Search Results (325)

The Galale Cu–Au deposit lies on the northern margin of the western Gangdese metallogenic belt, near the western edge of the Gangdese arc within the Bangong–Nujiang suture zone. Unlike the well-studied Miocene Cu belt in southern Gangdese, this region remains insufficiently investigated, particularly in terms of geochemical characterization, leading to an ambiguous metallogenic model and a debated tectonic setting—specifically, the unresolved issue of subduction polarity across the Bangong–Nujiang suture. This tectonic ambiguity has important implications for understanding magma sources, metal transport pathways, and, consequently, for guiding mineral exploration strategies in the area. To address this, we conducted zircon U–Pb dating on the ore-related quartz diorite and granodiorite, yielding crystallization ages of 84.05 ± 0.34 Ma and 77.20 ± 0.69 Ma, respectively. Integrated with previous data, these results constrain mineralization to 83–89 Ma, which includes both skarn-type Cu–polymetallic and porphyry-type Cu mineralization. Regional comparisons support a tectonic model involving slab rollback and southward subduction of the Bangong–Nujiang oceanic lithosphere. Geochemical analyses of quartz diorite, granodiorite, and monzonitic granite show high-K calc-alkaline, peraluminous I-type affinities, with enrichment in LREEs and LILEs, and depletion in HREEs and HFSEs. Notably, the monzonitic granite is marked by high SiO₂, Sr/Y, and Rb/Sr ratios, low Zr/Hf, strong LREE enrichment, weak Eu anomalies, and pronounced Nb–Ta depletion, indicating high oxygen fugacity and favorable conditions for Mo mineralization. The deposit formed through tectono-magmatic processes related to the closure of the Bangong–Nujiang Neo-Tethys Ocean. Subduction and subsequent lithospheric delamination induced partial melting of mantle and crustal sources, generating quartz diorite and granodiorite intrusions. Magmatic fluids interacted with carbonate wall rocks to form skarn assemblages, concentrating ore metals along structures. The mineralization formed within the contact zones between intrusions and surrounding country rocks. Late-stage granite porphyry intrusions (~77 Ma), inferred from major, trace, and rare earth element compositions to have the highest Mo potential, may represent an extension of earlier skarn mineralization in the area (83–89 Ma). This study presents the first comprehensive geochemical dataset for the Galale deposit, refines its metallogenic model, and identifies key geochemical indicators (e.g., Sr, Y, Nb, Rb, Zr, Hf) for Mo exploration. Full article

This research introduces a synergistic photoelectrocatalytic (PEC) system designed for the effective degradation of tetracycline (TC), integrating a PO₄³⁻-grafted Mo-doped BiVO₄ (PO₄³⁻-Mo:BiVO₄) photoanode with a Pd-loaded ordered mesoporous carbon (Pd/CMK-3) cathode. The incorporation of Mo doping and PO₄³⁻ modification significantly improved the photoanode’s charge separation efficiency, achieving a photocurrent density of 2.9 mA cm⁻², and fine-tuned its band structure to enhance hydroxyl radical (·OH) generation. Meanwhile, the Pd/CMK-3 cathode promoted a two-electron oxygen reduction reaction pathway, producing hydrogen peroxide (H₂O₂) and facilitating molecular oxygen activation via atomic hydrogen (H*) intermediates. Under optimized conditions—1.0 V vs. Ag/AgCl of anodic potential, pH 6.58, and oxygen saturation—the combined system accomplished 80% TC degradation within 60 min, markedly surpassing the performance of the photoanode (72%) or cathode (71%) alone. Notably, this synergistic approach also reduced energy consumption to 0.0065 kWh m⁻³, outperforming individual components. Radical quenching experiments and liquid chromatography–mass spectrometry (LC-MS) analysis revealed that the photogenerated holes (h⁺) and ·OH were the key reactive species responsible for TC mineralization. The system demonstrated remarkable stability, with only a 2.96% decline in activity, and effectively degraded other contaminants, such as phenol, 4-chlorophenol, and ciprofloxacin. This study highlights an energy-efficient PEC strategy that harnesses the combined strengths of anodic oxidation and cathodic molecular oxygen activation to significantly enhance the removal of organic pollutants. Full article

