ammonium nitrate. The plants were grown in a greenhouse covered with anti-aphid mesh and irrigated with nutrient solution. Three sources of foliar molybdenum (Nanofertilizer, molybdenum Chelate and Sodium Molybdate) were applied in four doses of 0, 5, 10 and 20 ppm Mo, complemented with edaphic fertilization of NH4NO3 (0, 3, 6 and 12 mM of N). As results, the NUE indices showed that with the application of the nanofertilizer, the total biomass production increased 41.65% more than with the application of the chelate, and 36.84% more than with the application of molybdate. In summary, the dose that presented the highest efficiency was 6 mM-N with 10 ppm-Mo. Finally, it is concluded that the use of NUE indices is an important approach that evaluates the fate of nitrogen and accurately estimates plant yield. [ABSTRACT FROM AUTHOR]

In the present study, we are able to synthesize flakes of the 3R‐polytypes of MoS2 and WS2 from sodium molybdate and sodium tungstate in the presence of H2S gas by solid‐state reaction. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), and X‐ray diffraction are utilized to characterize the morphology, structure, and chemical composition of the 3R‐MoS2 and 3R‐WS2 flakes. The electrocatalytic and photocatalytic activities of 3R‐MoS2 and 3R‐WS2 flakes have been measured in hydrogen evolution reactions. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide(MoS2) has a special structure and excellent mechanical properties, making it a promising reinforcing filler for polymers. Carbon dots (CDs) have good antioxidant properties, and the addition of CDs during the synthesis of MoS2 can affect its morphology and size. In this work, a new one-step hydrothermal synthesis process was employed to prepare CDs/MoS2 hybrid particles. Thiourea, sodium molybdate, and glucose were employed as sources of sulfur, molybdenum, and carbon, respectively. The structure and morphology of MoS2 and CDs/MoS2 were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), mapping surface scanning (SEM–EDS), and Fourier transform infrared spectroscopy (FTIR). The results show that the prepared 2H-MoS2 is stacked into flower-like spheres with size around 2–10 μm; with the formation of CDs, the size of MoS2 rapidly decreases to less than 1 μm and the CDs are evenly distributed on its surface with mass ratio of 40.2% (CDs in CDs/MoS2). Subsequently, the CDs/MoS2 were used as reinforcing fillers for natural rubber (NR) latex. The results of mechanical properties show that tear strength, tensile strength, modulus, and elongation at break are increased by the addition of CDs/MoS2 in a very lower loading, and the maximum increment ratio is 45.6% and 12.1% when compared to NR-0; the dynamic mechanical analysis and cross-link density results indicated that the CDs/MoS2 can simultaneously improve rigidity and elasticity of NR. The thermal stability results suggest that the CDs/MoS2 shows positive effects on thermal stability of NR. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two-dimensional transition metal dichalcogenide heterostructures are potential candidates for next-generation semiconductor materials due to their extremely thin atomic structure and better optoelectronic properties. As a common method for growing heterostructures, chemical vapor deposition (CVD) can synthesize both lateral and vertical heterostructures. However, the controlled synthesis of heterostructures still faces challenges due to fewer studies about the evolution of heterostructure morphology under different conditions. In this study, heterostructures with sharp interfaces are fabricated via the vapor–liquid–solid (VLS) growth-based CVD technique using mixed sodium molybdate and sodium tungstate solutions. By optimizing a series of growth parameters, the modulation of MoxW1−xS2/MoS2 heterostructure morphology is achieved. In addition, lateral and vertical MoxW1−xS2/MoS2 heterostructures are synthesized by changing the molybdenum–tungsten molar ratio. This study provides a new strategy for synthesizing heterostructures with different growth ways. [ABSTRACT FROM AUTHOR]

Molybdenum (Mo) is a rare and important element extensively utilised in aerospace, radar communications, optoelectronic devices, and the military. This study proposes an environmentally friendly physical method based on photon–phonon resonance absorption for the separation of Mo from sodium molybdate (Na2MoO4). We examined the vibrational spectrum of Na2MoO4 using the CASTEP code, employing first-principles density functional theory. Through dynamic process analysis, we analysed the vibrational modes and assigned peaks corresponding to experimental infrared (IR) and Raman data. We focused on the vibrational modes associated with Mo and identified that the highest-intensity IR-active peak at 858 cm−1 corresponded to Mo–O bond asymmetric stretching. Therefore, we propose the use of a high-power terahertz laser at ~25 THz to facilitate the separation of Mo from Na2MoO4. Experimental investigations are expected in the future. [ABSTRACT FROM AUTHOR]

THIS study aimed to get a simple and reliable method to enhance the shelf life of compost tea. Freshly prepared compost tea was dispensed into transparent 1.5 L plastic bottles, enabling visual monitoring, with each bottle containing 1.3 L of compost tea. The treatments included T1 (3 mM sodium nitrate), T2 (6 mM sodium nitrate), T3 (0.2 mM sodium molybdate), T4 (0.4 mM sodium molybdate), and T5 (control without additives). The experiment was conducted in triplicate, and the bottles were stored in darkness at room temperature. Samples were withdrawn from each bottle at intervals of 2, 5, 10, 15, 25, and 30 days for analysis. At the end of the storage period, compost tea preparations underwent FT-IR analysis, revealing critical molecular features. A controlled pot experiment was conducted to evaluate the in vivo efficacy of the stored compost tea by assessing its impact on the growth and developmental progress of Corchorus Olitorius plants. Additionally, the enumeration of distinct microbial communities within the rhizosphere of the growing plants was performed. After 30 days, the most effective treatments compared to the control (T5) were T2 with increased bacterial Colony Forming Unit (CFU) (7.21) and Total Fungal colony (4.23), while T1 and T2 showed higher Azotobacter counts (4.95 and 5.00) respectively. However, T5 consistently displayed the lowest counts for Spore Formers Bacterial Unit (3.84). After extended storage, a control treatment exhibited new peaks at 1792 cm^-1 and 1175 cm^-1 suggested chemical changes, potentially carbonyl-containing compounds. These findings may have significant implications for sustainable agricultural practices and the utilization of compost tea as an environmentally friendly soil amendment. [ABSTRACT FROM AUTHOR]

