Search Results (553)

With the dual challenges of global energy scarcity and worsening environmental issues, the efficient and selective conversion of CO₂ into CH₄-an environmentally friendly fuel with high energy density—offers considerable application potential. In this study, a 2D-Cu₂O/carbon nitride (2D-Cu₂O/CN) heterojunction catalyst was successfully prepared. Notably, 2D-Cu₂O/CN shows enhanced light absorption capacity, reduced charge-transfer resistance, and efficient separation of photogenerated electron–hole pairs. It exhibits a CH₄ yield of 14.1 μmol·g⁻¹·h⁻¹, 4-fold higher than that of CN. This study provides a feasible approach for the design of high-efficiency photocatalysts for CO₂ reduction to CH₄. Full article

Background: Chronic urticaria (CU) is characterized by recurrent wheals and/or angioedema persisting for more than six weeks. While disease triggers are often unidentified, seasonal and environmental factors may modulate disease activity; however, evidence regarding their clinical impact remains limited. Objective: This study aimed to evaluate the effects of seasonal, meteorological, and pollutant-specific environmental factors on urticaria control using the Urticaria Control Test (UCT), and to compare these effects between chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIU) in relation to inflammatory serum biomarkers. Materials and Methods: This prospective observational study was conducted at the Allergy and Clinical Immunology outpatient clinic of Kirikkale University Faculty of Medicine between 1 June 2023 and 1 April 2024. Patients with CU were classified as CSU or CIU according to international guidelines. Each participant was evaluated during summer and winter seasons. Area-level air pollution data and meteorological parameters were obtained from national monitoring systems. Disease control was assessed using the UCT, and inflammatory biomarkers were analyzed. Results: Urticaria control showed significant seasonal variation, with lower UCT scores during summer and higher scores during winter in both CSU and CIU patients. Among environmental factors, ozone (O₃) was the only pollutant consistently associated with poorer urticaria control, whereas particulate matter and traffic-related pollutants, despite being higher in winter, showed no clinically relevant association. Summer months were characterized by increased inflammatory activity, including elevated leukocyte counts, neutrophil-to-lymphocyte ratio (NLR), C-reactive protein (CRP), and D-dimer levels, particularly in CSU patients. D-dimer emerged as an independent marker associated with poor disease control during summer. Conclusions: CU demonstrates marked seasonal variation, with disease worsening during summer months. Pollutant-specific effects, particularly O₃ exposure, rather than overall air pollution burden, appear to be clinically relevant in urticaria control. Inflammatory and coagulation-related biomarkers may provide additional insight into disease activity. These findings support a season-aware and individualized management approach and highlight the need for future studies incorporating individual-level exposure assessment and biomarker-guided strategies. Full article

Metal oxide nanomaterials have emerged as transformative materials in the quest to enhance the energy density and overall performance of lithium-ion batteries (LIBs) and solid-state batteries (SSBs). Their unique properties—including their large surface areas and short ion diffusion pathways—make them ideal for next-generation energy storage technologies. In LIBs, the high surface-to-volume ratio of metal oxide nanomaterials significantly enlarges the active interfacial area and shortens the lithium-ion diffusion paths, leading to an improved high-rate performance and enhanced energy density. Transition metal oxides (TMOs) such as nickel oxide (NiO), copper oxide (CuO), and zinc oxide (ZnO) have demonstrated significant theoretical capacities, while binary systems like NiCuO offer further improvements in cycling stability and energy output. Additionally, layered lithium-based TMOs, particularly those incorporating nickel, cobalt, and manganese, have shown remarkable promise in achieving high specific capacities and long-term stability. The synergistic integration of metal oxides with carbon-based nanostructures, such as carbon nanotubes (CNTs), enhances the electrical conductivity and structural durability further, leading to a superior electrochemical performance in LIBs. In SSBs, the use of oxide-based solid electrolytes like garnet-type Li₇La₃Zr₂O₁₂ (LLZO) and sulfide-based electrolytes has facilitated the development of high-energy-density systems with excellent ionic conductivity and chemical stability. However, challenges such as high interfacial resistance at the electrode–electrolyte interface persist. Strategies like the application of lithium niobate (LiNbO₃) coatings have been employed to enhance interfacial stability and maintain electrochemical integrity. Furthermore, two-dimensional (2D) metal oxide nanomaterials, owing to their high active surface areas and rapid ion transport, have demonstrated considerable potential to boost the performance of SSBs. Despite these advancements, several challenges remain. Morphological optimization of nanomaterials, improved interface engineering to reduce the interfacial resistance, and solutions to address dendrite formation and mechanical degradation are critical to achieving the full potential of these materials. Full article