The induction quenching–tempering process typically enhances the surface strength and core toughness of alloy steels by utilizing the skin effect. However, the impact of parameters like quenching current and heating time on the microstructure and mechanical property of 34CrNiMo6 steel crankshafts remains unclear. In this work, the microstructure of 34CrNiMo6 steel after induction quenching exhibits three distinct zones: a martensite hardened layer; a transition zone of martensite and tempered sorbite; and a matrix of tempered sorbite. As the induction current (400, 500, and 600 mA) and heating time (3, 5, and 7 s) increase, the hardened layer thickness enhances (up to 3.21 mm). Under the 600 mA and 7 s, the hardened layer reaches peak hardness and residual stress values of 521.48 HV and −330.12 MPa, showing a decreasing trend from surface to core. After tempering at 330 °C for 2 h, the hardened layer mainly consists of tempered martensite, and the surface hardness and residual stress decrease to 417.94 HV and −12.33 MPa. The temperature gradient from quenching balances after tempering, with martensitic phase transformation and stress redistribution reducing hardness and residual stress. Furthermore, the induction quenching–tempering process enhances the toughness of 34CrNiMo6 steel when compared to the untreated specimen, boosting its tensile yield strength, elongation, and tensile strength by 15.3%, 14.9%, and 19.5%, respectively. This work deepens the understanding of induction quenching–tempering process and provides valuable insights for designing alloy steels with excellent mechanical properties. Full article

The development of ternary metal oxide electrocatalysts with optimized electronic structures and surface morphologies has emerged as one of the effective strategies to improve the performance of electrochemical water splitting. In this work, ternary CoMoCe (CMC)-oxide electrocatalysts were successfully synthesized on nickel foam substrates via a hydrothermal technique and employed for their catalytic activity in an alkaline electrolyte. For comparison, binary counterparts (CoMo, CoCe, and MoCe) were also fabricated under similar conditions. The synthesized catalysts’ electrodes exhibited diverse surface architectures, including microporous-flake hybrids, ultrathin flakes, nanoneedle-assembled microspheres, and randomly oriented hexagonal structures. Among them, the ternary CoMoCe-oxide electrode exhibited outstanding bifunctional electrocatalytic activity, delivering low overpotentials of 124 mV for the hydrogen evolution reaction (HER) at −10 mA cm⁻², and 340 mV for the oxygen evolution reaction (OER) at 100 mA cm⁻², along with excellent durability. Furthermore, in full water-splitting configuration, the CMC||CMC and RuO₂||CMC electrolyzers required cell voltages of 1.69 V and 1.57 V, respectively, to reach a current density of 10 mA cm⁻². Remarkably, the CMC-based electrolyzer reached an industrially relevant current density of 1000 mA cm⁻² at a cell voltage of 2.18 V, maintaining excellent stability over 100 h of continuous operation. These findings underscore the impact of an optimized electronic structure and surface architecture on design strategies for high-performance ternary metal oxide electrocatalysts. Herein, a robust and straightforward approach is comprehensively presented for fabricating highly efficient ternary metal-oxide catalyst electrodes, offering significant potential for scalable water splitting. Full article

