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Acoustic emission, AE, spectroscopy identifies dislocation avalanches and crack propagation in high-purity Cu with self-stabilized dislocation networks. These samples were produced by additive manufacturing where thermal gradients form cellular structures. These structures confine avalanches of dislocation movements (∼confined dislocations) with an energy exponent ε = 1.82 ± 0.04. Free dislocation movement follows force-integrated mean-field behavior with ε = 1.6 ± 0.02. Additional crack propagation under tension exhibits a critical failure exponent of ε = 1.45 ± 0.01. These three mechanisms combine to generate sample failure under tension. We use this example to demonstrate how different avalanche mechanisms can be disentangled in AE spectroscopy of additive manufactured metal and how the specific self-stabilized dislocation networks influence these avalanche dynamics. [ABSTRACT FROM AUTHOR]

Diabetes-related skin ulcers are of significant clinical concern. Although conventional dressings have been developed, their outcomes have not been adequate, indicating the need to investigate functional dressings for the treatment of diabetic ulcers. Copper selenide nanoparticles (Cu 2 Se NPs) demonstrate outstanding photoresponsiveness, which is critical to the healing process. However, their limited solubility in water restricts their application. To synthesize the ODT-PMMA@Cu 2 Se NP-doped decellularized periosteum‑sodium alginate functional dressing-ODT-PMMA@Cu 2 Se/ECM-S (OP@Cu 2 Se/ECM-S), Cu 2 Se NPs were modified by n-octadecanethiol (ODT) end-functionalized poly (methacrylic acid) (PMAA) ligands homogeneously dispersed in a decellularized periosteum/sodium alginate matrix. This process improved the water solubility and stability. Moreover, under near-infrared irradiation (NIR), ODT-PMMA@Cu 2 Se demonstrated robust photo-responsiveness along with photothermal and photodynamic effects, leading to rapid heating and stimulation of reactive oxygen species (ROS) generation. These two processes work in concert to exhibit excellent antibacterial ability; at 20 μg/mL concentration of Cu 2 Se NPs, the bacterial activities of S. aureus and E. coli were 5.40 % and 0.96 %, respectively. Without the NIR laser irradiation, OP@Cu 2 Se/ECM-S rapidly increased the vascular endothelial growth factor (VEGF) expression, triggered the phosphatidylinositide 3-kinases (PI3K) and protein kinase B (AKT) signaling pathway, affected the expression of bFGF and CD31, and promoted neovascularization, proliferation, and cell migration. In a diabetic mouse wound model, OP@Cu 2 Se/ECM-S exhibited good biocompatibility and promoted epidermal regeneration, collagen deposition, and neovascularization. In a mouse model of subcutaneous abscesses, OP@Cu 2 Se/ECM-S also showed excellent antibacterial activity, in vivo experiments confirmed a decrease in bacterial activity to 1.97 %. Thus, OP@Cu 2 Se/ECM-S is a potentially useful approach for healing diabetic wounds. • Its strong biological activity and superior antibacterial properties are crucial for the healing of diabetic wounds. • The misuse of antibiotics combined with the drawbacks of nanoparticles causes a rise in both cytotoxicity and cell resistance. • A multifunctional dressing that is photoresponsive and free of antibiotics was prepared in this research. Its superior antibacterial and healing properties in vitro and investigated the underlying mechanisms. • Cu 2 Se NPs were functionalized with ODT-PMMA ligands for the first time, distributing them uniformly in the decellularized periosteum/sodium alginate, and exhibiting full healing of diabetic wounds and hair follicle regeneration without the need for near-infrared light. • Moreover, OP@Cu 2 Se/ECM-S has powerful antibacterial properties in the presence of NIR, virtually eliminating microorganisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu modification to VO x /Silicalite-1 for PDH-CO 2. • Improved dispersion of VO x and tuned acidic/basic sites. • Promoted reverse water gas shift. • Highest conversion of propane/CO 2 on 0.5Cu-10VO x /S-1. Propane dehydrogenation in CO 2 atmosphere (PDH-CO 2) is of interest with a potential to raise propane conversion. Here the catalytic performance of Cu modified 10VO x /Silicalite-1(S-1) for PDH-CO 2 is presented for the first time. The initial propane conversion of 68.8% on 0.5Cu-10VO x /S-1 was reached from 59.3% on 10VO x /S-1, along with the CO 2 conversion of 44.5% from 32.4%. The role of S-1 support and Cu modification were elucidated by means of X-ray diffraction (XRD), ultraviolet–visible diffuse reflection (UV–Vis), NH 3 /CO 2 temperature-programmed desorption (NH 3 /CO 2 -TPD), H 2 temperature-programmed reduction (H 2 -TPR) and X-ray photoelectron spectroscopy (XPS) characterization. While dispersing VO x , non-acidic S-1 minimized the side reactions usually occurring on the strong acidic sites. Cu modification promoted the dispersion of VO x and enabled 10VO x /S-1 exposing more weak acidic sites and basic sites, boosting respectively the adsorption of propane and CO 2 , for concurrently accelerating the reverse water gas shift (RWGS). Moreover, the highly dispersed V5+ was formed on the surface whereas the percentage of inactive V3+ decreased. [ABSTRACT FROM AUTHOR]

