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Lei Feng Pengcheng Huo Yuzhang Liang Ting Xu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(27):1903787
Recent advances in nanofabrication technologies have spurred many breakthroughs in the field of photonic metamaterials that provide efficient ways of manipulating light–matter interaction at subwavelength scales. As one of the most important applications, photonic metamaterials can be used to implement novel optical absorbers. First the morphology engineering of various photonic metamaterial absorbers is discussed, which is highly associated with impendence matching conditions and resonance modes of the absorbers, thus directly determines their absorption efficiency, operational bandwidth, incident angle, and polarization dependence. Then, the recent achievements of various interdisciplinary applications based on photonic metamaterial absorbers, including structural color generation, ultrasensitive optical sensing, solar steam generation, and highly responsive photodetection, are reviewed. This report is expected to provide an overview and vision for the future development of photonic metamaterial absorbers and their applications in novel nanophotonic systems. 相似文献
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Bao Zhu Jiefu Chen Wanxie Zhong Qing Huo Liu 《International journal for numerical methods in engineering》2012,92(5):495-506
Two‐dimensional photonic crystal structures are analyzed by a recently developed hybrid technique combining the finite‐element time‐domain (FETD) method and the finite‐difference time‐domain (FDTD) method. This hybrid FETD/FDTD method uses the discontinuous Galerkin method as framework for domain decomposition. To the best of our knowledge, this is the first hybrid FETD/FDTD method that allows non‐conformal meshes between different FETD and FDTD subdomains. It is also highly parallelizable. These properties are very suitable for the computation of periodic structures with curved surfaces. Numerical examples for the computation of the scattering parameters of two‐dimensional photonic bandgap structures are presented as applications of the hybrid FETD/FDTD method. Numerical results demonstrate the efficiency and accuracy of the proposed hybrid method. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Impact of various maceration techniques on the phenolic and volatile composition of Chenin Blanc wines
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Jun Wang Sufang Huo Yuxiu Zhang Yaping Liu Weixin Fan 《International Journal of Food Science & Technology》2016,51(11):2360-2366
Chenin Blanc, cultivated in cool climate regions, was chosen to evaluate the impact of different maceration techniques on polyphenolic profiles and volatile compounds. Control with no skin contact (CK), cold maceration (CM), cryogenic maceration (CR), separate fermentation before blending (SFB) and extended skin contact during fermentation (ESF) were the five maceration techniques being studied. SFB and ESF techniques resulted in significantly increased polyphenolic compounds compared to the control (P < 0.05), while CM and CR maceration techniques resulted in almost no effect. Meanwhile, for aromatic components, the maximum change was observed in ESF wine, which had significantly highest levels of terpenes, alcohols, esters and acids. However, compared with control wine, CR wine had higher levels of terpenes and esters and SFB wine had higher levels of terpenes and alcohols. This study provides information about prefermentation techniques and additional options for oenologists to produce Chenin Blanc wines with different characteristics. 相似文献
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Z. P. Huo M. Zou S. Q. Qin X. Q. Pang W. Y. Wang Q. W. Li 《Petroleum Science and Technology》2016,34(5):471-477
Source rocks generate and expel hydrocarbon with thermal evolution, which lead to a decrease of total organic carbon (TOC) content. A new quantitative model for original total organic carbon (TOCo) content evolution and recovery was proposed, and then was used to the carbonate source rocks with different TOCs (CSRDTOC) in the Tazhong area, Tarim Basin, China. Studies showed that the higher the TOC of source rocks, the bigger the range of TOC reduction and recovery coefficient. When vitrinite reflectance (VR) is equal to 2.5%, recovery coefficients of TOCo = 0.2%, 0.4%, and 1.0% are 1.43, 1.66, and 2.01, respectively. It must restore TOCo when we evaluate source rocks at the stage of high overmaturity and predict oil and gas resources. 相似文献
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The thermal properties of the shape-stabilized phase change material walls with different structure were studied. The phase change material is composed of paraffin mixture and high-density polyethylene. The walls including concrete and shape-stabilized phase change material were prepared respectively by different methods. Preparation methods include direct mixing method and lamination interpolation method. Heat transfer process in the shape-stabilized PCM walls was studied by comparing with traditional wall. The results showed that the surface temperature and the heat flow through the phase change material walls prepared by different methods are lower than that of traditional wall and the change is small. Energy-saving effect of the shape-stabilized PCM walls prepared by lamination interpolation method is better than that of the shape stabilized PCM walls by direct mixing. Results in this paper can provide the basis for the application of the shape stabilized PCM walls in the buildings. 相似文献
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Mechanical and thermal properties of biphenyldiol formaldehyde resin/gallic acid epoxy composites enhanced by graphene oxide
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In this study, the gallic acid‐based epoxy resin (GA‐ER) and alkali‐catalysed biphenyl‐4,4′‐diol formaldehyde resin (BPFR) are synthesized. Glass fibre‐reinforced GA‐ER/BPFR composites are prepared. Graphene oxide (GO) is used to improve the mechanical and thermal properties of GA‐ER/BPFR composites. Dynamic mechanical properties and thermal, mechanical, and electrical properties of the composites with different GO content are characterized. The results demonstrate that GO can enhance the mechanical and thermal properties of the composites. The glass transition temperature, Tg, of the BPFR/GA‐ER/GO composites is 20.7°C higher than the pure resin system, and the 5% weight loss temperature, Td5, is enhanced approximately 56.6°C. When the BPFR: GA‐ER mass ratio is at 4 : 6 and GO content is 1.0–1.2 wt %, the tensile and impact strengths of composites are 60.97 MPa and 32.08 kJ/m2 higher than the pure resin composites, respectively. BPFR/GA‐ER composites have better mechanical properties, and can replace common BPA epoxy resins in the fabrication of composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42637. 相似文献
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