Search Results (6,322)

Oxide systems with the nominal composition LaCaCuVMnO_7.5 and composites modified with the YBa₂Cu₃O_x phase were synthesized by the solid-state reaction method. The phase composition and structural features were systematically investigated by X-ray diffraction (XRD), Rietveld refinement, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDX). The parent oxide was found to form a two-phase system, consisting of an orthorhombic perovskite-like phase and a cubic manganite–vanadate phase, whereas the introduction of 10 wt.% YBa₂Cu₃O_x resulted in the formation of a three-phase composite containing an additional cuprate phase. Thermophysical investigations in the 298–673 K range revealed λ-type-like anomalies in the heat capacity, which may be associated with possible structural or interphase transformations in the investigated oxide systems. The incorporation of YBa₂Cu₃O_x significantly modified the temperature dependence of heat capacity and increased its values over both low- and high-temperature regions. Electrophysical measurements in the 293–483 K range confirmed the semiconducting nature of conductivity, while the addition of YBa₂Cu₃O_x reduced electrical resistance and enhanced dielectric permittivity. These findings demonstrate that YBa₂Cu₃O_x modification provides an effective route for tuning the thermophysical and electrophysical properties of LaCaCuVMnO_7.5-based oxide systems, suggesting their potential as promising candidates for multifunctional oxide materials with possible electronic and sensor-related applications. Full article

This review analyzes electrochemically deposited polyaniline (PANI) nanocomposite thin films containing metallic, semiconducting, and dielectric fillers, including Ag/PANI, Mo/MoO_x/PANI, CeO₂/PANI, Fe₂O₃/PANI, Al₂O₃/PANI, CuO/PANI, Co₃O₄/PANI, and CoFe₂O₄/PANI. The work examines how filler chemistry and loading influence optical-gap evolution, Urbach disorder, dielectric dispersion, nonlinear optical response, structural coherence, and dc conductivity under comparable electrochemical growth conditions. The comparative analysis shows that optical-gap narrowing and conductivity enhancement are not necessarily coupled. Ag/PANI exhibits simultaneous optical softening and improved conductivity, consistent with metallic bridging, dielectric screening, and enhanced charge connectivity. In contrast, Mo/MoO_x/PANI shows strong optical-gap reduction but reduced conductivity, indicating that optically active interfacial states may remain localized or mobility-limiting. Oxide fillers produce additional regimes: CeO₂/PANI can suppress Urbach disorder and microstrain through order stabilization, whereas Al₂O₃/PANI may widen higher-energy transitions and reduce transport through wide-gap barrier effects. Based on these contrasts, a unified framework is proposed that separates the interfacial electronic function from the transport-connectivity function. This approach classifies PANI nanocomposites into transport-assisted metallic, mobility-limiting interfacial, order-stabilized oxide, and barrier-dominated dielectric regimes, providing practical criteria for selecting filler type and loading windows in optoelectronic, sensing, and photonic applications. Full article

The aim of the study was to compare the production results, slaughter value, and physicochemical and biochemical parameters of the muscles of Ross 308 broiler chickens. The study included 225 individuals divided into three groups of 75 birds each. Each group was subdivided into three subgroups of 25 birds each (replicates). The control group received zinc (Zn) in the form of zinc oxide (ZnO) and copper (Cu) in the form of copper (II) sulfate pentahydrate (CuSO₄·5H₂O). Experimental group I received the microelements zinc and copper exclusively in the form of zinc hydroxychloride and dicopper chloride trihydroxide. Experimental group II received zinc and copper in both inorganic and hydroxychloride forms. The obtained results were processed using statistical analysis using the STATISTICA 13.0 [2016] program. The significance of differences between groups was inferred based on Tukey’s test. Chickens from the experimental groups were characterized by higher body weight (p ≤ 0.05) and eviscerated carcass weight (p ≤ 0.05) and better feed utilization (p ≤ 0.05). Moreover, compared with the control group, the carcasses of chickens from the experimental groups were characterized by a lower weight of breast muscles (p ≤ 0.05) and skin with subcutaneous fat, a similar weight of leg muscles, and a significantly greater weight of the remaining carcass components (p ≤ 0.01). The use of Zn and Cu in the form of hydroxychlorides in broiler chicken nutrition increased the fat content in the muscles (p ≤ 0.05), the concentrations of Zn and Cu in the liver, and significantly improved the tibial bone strength of broiler chickens. The application of Zn and Cu in the form of hydroxychlorides in the diets (experimental groups I and II) enhanced lipid and protein oxidation processes and the overall antioxidant capacity in the breast muscle. To conclude, dietary supplementation with zinc and copper hydroxychlorides in broilers promotes growth performance, bone strength, and mineral bioavailability, though it reduces breast muscle yield and triggers oxidative stress in these tissues. Full article

