绿色木塑模板性能及箱形结构优化分析

结合挤出成型法将废旧聚乙烯(WPE)、废旧聚丙烯(WPP)和废弃木粉(WF)分别制成WPE基、WPP基木塑复合材料(WPC)。在获取其用作建筑模板基本物理力学性能的基础上,运用有限元软件对纵向两端简支、不同支撑跨度(S,分别为0.5,0.6,0.7 m)的WPE基、WPP基箱形WPC模板进一步结构优化分析。结果表明,S相同时,WPP基WPC模板比WPE基WPC模板体积用量(V)要少,且随着S的增大,相比WPP基,WPE基WPC模板的V增幅变大,S为0.7 m时最大增幅多达15%。当S为0.5 m时,WPP基WPC模板的V最小;但进一步经济性分析表明,WPP基比WPE基WPC模板单位面积成本高26.0%,所以最佳结构优化方案为S为0.5 m时的WPE基WPC模板,在保证WPC模板力学强度的同时,实现了较好的经济效益。     

Editorial:Special issue on solar radiation measurement

<正>Solar energy is the electromagnetic energy emitted by the sun,w hich is the dominant energy driving the Earth’s climate system[1-2],the radiation fluxes to a...     

Nanometric polishing of lutetium oxide by plasma-assisted etching

Plasma-assisted etching, in which the irradiation of hydrogen plasma and inorganic acid etching are integrated, is proposed as a novel polishing method for sesquioxide crystals. By means of this approach, low damage and even damage-free surfaces with a high material removal rate can be achieved in lutetium oxide surface finishing. Analysis of transmission electron microscopy and X-ray photoelectron spectroscopy reveal that plasma hydrogenation converts the sesquioxide into hydroxide, which leads a high efficient way to polish the surfaces. The influences of process conditions on the etching boundary and surface roughness are also qualitatively investigated using scanning electron microscope and white light interferometry. The newly developed process is verified by a systematic experiment.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-020-00324-z     

Microstructures and Nb-Rich Precipitation Behaviors of Inconel 718 Superalloy Under Sub-rapid Solidification Process

Metallurgical and Materials Transactions A - The sub-rapid solidification behaviors of Inconel 718 superalloy with a novel droplet solidification technique were investigated by analyzing the heat...     

Hierarchically 3D Fibrous Electrode for High-Performance Flexible AC-Line Filtering in Fluctuating Energy Harvesters

In light of the rapid development of intelligence and miniaturization in electronics, the growing demand for sustainable energy sources gives rise to a plethora of environmental/mechanical energy harvesters. However, the fluctuating nature of these generated energies frequently presents a challenge to their immediate usability. Although electrolytic capacitors can smooth fluctuating energy, lacking miniaturization and flexibility constrain their potential applications. Conversely, electrochemical capacitors (ECs), particularly fiber-shaped electrochemical capacitors (FSECs), can offer superior flexibility. Nevertheless, the inherent trade-off between ion transport and charge storage in fibrous electrodes poses a significant obstacle to their filtering capability. Here, a hierarchically 3D fibrous electrode that effectively balances ion transport and charge storage through its unhindered primary framework and intertwined secondary frameworks is presented. The resulting FSEC exhibits an exceptional specific areal capacitance of 1.37 mF cm⁻² with a phase angle of −82° at 120 Hz, surpassing that of fiber-shaped filter capacitors and most non-fibrous filter ECs previously reported. Additionally, the FSEC displays excellent flexibility and high-frequency response, rendering it well-suited for filtering arbitrary ripple voltage and compatible with environmental/mechanical energy harvesters. These results demonstrate a promising approach for designing fibrous high-frequency response electrodes and a foundation for portable environmental energy harvesting devices.     

Multifunctional Cross-Linked Polyurethane Polymer as Interface Layer for Efficient and Stable Perovskite Solar Cells

In the past decade, perovskite solar cells (PSCs) have made remarkable progress in improving power conversion efficiency (PCE). In order to further improve the photovoltaic performance and long-term stability of PSCs, the interface layer is essential. A multifunctional cross-linked polyurethane (CLPU) is designed and synthesized via the spontaneous quaternization of polyurethane and 1, 6-diiodohexane on the surface of the perovskite layer. CLPU layer cannot only effectively induce secondary crystallization and passivate the surface defects of perovskite, reduce the non-radiative recombination, but also effectively block the moisture invasion. By this strategy, Cs_0.05FA_0.95PbI₃ PSCs with excellent reproducibility, is realized, achieving a PCE of 23.14% with an open-circuit voltage of 1.11 V, a short-circuit current density of 25.69 mA cm⁻², and a fill factor of 0.81. In addition, the unencapsulated devices show enhanced stability in 35 ± 5% relative humidity (RH) near 3000 h and in 65 ± 5% RH over 700 h. This study provides valuable insights into the role of CLPU interface layer in PSCs, which are essential for the design of high-performance devices.