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The Al-Mg-Si alloy plate produced by traditional hot rolling has many defects such as complicated processes， long time and high cost， which seriously restricts the development of Al-Mg-Si alloy. Therefore， the Al-Mg-Si alloy plate produced by the twin-rolling casting process has attracted great attention in recent years. The twin-rolling casting process was used to prepare the Al-Mg-Si aluminum alloy plate， and the difference of microstructure at different positions of the plate and the influence on the performance were investigated. The results show that the grain morphology of the edge and the center of the plate is significantly different， the texture composition is complex， a large number of second phases are unevenly distributed along the grain boundary， and there is obvious element segregation inside the plate. According to the theoretical calculation， the contribution strength of texture strengthening at the edges of the twin-rolling casting plate is 10.7 MPa and the contribution strength of grain boundary strengthening is 86.8 MPa， while the contribution strength of texture strengthening in the center of the twin-rolling casting plate is 15.1 MPa and the contribution strength of grain boundary strengthening is 82.4 MPa. The contribution of plate texture and random texture to the strength is limited， and the strength difference between edge and center mainly depends on the grain boundary strengthening. Different degrees of dislocation tangles exist at the edge and the center， and the dislocation density at the edge is higher than that at the center， which is consistent with the statistical results of low angle grain boundaries. According to the characteristics of microstructure inhomogeneity of the plate， the theoretical guidance for the subsequent heat treatment system of the plate is provided through thermodynamic calculation.

In order to study the changes in the content, type of the refractory phases and grain size during homogenization of the 5083 aluminum alloy, material microstructure was characterized by metallographic microscope (OM), scanning electron microscope(SEM), energy dispersive spectrometer(EDS), differential scanning calorimetry (DSC) and X-ray diffractometer (XRD). The results show that the refractory phases in the cast 5083 aluminum alloy are composed of Al(FeMnCr) phases, Al(FeMnCr)Si phases and Mg2Si phases. The composition of the cast state alloy was verified by using phase diagram calculations, and the results are basically consistent with the experiment. As the temperature rises from 460 ℃ to 560 ℃, the electrical conductivity increases firstly and then decreases. This is related to the precipitation of dispersed phase and the dissolution of refractory phase in the structure. When the homogenization processing is 540 ℃/10 h and 560 ℃/10 h, the refractory phase is dominated by the needle-flake Al(FeMnCr) phases, Mg2Si phases is fully solubilized, the area fractions are 0.730% and 0.632%, respectively, and there is no over burned tissue at the same time, and there are obvious dispersed phase particles in the grain. Therefore, to dissolve part of the refractory phases in cast 5083 aluminum alloy, the homogenization temperature must be ≥540 ℃. Increasing homogenization temperature and prolonging homogenization time will increase grain size.When the homogenization temperature is less than 540 ℃, the insoluble phase changes have little effect on the grain growth, when the homogenization temperature is greater than 540 ℃, the average grain size begins to be greater than 140 μm, and the refractory phase is dissolved at the same time.

Designing and synthesizing cathode materials with high specific capacity and stability for aqueous zinc ion battery remains a significant challenge. In this study, citric acid was selected as the reducing agent for converting V2O5 to VO2 with a carbon matrix using the hydrothermal method. The introduction of citric acid not only created a distinct microstructure in V4+ materials but also provided carbon matrix, which resulted in a fast diffusion of zinc ion and a good conductivity. This carbon containing vanadium-oxide material exhibited excellent electrochemical performance as a cathode material for aqueous zinc ion batteries, showing a high specific capacity of 399.33 mAh g−1 at 1 A g−1, and a capacity retention rate up to 98.3% after cycling for 1000 cycles at a high current density of 5 A g−1. [ABSTRACT FROM AUTHOR]

For this article, hot compression tests were carried out on homogenized 2050 Al-Cu-Li alloys under different deformation temperatures and strain rates, and an Arrhenius-type constitutive model with strain compensation was established to accurately describe the alloy flow behavior. Furthermore, thermal processing maps were created and the deformation mechanisms in different working regions were revealed by microstructural characterization. The results showed that most of the deformed grains orientated toward <101>//CD (CD: compression direction) during the hot compression process, and, together with some dynamic recovery (DRV), dynamic recrystallization (DRX) occurred. The appearance of large-scale DRX grains at low temperatures rather than in high-temperature conditions is related to the particle-stimulated nucleation mechanism, due to the dynamic precipitation that occurs during the deformation process. The hot-working diagrams with a true strain of 0.8 indicated that the high strain-rate regions C (300 °C–400 °C, 0.1–1 s−1) and D (440 °C–500 °C, 0.1–1 s−1) are unfavorable for the processing of 2050 Al-Li alloys, owing to the flow instability caused by local deformation banding, microcracks, and micro-voids. The optimum processing region was considered to be 430 °C–500 °C and 0.1 s−1–0.001 s−1, with a dissipation efficiency of more than 30%, dominated by DRV and DRX; the DRX mechanisms are DDRX and CDRX. [ABSTRACT FROM AUTHOR]