Abstract Recycling of spent lead‐acid batteries (LABs) is extremely urgent in view of environmental protection and resources reuse. The current challenge is to reduce high consumption of chemical reagents. Herein, a closed‐loop spent LABs paste (SLBP) recovery strategy is demonstrated through Na2MoO4 consumption‐regeneration‐reuse. Experimental and DFT calculations verify that MoO42− competes Pb/Ca ions and weakens the metal‐oxygen bond of PbSO4/CaSO4.2H2O in SLBP, facilitating PbMoO4/CaMoO4 formation and 99.13 wt% of SO42− elimination. Pb of 99.97 wt% is obtained as zero‐carbon precursors (PbO2 and PbMoO4) by green leaching coupled with re‐crystallization. The regeneration of Na2MoO4 is realized at 600 ℃ using LABs polypropylene shells and NaOH as reagents. Compared with the traditional smelting technologies, the temperature is reduced from ＞1000 to 600 °C. The extraction of Na2MoO4 require only water, and satisfactory re‐used desulfurization efficiency (98.67 wt%) is achieved. For the residual Na2MoO4 after first SLBP desulfurization, the desulfurization efficiency remains above 97.36 wt% after adding fresh reagents for two running cycles. The new principle enables the reuse of 99.83 wt% of Na2MoO4 and the recycling of 95.27 wt% of Pb without generating wastewater and slags. The techno‐economic analysis indicates this strategy is efficient, economical, and environmentally‐friendly.

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]

A molybdenum‐catalyzed approach for intermolecular C−N coupling that produces aryl‐ and heteroaryl amines has been developed under microwave irradiation. The formation of C−N bonds with boronic acids and nitroaromatics using readily available catalysts remains a challenge. The method we developed employs a combination of readily available sodium molybdate dihydrate as a catalyst and tri‐n‐butyl phosphine as an inexpensive reductant to achieve reductive intermolecular coupling of nitroarenes with boronic acids. This approach has shown its versatility in facilitating the formation of Csp2−N bonds from aryl‐boronic acids as well as Csp3−N bonds from alkyl‐boronic acids. In addition, this reaction shows stereospecificity when Csp3−N bonds are formed. An array of boronic acids underwent C−N coupling with nitro arene providing the desired products in good yields [ABSTRACT FROM AUTHOR]

Mild steel corrosion is a significant challenge in oil and gas exploitation. Inhibitors are frequently employed to minimize the corrosive impact on mild steel. Mixing corrosion inhibitors is an effective method in reducing the dosage of toxic compounds and expanding the potential applications of inhibitors in NaCl solutions. Herein, a mixed corrosion inhibitor composed of imidazoline (IM), sodium molybdate, and sodium dodecylbenzenesulfonate (SDBS) for mild steel in a 3.5 wt% NaCl solution are investigated by orthogonal experimental design and electrochemical measurement. The imidazoline compound was synthesized and identified using Fourier transform infrared (FTIR) spectroscopy. The inhibitory effect is improved by higher concentrations of sodium molybdate and is further enhanced with the addition of 10 mg/L of SDBS. The electrochemical impedance spectroscopy indicates that the combination of IM (100 mg/L), sodium molybdate (50 mg/L), and SDBS (100 mg/L) results in excellent performance with electrochemical impedance (1.8 kohm·cm2). The mild steel surfaces after electrochemical measurement were analyzed using scanning electron microscopy (SEM). The information can contribute to the development of corrosion inhibitors with high performance or to understand the influence of mixing inhibitors on corrosion processes of mild steels. [ABSTRACT FROM AUTHOR]

In this study, dissimilar metal welding of A508/IN-182/IN-52M/308L/316L was employed in the fabrication of pipe nozzles for pressure vessels in pressurized water reactors (PWR). This process involved the fusion of lowalloy A508 and stainless steel 316L using gas tungsten arc welding (GTAW) welding, with the use of nickelbased alloy Inconel 182 as a filler material. Additionally, Inconel 52M served as an overlay layer, and material 308 acted as a buffer layer to facilitate bonding between 316L and the overlay welding layer. The primary objective of this study was to investigate the electrochemical aspects of galvanic corrosion and analyze the surface properties of dissimilar welds in a simulated PWR environment, specifically in a simulated hot water (SHW), over a three-month period. Potentiodynamic polarization tests were conducted on the testing solution, which contained a mixture of inhibitors, including sodium molybdate (Na2MoO4) and sodium nitrite (NaNO2). The surface morphology was thoroughly examined using optical microscopy and scanning electron microscopy - energy dispersive spectroscopy (SEM-EDS), while phase analysis was performed using x-ray diffraction (XRD) testing. The results indicated that the most efficient inhibitor combination treatment for dissimilar metal welds achieved an 89.98 % reduction in corrosion on A508 metal. This was accomplished by utilizing a mixed concentration of 6000 ppm sodium molybdates combined with 4000 ppm sodium nitrites. As a result, the corrosion rate of A508 decreased significantly from 0.475 mpy to 0.047 mpy, bringing it in line with the corrosion potential of other alloys and establishing a passive zone. In summary, the corrosion rate of A508/IN-182/IN-52M/ 308L/316L in PWR simulations decreased as the concentration of corrosion inhibitor, specifically sodium molybdate and sodium nitrite, increased. When the inhibitor dosage concentration was optimized, a protective thin molybdenum-containing film formed on the surface, effectively guarding against random pitting caused by galvanic corrosion. [ABSTRACT FROM AUTHOR]