Copper(I) halides are promising for X-ray scintillation owing to high luminescence and solution processability, but their poor stability limits practical use. Here we report a zero-dimensional coordinative cluster, (DPPM)₂Cu₄I₄ (DPPM = bis (diphenylphosphino) methane), prepared by a simple anti-solvent crystallization that emits bright orange light with an absolute photoluminescence quantum yield of 91.11%. Spectroscopic analysis (long lifetime, large Huang–Rhys factor) indicates self-trapped-exciton dominated radiative recombination. The cluster shows outstanding thermal (stable to ≈362 °C), solvent (stable after 30 d in H₂O, EA, EtOH, IPA) and air stability (>60 d), addressing common durability issues of copper(I) halides. Using an in situ growth method, microcrystals of (DPPM)₂Cu₄I₄ were uniformly incorporated into a thermoplastic polyurethane (TPU) matrix to form flexible scintillator films. The composite exhibits a high light yield of 17,064 photons MeV⁻¹ and a spatial resolution of 14 lp mm⁻¹, highlighting its great potential for practical X-ray imaging applications. Full article

Phenolic resin is widely used as a binder in high-temperature industries; however, its pyrolysis generally yields isotropic glassy carbon, which strongly influences its high-temperature oxidation behavior. In this work, cupric tartrate was introduced as a catalyst precursor to investigate its effects on the thermal decomposition behavior, microstructural evolution, and oxidation behavior of the phenolic resin pyrolytic carbon. Upon heating, cupric tartrate decomposed at 250–320 °C into nanoscale Cu/Cu₂O composites, which were then converted into metallic Cu nanoparticles through reduction by gaseous products generated during the pyrolysis of phenolic resin. The in situ formed Cu nanoparticles were associated with the growth of tapered carbon nanofibers (CNFs), reaching maximum lengths of 30–50 μm at 700 °C. Based on the observed microstructural features and established literature reports, a dissolution–precipitation pathway is proposed to rationalize the formation of these CNFs. The presence of Cu-catalyzed CNFs correlates with enhanced structural ordering of the pyrolytic carbon, as reflected by reduced I_D/I_G ratios, and with an increased apparent oxidation activation energy in the selected fitting region (from 103.73 to 137.45 kJ/mol). Overall, this work demonstrates a facile strategy in which cupric tartrate serves as an effective catalyst precursor that generates Cu nanoparticles in situ; these nanoparticles then catalyze CNF growth from phenolic resin, enabling the construction of low-dimensional carbon nanostructures. Full article

