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1.
Terahertz (THz) imaging is expected to become powerful tools for non-destructive inspections. To ensure the practical use of THz non-destructive monitoring, versatile THz imagers with adjustable designs that can eliminate the complexities and the bulkiness of the device are urgently required. Herein, a self-aligned filtration process for a 2D, free-standing carbon nanotube film array and its application to a THz video camera patch are reported. The presented techniques enable a) to freely design the camera size, sensor array pattern, and suspended shape according to its applications, b) to cut the camera patch into desired shapes, and c) to attach them to the objects that are intended to be measured. Real-time, non-destructive monitoring of various infrastructures is demonstrated. These results indicate that it can function regardless of restrictions, such as the shapes and locations of the measurement samples, thus providing a strong possibility for use in future non-destructive sensor networks.  相似文献   
2.
王华民 《水泥》2021,(8):77
我公司2×4?500 t/d熟料生产线于2007年和2008年先后建成投产,2条熟料生产线分别配置1台MLS4531生料立磨和1个Φ18 m×50 m的生料均化库,2010年建成生料互通可逆皮带。经过几年的运行发现,生料倒料过程中容易污染环境,特别是近年来环保检查常态化后,倒料过程中的污染问题成了公司的环保难题,必须进行彻底的防污染改造。为充分利用现有钢廊道及倒料系统设施,节省投资,经认真考虑,2019年12月份我们完成了全密封性的双向充气涌管代替可逆皮带的改造。改造后运行效果良好,既保护了环境又实现了生料互通的目的。  相似文献   
3.
王华民 《水泥》2021,(12):51
利用双轴搅拌机的工作原理设计的石粉和脱硫石膏混合装置,将石粉和脱硫石膏混合成干湿均匀料加入水泥磨,既利用了石粉、节约了石子,又解决了水泥生产过程中脱硫石膏水分大、不便输送和难稳定入磨的问题,效果显著。  相似文献   
4.
Gd2O2S:Tb (GOS) phosphor screen, generally with a multilayer structure, has been widely used in digital X-ray imaging. GOS phosphor screen is fabricated via a slip casting route, which is an effective method to obtain multilayer composites with good strength. The GOS slurry was prepared using the menhaden oil, polyvinyl butyral and PEG-400 as dispersant, binder and plasticizer, respectively, and slip casted on a support layer. After the GOS scintillation layer is formed, a transparent polyethylene terephthalate film is covered on it as a protective layer. The X-ray excited emission spectra of the obtained GOS phosphor screen is well match to the spectral response of a-Si:H photodiode, and the spatial resolution was close to 3.7 LP/mm, which could meet the request of the commercial application.  相似文献   
5.
Journal of Mechanical Science and Technology - Aiming at the problem that the membrane structure is prone to creases in the process of folding and compaction, a proxy model is used to replace the...  相似文献   
6.
Salt spray corrosion test was carried out on 6061 aluminum alloy, and quasi-static tensile test at room temperature was carried out on the sample with universal testing machine. The effect of salt spray corrosion on the mechanical properties of 6061 aluminum alloy was studied by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and electrochemistry. The corrosion rate of 6061 aluminum alloy was quantitatively characterized by different corrosion parameters. It was found that local corrosion of 6061 aluminum alloy occurred in salt spray environment, mainly pitting corrosion and intergranular corrosion. With the increase of corrosion time, the polarization resistance of 6061 aluminum alloy decreases, and the corrosion rate significantly increases. The average corrosion rate and the maximum corrosion rate of 6061 aluminum alloy were characterized by corrosion weight loss and corrosion pit depth. And they can be transformed into each other. The mechanical properties of 6061 aluminum alloy were mainly affected by the depth of corrosion pit. With the increase of corrosion time, the tensile strength and fracture strain decreased, resulting in poor plasticity of the sample. At the same time, the change of elongation of 6061 aluminum alloy can be accurately predicted by the depth of corrosion pit.  相似文献   
7.
ZrC precursor was synthesized by a solution approach using ZrOCl2·8H2O, acetylacetonate, glycerol and boron-modified phenolic resin. A ZrC yield of ~ 40.56 wt% was obtained at 1500 °C in the C/Zr molar ratio of 1:1. C/C-ZrC-SiC composites were fabricated by a combined processes of chemical vapor infiltration (CVI) and precursor infiltration and pyrolysis (PIP) using the synthesized ZrC precursor. For comparison, C/C-SiC composites were prepared by CVI. Thermogravimetric analysis showed that C/C-ZrC-SiC composites exhibited better oxidation resistance than C/C-SiC composites. After oxyacetylene torch ablation, the mass ablation rate of C/C-ZrC-SiC composites was 9.23% lower than that of C/C-SiC composites. The porous ZrO2 skeleton in the ablation center was prone to be peeled off by the flame flow, resulting in the higher linear ablation rate of C/C-ZrC-SiC composites. The oxide layers of ZrO2 and SiO2 were formed on the transition and brim region of C/C-ZrC-SiC composites and acted as effective heat and oxygen barriers. For C/C-SiC composites, the C-SiC matrix was severely depleted in the ablation center and the formed SiO2 layer in the brim region could protect the matrix against further ablation.  相似文献   
8.
Journal of Failure Analysis and Prevention - To investigate the strength and fatigue life of a fracture-split connecting rod, this study combines experiments on connecting rod fracture splitting,...  相似文献   
9.
研究了面铣刀的主偏角对切屑厚度和每齿进给量的影响,铣削中每齿进给量的决定因素,切削宽度与刀具直径的比值对切屑厚度的影响等问题进行理论分析,同时结合变速箱壳体铣削加工过程进行验证,解决了合理选择铣刀及切削参数以提升加工效率的问题。  相似文献   
10.
在电梯平衡系数传统测量方法中,存在电梯轿厢和对重平衡点难以判断、人为因素导致测量误差偏大、测量不准导致效率低等问题,为解决这些问题,设计出一款基于光电传感器和霍尔传感器的电流自动捕捉工具,除能够高效准确识别电梯轿厢和对重平衡点的位置外,还能通过无线信号传输处理,利用钳形电流表精确捕捉平衡点位置的电流值。经测试使用,该工具系统消除了在平衡系数测量过程中捕捉电流值的人为因素影响,并解决了无机房不能准确判断平衡点问题,有效的提高了检验工作的准确性和效率。  相似文献   
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