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Human activities have liberated substantial amounts of biologically active metals into oceans. However, identifying the sources and migration processes of these metals is challenging. Here we present first century‐long records of concentrations and isotope compositions of Zn and Cu (δ66Zn and δ65Cu) in two corals from the northern South China Sea. The results show dramatic enrichment in coral Zn and Cu concentrations since the 1980s, which coincide with δ66Zn and δ65Cu increases. Coupled with concurrent land use/cover changes, we suggest that the enrichment trends of Cu and Zn in corals are best explained by human‐induced rock weathering and soil erosion, which transferred isotopically heavy Zn and Cu fluxes into the coastal ocean. The metal releases due to land use/cover changes relative to direct anthropogenic sources could be even more significant in the future given that anthropogenic releases have been legally controlled and started to decline in recent decades. Plain Language Summary: Substantial amounts of biologically active but potentially toxic metals such as zinc and copper have been released into the Earth's surface due to increasing human activities. Most previous studies linked marine zinc and copper enrichment to direct human‐related releases that are transferred into oceans via atmospheric deposition and river discharge, but neglected natural releases that have been augmented by human activities. Here, we found that zinc and copper levels in annually banded corals from South China Sea coastal areas are increasing since the early 1980s, and these increasing trends are best explained by human‐induced rock weathering and soil erosion based on evidence from first measured isotope signatures and land use/cover changes. This pathway was largely overlooked before, but might be a predominant pathway accounting for marine metal enrichment in future given more and more strict environmental laws targeted at curbing metal releases by human activities. Key Points: The coral Zn and Cu isotopic compositions indicate progressive changes of Zn and Cu sources into the ocean through the timeUnprecedented enrichment of coastal Zn and Cu since the 1980s is associated with increases in δ66Zn and δ65CuHuman‐induced rock weathering and soil erosion mainly contributed increased fluxes of dissolved Zn and Cu [ABSTRACT FROM AUTHOR]

The properties of Cu(V) alloy films were investigated to evaluate its potential use as self-forming diffusion barrier in copper metallization. Cu(V) alloy films were deposited on SiO 2 /Si substrates by magnetron sputtering. Cu(V)/SiO 2 /Si systems were subsequently annealed at various temperatures and analyzed by four-point probe measurement (FPP), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). After annealed at 500 °C, the resistivity of the Cu(V) films reduced to 3.1 μΩ cm, there is no obvious increase in resistivity. XRD suggest that Cu alloy film has preferential (111) crystal orientation and no extra peak corresponding to Cu and Si even after annealed at 500 °C. According to TEM results, a self-formed thin layer with the thickness of about 8 nm is observed at the interface between Cu alloy and the SiO 2 /Si substrate in the sample annealed at400 °C. As XPS results, after annealed at 400 °C and 500 °C, V atoms are observed at the surface of the Cu(V) films and the interface of the Cu(V) and SiO 2 /Si. The formation of the self-formed thin layer is probably due to the separation of V at the interface. The sharp declines of the Cu and Si concentrations at the interface indicate a lack of inter-diffusion between Cu and SiO 2 /Si. Adding small amounts of V to Cu film can improve the barrier performance and thermal stability compared with pure Cu contact systems. [ABSTRACT FROM AUTHOR]

The nanocrystalline metallic bilayer structure can effectively enhance the strength of Cu alloy while maintaining excellent electrical conductivity. Based on the microstructure evolution of Cu/Ag alloy observed by transmission electron microscope (TEM), molecular dynamics (MD) simulations of Cu/Ag alloy with nanocrystalline metallic bilayer structure were established. The mechanical properties and deformation mechanisms of nanocrystalline Cu/Ag-bilayer alloys were investigated at different temperatures. A mixed Hall-Petch (H-P) relationship was observed between the ultimate stress and the increased layer thickness. In this paper, the deformation mechanism changes from dislocation accumulation at the Cu-Ag interface to dislocation through the Cu-Ag interface. In addition, the data analysis results of elastic modulus showed an approximately linear decrease trend with increasing temperature, and the deformation mechanism shifted from dislocation motion to a combination of dislocation motion and grain boundaries (GBs) diffusion. These findings provide guidance for the design of high magnetic field facility (HMFF) water-cooled magnets and very large-scale integration (VLSI) lead frames. • The deformation behaviour of the nanocrystalline Cu/Ag-bilayer alloy at different thicknesses (4–6 nm) and temperatures (1–800 K) is investigated. • The layer thickness of Cu/Ag-bilayer alloy conforms to the mixed H-P relationship. The mechanism changes from dislocation pile-up. • As temperatures increases, the deformation mechanism transformed from dislocation emission to a combination of dislocation motion and the high-temperature softening. [ABSTRACT FROM AUTHOR]

[Display omitted] • Performance of single crystal copper rod was improved by rare earth microalloying. • The interaction between rare earth Y and impurity P was established by Miedema model. • The precipitation behavior of Y and P was discussed. • The synergistic enhancement of mechanical and conductive properties was proposed. Single-crystal copper rods with high conductivity and mechanical properties are the decisive material for the production of microwires for chip bonding. To further improve the product of strength and elongation as well as electrical conductivity, rare earth Y is added to a single-crystal copper rod to adjust the microstructure and impurity state. The results show that Cu-0.03Y copper rods have excellent comprehensive properties. The electrical conductivity improves to 103.72 % IACS, and the product of strength and elongation improves to 8.772 GPa%. The precipitates in the Cu-0.03Y single crystal copper rod are nano-sized spherical particles composed of YP (NaCl type) and Cu 5 Y (Cu 5 Ca type) phases. The enthalpy of formation of Y and P is calculated using Miedema thermodynamics as ΔH = −173.45 kJ·mol−1. The precipitates formed by the preferential reaction of Y and P reduce the solid dissolved atoms in the copper, and the electrical conductivity increases accordingly. The 〈0 0 1〉 texture of a single-crystal copper rod decreases with the addition of Y, while the 〈1 0 1〉 texture increases with good plasticity, leading to an improvement in elongation. [ABSTRACT FROM AUTHOR]

Abstract: Films of Cu/Cu(Ru) and Cu(Ru) were deposited on Si substrates by magnetron sputtering. Samples were subsequently annealed and analyzed by four-point probe (FPP) measurement, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Auger electron spectroscopy (AES). After annealing at 500°C, resistivity values of both systems decrease, but the reduction is more significant for Cu(Ru). Moreover, the resistivity values of annealed Cu(Ru) film are still greater than those of annealed Cu/Cu(Ru) film. XRD data suggest that Cu/Cu(Ru) film has higher thermal stability and Cu silicide cannot be observed up to 500°C. According to TEM results, after annealing at 500°C, the grain size of the Cu(Ru) film is smaller than that of Cu/Cu(Ru) film. In conjunction with AES, XRD, TEM analyses and sheet resistance measurement, it indicates that Cu/Cu(Ru) seed layers are potentially good for advanced Cu interconnects from the views of interfacial stability and low resistivity. [Copyright &y& Elsevier]