In this study, Cu-Fe bimetallic-supported adsorbents were prepared using alkali-activated coconut shell activated carbon (AC-OH) as a carrier by impregnation method. To optimize the adsorption effect, the effects of the second metal type, Fe loading amount, Cu/Fe ratio, and operating conditions on the adsorption effect of extremely low-concentration SO₂ (1 ppm) were systematically investigated. The results showed that when the Cu loading was 5% by mass and the Fe loading was 3% by mass, the adsorbent exhibited optimal adsorption performance, with a breakthrough time of up to 36.5 h and a corresponding breakthrough sulfur capacity of 14.424 mg/g. Further exploration of the conditions shows that the coexistence of O₂ and H₂O can significantly promote the adsorption of SO₂, while reducing the space velocity is beneficial for prolonging the breakthrough time. In terms of regeneration stability, after two adsorption–regeneration cycles, the adsorption activity of the adsorbent decreased to 72.7% of the fresh sample, and the deactivation was mainly attributed to the accumulation of sulfate species and the loss or aggregation of active components. By combining XRD, FT-IR, XPS, SEM and other characterization techniques, the structure–activity relationship and deactivation mechanism of the adsorbent were analyzed. This bimetallic-modified activated carbon has shown great potential for deep purification of extremely low concentrations of SO₂. Full article

Photocatalytic CO₂ reduction into CH₄ is a promising route for solar fuel production, but its efficiency is still limited by poor charge separation, insufficient CO₂ activation, and sluggish multi-electron transfer kinetics. Herein, Cu-modified TiO₂ (Cu/TiO₂) was prepared by calcining a Cu-modified defective MIL-125(Ti) precursor, denoted as Cu-MIL-125, through a temperature-controlled calcination strategy. The effects of calcination temperature on the structural evolution, surface chemical states, interfacial charge transport, and CO₂ photoreduction performance were examined. These results indicated that the Cu/TiO₂ was successfully prepared, while the crystallinity, porous structure, and interfacial electronic properties of Cu/TiO₂ were strongly dependent on the calcination temperature. Among the obtained samples, the Cu/TiO₂ sample obtained by calcining Cu-MIL-125 at 450 °C (450 Cu/TiO₂) exhibited the highest CH₄ formation rate, reaching 15.90 μmol g⁻¹ h⁻¹, corresponding to an approximately 9.8-fold enhancement over TiO₂ calcined from defective MIL-125(Ti) at 450 °C, together with a high CH₄ selectivity of 93.05%. Control experiments and ¹³CO₂ isotope-labeling tests confirmed that the detected carbon-containing products were generated from CO₂ under photocatalytic conditions. In situ diffuse reflectance infrared Fourier transform spectroscopy measurements further revealed the formation of carbonate, bicarbonate and hydrogenated carbon-containing intermediates during the reaction. This work offers a practical route for constructing metal–organic framework-derived Cu/TiO₂ photocatalysts for selective CH₄ production from CO₂. Full article

Rock-forming minerals, olivine and pyroxene, from three ore-bearing intrusions in the Norilsk districts were studied. They are the Norilsk 1 and the Northern and Southern Maslovsky massifs with PGE-Cu-Ni ores, located in the Norilsk syncline. Trace elements such as Al, Ti, Co, Cu, Nd, Sm, Ce, Cr, V, Dy, Y, Yb, Er, Sr, and Eu were determined by LA-ICP-MS. The authors found differences in mineral compositions between picritic gabbro-dolerites from these intrusions. The parental melt of the Southern Maslovsky intrusion corresponded to tholeiitic basalt containing (wt.%) H₂O—0.65, CO₂—0.16, and B—0.004. It was concluded that parental magmas for ore-bearing intrusions had no specific features and were closed to intraplate basalts. Full article