To enhance the safe service performance of corrosion-resistant tank steel, it is of significant importance to develop novel materials characterized by both high strength-toughness and a low yield ratio. In this study, four experimental steels with a gradient of Mo content (0, 0.15 wt%, 0.30 wt%, and 0.60 wt% Mo) were prepared via thermomechanical controlled processing. The influence of Mo on the microstructural evolution and mechanical properties of the base metal was systematically investigated. The results revealed that when the Mo content was ≤0.15 wt%, the primary constituents of the matrix microstructure were polygonal ferrite, acicular ferrite, and granular bainitic ferrite. As the Mo content increased to 0.30 wt% and beyond, lath bainitic ferrite (LBF) emerged within the microstructure, and the size of the hard martensite/austenite constituents exhibited a refinement trend with increasing Mo content. Elevated Mo content enhanced the strength of the base metal, while the impact toughness initially increased and subsequently decreased. The equivalent grain size defined by misorientation tolerance angles of 2–6° contributed most significantly to the yield strength, as evidenced by its higher Hall–Petch fitting coefficient. The improvement in impact toughness was primarily attributed to the refinement of M/A constituents, which reduced crack initiation susceptibility, and the high density of high-angle grain boundaries (HAGBs) provided by the acicular ferrite. Conversely, the degradation in toughness was directly correlated with the coarsening of HAGB size and the reduction in HAGB density induced by the formation of LBF. Full article

Migraine is a prevalent neurological disorder that affects over 1 billion individuals worldwide. The pathogenesis of migraine remains incompletely understood, though evidence suggests a multifactorial etiology involving genetic factors. The CACNA1A gene has been implicated in rare forms of Familial Hemiplegic Migraine (FHM). This study aimed to investigate the role of CACNA1A variants in individuals with and without a family history of migraine. We genotyped 150 subjects (100 migraine patients: 50 with migraine without aura (MO), 50 with migraine with aura (MA) and 50 controls) for six CACNA1A variants using Sanger sequencing. Statistical analyses were performed in Statistica (p < 0.05). The CADD v1.7 model was used to assess the potential pathogenicity of novel variants. Three variants described in databases (rs10405121, rs894252513, and rs1012663275) and three novel variants (ch19:13228374 G > C, ch19:13228428 G > C, and ch19:13228348 A > T) were identified. The rs10405121 variant was associated with both migraine types, with the homozygous AA genotype exclusively found in familial cases. Abnormal genotype of rs894252513 and rs1012663275 were detected only in familial cases with MO. The novel variants were observed exclusively in patients with a family history of migraine, suggesting their potential relevance to inherited migraine pathogenesis. Novel variants may contribute to migraine pathogenesis by altering calcium channel function and lowering the threshold for cortical spreading depression (CSD). Full article

Electrocatalytic water splitting has been demonstrated to be a highly efficient and promising technology for green hydrogen production. However, the inefficiency and instability of the cathode hinder its wide application in water electrolysis. Herein, we report a rapid Joule heating method for synthesizing the Ru-Mo oxide catalyst. Comprehensive characterization results confirmed that the as-prepared catalyst featured an internal porous structure with low crystallinity, which weakened the strength of Ru-H bonds through structural and electronic modulation. The enhanced HER performance was attributed to the incorporation of Mo⁴⁺ species, which strengthened Ru-O-Mo interactions. As tested, the optimized catalyst exhibited ultralow overpotentials (25.08 mV and 120.52 mV @ 10 and 100 mA cm⁻², respectively) and excellent stability (100 h @ 100 mA cm⁻²) in a 1 M KOH solution. Meanwhile, the as-prepared catalyst was equipped in an anion exchange membrane (AEM) alkaline water electrolyzer, which could deliver 185 mA cm⁻² at only 2.16 V with 100% Faradaic efficiency. This study provides a feasible strategy for constructing highly efficient low-crystallinity electrocatalysts. Full article