• Hybrid Ag-TiO 2 /water nanofluid in a copper porous nanochannel via MD. • Investigation of interaction energy, thermal conductivity, and heat flux values. • Effects of different atomic ratios of nanoparticles (1, 2, 3, 5 and 10%) were evaluated. Nanofluids have gained significant attention due to their improved heat transfer capability compared to traditional fluids, making them promising for various applications. Adding nanoparticles to the base fluid alters its thermophysical attributes, such as thermal conductivity, viscosity, and heat transfer characteristics. Understanding the thermal behavior of hybrid nanofluids in porous nanochannels is crucial for optimizing their performance in practical applications. Therefore, this research uses molecular dynamic simulation to evaluate the thermal performance of an Ag-TiO 2 /water hybrid nanofluid combined with a copper porous nanochannel. The changes in parameters such as interaction energy, thermal conductivity, and heat flux were evaluated with time. Also, the effects of different atomic ratios of nanoparticles (1, 2, 3, 5 and 10 %) on mentioned thermal parameters were evaluated. Based on the findings obtained from the molecular dynamics simulation, with the passage of 10 ns, the interaction energy, thermal conductivity, and heat flux values have converged to 1.356 kcal/mol.atom, 1.717 W/m.k and 114.09 W/m2, respectively. Also, by increasing the atomic ratio of added nanoparticles to 3 %, the thermal conductivity and heat flux values have increased to numerical values of 1.83 W/m.k and 126.84 W/m2. After that, by increasing the atomic ratio of nanoparticles to 10 %, the mentioned parameters reach numerical values of 1.79 W/m.k and 120.05 W/m2. [ABSTRACT FROM AUTHOR]

Large volume changes of lithium-ion batteries during battery operation affect battery lifetime and performance through mechanical degradation. Therefore, understanding the coupling between mechanics and electrochemistry in these systems is crucial. In this work, we use neutron diffraction to learn how commercial lithium-ion pouch cells are affected by stack pressure during charge and discharge. We find that a change in stack pressure affects the phase transitions in electrode materials, requiring more charge to reach higher state-of-charge phases which results in effective capacity loss for the battery. Also noteworthy is that the copper current collector experiences strain during charge and discharge due to the expansion of the graphite anode, something often overlooked in these systems. • Neutron diffraction reveals how stack pressure affects charging lithium-ion cells. • Lithium-ion pouch cells lose capacity when charged under applied stress. • Copper current collector experiences significant strain during charge cycling. • Electrode phase transitions require more charge under higher stack pressures. [ABSTRACT FROM AUTHOR]

It is still a controversial issue that whether ductility of metals under high strain rates is varying or not. This paper presents results of a series of electromagnetic ring expansion experiments to study on this problem. Three types of probes were used to measure experimental signals. As a result, the strain at the fracture time can be acquired through in-situ diagnosis. It is found that for a typical metal material, i.e. Cu TU1 under strain rates between 1 × 1 0 3 and 9 × 1 0 3 s−1, the ductility is varying and the fracture strain increases monotonically. These results are new solid evidence of rate-dependent ductility of metals. • The strain at the fracture time can be acquired through in-situ diagnosis. • Through introducing B-dot probes, together with a Rogowski probe and PDV (photonic Doppler velocimetry) probes, more experiment data (current, voltage and velocity signals) is acquired. • Results in this paper offer solid evidence for rate-dependent ductility of the selected metal. [ABSTRACT FROM AUTHOR]