Recently, numerous synthesis methods have been developed for the preparation of nanostructured materials for supercapacitor applications, and top-down strategies have gained increasing attention due to their relative simplicity and reduced processing complexity. In particular, the combustion method is recognized as one of the simplest and most rapid approaches for producing a wide range of materials. Within this study, the combustion of Cu₄₈Zr₄₇Al₅ amorphous ribbons was employed, and the supercapacitor electrodes based on Cu-Cu₂O/ZrO₂ mixed oxide were developed. The morpho-structural properties of the materials were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the electrochemical performance, particularly for supercapacitor applications, was evaluated by cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) measurements. The CV curves indicate that the Cu–Cu₂O/ZrO₂ mixed oxide structure acts as a positive electrode and exhibits a non-rectangular shape, confirming pseudocapacitive behavior of the as-synthesized material. A maximum areal specific capacitance of 472.7 mF cm⁻² was obtained at a scan rate of 5 mV s⁻¹. From GCD analysis, an areal specific capacitance of 336.5 mF cm⁻² was achieved at a current density of 1 mA cm⁻². Cycling stability was evaluated over 1000 charge–discharge cycles, showing an increase in capacitance to 135.14% after the 1000th cycle, attributed to the progressive activation of the electrode material. This study highlights the potential of Cu–Cu₂O/ZrO₂ mixed oxides prepared via self-sustained combustion as efficient and durable electrode materials for supercapacitors. The findings provide a starting point for the future optimization of amorphous alloys for the synthesis of mixed-oxide materials through a scalable fabrication process, paving the way for advanced energy storage applications. Full article

Polylactic acid (PLA)-curcumin (CCM) composites, incorporating various contents of surface-functionalized dual-metal-doped copper oxide (SF-M-CuO), were prepared by the solution casting method. Synthesized composite films were evaluated for their antioxidant, biocompatible, photothermal, and antibacterial properties. The 4% CCM exhibits excellent compatibility based on total color difference, antioxidant activity, and controlled curcumin release behavior. In addition, different contents of SF-M-CuO (1–4%) were added to the PLA-4%-CCM polymer matrix. Synthesized composite films were characterized through functional, structural, and topographical analyses. FTIR and XRD analyses confirmed the successful incorporation of CCM and SF-M-CuO into the PLA matrix, which enhanced interfacial interactions and increased the crystallinity index by acting as effective nucleating agents. ABTS and DPPH radical scavenging assays revealed dose-dependent antioxidant activity due to the synergistic effects of CCM and SF-M-CuO. Biocompatibility evaluation using RAW 264.7 macrophage cells demonstrated non-toxic responses and enhanced cell proliferation in PLA-4%-CCM composite films containing up to 3%-SF-M-CuO. Among the fabricated films, PLA-4%-CCM-3%-SF-M-CuO exhibited superior photothermal performance and excellent antibacterial activity against Staphylococcus aureus and Escherichia coli, reducing bacterial counts to below the limit of detection. These findings demonstrate the potential of PLA-4%-CCM-3%-SF-M-CuO composite films as sustainable multifunctional materials for food safety and biomedical applications. Full article

In this study, catalytic wet oxidation of highly concentrated antibiotic-containing pharmaceutical wastewater was investigated under mild operating conditions (200–280 °C, 2.0~6.0 MPa) using a CuCe/Al₂O₃catalyst, synthesized via the co-impregnation method. The physicochemical properties of the catalyst were characterized by SEM-EDS, TEM, XPS. The catalytic performance results demonstrated that the CuCe/Al₂O₃ catalyst exhibited optimal catalytic activity, achieving a chemical oxygen demand (COD) removal efficiency of 86.3% under the following conditions: reaction temperature 280 °C, reaction time 60 min, initial oxygen pressure 1.2 MPa, and catalyst dosage 5.0 g/L. The superior catalytic performance was attributed to the synergistic effect between Cu and Ce species as well as their excellent dispersion on the support. Kinetic analysis revealed that the oxidation process proceeded via two sequential reaction steps and followed an apparent first-order kinetic model. Overall, this catalytic wet oxidation process offers an efficient pretreatment strategy for highly concentrated pharmaceutical wastewater containing antibiotics. Full article