The Chating Cu-Au and Magushan Cu-Mo deposits in Anhui province are two representative deposits within the recently defined Nanling-Xuancheng ore concentration area in the Middle and Lower Yangtze River Metallogenic Belt (MLYB). Magmatism and mineralization for the area are not well known at present due to a lack of in-depth studies on the petrogenesis of ore-bearing intrusive rocks and their relationship with deposits. Here, the ore-bearing intrusive rocks of the two deposits are investigated through analyses of whole-rock geochemistry and Sr-Nd isotopes, zircon U-Pb ages, and zircon Hf isotopes. The results reflect the two intrusions, both formed in the Early Cretaceous (138.9 ± 0.8 Ma and 132.2 ± 1.3 Ma). They belong to the sub-alkaline high-K calc-alkaline series, while trace elements are enriched in LILEs and LREE and depleted in HFSEs. However, the intrusions of the Chating deposit (I_sr = 0.7064–0.7068; ε_Nd(t) = −8.5–−7.3; ε_Hf(t) = −11.9–−7.0) have obviously different Sr-Nd-Hf isotopic compositions from the intrusions of the Magushan deposit (I_sr = 0.7079–0.7081; ε_Nd(t) = −5.7–−5.4; ε_Hf(t) = −5.4–−3.6). The characteristics indicate that the two intrusions were formed in the same diagenetic ages and tectonic settings and derived from a crust–mantle mixture with predominant mantle-derived materials. But the crust materials of sources are different, which further leads to different metallogenic elements, showing that the Chating deposit is enriched in Cu and Au, while the Magushan deposit is enriched in Mo. Moreover, the characteristics and magma sources of two intrusions and metallogenic elements correspond respectively to the Tongling Cu-Au polymetallic ore concentration area in the MLYB and the southern Anhui Mo polymetallic ore concentration area in the Jiangnan orogen. The correlation implies differences in magmatism and mineralization between the northwestern and southeastern parts of the Nanling-Xuancheng ore concentration area, demarcated by the Jiangnan Deep Fault. These variations were mainly controlled by the Pre-Sinian crustal basement. Full article

The complex system of high-entropy materials makes it challenging to reveal the specific function of each site for oxygen evolution reaction (OER). Here, with nickel foam (NF) as the substrate, FeCoNiCrMo/NF is designed to be prepared by metal–organic frameworks (MOF) as a precursor under an argon atmosphere. XRD analysis confirms that it retains a partial MOF crystal structure (characteristic peak at 2θ = 11.8°) with amorphous carbon (peaks at 22° and 48°). SEM-EDS mapping and XPS demonstrate uniform distribution of Fe, Co, Ni, Cr, and Mo with a molar ratio of 27:24:30:11:9. Electrochemical test results show that FeCoNiCrMo/NF has excellent OER characteristics compared with other reference prepared samples. FeCoNiCrMo/NF has an overpotential of 285 mV at 100 mA cm⁻² and performs continuously for 100 h without significant decline. The OER mechanism of FeCoNiCrMo/NF further reveal that Co and Ni are true active sites, and the dissolution of Cr and Mo promote the conversion of active sites into MOOH following the lattice oxygen mechanism (LOM). The precipitation–dissolution equilibrium of Fe also plays an important role in the OER process. The study of different reaction sites in complex systems points the way to designing efficient and robust catalysts. Full article

Precise Re-Os isotopic ages of the Jinduicheng and Donggou Mo deposits in the East Qinling orogenic belt can shed light on the controversies about multiple-stage pulses of mineralization and further elucidate the genesis and metallogenic process of the deposits. In this study, we propose two major events of Mo mineralization in this orogenic belt occurring during the Late Mesozoic: the early stage of 156–130 Ma and late stage of 122–114 Ma. Results of molybdenite Re-Os isotopic analysis reveal that the Jinduicheng deposit formed at 139.2 ± 2.9 Ma, while the Donggou deposit exhibited two-stage mineralization at 115.4 ± 1.6 Ma and 111.9 ± 1.3 Ma. These isotopic ages align with the spatiotemporal evolution of coeval ore-barren granites exposed in eastern Qinling, pointing to a close genetic relationship between the magmatism and mineralization that was controlled by the same tectonic activity, likely in a post-collisional setting. This highlights the multiple-stage Mo mineralization and provides evidence for further understanding the geodynamics and metallogenic process in the eastern Qinling orogenic belt. Full article