The increasing use of molybdate has raised concerns about its potential toxicity in humans. However, the potential toxicity of molybdate under the current level of human exposure remains largely unknown. Endogenous metabolic alterations that are caused in humans by environmental exposure to pollutants are associated with the occurrence and progression of many diseases. This study exposed eight-week-old male C57 mice to sodium molybdate at doses relevant to humans (0.01 and 1 mg/kg/day) for eight weeks. Inductively coupled plasma mass spectrometry (ICP-MS) and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS) were utilized to assess changes in urine element levels and serum metabolites in mice, respectively. A total of 838 subjects from the NHANES 2017–2018 population database were also included in our study to verify the associations between molybdenum and cadmium found in mice. Analysis of the metabolome in mice revealed that four metabolites in blood serum exhibited significant changes, including 5-aminolevulinic acid, glycolic acid, l-acetylcarnitine, and 2,3-dihydroxypropyl octanoate. Analysis of the elementome revealed a significant increase in urine levels of cadmium after molybdate exposure in mice. Notably, molybdenum also showed a positive correlation with cadmium in humans from the NHANES database. Further analysis identified a positive correlation between cadmium and 2,3-dihydroxypropyl octanoate in mice. In conclusion, these findings suggest that molybdate exposure disrupted amino acid and lipid metabolism, which may be partially mediated by molybdate-altered cadmium levels. The integration of elementome and metabolome data provides sensitive information on molybdate-induced metabolic disorders and associated toxicities at levels relevant to human exposure. [ABSTRACT FROM AUTHOR]

From reactions involving sodium molybdate and dianilines [2,2′-(NH2)C6H4]2(CH2)n (n = 0, 1, 2) and amino-functionalized carboxylic acids 1,2-(NH2)(CO2H)C6H4 or 2-H2NC6H3-1,4-(CO2H)2, in the presence of Et3N and Me3SiCl, products adopting H-bonded networks have been characterized. In particular, the reaction of 2,2′-diaminobiphenyl, [2,2′-NH2(C6H4)]2, and 2-aminoterephthalic acid, H2NC6H3-1,4-(CO2H)2, led to the isolation of [(MoCl3[2,2′-N(C6H4)]2}{HNC6H3-1-(CO2),4-(CO2H)]·2[2,2′-NH2(C6H4)]2·3.5MeCN (1·3.5MeCN), which contains intra-molecular N–H∙∙∙Cl H-bonds and slipped π∙∙∙π interactions. Similar use of 2,2′-methylenedianiline, [2,2′-(NH2)C6H4]2CH2, in combination with 2-aminoterephthalic acid led to the isolation of [MoCl2(O2CC6H3NHCO2SiMe3)(NC6H4CH2C6H4NH2)]·3MeCN (2·3MeCN). Complex 2 contains extensive H-bonds between pairs of centrosymmetrically-related molecules. In the case of 2,2′ethylenedianiline, [2,2′-(NH2)C6H4]2CH2CH2, and anthranilic acid, 1,2-(NH2)(CO2H)C6H4, reaction with Na2MoO4 in the presence of Et3N and Me3SiCl in refluxing 1,2-dimethoxyethane afforded the complex [MoCl3{1,2-(NH)(CO2)C6H4}{NC6H4CH2CH2C6H4NH3}]·MeCN (3·MeCN). In 3, there are intra-molecular bifurcated H-bonds between NH3 H atoms and chlorides, whilst pairs of molecules H-bond further via the NH3 groups to the non-coordinated carboxylate oxygen, resulting in H-bonded chains. Complexes 1 to 3 have been screened for the ring opening polymerization (ROP) of both ε-caprolactone (ε-CL) and δ-valerolactone (δ-VL) using solvent-free conditions under N2 and air. The products were of moderate to high molecular weight, with wide Ð values, and comprised several types of polymer families, including OH-terminated, OBn-terminated (for PCL only), and cyclic polymers. The results of metal-free ROP using the dianilines [2,2′-(NH2)C6H4]2(CH2)n (n = 0, 1, 2) and the amino-functionalized carboxylic acids 1,2-(NH2)(CO2H)C6H4 or 2-H2NC6H3-1,4-(CO2H)2 under similar conditions (no BnOH) are also reported. The dianilines were found to be capable of the ROP of δ-VL (but not ε-CL), whilst anthranilic acid outperformed 2-aminoterephthalic acid for both ε-Cl and δ-VL. [ABSTRACT FROM AUTHOR]