We report a galvanic replacement-driven strategy for the in situ growth of highly uniform one-dimensional (1D) Cu@CuO-X (X = Ag, Bi) nanobelts directly on aluminum foils. Unlike conventional multi-step coating or hard-template replication strategies, the formation of these heterostructured nanobelts is governed by a spontaneous interfacial galvanic replacement process between Cu and the introduced metal species, ensuring in situ growth and intimate interfacial integration. Comprehensive SEM, TEM, XRD, and XPS characterizations confirm the successful formation of Cu@CuO-Ag and Cu@CuO-Bi architectures, where Bi predominantly exists in the oxidized Bi³⁺ state, forming Bi₂O₃-like surface species. Benefiting from their 1D anisotropic framework and controllable heterointerfaces, this work underscores the distinctiveness and versatility of the self-templated galvanic replacement strategy for the design of multifunctional nanomaterials. Full article

The increasing impact of global warming is predominantly driven by the extensive use of fossil fuels, which release significant amounts of greenhouse gases into the atmosphere. This has led to a critical need for alternative, sustainable energy sources that can mitigate environmental impacts. Photovoltaic technology has emerged as a promising solution by harnessing renewable energy from the sun, providing a clean and inexhaustible power source. Perovskite solar cells (PSCs) are a class of hybrid organic–inorganic solar cells that have recently attracted significant scientific attention due to their low cost, relatively high efficiency, low–temperature processing routes, and longer carrier lifetimes. These characteristics make them a viable alternative to traditional fossil fuels, reducing the carbon footprint and contributing to the fight against global warming. In this study, the SCAPS–1D numerical simulator was used in the computational analysis of a PSC device with the configuration FTO/ETL/BaZr(S_0.6Se_0.4)₃/HTL/Ir. Different hole transport layer (HTL) and electron transport layer (ETL) material were proposed and tested. The HTL materials included copper (I) oxide (Cu₂O), 2,2′,7,7′–Tetrakis(N,N–di–p–methoxyphenylamine)9,9′–spirobifluorene (spiro–OMETAD), and poly(3–hexylthiophene) (P₃HT), while the ETLs included cadmium suphide (CdS), zinc oxide (ZnO), and [6,6]–phenyl–C₆₁–butyric acid methyl ester (PCBM). Finally, BaZr(S_0.6Se_0.4)₃ was proposed as an absorber, and a fluorine–doped tin oxide glass substrate (FTO) was proposed as an anode. The metal back contact used was iridium. Photovoltaic parameters such as short circuit density (I_sc), open circuit voltage (V_oc), fill factor (FF), and power conversion efficiency (PCE) were used to evaluate the performance of the device. The initial simulated primary device with the configuration FTO/CdS/BaZr(S_0.6Se_0.4)₃/spiro–OMETAD/Ir gave a PCE of 5.75%. Upon testing different HTL materials, the best HTL was found to be Cu₂O, and the PCE improved to 9.91%. Thereafter, different ETLs were also inserted and tested, and the best ETL was established to be ZnO, with a PCE of 10.10%. Ultimately an optimized device with a configuration of FTO/ZnO/BaZr(S_0.6Se_0.4)₃/Cu₂O/Ir was achieved. The other photovoltaic parameters for the optimized device were as follows: FF = 31.93%, J_sc = 14.51 mA cm⁻², and V_oc = 2.18 V. The results of this study will promote the use of environmentally benign BaZr(S_0.6Se_0.4)₃–based absorber materials in PSCs for improved performance and commercialization. Full article

This study investigates the microwave absorption properties of the cuprate ceramic material Bi_1.7Pb_0.3Sr₂Ca₂Cu₃O₁₀ (BSCCO) and its composites with bismuth oxide (Bi₂O₃) in the 4–25 GHz frequency range. Composites with varying BSCCO contents were fabricated and characterized using the Nicolson–Ross–Weir method and Agilent Materials Measurement Software 85071E to determine complex permeability and permittivity. The 4 wt.% BSCCO composite exhibited a peak reflection loss of −32.6 dB at 12.5 GHz, while the 40 wt.% BSCCO composite reached a 52% microwave absorption ratio at 23 GHz. These results demonstrate that microwave absorption is strongly influenced by dielectric properties and the ratio of BSCCO and Bi₂O₃ composites. This work highlights the potential of BSCCO-Bi₂O₃ ceramics for microwave absorption applications, particularly in environments experiencing significant temperature gradients due to their thermal stability and electromagnetic performance. Full article