In recent years, the in situ resource utilization of CO 2 in the Martian atmosphere by low-temperature plasma technology has garnered significant attention. However, numerical simulation is extremely time-consuming for modeling the complex CO 2 plasma, involving tens of species and hundreds of reactions, especially under Martian pressure. In this study, a deep neural network (DNN) with multiple hidden layers is introduced to investigate the CO 2 conversion in radio-frequency (RF) discharges at a given power density under Martian pressure in almost real time. After training on the dataset obtained from the fluid model or experimental measurements, the DNN shows the ability to accurately and efficiently predict the various discharge characteristics and plasma chemistry of RF CO 2 discharge even in seconds. Compared with conventional fluid models, the computational efficiency of the DNN is improved by nearly 10 6 times; thus, a real-time calculation of RF CO 2 discharge can almost be achieved. The DNN can provide an enormous amount of data to enhance the simulation results due to the very high computational efficiency. The numerical data also suggest that the CO 2 conversion increases with driving frequency at a fixed power density. This study shows the ability of the DNN-based approach to investigate CO 2 conversion in RF discharges for various applications, providing a promising tool for the modeling of complex non-thermal plasmas. [ABSTRACT FROM AUTHOR]

The aging processes of microplastics (MPs) are prevalent in natural environments. Understanding the aging mechanisms of MPs is crucial for assessing their environmental behavior and potential risks. In this study, we selected polylactic acid (PLA) and polyethylene (PE) as representatives of biodegradable and conventional plastics, respectively, to examine changes in their physicochemical properties induced by water and UV light exposure. Laboratory aging resulted in significant fragmentation, characterized by cracks and pores on the surfaces, for both types of MPs, with PLA MPs exhibiting more severe changes, particularly under combined UV and water exposure. Notably, PLA MPs tended to become progressively smaller after aging, whereas PE MPs did not show significant size changes. Chemical analyses of aged MPs using micro-Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed a substantial increase in the carbonyl index (CI) and oxygen content for PE, suggesting surface oxidation during photo-oxidation. Conversely, PLA MPs displayed a CI decrease, along with an oxygen content increase, indicating the breakdown of ester linkages in PLA and the formation of other oxidation products. Furthermore, we developed and optimized pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) methods to identify potential chemical degradation products of PE and PLA, considering their differing thermal stabilities. We observed a distinct trend regarding the peaks in the chromatogram of aged MPs and identified the typical oxidation and crosslinking products for PLA. Additionally, after the aging process, both PE and PLA exhibited a significant increase in organic carbon content, with the eluate containing submicron/nano-sized particles. This study provides a scientific foundation for a deeper understanding of the environmental aging mechanisms of various MPs, particularly in regards to the effects of UV irradiation and water exposure. [ABSTRACT FROM AUTHOR]

In this paper, we propose a full-Stokes image reconstruction (FIR) network to reconstruct polarization images from a snapshot of random modulated image. The Stokes-Mueller matrix theory demonstrates that a image captured by conventional polarization imaging system is a linear superposition of the four Stokes vectors, thus image decomposition methods can be used for full-Stokes image reconstruction. The network is constructed based on a cycled conditional adversarial network, which is trained utilizing the physical mapping relationships between the Stokes vectors and the modulated images. Simulations and experiments are conducted to demonstrate the network's wavelength independence and modulation independence, proving the effectiveness of proposed FIRnet. To some extent, our method alleviates the contradiction between measurement time and accuracy of polarization, promoting the application of compact snapshot full-Stokes imaging. [ABSTRACT FROM AUTHOR]

In this paper, by using the Yamada-Watanabe approximation, the well-posedness for one-dimensional path dependent SDEs with $ \alpha $($ \alpha\geq \frac{1}{2} $)-Hölder continuous diffusion is investigated, which together with the Banach fixed point theorem derives the well-posedness for the corresponding path dependent McKean-Vlasov SDEs. Moreover, the well-posedness for the interacting particle system is also obtained. Finally, the associated quantitative propagation of chaos in the sense of Wasserstein distance is studied, which combined with the Girsanov's transform yields the quantitative propagation of chaos in total variation distance as well as relative entropy. [ABSTRACT FROM AUTHOR]