Motivated by the effect of symmetry breaking in cuprates superconductors YBa 2 Cu 3 O 7 - δ , we employ the renormalized mean-field theory to study the presence of uniform superconducting and charge-ordered states in two anisotropic t–J–U models, either with hopping strength anisotropy or antiferromagnetic interaction anisotropy. In the case of uniform superconducting state, compared with the isotropic t–J–U model with only d x 2 - y 2 -wave superconducting state, there is an additional s-wave superconducting state in the model with hopping strength anisotropy. Meanwhile, the hopping anisotropy may enhance the critical Coulomb interaction U c at the Mott insulator to the Gossamer superconductor transition point, and strong hopping anisotropy may weaken the superconducting state. In the case of a charge-ordered state, hopping anisotropy may suppress the amplitude of the charge density waves and pair density waves, which originate from local Coulomb interactions. These results indicate that the effects of hopping anisotropy and local Coulomb interactions are competitive. Moreover, the antiferromagnetic interaction anisotropy only weakly suppresses the superconducting gap and density wave amplitude. Our results show that the t–J–U model with hopping anisotropy is qualitatively consistent with experimental superconducting pair symmetry and charge density waves in the YBa 2 Cu 3 O 7 - δ system. [ABSTRACT FROM AUTHOR]

A new catalytic transfer hydrogenation (CTH) strategy was developed for the continuous conversion of furfural (FF) into furfuryl alcohol (FFA) with Cu/ZnO/Al2O3 (CZA) as the catalyst under mild conditions. Methanediol was used as the hydrogen donor without any hazardous gas emission. FF was converted into FFA with up to 99% selectivity at 108 °C and normal pressure under an N2 atmosphere. The highly dispersive copper species (Cu0, Cu+) with few Lewis acidic sites and η1(O)-type adsorption ensured high selectivity and mild conversion. Deuterium-labelling experiments revealed that, in the presence of formaldehyde, water is split into hydrogen species, which can reduce FF to form FFA. A reasonable reaction mechanism for the conversion of FF into FFA via transfer hydrogenation was proposed. Notably, this strategy offers a new route to splitting water to generate in situ "green hydrogen" for the hydrogenation of unsaturated organic compounds under mild conditions based on non-noble heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

This study details the rational design and synthesis of Cu2ZnSnS4 (CZTS)-doped anatase (A) heterostructures, utilizing earth-abundant elements to enhance the efficiency of solar-driven water splitting. A one-step hydrothermal method was employed to fabricate a series of CZTS–A heterojunctions. As the concentration of titanium dioxide (TiO2) varied, the morphology of CZTS shifted from floral patterns to sheet-like structures. The resulting CZTS–A heterostructures underwent comprehensive characterization through photoelectrochemical response assessments, optical measurements, and electrochemical impedance spectroscopy analyses. Detailed photoelectrochemical (PEC) investigations demonstrated notable enhancements in photocurrent density and incident photon-to-electron conversion efficiency (IPCE). Compared to pure anatase electrodes, the optimized CZTS–A heterostructures exhibited a seven-fold increase in photocurrent density and reached a hydrogen production efficiency of 1.1%. Additionally, the maximum H2 production rate from these heterostructures was 11-times greater than that of pure anatase and 250-times higher than the original CZTS after 2 h of irradiation. These results underscore the enhanced PEC performance of CZTS–A heterostructures, highlighting their potential as highly efficient materials for solar water splitting. Integrating Cu2ZnSnS4 nanoparticles (NPs) within TiO2 (anatase) heterostructures implied new avenues for developing earth-abundant and cost-effective photocatalytic systems for renewable energy applications. [ABSTRACT FROM AUTHOR]

