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61.
The copper and cobalt oxides composites coatings on aluminum substrates have been successfully synthesized via sol-gel method using nitrate-based sol precursors. The composites were characterized by X-ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), and UV–Vis–NIR spectrophotometry. The sol-gel reactions were discussed and Molecular Dynamics (MD) simulation was integrated into the study to predict molecules assembly properties. The XRD analyses revealed that the CuO and the Co3O4 composites were formed after the annealing process with the average difference of the calculated lattice parameters compared to ICDDs was 1.17%. The surface electronic structure was mainly consisted of tetrahedral Cu(I), octahedral Cu(II), tetrahedral Co(II), octahedral Co(III) as well as surface, sub-surface and lattice oxygen O?. The XRD, XPS and MD simulation results showed that there was minimal (or possibly non-existing) indication of copper-cobalt mixed phase oxides formations. FESEM and AFM surveys revealed that the coating had a porous surface composed of interlinked nanoparticles in the range of ~?10 to ~?40?nm. UV–Vis–NIR reflectance spectra showed that the sol precursors concentration and the dip-drying cycle significantly influenced the absorptance value with optimum absorptance (α) of 88.7% exhibited by coating synthesized using sol concentration of 0.1?M and 10 dip-drying cycles. High absorptance value and simplicity in the synthesis process render the coatings to be very promising candidates for solar selective absorber (SSA) applications.  相似文献   
62.
Structural and Multidisciplinary Optimization - The overall layout optimization design of an orbital propellant depot involves the optimization of shape, size, and positions of propellant tanks in...  相似文献   
63.
Single image super resolution (SISR) is an important research content in the field of computer vision and image processing. With the rapid development of deep neural networks, different image super-resolution models have emerged. Compared to some traditional SISR methods, deep learning-based methods can complete the superresolution tasks through a single image. In addition, compared with the SISR methods using traditional convolutional neural networks, SISR based on generative adversarial networks (GAN) has achieved the most advanced visual performance. In this review, we first explore the challenges faced by SISR and introduce some common datasets and evaluation metrics. Then, we review the improved network structures and loss functions of GAN-based perceptual SISR. Subsequently, the advantages and disadvantages of different networks are analyzed by multiple comparative experiments. Finally, we summarize the paper and look forward to the future development trends of GAN-based perceptual SISR.  相似文献   
64.
The corrosion behavior of synthetic Cu–Sn bronze alloys with six different Sn contents was examined through an electrochemical test and a synthetic test in a simulated corrosive medium. The mechanism of corrosion and the morphology of the corroded surfaces were characterized through field emission scanning electron microscopy equipped with energy-dispersive spectroscopy. At the corrosion potential, the corrosion behavior appears to be determined by the charge transfer step and the diffusion process. It was found that the bronze-IV (Cu–26.8Sn) specimen exhibited the best corrosion resistance, as evidenced by a low corrosion current density and a high impedance. This improvement resulted from an increase in the content of the Cu–Sn solid solution in the alloy, which was conducive to forming a relatively more protective passive film on the surface of the bronze alloy. This finding would be valuable in the anticorrosion protection of archeological artefacts after their excavation.  相似文献   
65.
Developing high-efficiency and low-cost catalysts for hydrogen evolution from hydrolysis of ammonia borane (AB) is significant and critical for the exploitation and utilization of hydrogen energy. Herein, the in-situ fabrication of well-dispersed and small bimetallic RuNi alloy nanoparticles (NPs) with tuned compositions and concomitant hydrolysis of AB are successfully achieved by using graphitic carbon nitride (g-C3N4) as a NP support without additional stabilizing ligands. The optimized Ru1Ni7.5/g-C3N4 catalyst exhibits an excellent catalytic activity with a high turnover frequency of 901 min?1 and an activation energy of 28.46 kJ mol?1 without any base additives, overtaking the activities of many previously reported catalysts for AB hydrolysis. The kinetic studies indicate that the AB hydrolysis over Ru1Ni7.5/g-C3N4 is first-order and zero-order reactions with respect to the catalyst and AB concentrations, respectively. Ru1Ni7.5/g-C3N4 has a good recyclability with 46% of the initial catalytic activity retained even after five runs. The high performance of Ru1Ni7.5/g-C3N4 should be assigned to the small-sized alloy NPs with abundant accessible active sites and the synergistic effect between the composition-tuned Ru–Ni bimetals. This work highlights a potentially powerful and simple strategy for preparing highly active bimetallic alloy catalysts for AB hydrolysis to generate hydrogen.  相似文献   
66.
博斯腾湖泵站分东、西泵站二期建设,本文介绍了博斯腾湖东泵站工程电气一次设计中的接入系统设计、电气主接线、设备选择。  相似文献   
67.
结合经过校正后的适合于本地无线环境的OKUMURA-HATA传播模型,建立起一种新的本地化基于1x EV—DO系统数据业务吞吐量分析的覆盖预测仿真模型,可应用于1xEV—DO系统的网络规划及系统性能分析。  相似文献   
68.
在PTA(精对苯二甲酸)的生产过程中,工艺废气经尾气膨胀透平机降压后进入RTO蓄热式焚烧炉将有毒有害的有机物焚烧分解后排入大气,为了达到粉尘的排放标准(小于120mg/m~3),在焚烧炉之后加上这台高温烟气除尘器,废气经除尘后达到了排放标准,而且最大程度地减少了热量损失,实践证明此项改造是成功的。文章探讨如何进行高温烟气除尘器的设计,并介绍了高温多管陶瓷旋风烟气除尘器的结构。  相似文献   
69.
主要介绍了NEAX61Σ程控交换机远端控制附加业务的功能,以及实现该业务的方法、局数据的设定等。  相似文献   
70.
RFT地层测试器与3700测井系统的配接   总被引:1,自引:0,他引:1  
文章介绍了如何转换CSU系列地层测试器RFT的上传信号,使其能够适应3700测井系统的采集、处理和记录。从而使CSU系列的地层测试器能够配接3700测井系统。  相似文献   
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