Optimizing copper recovery from sulfide minerals such as chalcopyrite, which constitutes over 70% of global copper reserves, is essential due to the depletion of conventional copper oxide resources. This study aimed to establish optimal ferric leaching conditions for a chalcopyrite-rich concentrate to maximize copper recovery and to evaluate the regeneration of the oxidizing potential in the residual leaching solution for reuse. Ferric sulfate (Fe₂(SO₄)₃), as a ferric ion (Fe³⁺) carrier, was used as oxidizing agents at a concentration of [0.1 M] in sulfuric acid ([0.5 M] H₂SO₄), using a CuFeS₂ concentrate (75% chalcopyrite) leached over 80 h. Copper was recovered through cementation with metallic iron, while the residual leaching solution, containing ferrous ions, was analyzed to determine total iron content via atomic absorption spectroscopy and to assess the presence of ferrous ions through KMnO₄ titration. This step was crucial, as an excess of ferrous ions would indicate a loss of oxidizing potential of the ferric ion (Fe³⁺). Catalytic oxidation was conducted with microporous activated carbon (30 g/L) to regenerate Fe³⁺ for a second leaching cycle, achieving 90.7% Fe²⁺ oxidation. Optimal leaching conditions resulted in 95% soluble copper recovery at 1% solids, d80: 74 μm, pH < 2, Eh > 450 mV, 92 °C, [0.5 M] H₂SO₄, and [0.1 M] Fe₂(SO₄)₃. In the second cycle, the regenerated solution reached 75% copper recovery. These findings highlight temperature as a critical factor for copper recovery and demonstrate catalytic oxidation as a viable method for regenerating ferric solutions in industrial applications. Full article

Lead-free chalcogenide perovskites are emerging as promising alternatives to hybrid halide perovskites due to their superior thermal stability, non-toxicity, and strong optical absorption. In this study, the photovoltaic performance of single-junction BaHfSe₃-based perovskite solar cells (PSCs) with the TCO/TiO₂/BaHfSe₃/Cu₂O/Au configuration is systematically investigated using SCAPS-1D simulations. Device optimization identifies TiO₂ and Cu₂O as suitable ETL and HTL materials, respectively. The optimized structure—TCO/TiO₂ (50 nm)/BaHfSe₃ (500 nm)/Cu₂O (100 nm)/Au—achieves a power conversion efficiency (PCE) of 24.47% under standard conditions. Simulation results reveal that device efficiency is influenced by absorber thickness and trap density. A detailed temperature-dependent study highlights that photovoltaic parameter efficiency is governed by the barrier alignment at the TCO/ETL interface. For lower TCO (Transparent Conducting Oxide) work functions (3.97–4.07 eV), PCE decreases monotonically with temperature, attributed to the increase in reverse saturation current resulting from a higher intrinsic carrier concentration. By contrast, higher TCO work functions (4.47–4.8 eV) yield an initial increase in efficiency with temperature, driven by reduced barrier height and favorable Fermi level shifts before efficiency declines at further elevated temperatures. These insights underscore the promise of BaHfSe₃ as a lead-free, environmentally robust perovskite absorber for next-generation PSCs, and highlight the critical importance of interface engineering for achieving optimal thermal and operational performance. Full article

The extraction and stripping of Co, Ni, Mn, and Mg ions from raffinate solution of the Sarcheshmeh copper complex containing Cu (0.14 g/L), Ni (0.15 g/L), Co (0.06 g/L), Fe (10.72 g/L), Zn (2.4 g/L), Mn (4.83 g/L), and Mg (8 g/L) was comprehensively studied using D2EHPA and LIX 984 extractants. To design the solvent extraction experiments, the response surface method (RSM) was employed. The optimal and most efficient conditions and extraction rates of nickel and cobalt were considered for the application of a central composite design (CCD). The design of experiments (DOE) was carried out using three operating variables: the equilibrium pH of the solution (4–6), extractant concentration (10–20%), and aqueous-to-organic phase ratio (1–3). The results indicated that the highest extraction of Co and Ni occurred within 5 min at a mixing speed of 500 r/min and 40 °C. The results showed that the equilibrium pH of the aqueous solution had a greater influence on nickel and cobalt extraction than the other parameters. According to the research results, 99% of cobalt and 94% of nickel were extracted simultaneously under optimum conditions of pH = 6, [LIX984N] = 10%, and A/O = 3. In the stripping stage, 95% of nickel ions were recovered in one step using 1 M sulfuric acid, and 80% of cobalt ions were recovered in three steps using 5 M hydrochloric acid. Finally, 98% of Zn, 99% of Co, and 94% of Ni were extracted in two stages with D2EHPA and LIX984N extractants. Full article

