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The body color in animals results from billions of years of their natural evolution in order to evade natural enemies, catch
quarries or display themselves beauty, investigation on mechanisms of structural light is an important aspect of bionics.
Based on the phenomenon of Papilio maackii ménétriès’ blue scales changing into green ones immediately after dropping some alcohol aqua on the underwing surface and
soon returning back to the original color, the relationship between microstructure, optics characteristic of scales and changing
color effect were studied using the Olympus Stereomicroscope, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy
(TEM) and Ultraviolet (UV)-Visible Spectrophotometer. The color variation mechanisms of blue scales of Papilio maackii ménétriès in Chinese Northeast were revealed in this paper. When visible lights traveled through the concaver structure with
multilayer reflector and the filled medium with different refractive indices, the reflected lights in definite wavelengths
produced interference and color at that wavelength came into being. It has important academic reference value to biomimetics
design of video stealth materials.
Recommended by Prof. SONG YuQuan, Member of Editorial Committee of Science in China, Series E: Technological Sciences
Supported by the National Natural Science Foundation of China (Grant Nos. 50635030, 30570235), the Key Project of Chinese
Ministry of Education (Grant No. 105059), and Fok Ying Tong Education Foundation (Grant No. 101020) 相似文献
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针对我国煤矿生产管理现状,研究了采掘设计、采掘计划和采掘测量管理等问题,建立了相应的管理系统数学模型,开发了煤矿采掘工程平面图动态管理系统。该系统可解决采掘数据、采掘图形以及两者之间的动态管理问题,使采掘设计、采掘计划和采掘测量的管理融为一体,实现煤矿采掘生产动态管理。实际应用证明,该系统使用效果良好。 相似文献
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在我们的日常工作中,每天滚动播出的每一条新闻片子都要在配音间由录音师进行配音及合成,然后经过有关领导审查,通过了才可送到播出线。但是常常会遇到这种情况:新闻片子在配音间配音完毕后,经领导审查,认为有些画面需要进行修改,编辑记者就会到自编间调整画面,然后再送到审看间,重新请领导再次审查。领导审查时,画面内容虽说通过了,但有时又出现了声音上的问题,表现为背景声过大,甚至压过了解说的音量,使人无法听清解说词的内容,造成解说与效果声互相干扰,更为严重的是有些新闻片子在修改后没有时问重审,而是直接送到了播出线播出,结果造成了播出事故,为什么会出现这种情况?原因是什么呢? 相似文献
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Two cadmium inorganic–organic hybrid coordination polymers [CdL(SCN)2]n (1) and [CdLI2]n (2), have been synthesized and characterized by IR spectroscopy, elemental analysis, XRPD, thermogravimetric (TG) analyses and X-ray crystallography, where L is 4-(pyridine-4-yl)methyleneamino-1,2,4-triazole. Asymmetrical Schiff-base ligand L acts as a bidentate bridging ligand to bind two Cd(II) centers through two terminal Ntriazolyl and Npyridyl donors in polymers 1 and 2. Polymer 1 displays a new 3D inorganic–organic hybrid network generated through the coordination interactions between Cd-(1,3-μ-SCN−) 2D inorganic sheets and bidentate bridging ligands. The structure of polymer 2 is a 3D chiral supramolecular framework which contains helical chains on 21 axis. Each Cd(II) center is coordinated by two ligands and two I− donors to attain a distorted tetrahedral environment. The luminescent properties of polymers 1 and 2 were investigated in the solid state at room temperature. 相似文献
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REN LuQuan QIU ZhaoMei HAN ZhiWu GUAN HuiYing & WU LiYan Key Laboratory for Terrain-Machine Bionics Engineering Ministry of Education College of Biological Agricultural Engineering Jilin University Changchun China 《中国科学E辑(英文版)》2007,50(4):430-436
The body color in animals results from billions of years of their natural evolution in order to evade natural enemies, catch quarries or display themselves beauty, in-vestigation on mechanisms of structural light is an important aspect of bionics. Based on the phenomenon of Papilio maackii ménétriès’ blue scales changing into green ones immediately after dropping some alcohol aqua on the underwing sur-face and soon returning back to the original color, the relationship between micro-structure, optics characteristic of scales and changing color effect were studied using the Olympus Stereomicroscope, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Ultraviolet (UV)-Visible Spectropho-tometer. The color variation mechanisms of blue scales of Papilio maackii mé-nétriès in Chinese Northeast were revealed in this paper. When visible lights trav-eled through the concaver structure with multilayer reflector and the filled medium with different refractive indices, the reflected lights in definite wavelengths pro-duced interference and color at that wavelength came into being. It has important academic reference value to biomimetics design of video stealth materials. 相似文献
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本文通过分析炼钢高炉上料小车系统对控制技术的需求,介绍了在自动控制中采用变频器实现调速的方法,并探讨了变频器的抱闸控制逻辑和时序,通过S7-300 PLC控制系统给出控制信号,完成整个系统的自动控制,达到生产工艺的要求。经试验证明:该控制系统具有效率高、能耗低、故障率低等优点,具有较好的实用性能和市场价值。 相似文献
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Effect of Different Solvents on the Measurement of Phenolics and the Antioxidant Activity of Mulberry (Morus atropurpurea Roxb.) with Accelerated Solvent Extraction
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Jiufang Yang XiaoQun Ou Xiaoxu Zhang ZiYing Zhou LiYan Ma 《Journal of food science》2017,82(3):605-612
The effects of 9 different solvents on the measurement of the total phenolics and antioxidant activities of mulberry fruits were studied using accelerated solvent extraction (ASE). Sixteen to 22 types of phenolics (flavonols, flavan‐3‐ols, flavanol, hydroxycinnamic acids, hydroxybenzoic acids, and stilbenes) from different mulberry extracts were characterized and quantified using HPLC‐MS/MS. The principal component analysis (PCA) was used to determine the suitable solvents to distinguish between different classes of phenolics. Additionally, the phenolic extraction abilities of ASE and ultrasound‐assisted extraction (UAE) were compared. The highest extraction efficiency could be achieved by using 50% acidified methanol (50MA) as ASE solvents with 15.14 mg/gallic acid equivalents g dry weight of mulberry fruit. The PCA results revealed that the 50MA followed by 50% acidified acetone (50AA) was the most efficient solvent for the extraction of phenolics, particularly flavonols (627.12 and 510.31 μg/g dry weight, respectively), while water (W) was not beneficial to the extraction of all categories of phenolics. Besides, the results of 3 antioxidant capability assays (DPPH, ABTS free radical‐scavenging assay, and ferric‐reducing antioxidant power assay) showed that water‐based organic solvents increased the antioxidant capabilities of the extracts compared with water or pure organic solvents. ASE was more suitable for the extraction of phenolics than UAE. 相似文献
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