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Xufen Xie Yingying Shang Jieyu Zhu Ningfang Liao Wenmin Wu Jing Liang Chaoqun Fu 《Color research and application》2021,46(1):65-74
Reconstruction of spectral information based on multi‐channel image system is a significant problem in color reproduction, detection, and recognition. A spectral radiance reconstruction from trichromatic digital camera responses is researched in this article. The mapping relationship between the trichromatic imaging system response and the incident spectral radiance is analyzed. Then, in order to remove the ill‐posedness of the problem, a regularized constraint solution model of spectral radiance reconstruction matrix is established. And the spectral radiance can be reconstructed by spectral radiance reconstruction matrices and trichromatic imaging system response. Finally, the spectral radiance reconstruction matrix is estimated by the system radiometric calibration experiment. The input radiance is offered by a LCD display. A 3‐factor and 9‐level orthogonal test is designed for the calibration experiment, and a test set of 24 colors is used for precision analysis. The results show that the average relative mean error of our method is 8.69%, it is lower than that of Wiener filtering method by 2.84%. The method can reconstruct spectral radiance information effectively. 相似文献
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Xiaojun Chen Hongyang Liu Dechao Hu Huaqing Liu Wenshi Ma 《Ceramics International》2021,47(17):23749-23761
With the blossom of information industry, electromagnetic wave technology shows increasingly potential in many fields. Nevertheless, the trouble caused by electromagnetic waves has also drawn extensive attention. For instance, electromagnetic pollution can threaten information safety in vital fields and the normal function of delicate electronic devices. Consequently, electromagnetic pollution and interference become an urgent issue that needs to be addressed. Carbon nanotubes (CNTs) have become a potential candidate to deal with these problems due to many advantages, such as high dielectric loss, remarkable thermodynamic stability, and low density. With the appearance of climbing demands, however, the carbon nanotubes combining various composites have shown greater prospects than the single CNTs in microwave absorbing materials. In this short review, recent advances in CNTs-based microwave absorbing materials were comprehensively discussed. Typically, we introduced the electromagnetic wave absorption mechanism of CNTs-based microwave absorbing materials and generalized the development of CNTs-based microwave absorbers, including CNTs-based magnetic metal composites, CNTs-based ferrite composites, and CNTs-based polymer composites. Ultimately, the growing trend and bottleneck of CNTs-based composites for microwave absorption were analyzed to provide some available ideas to more scientific workers. 相似文献
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针对水泥联合粉磨系统电耗高、出磨水泥温度高、石膏脱水导致的水泥性能差等问题,通过采取高效涡流选粉机、V型选粉机出口增加收尘器、调整篦冷机风机等技改措施,从水泥粉磨工艺上降低了出磨水泥温度,改善了水泥性能,达到了提质降耗的目的。 相似文献
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Ruijie Zhang Lei Wan Huagang Xiao Jiangnan Wang Chengjian Xiao Xiaojun Chen Tao Gao 《Ceramics International》2021,47(14):20239-20247
Li4SiO4 crystal is a candidate material for tritium breeder material. Vacancy defects and He atoms will be produced in the crystal after neutron irradiation in fusion reactor. In previous research, we learned vacancy defects mainly include VO0, VO2+, and VLi0, meanwhile, He atoms are easy to migrate and aggregate in the crystal. In order to understand the relationship between vacancy defects and He atoms, we use density functional theory (DFT) to study the interaction mechanism between vacancy and He atom. The results show that the local stable sites of He atoms are related to the surrounding charge distribution. VO2+ and VLi0 can capture interstitial He atoms, and it is difficult to escape the vacancies, thereby increasing the nucleation center of He atoms. VO0 promotes the diffusion of He atoms in the interstitial space, which will cause small helium bubbles to merge more easily. 相似文献
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Li-Xiang Wu Lin-Lin Zhu Wei-Ming Guo Shi-Kuan Sun Wen-Bin Niu Jia-Xiang Xue Jian-Han Zhai Hai-Bin Ma Rui-Lin Lin Hua-Tay Lin Kevin Plucknett Ye-Hong Liao Tong Liu Qi-Sen Ren 《Journal of the European Ceramic Society》2021,41(1):225-232
The joining of liquid-phase sintered SiC (LPS-SiC) ceramics was conducted using spark plasma sintering (SPS), through solid state diffusion bonding, with Ti-metal foil as a joining interlayer. Samples were joined at 1400 °C, under applied pressures of either 10 or 30 MPa, and with different atmospheres (argon, Ar, vs. vacuum). It was demonstrated that the shear strength of the joints increased with an increase in the applied joining pressure. The joining atmosphere also affected on both the microstructure and shear strength of the SiC joints. The composition and microstructure of the interlayer were examined to understand the mechanism. As a result, a SiC-SiC joining with a good mechanical performance could be achieved under an Ar environment, which in turn could provide a cost-effective approach and greatly widen the applications of SiC ceramic components with complex shape. 相似文献
7.
Shiming Xie Chen Song Zexin Yu Shaowu Liu Frédéric Lapostolle Didier Klein Chunming Deng Min Liu Hanlin Liao 《Journal of the European Ceramic Society》2021,41(1):535-543
Suspension plasma spraying (SPS) as a potential technique to prepare thermal barrier coatings (TBCs) has been attracting more and more attention. However, most reports on SPS were carried out in the atmosphere. Given the unique features of in-flight particles and plasma jets under low pressure, the resulting coatings are expected to be different from those under atmospheric pressure. In this article, yttria-stabilized zirconia (YSZ) thermal barrier coatings were prepared using suspension plasma spraying under different environmental pressures. The results show that as the environmental pressure decreased, the column-like structural coating turned into a vertical crack segmented structure, as well as a dramatic decrease in surface roughness. More nanoparticle agglomerates were formed in the coating under lower environmental pressures. The real porosity of the coating increased with a decrease in environmental pressure. 相似文献
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