Flax (Linum usitatissimum L.) is a multipurpose crop known for its highly nutritious seeds. This study aimed to determine how plant density and fertilizer type influence the nutritional composition of flaxseed, addressing a gap in the literature where combined effects on seed quality have not been thoroughly evaluated. Two plant densities (D1, 500 plants m⁻²; D2, 300 plants m⁻²) and four fertilizers (control, C; inhibited urea, I; organic, O; and urea, U), were compared. According to the results, the interactions of these factors influenced most of the traits. The highest yields were reported at D1I. Organic fertilization improved protein (7%) and fat (28%) content and reduced fiber (46%) and carbohydrates. In contrast, inorganic fertilization increased fiber, NDF (10%) and ADF (8%) content. Mineral composition was also affected, with O and I increasing K, Mg, Fe and Cu by 31%, 6%, 14% and 24% for O and 48%, 1%, 17% and 18%, respectively, for I. The correlation matrix analysis revealed a positive relationship between protein and fat content, whereas both traits were negatively correlated with fiber and carbohydrates. Overall, optimized density and fertilizer can improve the quality of flaxseed, supporting its use as functional food and feed ingredient. Full article

In this work, we analyze how the coupling prism governs the performance of reduced-graphene-oxide (rGO)-assisted surface plasmon resonance (SPR) sensors for trace heavy-metal detection in water. A Kretschmann multilayer at 633 nm with a fixed Cu/Si₃N₄/rGO stack (45.0/5.00/1.41 nm) is modeled by transfer-matrix methods while varying the prism material among CaF₂, BK7, SiO₂, and SF₆. Performance optimization is carried out using angular sensitivity, full width at half maximum (FWHM), figure of merit (FoM), detection accuracy (DA), quality factor (QF), and a practical limit of detection (LoD). The analyte is represented by refractive-index typical of clean and contaminated water (n = 1.330 and 1.340). SF₆ yields the narrowest angular resonances but compresses analyte-induced angle spacing; CaF₂ provides larger analyte separations and consequently higher FoM and lower LoD under angle-encoded readout. The rGO interlayer enhances surface interaction across all prisms when co-tuned with the Cu and Si₃N₄ thicknesses. The sensitivity peaks around 310–320°·RIU⁻¹ for CaF₂. These results highlight the prism as a primary design variable in rGO-enhanced SPR sensing and position CaF₂-coupled architectures as promising for compact water-quality monitoring. Full article

This study investigated the solvent extraction of a high-nickel-content metal solution using nickel-preloaded extractants. A synthetic high-nickel lithium-ion battery (LIB) black mass leachate was prepared to extract Cu, Al, and Mn using Ni-preloaded D2EHPA (Ni-D2EHPA). Then, Co was extracted from the raffinate using Ni-preloaded PC88A (Ni-PC88A). The results showed that Ni-preloaded D2EHPA extracted more than 99% of the Al, Cu, and Mn. Co was also co-extracted at a rate of 53%, but 99% of the Co was scrubbed with 0.2 M H₂SO₄. Co was extracted from the raffinate using Ni-PC88A at a rate of 99% with 1.0 O/A. Finally, 99% of the Co in the organic phase was stripped using 2.0 M sulfuric acid. After Co extraction using Ni-PC88A, 80 g/L Ni and 1.38 g/L Li remained in the raffinate. Crude nickel sulfate was produced from the raffinate after precipitation of Li as lithium carbonate. Full article