This study explores the magmatic and hydrothermal evolution of porphyry–skarn–transitional Cu-Mo-W-Au systems within the Nilüfer Mineralization Complex (NMC), located in the westernmost segment of the Eocene Tavşanlı Metallogenic Belt, NW Türkiye. Through integration of field data, whole-rock geochemistry, Re–Os molybdenite dating, and amphibole–biotite mineral chemistry, the petrogenetic controls on mineralization across four spatially associated mineralized regions (Kirazgedik, Güneybudaklar, Kozbudaklar, and Delice) were examined. The earliest and thermally most distinct phase is represented by the Kirazgedik porphyry system, characterized by high temperature (~930 °C), oxidized quartz monzodioritic intrusions emplaced at ~2.7 kbar. Rising fO₂ and volatile enrichment during magma ascent facilitated structurally focused Cu-Mo mineralization. At Güneybudaklar, Re–Os geochronology yields an age of ~49.9 Ma, linking Mo- and W-rich mineralization to a transitional porphyry–skarn environment developed under moderately oxidized (ΔFMQ + 1.8 to +0.5) and hydrous (up to 7 wt.% H₂O) magmatic conditions. Kozbudaklar represents a more reduced, volatile-poor skarn system, leading to Mo-enriched scheelite mineralization typical of late-stage W-skarns. The Delice system, developed at the contact of felsic cupolas and carbonates, records the broadest range of redox and fluid compositions. Mixed oxidized–reduced fluid signatures and intense fluid–rock interaction reflect complex, multistage fluid evolution involving both magmatic and external inputs. Geochemical and mineralogical trends—from increasing silica and Rb to decreasing Sr and V—trace a systematic evolution from mantle-derived to felsic, volatile-rich magmas. Structurally, mineralization is controlled by oblique fault zones that localize magma emplacement and hydrothermal flow. These findings support a unified genetic model in which porphyry and skarn mineralization styles evolved continuously from multiphase magmatic systems during syn-to-post-subduction processes, offering implications for exploration models in the Western Tethyan domain. Full article

The development of efficient platinum group metal-free (PGM-free) catalysts for the hydrogen evolution reaction (HER) and the hydrogen oxidation reaction (HOR) is essential for advancing hydrogen-based energy technologies. In this study, Ni_xMo_100−x composites supported on Carbon Ketjenblack EC-300J (CK) were synthesized via thermal reduction under a controlled Ar/H₂ (95:5) atmosphere to investigate the effect of the Ni/Mo molar ratio on electrocatalytic performance. Structural and morphological analyses by XRD and TEM confirmed the formation of the NiMo alloys and carbide phases with controlled particle size distributions (~18 nm), while BET measurements revealed specific surface areas up to 124.69 m² g⁻¹ for the Pt-loaded samples. Notably, the 3% Pt/Ni₉₀Mo₁₀-CK catalyst exhibited outstanding bifunctional activity in a half-cell configuration, achieving an overpotential of 65.2 mV and a Tafel slope of 41.6 mV dec⁻¹ for the HER, and a Tafel slope of 32.9 mV dec⁻¹ with an exchange current density of 1.03 mA cm⁻² for the HOR. These results demonstrate that compositional tuning and minimal Pt incorporation synergistically enhance the catalytic efficiency, providing a promising platform for next-generation hydrogen electrocatalysts. Full article