Nitrate accumulation is a common problem in most leafy vegetables and it happens when the amount of nitrate absorption exceeds the amount consumed by the plant. This study was conducted as a factorial experiment in the form of a completely randomized design and in three replications. The first factor included adding nitrate (calcium nitrate) to Hoagland's standard solution at three levels of 0, 10 and 20%, and the second factor was adding different concentrations of molybdenum from sodium molybdate salt at four levels of 0, 0.5, 1.5 and 3 µM. The measured traits included traits of some growth characteristics, total phenol and flavonoids, ascorbic acid, spinach leaf nitrate. According to the obtained results, fresh and dry weight of leaf, dry weight of root and percentage of dry matter increased by increasing calcium nitrate concentration up to 20% and molybdenum application up to 3 µM in nutrient solution. The simultaneous application of molybdenum and nitrogen had no significant effect on total phenolic, total flavonoid and ascorbic acid traits, and the highest amount of these traits was observed in 3 µM molybdenum. The highest amount of leaf nitrate (3247.4 mg kg-1 FW) was observed in the treatment of 20% additional nitrate along with molybdenum. Based on the results, the use of molybdenum in nutrient solution had a reducing effect on nitrate accumulation in spinach leaf, therefore adding 3 µM sodium molybdate to Hoagland nutrient solution in hydroponic system for spinach production is recommended to obtain the maximum amount of antioxidant compounds and the minimum amount of nitrate accumulation. Introduction Plants take nitrogen (N) either as nitrate (NO3-) or ammonium (NH4+) form for various growth and developmental processes; however, NO3- is more important for such processes. For most of the crop plants, the nitrate form is mobile, less toxic, and can be stored in vacuoles. However, Nitrate must be reduced to NH4+ before it can be utilized for the synthesis of amino acids, proteins, and other nitrogenous compounds in plant cells. Nitrate reductase (NR) and nitrite reductase (NiR), the key nitrate assimilatory enzymes, are located in cytosol and chloroplasts and catalyze nitrate reduction to NO2- followed by NO2- to NH4+, respectively, in the leaf tissues. However, NH4+ is directly assimilated to produce different amino acids by the mutual actions of glutamine synthetase (GS) and glutamate synthase (GOGAT) enzymes in a cyclic manner within the plant cells. Nitrate accumulation is a common problem in most leafy vegetables and it happens when the amount of nitrate absorption exceeds the amount consumed by the plant. Molybdenum (Mo) is an essential microelement for higher plants and also a metal component of the Mo-cofactor, (Moco) biosynthesis. Moco binds to Mo-requiring enzymes and optimizes their activities for normal functioning of plant growth and developmental processes. Molybdenum plays a significant role in N metabolism, which includes nitrate reduction, assimilation, and fixation, by regulating the NR and GS enzymes activities and expressions. During symbiotic N fixation, Mo acts as a cofactor for nitrogenase enzymes to catalyze the redox reaction to convert elemental N into ammonium ions. Materials and methods This study was conducted as a factorial experiment in the form of a completely randomized design and in three replications. The first factor included adding nitrate (calcium nitrate) to Hoagland's standard solution at three levels of 0, 10 and 20%, and the second factor was adding different concentrations of molybdenum from sodium molybdate salt at four levels of 0, 0.5, 1.5 and 3 µM. This research was conducted in the research greenhouse of Campus of Agriculture and Natural Resources Razi University. Senator spinach seeds were obtained from Fardin Kasht Alborz Institute. Spinach seeds were disinfected with 1% sodium hypochlorite for 5 minutes and then planted in seedling trays containing cocopeat and perlite with a volume ratio of 1:1. The measured traits included traits of some growth characteristics, total phenol and flavonoids, ascorbic acid, spinach leaf nitrate. Results and discussion According to the obtained results, fresh and dry weight of leaf, dry weight of root and percentage of dry matter increased by increasing calcium nitrate concentration up to 20% and molybdenum application up to 3 µM in nutrient solution. The simultaneous application of molybdenum and nitrogen had no significant effect on total phenolic, total flavonoid and ascorbic acid traits, and the highest amount of these traits was observed in 3 µM molybdenum. The highest amount of leaf nitrate (3247.4 mg kg-1 FW) was observed in the treatment of 20% additional nitrate along with molybdenum. The most important point in this research was the use of molybdenum to control nitrate accumulation, and the use of molybdenum in concentrations of 1.5 and 3 µM was able to reduce the amount of nitrate accumulation in the aerial parts to some extent, thus neutralizing the toxicity of excess nitrate. The use of sodium molybdate can be one of the recommended ways to reduce the accumulation of nitrates and at the same time enrich molybdenum in spinach and increase the nutritional value of this plant. Conclusion Nitrate and ammonium are the major forms of N that plants use for different growth and developmental processes. The present study revealed that Mo fertilizer plays a key role in N metabolism through regulating the activities and expressions of N-assimilating enzymes. In general, the results of this research showed that the increase in molybdenum concentration in hydroponic culture affected the growth and biochemical characteristics of spinach. Based on the results, the use of molybdenum in nutrient solution had a reducing effect on nitrate accumulation in spinach leaf, therefore adding 3 µM sodium molybdate to Hoagland nutrient solution in hydroponic system for spinach production is recommended to obtain the maximum amount of antioxidant compounds and the minimum amount of nitrate accumulation. [ABSTRACT FROM AUTHOR]

Ag2MoO4 crystals were prepared by a precipitation method by mixing parent solutions of silver nitrate and sodium molybdate. The effects of experimental parameters such as temperature, concentration, and pH were studied. The samples were found to be crystalline, pure, and monophasic in all cases, except in the case of very low pH. The precipitation leads to the formation of the cubic phase β and no secondary phase is present within the limits of detection of XRD and Raman spectroscopy. However, in some cases, at high temperature and high pH, silver oxide nanoparticles form on the surfaces of the crystals, which create a fluorescence background in the Raman spectra, which is otherwise absent. Analyses with the electron microscope have highlighted that the most common crystalline shape is octahedral, which is the most prevalent at low temperatures and pH around 7, but others are also possible, in particular at high temperatures. No growth occurs after precipitation, so crystals with different appearances form at the same time. [ABSTRACT FROM AUTHOR]

The circular saw blade, which is mainly composed of carbon steel, is used to cut the stone. However, the carbon steel is easily corroded in stone processing wastewater, shortening its lifespan. In this study, a new composite inhibitor of sodium nitrite, sodium molybdate, sodium silicate, sodium tungstate, and sodium citrate was investigated firstly, and then, its inhibition efficiency for carbon steel in stone processing wastewater was explored using electrochemical measurements and weight loss measurements. The results showed that the composite inhibitor as a mixed‐type inhibitor displayed good inhibitory performance. Surface analysis including scanning electron microscope, atomic force microscope, X‐ray photoelectron spectroscopy analysis, and contact angle test further revealed the form of protection of the steel surface by composite corrosion inhibitors. The prepared composite inhibitor exhibited excellent corrosion resistance for carbon steel in stone processing wastewater, and it is believed that the composite inhibitor has certain application potential in industries. [ABSTRACT FROM AUTHOR]

