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11.
葛琳琳 《辽宁石油化工大学学报》2014,(5):52-56,69
以某球团厂破碎车间的布料过程为背景,针对该厂布料过程中小车定位不准和布料不均匀的问题,提出了基于PLC的模糊控制算法,结合超声波料位计和激光测距仪的反馈信息,有效地解决了该厂布料过程中小车定位不准和布料不均匀的缺点。利用上位机组态画面实现了对布料过程的远程监控,提高了车间的自动化水平,改善了操作人员的工作环境。本系统在运行期间能够准确判断矿仓的物料需求,完成布料小车的精确定位,降低了操作人员的工作强度。 相似文献
12.
车厢式移动空气监测站是一种将空气自动站改造为车厢形式,通过与皮卡车组装,实现其流动监测的功能,是适应于中小城市运用于大气流动监测的技术。文中介绍了车厢式移动空气监测站的改造细节和应用特点。 相似文献
13.
为满足大型热轧机生产铝板带材宽度范围大的要求,设计了助卷宽度范围大的车架互换式双带助卷器。本文介绍为某2850mm热连轧机配套设计的车架互换式双带助卷器的工作原理、结构特点和助卷带张力的计算方法。 相似文献
14.
用静态平衡釜法测定了丙烯-水-甲醇3元物系其中甲醇-水质量比为9∶1、8∶2和7∶3 在30℃~60℃温度、0.3MPa~0.9MPa 压力下的汽液平衡数据,用vanLaar-RK模型方程对汽液平衡数据进行了关联,求得各模型参数,所得结果令人满意。 相似文献
15.
This paper reports the result of an investigation on the axially compressed buckling of multi-walled carbon nanotubes under thermal load, based on a rigorous van der Waals interaction which is dependent on the change of interlayer spacing and the radii of tubes. From the point of view of continuum modeling, each of the concentric tubes of multi-walled carbon nanotubes is considered as an individual elastic shell and coupled with any two tubes through a rigorous van der Waals interaction force. Based on this model, some example calculations are carried out to describe the effect of temperature changes and van der Waals interaction models on the axially critical load of multi-walled carbon nanotubes. Some results obtained show that the axial buckling stress of multi-walled carbon nanotubes under thermal environment is dependent on the wave number of axially buckling modes, and the wave numbers corresponding to the minimum axial stress are not unique for the multi-walled carbon nanotubes under thermal environments. On the other hand, a rigorous van der Waals interaction force can make the axially critical load of multi-walled nanotubes under thermal loading increase. The effect of thermal environments on the axially critical stress of multi-walled nanotubes gradually increases as the axial half wavenumber (m) of buckling modes increases. 相似文献
16.
主要论述了G型沉降片和积极式输线器的主要性能特征,分析了它们对针织生产及针织品性能的影响,说明采用这些针织器材,不但能够提高生产效率,而且能够生产高性能、高品质的针织品。 相似文献
17.
18.
介绍了全圆针梁钢模台车设计要求、台车组成、台车安装.叙述了引子渡水电站引水隧洞钢模台车混凝土衬砌施工工艺,并进行了经济效益分析.可供同类工程施工参考及推广应用. 相似文献
19.
Cosme G. Ayani;Michele Pisarra;Iván M. Ibarburu;Manuela Garnica;Rodolfo Miranda;Fabián Calleja;Fernando Martín;Amadeo L. Vázquez de Parga; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(8):2303275
Kondo lattices are systems with unusual electronic properties that stem from strong electron correlation, typically studied in intermetallic 3D compounds containing lanthanides or actinides. Lowering the dimensionality of the system enhances the role of electron correlations providing a new tuning knob for the search of novel properties in strongly correlated quantum matter. The realization of a 2D Kondo lattice by stacking a single-layer Mott insulator on a metallic surface is reported. The temperature of the system is steadily lowered and by using high-resolution scanning tunneling spectroscopy, the phase transition leading to the Kondo lattice is followed. Above 27 K the interaction between the Mott insulator and the metal is negligible and both keep their original electronic properties intact. Below 27 K the Kondo screening of the localized electrons in the Mott insulator begins and below 11 K the formation of a coherent quantum electronic state extended to the entire sample, i.e., the Kondo lattice, takes place. By means of density functional theory, the electronic properties of the system and its evolution with temperature are explained. The findings contribute to the exploration of unconventional states in 2D correlated materials. 相似文献
20.
Zhaorui Wen;Chao Liang;Shengwen Li;Gang Wang;Bingchen He;Hao Gu;Junpeng Xie;Hui Pan;Zhenhuang Su;Xingyu Gao;Guo Hong;Shi Chen; 《ENERGY & ENVIRONMENTAL MATERIALS》2024,7(4):e12680
Two-dimensional materials have been widely used to tune the growth and energy-level alignment of perovskites. However, their incomplete passivation and chaotic usage amounts are not conducive to the preparation of high-quality perovskite films. Herein, we succeeded in obtaining higher-quality CsPbBr3 films by introducing large-area monolayer graphene as a stable physical overlay on top of TiO2 substrates. Benefiting from the inert and atomic smooth graphene surface, the CsPbBr3 film grown on top by the van der Waal epitaxy has higher crystallinity, improved (100) orientation, and an average domain size of up to 1.22 μm. Meanwhile, a strong downward band bending is observed at the graphene/perovskite interface, improving the electron extraction to the electron transport layers (ETL). As a result, perovskite film grown on graphene has lower photoluminescence (PL) intensity, shorter carrier lifetime, and fewer defects. Finally, a photovoltaic device based on epitaxy CsPbBr3 film is fabricated, exhibiting power conversion efficiency (PCE) of up to 10.64% and stability over 2000 h in the air. 相似文献