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Cu-0.85Cr-0.5Zr-0.5Mo in situ composite was prepared by continuous casting, cold drawing, and aging treatment. By means of the analysis of microhardness, electrical conductivity, and transmission electron microscopy, the aging characteristics and microstructures of the in situ composite were investigated at different aging temperatures and aging times after cold deformation. The results show that the Cu-0.85Cr-0.5Zr-0.5Mo in situ composite has an excellent combination of the microhardness and electrical conductivity aged at 500°C for 4 h, and the microhardness and electrical conductivity reach 171 HV and 81.3% IACS, respectively. Small dispersed particles could strongly pin dislocations and stabilize the substructure from deformation. The main strengthening mechanisms for the in situ composite alloy are the work hardening and the secondary phase or interface strengthening. It was suggested that cold deformation before aging treatment can accelerate the precipitation of the secondary phase and improve the comprehensive properties of the Cu-Cr-Zr-Mo in situ composite.

The 0.3%Y2O3/0.3%La2O3/0.3%Al2O3/Cu composite was prepared by oxygen and nitrogen atomization spray deposition technique, internal oxidation, and then treated by annealing at different temperatures. Physical properties such as microstructures, fracture appearance, hardness, strength, electrical conductivity, and arc erosion surface of the composite were investigated. The experimental results show that with an increase in the annealing temperature, the grains of the composite grow up obviously and the electrical conductivity of the composite increases gradually, while the hardness and the tensile strength decrease. When the annealing temperature reaches 1000°C, the matrix grains begin to appear as annealing twins. The tensile fracture morphology of the composite that has been treated by annealing at 700°C for 2 h shows a huge number of large and deep dimples, in which the metallic oxide particles exist. The fracture mode of the composite is the microporous polycondensation plastic fracture. The arc erosion surface shows a large number of paste-like coagulum and bubbles.

An accurate sky polarization field map is a prerequisite for polarization navigation applications. In this article, a detector or sky full-polarization imaging detection is described, the major error-influencing factors (MEIFS) are obtained, and the error propagation is modeled and analyzed. We reveal the relationship between the error of the inversed Stokes vector and the condition number of the detector matrix, which shows that the error of the inversed Stokes vector is affected by the Stokes vector of the incident light itself and the MEIFS together, with the MEIFS playing a decisive role. With the MEIFS optimized, the impact of detector error on the inversed Stokes vector is attenuated. A control equation for system calibration is also deduced which can establish the connection between the detector matrix design and calibration process. The work in this article provides a reference for optimization and calibration of sky full-polarization imaging detectors.

A high alloying degree is required for AgCuNilnSn series electrical contact materials and it is necessary to perform homogenizing heat treatment on the alloy ingot to eliminate non-equilibrium phases with low melting-point and dendritic segregation in the ingot microstructure. The traditional "trial-and- error" method for finding the optimal process parameters for heat treatment has the defects ofhuge number of experiments, long cycle and low efficiency. A high-throughput preparation method for homogenizing heat treatment with gradient temperature field was proposed in this paper to screen the optimal treatment conditions for Ag-6Cu-0.5Ni-0.5In-0.5Sn. The experimental results show the maximum hardness of the alloy obtained after 75% plastic deformation by gradient homogenization heat treatment is 168.7, a value corresponding to the optimum homogenization heat treatment temperature of 608.13 °C/1 h. Under the optimal annealing conditions, the volume of grains and the second phase are small, and the distribution of point-like second phase dispersion is more and uniform. At this point, the strengthening effects both from fine grains and dispersions are most significant. [ABSTRACT FROM AUTHOR]