This study analyzes the corrosion inhibition efficiency of sodium molybdate (SM) solution on weldment specimens in 1 M HCl, based on H2 bubbles detection. The detection of the bubbles produced by the corrosion process is achieved by a YOLOv4 deep learning algorithm. The results indicate that the corrosion rate is higher on the weld metal zone than on the base metal zone in the same solution, which might be attributed to the coarser grain of the weld metal zone and the stability of the produced oxide layer. The addition of sodium molybdate was discovered to boost the stability of the oxide layer, hence enhancing the specimens' corrosion resistance. The overall inhibitory efficiency of the sodium molybdate solution was 59% for the weld metal (WM) (0.4 g/L), 52% for the heat-affected zone (HAZ) (0.2 g/L), and 37% for the base metal (BM) (0.2 g/L). The object detection algorithm models showed 97% for the mAP and 0.98 for recall. The minimum average bubble detected for the WM was 0.353 /mm2 at an SM concentration of 0.4 g/L, while the HAZ was 0.612 /mm2 at 0.2 g/L, and the BM was 1.055 /mm2 at 0.2 g/L. The results of the bubbles detection appeared to be consistent with the corrosion experiment outcomes obtained by the potentiodynamic polarization and hydrogen volume measurement tests. This experiment validates the distinctiveness of the different weld zones in terms of the inhibitor concentration required for successful corrosion prevention, as well as the potential of analyzing corrosion using machine learning algorithms for object detection. [ABSTRACT FROM AUTHOR]

Carbonized silk paves the way for the design and construction of wearable electronics. The composition of silk fibers can be modulated by feeding silkworms with specific diets, which can enhance the functionality of the carbonized silk. In our previous work, the silkworms were fed ammonium molybdate tetrahydrate solution sprayed mulberry leaves to obtain carbonized silk fibers (CSF) possessing a maximum specific capacitance of 298 F/g at 0.2 A/g. In this work, we fed the silkworms sodium molybdate solution sprayed mulberry leaves, for which silkworms present a high tolerance, in order to raise the quantity of the element Mo incorporated within the silk. Transmission electron microscopy - energy dispersive X-ray spectroscopy was utilized to observe and analyze grains, grown through the process of carbonization, inside the carbonized silk. It was confirmed that the composition of those grains are MoO2. Electrochemical measurements show these CSF based electrodes possess outstanding capacitance behavior with a specific capacitance of 524 F/g at 0.2 A/g. Additionally, the electrodes show excellent cyclability. The capacitance retention ratio can reach up to 96.84% after 5000 galvanostatic charge/discharge cycles at 0.2 A/g. Our strategy is straightforward and does not require any hazardous or organic solvents, therefore is an illustration of a green procedure for functionalized CSF synthesis. Furthermore, because the precursor fed to silkworm is water soluble and can be easily dispersed over the surface of mulberry leaves, the method described is suitable for bulk and large scale production of functionalized CSF.

Molybdenum (Mo) is a rare and important element extensively utilised in aerospace, radar communications, optoelectronic devices, and the military. This study proposes an environmentally friendly physical method based on photon–phonon resonance absorption for the separation of Mo from sodium molybdate (Na2MoO4). We examined the vibrational spectrum of Na2MoO4 using the CASTEP code, employing first-principles density functional theory. Through dynamic process analysis, we analysed the vibrational modes and assigned peaks corresponding to experimental infrared (IR) and Raman data. We focused on the vibrational modes associated with Mo and identified that the highest-intensity IR-active peak at 858 cm−1 corresponded to Mo–O bond asymmetric stretching. Therefore, we propose the use of a high-power terahertz laser at ~25 THz to facilitate the separation of Mo from Na2MoO4. Experimental investigations are expected in the future.

Development of the technologies for energy storage and conversion requires a search for compounds with high diffusion of alkali and alkaline-earth ions. Here, we present the results of comprehensive studies, including synthesis, powder X-ray diffraction, experiments on impedance and 23Na NMR spectroscopy, as well as ab initio calculations, which were carried out to explore the sodium diffusion in scheelite-like Na 5 M (MoO 4) 4 with M = Y, La, Bi, and in related solid solutions Na 5- x M 1- x Zr x (MoO 4) 4 (0.05 ≤ x ≤ 0.1), which were synthesized for the first time. Our investigations reveal that the Na-ion mobility increases in the sequence Y → La → Bi and with growing x. For Na 4.9 Bi 0.9 Zr 0.1 (MoO 4) 4 the highest ion conductivity was found: ∼10−4 S/cm at T = 450 °C, which is comparable to that of the NASICON-type molybdates. From the temperature variations of the 23Na NMR spectra and DFT calculations, the mechanism of sodium-ion diffusion was established at the atomic-scale level. [ABSTRACT FROM AUTHOR]

The requirement for molybdenum (Mo) for legume and pasture growth on New Zealand soils was first identified in the 1950s and most of the research was carried out up to the 1980s. This resulted in a recommendation to apply 56–70 g/ha of sodium molybdate every 4–5 years that was later modified to 50 g/ha every five years. On most soils, the availability of Mo increased with soil pH but the rates of lime required were uneconomic on hill country pastures so Mo was applied as the most cost-effective option. Measuring available soil Mo was a poor predictor of pasture yield responses to Mo compared with the Mo content of clover. More recent research showed that the Mo content of clover had to be less than 0.1 ppm and nitrogen (N) content less than about 4.5% for a definite response in yield to applied Mo to occur. High natural levels of soil Mo elevating pasture Mo content above 0.5–1 ppm or overuse of fertiliser Mo where pasture copper (Cu) is low (<5 ppm for sheep, <10 ppm for cattle and deer) can cause less Cu to be adsorbed from the rumen and reduce animal growth. [ABSTRACT FROM AUTHOR]