Layered transition metal dichalcogenides (TMDs) have gained considerable attention as promising cathodes for aqueous zinc-ion batteries (AZIBs) because of their tunable interlayer architecture and rich active sites for Zn²⁺ storage. However, unmodified TMDs face significant challenges, including limited redox activity, sluggish kinetics, and insufficient structural stability during cycling. These limitations are primarily attributed to their narrow interlayer spacing, strong electrostatic interactions, the large ionic hydration radius, and their high binding energy of Zn²⁺ ions. To address these restrictions, an in situ organic polyaniline (PANI) intercalation strategy is proposed to construct molybdenum disulfide (MoS₂)-based cathodes with extended layer spacing, thereby improving the zinc storage capabilities. The intercalation of PANI effectively enhances interplanar spacing of MoS₂ from 0.63 nm to 0.98 nm, significantly facilitating rapid Zn²⁺ diffusion. Additionally, the π-conjugated electron structure introduced by PANI effectively shields the electrostatic interaction between Zn²⁺ ions and the MoS₂ host, thereby promoting Zn²⁺ diffusion kinetics. Furthermore, PANI also serves as a structural stabilizer, maintaining the integrity of the MoS₂ layers during Zn-ion insertion/extraction processes. Furthermore, the conductive conjugated PANI boosts the ionic and electronic conductivity of the electrodes. As expected, the PANI–MoS₂ electrodes exhibit exceptional electrochemical performance, delivering a high specific capacity of 150.1 mA h g⁻¹ at 0.1 A g⁻¹ and retaining 113.3 mA h g⁻¹ at 1 A g⁻¹, with high capacity retention of 81.2% after 500 cycles. Ex situ characterization techniques confirm the efficient and reversible intercalation/deintercalation of Zn²⁺ ions within the PANI–MoS₂ layers. This work supplies a rational interlayer engineering strategy to optimize the electrochemical performance of MoS₂-based electrodes. By addressing the structural and kinetic limitations of TMDs, this approach offers new insights into the development of high-performance AZIBs for energy storage applications. Full article

Microbial contamination and biofilm formation on food contact materials (FCMs) represent critical challenges within the food supply chain, compromising food safety and quality while increasing the risk of foodborne illnesses. Traditional materials often lack sufficient microbial resistance to contamination, creating a high demand for innovative antimicrobial surfaces. This study assessed the effectiveness of a nanosized deposited SiO_xC_yH_z coating approved for food contact on 3D-printed polyamide 12 (PA12) disk substrates, aiming at providing antimicrobial and anti-biofilm functionality to mechanical components and packaging material in the food supply chain. The coating was applied using plasma-enhanced chemical vapor deposition (PECVD) and characterized through Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and contact angle measurements. Coated PA12 samples exhibited significantly enhanced hydrophobicity, with an average water contact angle of 112.9°, thus improving antibacterial performance by markedly reducing bacterial adhesion. Microbiological assays revealed a significant (p < 0.001) bactericidal activity (up to 4 logarithms after 4 h, ≥99.99%) against Gram-positive and Gram-negative bacteria, including notable foodborne pathogens such as L. monocytogenes, S. aureus, E. coli, and S. typhimurium. SiO_xC_yH_z-coated PA12 surfaces exhibited strong antibacterial activity, representing a promising approach for coating additive-manufactured components and equipment for packaging production in the food and pharmaceutical supply chain able to enhance safety, extend product shelf life, and reduce reliance on chemical sanitizers. Full article

This paper introduces a high-efficiency buck converter designed for a wide load range, targeting low-power applications in medical devices, smart homes, wearables, IoT, and technology utilizing WiFi and Bluetooth. To achieve high efficiency across varying loads, the proposed converter employs a low-power adaptive on-time (AOT) controller that ensures output voltage stability and seamless mode transitions. An adaptive comparator (ACP) with variable output impedance is introduced, offering a variable DC gain and bandwidth to be suitable for different load conditions. A negative-level shifter (NLS) circuit, with its swing ranging from −0.5 V to the battery voltage (V_BAT), is proposed to control the smaller power p-MOS transistors. By using an NLS, the chip area, which is mostly occupied by power CMOS transistors, is reduced while the power efficiency is improved, particularly under a heavy load. A status time detector (STD) block which provides control signals to the ACP and NLS for optimized power consumption is added to identify load conditions (heavy, light, ultra-light). By employing a 180 nm CMOS technology, the active chip area occupies about 0.31 mm². With an input voltage range of 2.8–3.3 V, the controller’s current consumption ranges from 1.2 μA to 16 μA, corresponding to the output load current varying from 12 μA to 120 mA. Although the output load can vary, the output voltage is regulated at 1.2 V with a ripple between 3 and 12 mV. The proposed design achieves a peak efficiency of 96.2% under a heavy load with a switching frequency of 1.3 MHz. Full article