Microbiologically induced concrete corrosion (MICC) poses a severe challenge to the long-term durability of infrastructure, particularly in sewer networks and marine environments, which is driven by microbial metabolic activities that attack cement hydrates (Ca(OH)₂, C-S-H) mainly caused by biogenic sulfuric acid (from sulfur-oxidizing bacteria) or organic acids (from fungi), converting them into expansive gypsum and ettringite, and then cause cracking and spalling. This article reviews advances in mechanisms, key microorganisms, and protection strategies of MICC to enhance our understanding of MICC and provide a guideline for effective protection. The corrosion mechanisms differ by environment: sewers exhibit three-stage pH-driven succession, marine biofilms can either accelerate or inhibit corrosion, while fungi dominate in agricultural and historical settings. Core functional microorganisms involved in MICC include sulfur-oxidizing bacteria (SOB), sulfate-reducing bacteria (SRB), and acid-producing fungi (AF), following pH-dependent succession, while indicator microorganisms for protection efficacy include typical SOB, SRB, and AF that are involved in MICC, as well as general antimicrobial indicator strains (e.g., Escherichia coli and Staphylococcus aureus) which are used only to assess broad antimicrobial activity and do not represent MICC-specific resistance. Multi-scale deterioration proceeds from microstructural decalcification and pore coarsening to macroscopic mass loss and compressive strength reduction. Protection strategies are categorized into: (i) corrosion-resistant materials (e.g., calcium aluminate cement and alkali-activated materials), (ii) antimicrobial additives (e.g., nano-ZnO and Cu₂O), (iii) surface coatings (e.g., superhydrophobic coatings and electrodeposited Cu/Cu₂O layers), and (iv) ecological regulation. However, significant gaps remain between laboratory efficacy and field performance, highlighting the need for long-term validation, multi-scale characterization, intelligent responsive materials, eco-compatible protection systems, and standardized microbial exposure systems. Full article

In this study, a series of Cu_aZn_bO_x catalysts with tunable Cu/Zn molar ratios were fabricated via a MOF-on-MOF precursor strategy for CO₂ hydrogenation to methanol. The optimal catalyst, Cu₆Zn₄O_x, achieved a CO₂ conversion of 14.4%, a methanol selectivity of 81.1%, and a space-time yield of 902.1 g_MeOH·kg_cat⁻¹·h⁻¹ at 280 °C and 3 MPa with a GHSV of 24,000 mL·g_cat⁻¹·h⁻¹. Characterization results revealed that this strategy successfully constructed small-sized Cu and ZnO particles as well as abundant Cu–ZnO interfaces, reaching the optimal structural and compositional state when the Cu/Zn molar ratio is tuned to 6:4. The effective Cu–ZnO interface on Cu₆Zn₄O_x promotes the CO₂ adsorption and H₂ dissociation, triggering the formation of carbonate species and resulting in the generation of methanol via a carbonate–formate pathway. This work provides a new insight for the rational design of high-performance CO₂ hydrogenation catalysts through precursor interface engineering. Full article

Due to the scarcity and high cost of precious metals, development of a noble metal-free, low-cost catalyst for hydrogen generation via water splitting is crucial. To develop an efficient HER catalyst, Ti, the ninth most abundant metal in Earth’s crust, was engineered systematically. The pristine transition metal titanium cannot drive an electrocatalytic hydrogen evolution reaction (HER) with an efficient rate in an acidic medium (0.5 M H₂SO₄). However, in situ growth of TiO₂ film on Ti surface achieves HER activity, showing an overpotential for 10 mAcm⁻² at 671.4 mV with a Tafel slope of 163.69 mV dec⁻¹. The electrocatalytic performance was further boosted by immobilizing CuO particles onto the as-developed TiO₂/Ti film, which shows 10 mA cm⁻² overpotential at 543.7 mV with a Tafel slope of 101.09 mV dec⁻¹. The CuO–TiO₂/Ti heterostructured electrode exhibited remarkable long-term stability, with the current density increasing by 36% over 25 h of continuous operation, suggesting gradual electrochemical activation while maintaining robust catalytic performance. In this research, detailed structural, surface, and electrochemical investigations, including SEM–EDX, EIS, OCP, and XPS analyses, verified the optimized formation of the TiO₂ layer and CuO incorporation, underscoring the positive impact of heterointerface engineering on HER enhancement. Full article