The first-step drawing process of the platinum-clad nickel composite bar was numerically simulated using DEFORM 3D finite element analysis software. The Taguchi method was used to study the effect of the first-step drawing parameters (the semi-angle of die α, the friction coefficient between the platinum tube and die μ1, the friction coefficient between the platinum tube and nickel rod μ2 and the outer diameter of the original platinum tube D) on the effective stress of platinum-clad nickel bar. Then, the optimal combination of parameters (D = 7.55 mm, μ1 = 0.2, μ2 = 0.3, α = 3°) was obtained. Furthermore, the results of the deformation behavior, cladding behavior, stress effectiveness and the distribution of the damage of the composite bar using optimization schemes were compared and analyzed with Numerical Simulations 8, which showed the worst result. Meanwhile, the experimental results were in general agreement with the simulation results of optimal combination of parameters, indicating that our simulation results are plausible. This has certain guidance significance to improve the quality of platinum-clad nickel composite wires in actual production. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) SnO2 nanostructures, as n-type semiconductors with a wide band gap, exhibit unique photoelectric properties that offer potential applications in electronic, photoelectric, gas sensing, and energy generation devices. A detailed study of template-free reaction systems is essential to regulate and efficiently synthesise 1DSnO2 nanostructures. This study employed the hydrothermal method to prepare 1DSnO2 nanostructures, with SnCl4·5H2O as the tin source. The impact of various experimental conditions on SnO2 morphology is analysed. Here, 1DSnO2 nanostructures were characterised by analytical methods such as X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, and field emission double-beam electron microscopy. The results confirmed the formation of 1DSnO2 nanostructures with a mixed morphology of nanorods and nanowires. The nanorods exhibited a length of 422.87 ± 110.15 nm, a width of 81.4 ± 16.75 nm, and an aspect ratio of 5:1, whereas the nanowires displayed a length of 200 ± 45.24 nm, a width of 15 ± 5.62 nm, and an aspect ratio of 13:1. With the addition of 50 mg of polyvinylpyrrolidone and seed crystal, the acquisition time of the 1DSnO2 nanostructures decreased from 48 to 12 h. The 1DSnO2 nanostructures were efficiently obtained without a template, laying the foundation for large-scale production and application. [ABSTRACT FROM AUTHOR]

Mueller matrix imaging polarimetry (MMIP) is a promising technique for the characterization of biological tissues, including the classification of microstructures in pathological diagnosis. To expand the parameter space of Mueller matrix parameters, we propose new vector parameters (VPs) according to the Mueller matrix polar decomposition method. We measure invasive bladder cancer (IBC) with extensive necrosis and high‐grade ductal carcinoma in situ (DCIS) with MMIP, and the regions of cancer cells and fibrotic stroma are classified with the VPs. Then the proposed and existing VPs are mapped on the Poincaré sphere with 3D visualization, and an indicator of spatial feature is defined based on the minimum enclosing sphere to evaluate the classification capability of the VPs. For both IBC and DCIS, the results show that the proposed VPs exhibit evident contrast between the regions of cancer cells and fibrotic stroma. This study broadens the fundamental Mueller matrix parameters and helps to improve the characterization ability of the MMIP technique. [ABSTRACT FROM AUTHOR]

Mueller matrix imaging polarimetry (MMIP) is a promising technique for the textural characterization of biological tissue structures. To reveal the influence of imaging magnification on the robustness of Mueller matrix parameters (MMPs), the spatial scale stability of MMPs was studied. We established a new MMIP detector and derived the mathematical model of the spatial scale stability of MMPs. The biological tissues with well‐defined structural components were imaged under different magnifications. Then, we compared and analyzed the textural features of the MMPs in the resulting images. The experimental results match the predictions of the mathematical model in these aspects: (a) magnification exhibits a strong nonlinear effect on the textural contrasts of MMPs images; (b) higher magnification does not necessarily lead to superior contrast for textural characterization; and (c) for different biological tissues, MMPs contrasts can be optimized differently, with some showing superior results. This study provides a reference for the experimental design and operation of the MMIP technique and is helpful for improving the characterization ability of MMPs. [ABSTRACT FROM AUTHOR]