Ni-Mo-ZrO2 composite coatings with a thickness ranging from 6.9 to 8.7 µm were obtained by direct-current electrodeposition from a bath comprising nickel sulfate and sodium molybdate as main salts, and ZrO2 nanoparticles as ceramic phase. The effect of mass concentration of ZrO2 on the microstructure, mechanical properties, and corrosion resistance of Ni-Mo-ZrO2 composite coating was studied. The results showed that the mass fraction of ZrO2 in composite coating was increased with the increasing of mass concentration of ZrO2 in bath, while the surface morphology, wear resistance, and corrosion resistance got better initially and then worse, and the nanohardness was increased at first and then decreased. The composite coating electrodeposited with 10 g/L of ZrO2 exhibited the best corrosion resistance, while the one electrodeposited with 20 g/L of ZrO2 featured the best microstructure and mechanical properties. [ABSTRACT FROM AUTHOR]

A field experiment was undertaken in the post-Rabi season of 2019-2020 to reveal the response of greengram (Vigna radiata L.) to seed dressing and seed priming with nano molybdenum trioxide (MoO3). The experiment was laid out in randomized block design (RBD) consisting of 10 different treatments i.e., M0 (no seed treatment with Mo); M1 (seed dressing with Sodium molybdate @ 400 ppm); M2, M3, M4, and M5 (seed dressing with nano Molybdenum trioxide-MoO3 @ 50, 100, 200 and 400 ppm, respectively); and M6, M7, M8 and M9 (seed priming with nano MoO3 @ 50, 100, 200 and 400 ppm, respectively). Inoculation of greengram seeds cv. Shreya (IPM 2-14) with Rhizobium sps. was undertaken in all treatments as per the recommended practice, except in M0 (control). The MoO3 nanoparticles (NPs) synthesized from Ammonium molybdate through calcination at 600 0C for 5 hours indicated globular-shaped NPs of 68.55 nm in TEM and XRD. Nanopriming with MoO3 @ 200 ppm (M8) was most promising in recording significantly superior growth and yield attributing parameters and yield, whereas Mo (control) produced the least. Crop height, number of branches, root length, shoot dry matter, pods/plant and seeds/plant and root nodulation at harvest in M8 were 39.4% and 22.6%; 39% and 5.6%; 23% and 9.3%; 43.9%, and 16.3%; 28.2% and 5.3%; 28.1% and 0.8%, and 73.3% and 36.5% higher than M0 (control) and M1 (farmers' practice), respectively. Superior growth and yield attributing characters in M8 treatment produced the highest grain and stover yield of 0.88 and 3.74 t/ ha that was 32.53% and 8.37%, and 35.5% and 14.7% higher than M0 (control) and M1 (farmers' practice), respectively. Seed priming with nano MoO3 @ 400 ppm (M9) and seed dressing with nano MoO3 @ 400 ppm (M5) were of second and third order in recording grain and stover yield but M0 recorded the lowest among all the treatments. [ABSTRACT FROM AUTHOR]

This paper evaluates crystallographic data and thermodynamic properties for sodium chromate, potassium chromate, sodium molybdate, potassium molybdate (K2MoO4), sodium tungstate, and potassium tungstate collected from the literature. A thorough literature review was carried out to obtain a good understanding of the available data, and a critical evaluation has been performed from room temperature to above the melting temperatures. Also, the solid–solid transition and melting properties of the six pure salts were measured by differential scanning calorimetry, and high-temperature x-ray powder diffraction measurements were performed to determine the crystal structures and space groups associated with the phases of K2MoO4. This work is the first step towards the development of a thermodynamic model for the Na+, K+//Cl−, SO42−, CO32−, CrO42−, Cr2O72−, MoO42−, Mo2O72−, WO42−, W2O72−, O2− system that is relevant for high temperature corrosion in atmospheres containing O–H–S–C–Cl and alkali salts. [ABSTRACT FROM AUTHOR]

A supramolecular compound composed of reduced phosphopolybdate and FeII was synthesized by hydrothermal method with sodium molybdate, ferric nitrate, phosphoric acid and triethylenetetramine as raw materials. The chemical formula of the compound is [C8H24N4]1.5 [C6H22N4]1.5 {Fe[Mo6O12 (OH)3 (PO4)3 (HPO4)]2}·5H2O (1). Single crystal X-ray diffraction, powder X-ray diffraction (PXRD) and infrared spectroscopy (FT-IR) characterizations show that compound 1 is composed of {FeP4Mo6VO31]222- (denoted by {Fe(P4Mo6)2}), protomated triethyltetramine and protomated N, N'- bis(aminoethyl)-piperazine in a three-dimensional supramolecular structure through hydrogen bond interactions. The results of electrocatalytic performance measurement show that compound 1 has good electrochemical sensing performance and low limit of detection (LOD) for chromium ion (CrVI), iron ion (FeIII), potassium bromate (KBrO3) and ascorbic acid (AA). [ABSTRACT FROM AUTHOR]

Cowpea is a legume rich in amino acids and proteins, cultivated worldwide. However, the crop has low grain yield, which is attributed to inadequate management of fertilizers. Therefore research was conducted to evaluate the effect of phosphorus applied via soil and molybdenum via leaves on productivity and seed molybdenum concentration of cowpea. The experiment was carried out in a greenhouse, in a 4 x 4 factorial scheme: Molybdenum doses (Mo) (0, 100, 250 or 500 g ha−1 of sodium molybdate) and doses of phosphorus (0, 50, 100 or 150 kg P2O5 ha−1), in a randomized block design, with four replications. Mo applications were split in the flowering and maturation phase to ensure the best absorption of micronutrients. At the end of maturation, pod length, pod mass, number of grains per pod, 100 grain mass, grain yield, seed molybdenum and concentration were measured. There was a significant interaction between the doses of phosphorus and molybdenum for pod length and number of grains per pod with increments in production and optimal dose estimated at 374.15 g ha−1 of molybdenum and 123.43 kg ha−1 of phosphorus. Phosphate fertilization increases grain yield, pod dry weight and 100-grain weight by 41%, 51% and 20%, respectively, compared to the control treatment. The splitting of molybic fertilization is an effective way to increase the nutrient concentration in the seed, which leads to a reduction in the cost of producing Mo-rich seeds, without causing toxic effects on plants. [ABSTRACT FROM AUTHOR]