A recently discovered turquoise deposit in the Fangshankou area of Dunhuang, Gansu Province, has been relatively understudied compared to turquoise from other sources due to its short mining history. Currently, no relevant research literature on this deposit has been identified. Therefore, a systematic mineralogical and spectroscopic study of Dunhuang turquoise samples was conducted using conventional gemological testing methods, combined with techniques such as X-ray powder diffraction (XRD), electron probe microanalysis (EPMA), Fourier transform infrared spectroscopy (FTIR), laser Raman spectroscopy, ultraviolet-visible spectroscopy (UV-Vis), and X-ray fluorescence (XRF) mapping. The test results indicate that the turquoise samples from this area have a density ranging from 2.40 to 2.77 g/cm³ and a refractive index between 1.59 and 1.65. The samples generally exhibit a cryptocrystalline structure, with some displaying spherulitic radial and radial fibrous structures. The texture is relatively dense and hard, with particle diameters less than 10 μm. Chemically, the turquoise samples from this region are characterized by high Fe and Si content and relatively low Cu content. Samples contain, in addition to the turquoise mineral, other minerals such as quartz, goethite and alunite, etc. The oxide content ranges are as follows: w(P₂O₅) between 23.83% and 33.66%, w(Al₂O₃) between 26.47% and 33.36%, w(CuO) between 5.26% and 7.91%, w(FeO) between 2.46% and 4.11%, and w(SiO₂) between 0.97% and 10.75%. In the infrared absorption spectra of Dunhuang turquoise, the bands at 3510 cm⁻¹ and 3464 cm⁻¹ are attributed to ν(OH)⁻ stretching vibrations, while the bands near 3308 cm⁻¹ and 3098 cm⁻¹ are assigned to ν(M-H₂O) stretching vibrations. The infrared absorption bands near 1110 cm⁻¹ and 1058 cm⁻¹ are due to v[PO₄]³⁻ stretching vibrations, and the bands near 651 cm⁻¹, 575 cm⁻¹, and 485 cm⁻¹ are attributed to δ[PO₄]³⁻ bending vibrations. A clear correlation exists between the Raman spectral features and the infrared spectra of this turquoise. The hue and chroma of the turquoise from this area are primarily influenced by the mass fractions of Fe³⁺, Cu²⁺, and Fe²⁺, as well as their bonding modes with water molecules. The ultraviolet-visible spectra are attributed to O²⁻–Fe³⁺ charge transfer, the ⁶A₁–⁴E_g + ⁴A₁ transition of Fe³⁺ ions (D⁵ configuration) in hydrated iron ions [Fe(H₂O)₆]³⁺, and the spin-allowed ²E_g–²T_2g transition of Cu²⁺ ions in hydrated copper ions [Cu(H₂O)₄]²⁺. Associated minerals include goethite, alunite, jarosite, and quartz. Fine-grained quartz often exists as secondary micron-sized independent mineral phases, which have a certain impact on the quality of the turquoise. Full article

This article investigates the use of bent metal strips on the top of a SiO₂ layer for the suppression of spurious modes in temperature-compensated surface acoustic wave (TC-SAW) resonators employing a SiO₂/Cu/128°YX-LiNbO₃ structure. The proposed metal strip method includes two parts: a primary metal strip located at the edge of the interdigital transducer (IDT) aperture region and a secondary metal strip in the gap region. The impact of the geometric parameters of bent metal strips was calculated by the 3D finite element method (FEM), and theoretical simulation results show that this method can effectively suppress the transverse modes and mitigate the gap modes originating from the gap region in conventional TC-SAW resonators. Furthermore, experimental validation further confirms that the proposed method can effectively suppress nearly all spurious modes without degrading the performance of the quality factor. Full article

The Laoliwan Ag-Pb-Zn deposit is situated in the southern margin of the North China Craton and represents the first large-scale Ag-Pb-Zn ore deposit discovered in the Xiaoshan District. Ag-Pb-Zn orebodies are structurally controlled by NW- and NNW-trending faults and primarily hosted within early Cretaceous granite porphyry intrusions. In this study, sulfide Rb-Sr isotope dating and C-H-O-S-Pb multiple isotope compositions were conducted to constrain the ore genesis of this deposit. The Rb-Sr isotopic data of sulfides yield a weighted mean isochron age of 132.8 ± 9.5 Ma and an initial ⁸⁷Sr/⁸⁶Sr ratio of 0.7115 ± 0.00016, indicating that mineralization occurred during the early Cretaceous and the ore-forming materials were derived from a crust–mantle mixed reservoir. The δ¹³ C (−1.3‰ to 0.7‰), δD (−96.3‰ to −86.7‰) and δ¹⁸O_H2O (0.3‰ to 5.6‰) values suggest that the ore-forming fluids were mainly derived from magmatic water with a contribution of meteoric water during mineralization. The δ³⁴S values of sulfides (+2.0‰ to +5.8‰) indicate a magmatic source. The Pb isotope data (²⁰⁶Pb/²⁰⁴Pb = 17.301–17.892, ²⁰⁷Pb/²⁰⁴Pb = 15.498–15.560, ²⁰⁸Pb/²⁰⁴Pb = 37.873–38.029) also reveal that the ore-forming materials originated from the lower crust with a small amount from the mantle source. By integrating geochronological and geochemical data, this study proposes that the Laoliwan Ag-Pb-Zn deposit is characterized as an epithermal deposit, with potential for the discovery of concealed porphyry Cu-Mo mineralization at depth. It is inferred to be related to tectonic–magmatic–fluid activities in the context of early Cretaceous lithospheric thinning along the southern margin of the North China Craton. Full article