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61.
梭车是短壁机械化开采技术的重要运输设备。简要介绍了现有梭车的现状及应用局限,详细阐述了分体梭车的主要设计思路,重点介绍了薄壁分体式机架的结构特征,阐述了分体梭车在模块化卷电缆装置、四象限变频驱动等方面的技术升级,并介绍了分体梭车在国内矿区的应用情况。 相似文献
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随着社会环保意识的增强,大气污染物的排放标准也日益严格,这给环保工程带来了极大的潜在市场。脱硝反应器设计作为SCR脱硝工艺中除了催化剂的另一核心,在水泥行业没有更好的催化剂被研发出来之前,想要脱硝设备的性能得到极佳的发挥,在高温高尘区布置除尘+脱硝设备已经是工程上的一个选择,而在高尘区要保证催化剂的稳定、高效运行,流场的优化必不可少。本文针对某水泥行业除尘+脱硝项目,采用CFD软件对其流场进行数值模拟,并给出导流板的优化设计方案。结果表明:在电除尘器上进气口布置合适的导流板,使得进入电场的烟气分布均匀;同时在整流格栅前添加导流板,脱硝反应器内的流场也得到了极大改善。因此,采用CFD软件数值模拟对水泥行业除尘+脱硝有着重要的意义。 相似文献
64.
Formation of capillary vessel structures in scaffolds is critical for engineering various tissues and organs. Various biofabrication techniques are developed in recent years to create scaffolds integrated with perfusion channels. However, rapid fabrication of artificial capillary vessels (<10 µm) still remains challenging. In this study, a novel electrospinning approach is developed to fabricate nanoporous polycaprolactone microtubes as potential functional capillaries. The results show that ambient environment parameters and solution properties affect the pore formation and tube morphology. Porous microbeads, helical fibers, and microtubes were fabricated under different processing conditions. The optimal tubular structure is obtained with consistent viscosities between the core and the sheath solutions. The biomimetic nanoporous microtubes hold great potential for vascularization in tissue engineering. 相似文献
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Herein, we report integrated photo-rechargeable supercapacitors (IPSs) composed of the inverted organic solar cell (iOSC) and solid-state supercapacitor (SC), enabling a high-performance self-power pack. The iOSC serves as a self-power source while the SC functions as energy storage, and both share an indium-tin-oxide (ITO) electrode that affords improved charge propagation across the devices. Combining the energy harvesting and storage devices in this way significantly alleviates the limitations of each device. The power fluctuation of the iOSC can be reimbursed by the SC, thus allowing for a stable energy output. Moreover, the SC is frequently charged by the iOSC during the daytime, thereby greatly reducing the charging time and avoiding a complete discharge as well. When the SC of the IPS is charged by the iOSC under AM 1.5 G of illumination, the overall energy conversion-storage efficiency is ca. 2.27%. Our work provides an effective strategy for further study to fabricate a small, lightweight, portable/wearable self-power pack by integrating energy harvesting and energy storage devices into a single structure. 相似文献
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This study aims to examine the practicality of a novel passive heat transport system “thermosyphon heat transport device” (THTD). It is a fluid-filled unit, with both source and sink amalgamated within it. A vertical tube-in-tube design has been incorporated, consisting of heat source, adiabatic height, and sink. To showcase the performance, a transient numerical analysis is performed using ANSYS Fluent, which is compared with the simple closed thermosiphon (SCT) for heat transport capability (1 kW) and different adiabatic heights (0.25, 1, and 1.5 m). Also, the influence of axial conduction is examined. The proposed Therminol VP1-based THTD has better heat transport capability over SCT due to a uniform flow pattern. Although the time response diminishes with adiabatic height, the novelty is justified as the heat gained by THTD (adiabatic height: 1.5 m) is 1.5 times more than SCT. Furthermore, the THTD performance is experimentally analyzed by varying the coolant flow rate (0.01, 0.02, and 0.03 kg/s), heat load (100−600 W), and transport distance (0.25 and 0.75 m), which yielded 80%−90% energy efficiency. As the THTD is crucial for a conceptual solar indoor cooker, the response under transient heating/cooling conditions is also investigated, which depicted 300 s for transient heating and 10−50 s for transient cooling. 相似文献
70.
Hyun-Ju Choi Jong-Un Woo Hyun-Gyu Hwang Dae-Su Kim Mohan Sanghadasa Sahn Nahm 《Journal of the European Ceramic Society》2021,41(4):2559-2567
Li2O/B2O3-added Ba1-xSrxTiO3 (B1-xSxT) ceramics, where 0.2 ≤ x ≤ 0.35, were well densified at 920 °C with pure perovskite structure. The dielectric constant, tunability, and figure of merit (FOM) of B1-xSxT ceramics increased with x because of the decreasing Curie temperature (TC). The specimen with x = 0.35, whose TC was close to room temperature, exhibited a large tunability of 27.4 % and FOM of 110 at 10 kV/cm. A compositionally graded multilayer (CGML), which was sintered at 920 °C, was fabricated using B1-xSxT thick films to produce a temperature-stable tunable capacitor, and it evinced a dense microstructure and a continuous interface between the B1-xSxT thick film and the Ag electrode. This CGML capacitor showed a large tunability (51 %) and FOM (150) at 20 kV/cm. It also exhibited stable tunability (17–28 % at 10 kV/cm) at temperatures between 30–90 °C. Therefore, the B1-xSxT CGML capacitor is a suitable candidate for temperature-stable tunable capacitors. 相似文献