Soybean is a leguminous crop known for its efficient nitrogen utilization and ease of cultivation. However, its intercropping with maize may lead to severe reduction in its growth and yield due to shading effect of maize. This issue can be resolved by the appropriate application of essential plant nutrient such as molybdenum (Mo). Aim of this study was to assess the effect of Mo application on the morphological and physiological characteristics of soybean intercropped with maize. A two-year field experiment was conducted for this purpose, and Mo was applied in the form of sodium molybdate (Na2MoO4), and four different levels were maintained i.e., 0, 60, 120 and 180 g ha-1. Soybean exhibited varying responses to different levels of molybdenum (Mo) application. Notably, in both sole and intercropped cropping systems, the application of Mo at a rate of 120 g ha-1 demonstrated the highest level of promise compared to other application levels. However, most significant outcomes were pragmatic in soybean-maize intercropping, as application of Mo @ 120 g ha-1 significantly improved soybean growth and yield attributes, including leaf area index (LAI; 434 and 441%), total plant biomass (430 and 461%), transpiration rate (15 and 18%), stomatal conductance (9 and 11%), and yield (15 and 20%) during year 2020 and 2021 respectively, as compared to control treatment. Similarly, Mo @ 120 g ha-1 application resulted in highest total grain yield (626.0 and 725.3 kg ha-1) during 2020 and 2021 respectively, which exceeded the grain yields of other Mo levels under intercropping. Moreover, under Mo application level (120 g ha-1), grain NPK and Mo contents during years 2020 and 2021 were found to be 1.15, 0.22, 0.83 and 68.94 mg kg-1, and 1.27, 0.25, 0.90 and 72.18 mg kg-1 under intercropping system increased the value as compared to control treatment. Findings of current study highlighted the significance of Mo in enhancing soybean growth, yield, and nutrient uptake efficiency in maize-soybean intercropping systems. [ABSTRACT FROM AUTHOR]

To fulfill the demands of more bandwidth in 5G and 6G communication technology, new dielectric substrates that can be co‐fired into packages and devices that have low dielectric loss and improved thermal conductivity are desired. The motivation for this study is to design composites with low dielectric loss (tan δ) and high thermal conductivity (κ), while still limiting the electrical conductivity, for microwave applications involving high power and high frequency. This work describes the fabrication of high‐density electroceramic composites with a model dielectric material for cold sintering, namely sodium molybdate (Na2Mo2O7), and fillers with higher thermal conductivity such as hexagonal boron nitride. The physical properties of the composites were characterized as a function of filler vol.%, temperature, and frequency. Understanding the variation in measured properties is achieved through analyzing the respective transport mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, nucleation parameters such as induction period, interfacial tension, metastable zone width, radius of critical nucleus and Gibbs free energy change in solutiongrown triglycine sodium molybdate (TGSM) single crystals are studied. The solubility of TGSM at different temperatures has been determined. The induction period and metastable zone width have been experimentally found for optimizing the growth process. Various critical nucleation parameters have been calculated from the experimentally obtained values based on the classical nucleation theory. The nucleation rate is found to increase with the growth of the supersaturation value. The third order non-linear parameters such as absorption coefficient (β), susceptibility (χ (3)) and refractive index (n2) obtained from the Z-scan analysis confirm the self focusing and reverse saturation absorption nature of the grown crystals. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article describes the technology of molybdic acid recovery from spent petrochemical catalysts (HDS) developed and implemented in industrial activity. HDS catalysts contain molybdenum in the form of MoO3 and are used for the hydrodesulfurization of petroleum products. After deactivation, due to the impurities content in the form of sulfur, carbon and heavy metals, they constitute hazardous waste and, at the same time, a valuable source of the Mo element, recognized as a critical raw material. The presented technology allows the recovery of molybdic acid with a yield of min. 81%, and the product contains min. 95% H2MoO4. The technology consisted of oxidizing roasting of the spent catalyst, then leaching molybdenum trioxide with aqueous NaOH to produce water-soluble sodium molybdate (Na2MoO4), and finally precipitation of molybdenum using aqueous HCl, as molybdic acid (H2MoO4). Industrial-scale testing proved that the technology could recover Mo from the catalyst and convert it into marketable molybdic acid. This proves that the technology can be effectively used to preserve molybdenum. [ABSTRACT FROM AUTHOR]

The energies of intrinsic defects in sodium-gadolinium molybdate crystals are estimated by atomistic modeling. It is established that sodium Frenkel defects have the lowest formation energies and are the most probable type of intrinsic defects in sodium-gadolinium molybdates. The Schottky defects and particularly the molybdenum Frenkel defects, containing molybdenum vacancies, require much higher formation energies and are therefore less probable. In general, the energy of defect formation in the NaGd(MoO4)2 crystal, characterized by disordered distribution of sodium and gadolinium ions with different valences, is lower than in its structural analogue CaMoO4. [ABSTRACT FROM AUTHOR]