In situ neutron diffraction experiments have been performed to investigate the deformation mechanisms on CoCrFeNi high entropy alloys (HEAs) with various amounts of doped Cu. Lattice strain evolution and diffraction peak analysis were used to derive the stacking fault probability, stacking fault energy, and dislocation densities. Such diffraction analyses indirectly uncovered that a lower degree of Cu doping retained the twinning behavior in undoped CoCrFeNi HEAs, while increasing the Cu content increased the Cu clusterings which suppressed twinning and exhibited prominent dislocation strengthening. These results agree with direct observations by transmission electron microscopy. [ABSTRACT FROM AUTHOR]

Dusts from furnaces for pyrometallurgical refining of copper (Cu) in which arsenic (As) was pre-removed through the use of vacuum carbothermal reduction methods could be used as raw materials. After treating the As pre-removed dusts through oxidative leaching using waste acids, the process of neutralizing and precipitating As and iron (Fe) in the leaching solution was investigated, as well as the precipitation and stabilization process of As and Fe residues. The results show that the leaching rate of Cu, Zn, and As from such dusts can reach 98.98%, 97.46%, and 95.22%, respectively, after leaching operation with waste acids under a liquid–solid ratio of 8:1, a leaching temperature of 80°C, an airflow rate of 300 ml/min, and a leaching time of 120 min. When the molar ratio of Fe to As (n(Fe)/n(As)) is 1.50 in the solution after advanced oxidization, and the final pH value of neutralization is 2.0, the precipitation rate of As and Cu in the residues as ferric arsenates is 93.65% and 2.2%, respectively. As and Fe are neutralized and precipitated, which allows Cu to enter the solution, while As enters the residues. After being transformed, the unstable As and Fe residues can be stockpiled as nontoxic, stable waste. [ABSTRACT FROM AUTHOR]

The synthesized core–shell coordination s-Fe0@Cu-Pd trimetal catalyst could effectively activate room-temperature dissolved ambient oxygen and realized synergistic catalytic degradation of composite pollutants including TC and PNP. [Display omitted] • s-Fe0@Cu-Pd trimetal was synthesized via a step displacement plating process. • s-Fe0@Cu-Pd trimetal sample had the strongest oxidation and reduction ability. • s-Fe0@Cu-Pd trimetal sample presented the strongest O 2 activation ability. • There was a synergistic catalysis effect for wrapped Cu and Pd on s-Fe0@Cu-Pd. Room-temperature ambient air is cheap and easy to obtain, hence the application of room-temperature ambient air as sole oxidant for pollutant degradation is extremely fascinating. In this work, core–shell coordination sponge-Fe0@Cu-Pd trimetal catalyst was synthesized via a simple step displacement plating process employing first displacement of Cu and the subsequent displacement of Pd, and applied as heterogeneous catalyst for synergistic catalytic degradation of composite pollutants including TC and PNP. The prepared s-Fe0@Cu-Pd trimetal sample was characterized with XRD, SEM, TEM, VSM and XPS. The characterization results revealed the obtained s-Fe0@Cu-Pd trimetal sample was a 20 ∼ 30 nm core–shell spherical morphology composed of Fe0 aggregates core wrapped by a Cu-Pd shell layer. The obtained sponge-Fe0@Cu-Pd trimetal catalyst could efficiently activate room-temperature dissolved ambient oxygen and achieve the largest TC removal rate of 99.08 % and PNP removal rate of 97.16 % as well as the biggest removal rate constant of 8.76 min−1 for TC degradation and 7.55 min−1 for PNP degradation within 60 min at experimental conditions: [TC] = 30 mg/L, [PNP] = 30 mg/L, [Catalyst] = 25.52 g/L, pH = 3, 298 K ascribed to the strongest oxidation and reduction ability confirmed by CV characterizations, the lowest charge transfer and contact resistance affirmed by EIS measurements, the strongest O 2 activation ability verified by O 2 -TPD characterizations and DFT analyses, the largest external surface area and mesoporous volume validated by Nitrogen adsorption and desorption characterizations as well as the synergistic catalysis effect for wrapped Cu and Pd. Quenching experiments and EPR characterizations revealed that •OH, •O 2 −, 1O 2 and •H are all the reactive species and meanwhile •O 2 − served as the main reactive oxygen species. Furthermore, possible mechanisms of TC and PNP degradation via sponge-Fe0@Cu-Pd trimetal catalyst were proposed. [ABSTRACT FROM AUTHOR]