Hydrothermal synthesis technique was employed to synthesize molybdenum diselenide (MoSe2) nanoflowers from three different molybdenum precursors including sodium molybdate, ammonium molybdate and molybdenum trioxide. The hydrothermal reaction of one of the precursor of molybdenum and selenium powder took place in an autoclave at 210 °C for 48 h. The reaction temperature, molar ratio of precursors and reaction time were fixed in all three reactions. The as obtained powder was characterized using various characterization techniques before further processing. Successful synthesis of MoSe2 nanoflowers was confirmed through FESEM analysis after which the powder was further processed to synthesize MoSe2 quantum dots (QDs). Additionally, thin films of all the materials were synthesized under the same conditions, and a two-terminal device setup was used to analyze their transport characteristics. Electrical conductivity, carrier concentration, and mobility of all the samples were determined using Hall measurements and current–voltage characteristics in the 30–70 °C temperature range. The sample made with sodium molybdate was found to have the least amount of leakage current, making it suitable for use in high power and high voltage applications. Although the other two samples had moderate to high leakage currents, they were more conductive than the sodium molybdate sample, allowing them to be used in situations where leakage current could be limited or controlled by outside sources. The outcomes show that the electrical characteristics of MoSe2 are significantly influenced by the molybdenum precursors used. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present work, the new aluminium-substituted polyoxometalates of the Anderson-Evans type have been prepared and structurally defined by the reaction of aluminium (III) chloride hexahydrate and sodium tungstate dihydrate/sodium molybdate dihydrate in an aqueous basic medium. Elemental analysis, FT-IR, TGA, ¹H NMR, and 31P NMR analysis revealed that these polyoxometalates had the following formula: [Ph4P]3[Al(OH)6Mo6O18]·4H2O 1, [Ph4P]3[Al(OH)6W6O18]·4H2O 2, [C7H10N]3[Al(OH)6Mo6O18]·4H2O 3, [C7H10N]3[Al(OH)6W6O18]·4H2O 4. The compounds 1 and 2 show promising antibacterial activity against gram-positive Staphylcoccus aureus ATCC 25923 and gram-negative Escherichia coli ATCC 25922 bacteria. [ABSTRACT FROM AUTHOR]

Uric acid shows good quality sensitivity with sodium molybdate and methyl red personalized glassy carbon electrode. In this amend sodium molybdate was ionically deposited resting on the surface of the working electrode of the glassy carbon electrode, and then the facade of the electrode was electropolymerized with methyl red. The electropolymerization of methyl red on the working electrode was done by potential cycling in 0.2M phosphate buffer solution at pH 5.0 to 8.0. Very sensitive peak potentials of uric acid pragmatic in the presence of two made-to-order materials. This sensitivity nature was precisely investigated at physiological pH of 7.4, the rate of scan consequence tells regarding circulation inhibited electrode assets and concentration effect gives for uric acid good limit of detection that is 3.020 x 10-5 M calculated at the modified electrode. The complete study explains the oxidation mechanism of uric acid concerning an identical number of electrons and protons on the surface of the Sodium Molybdate/Poly (Methyl Red) modified glassy carbon electrode with elevated sensitivity. [ABSTRACT FROM AUTHOR]

The paper analyzes the relationships among acid–base interactions in various oxide systems and their thermodynamics. Extensive data on enthalpies of solution of binary oxides in oxide melts of several compositions, obtained by high-temperature oxide melt solution calorimetry at 700 and 800 °C, are systematized and analyzed. Oxides with low electronegativity, namely the alkali and alkaline earth oxides, which are strong oxide ion donors, show enthalpies of solution that have negative values greater than −100 kJ per mole of oxide ion. Their enthalpies of solution become more negative with decreasing electronegativity in the order Li, Na, K and Mg, Ca, Sr, Ba in both of the commonly used molten oxide calorimetric solvents: sodium molybdate and lead borate. Oxides with high electronegativity, including P2O5, SiO2, GeO2, and other acidic oxides, dissolve more exothermically in the less acidic solvent (lead borate). The remaining oxides, with intermediate electronegativity (amphoteric oxides) have enthalpies of solution of between +50 and −100 kJ/mol, with many close to zero. More limited data for the enthalpies of solution of oxides in multicomponent aluminosilicate melts at higher temperature are also discussed. Overall, the ionic model combined with the Lux–Flood description of acid–base reactions provide a consistent and useful interpretation of the data and their application for understanding the thermodynamic stability of ternary oxide systems in solid and liquid states. [ABSTRACT FROM AUTHOR]

In the present study, the effects of soil-applied different molybdenum concentrations (0.1, 0.5, 2.5, 12.5 or 62.5 mg kg−1) in the form of sodium molybdate on growth performance, seed production, biochemical parameters, and uptake of Mo in wheat were investigated. Results indicate that Mo doses higher than 2.5 mg kg−1 of soil were observed to be toxic to wheat and retarded the growth as well as seed production. The change in biochemical constituents were correlated with soil Mo concentrations. Chlorophyll and carbohydrate contents increased under lower concentrations of Mo applied. In turn, Mo concentrations beyond 2.5 mg kg−1 significantly increased soluble proteins, total phenolic compounds, and free proline contents. The contents of Mo in root and shoot of wheat plants increased with increased Mo concentrations in the soil. Among the various concentrations of Mo studied, 2.5 mg kg−1 was moderately toxic while 12.5 and 62.5 mg kg−1 were highly toxic and induced stress responses to confer tolerance in wheat. [ABSTRACT FROM AUTHOR]

Recently, much research has investigated nanocomposites and their properties for the development of energy storage systems. Supercapacitor performance is usually enhanced by the use of porous electrode structures, which produce a larger surface area for reaction. In this work, a biocompatible polymer of starch medium was used to create the porous nanostructure. Two powders, i.e., Nickel molybdate/reduced graphene oxide (NiMoO4-rGO) and Nickel molybdate/nitrogen-doped reduced graphene oxide (NiMoO4-NrGO), were synthesized using the deposition method in a medium containing starch, nickel nitrate salts, sodium molybdate, and graphene oxide powder. In terms of electrochemical performance, the NiMoO4-NrGO electrode displayed a higher specific capacitance, i.e., 932 Fg−1 (466 Cg−1), than the NiMoO4-rGO electrode, i.e., 884 Fg−1 (442 Cg−1), at a current density of 1 Ag−1. In fact, graphene oxide sheets could lose more oxygen groups in the presence of ammonia, resulting in increased electrical conductivity. For the asymmetric supercapacitor of NiMoO4-NrGO//AC, the specific capacitance at 1 Ag−1, energy density, and power density were 101.2 Fg−1 (111.32 Cg−1), 17 Wh kg−1, and 174.4 kW kg−1, respectively. In addition, this supercapacitor material displayed a good cycling stability of over 82%. [ABSTRACT FROM AUTHOR]