共查询到18条相似文献,搜索用时 79 毫秒
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阐述了太赫兹隐身和屏蔽性能分析的计算模型, 并对几种典型的太赫兹隐身和屏蔽材料进行了综述和介绍, 指出了当前研究存在的问题以及今后的发展方向. 相似文献
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以水性聚氨酯为粘合剂,掺杂Al和La的ZnO为填料,配以其它助剂制成了红外隐身涂料,应用在帐篷织物表面,探究涂层厚度以及填料含量对红外发射率的影响,并研究了导热系数和红外隐身性能之间的关系。 研究发现,涂层厚度和填料含量对涂层织物的红外发射率有着显著的影响。 当填料质量分数为70%时,得到的帐篷涂层织物的红外发射率可降至0.622,调节填料含量和涂层厚度,可以的得到红外发射率在0.622~0.932之间的帐篷涂层织物。 此外,发现导热系数对红外隐身性能也有一定的影响,红外隐身性能随着导热系数的增加而提高。 通过调节填料含量和涂层厚度制作不同红外发射率的涂层帐篷织物,放在不同背景下拍摄红外热成像图,发现涂层在不同的环境中均具有良好的伪装能力。 相似文献
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介绍利用红外或红色激光泵浦掺稀土固体材料直接输出蓝绿激光的途径和研究进展:较为详细地介绍了红外激光泵浦掺稀土非线性激光晶体通过自变频过程,以及红外激光泵浦掺稀土固体块状,光纤和微珠材料通过频率上转换过程实现蓝绿激光输出的研究结果,并与其它输出蓝绿波段激光的器件和方法进行比较,着重对比分析了YAl3(BO3)4,GdAl3(BO3)4,Ca4YO(BO3)3和Ca4GdO(BO3)等典型的非线性激光基质晶体以及氟化物光纤等典型的上转换激光介质材料,对该领域目前面临的主要问题和发展方向进行了探讨。 相似文献
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能源与环境现状迫切要求开发出具有节能特性的新一代智能建筑窗户,以有效降低建筑能源消耗。热致变色材料能够根据外界温度变化改变自身光学性质,智能地调节进入室内的太阳辐射能量,且不消耗其他能源,在建筑节能方面具有极大的应用潜力。常见的热致变色材料包括水凝胶、离子液体、钙钛矿、超材料、液晶和VO2等。其中VO2在相变前后透过率在近红外区域明显降低而在可见光范围内保持不变,是热致变色智能窗材料的理想选择之一。本综述概述了热致变色涂层相关材料的工作原理、构筑方法及最新研究进展。首先介绍了常见热致变色材料的结构特性和相变机制。之后以VO2为例,阐明了智能窗涂层表面工程设计和优化方法,讨论了不同构筑手段对光学性能的影响。最后,梳理了目前热致变色智能涂层所存在的不足及面临的困难,并对未来的研究方向进行了展望。 相似文献
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采用热还原法在不同退火温度(从100到1200℃)下制备了一系列还原氧化石墨烯(rGO)薄膜,并通过X射线粉末衍射(XRD)、傅里叶变换红外光谱(FTIR)、拉曼光谱、四探针电阻仪和扫描电镜(SEM)对其进行了表征和分析.随后利用旋涂封装法制备了聚二甲基硅氧烷(PDMS)封装的石墨烯基柔性红外探测器(P-rGO-P),并成功用于红外激光、人体红外辐射、弯曲变化和压力探测.实验结果表明,采用不同温度还原的rGO薄膜封装得到的P-rGO-P柔性红外探测器在近红外(1064 nm)激光照射下均有响应,其中最高的光响应可达2.78 mA/W.此外,P-rGO-P柔性探测器对人体红外辐射和弯曲变化也具有快速、灵敏的响应,并且经过反复弯折仍能保持完整性与响应能力. 相似文献
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通过热解金属有机骨架ZIF-67的方法成功制备了具有优异微波吸收性能的Co/C碳基复合材料。 在600 ℃热解温度下获得的吸收剂质量分数为35% 的样品,最小反射损耗可达到-54.30 dB,其厚度仅为1.75 mm。 通过分析样品的损耗能力和阻抗匹配等微波吸收特性,发现复合材料中的骨架结构等对其阻抗匹配性能有非常大的影响。 并通过原位复合的方法制备了分散均匀的Co/C-PU相变复合材料,初步研究了其微波-热转换性能。 实验表明,微波吸收剂的添加量对其微波-热转换性能影响显著,发热效率随添加量成倍升高。 本文研究的Co/C-PU相变复合材料在电磁屏蔽、雷达红外兼容隐身等方面具有很大的应用潜力。 此外,固固相变材料结合微波热效应的快速高效等特点,用于储能或者其他热应用也有独特的优势。 相似文献
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微波的频率高、波长短,具有似光波和似声波的特征,能形成方向性极强的波束,且其频带宽,携带信息量大,可无阻碍地穿透高空电离层等特点,在雷达、通信、电子对抗等方面得到了广泛的应用[1].微波吸收材料是在防止被雷达探测及跟踪而研究发展起来的隐身材料. 相似文献
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文章介绍了有关隐身技术的基础知识,以及导电高分子材料在隐身技术中的应用.根据导电机理的不同,导电高分子隐身材料可分为结构型和复合型,两者在实际应用过程中各有优缺点,文章分别对其作了简单的介绍和讨论.并且针对近几年来复合材料领域的研究热点--碳纳米管纳米复合材料在隐身技术中的应用作了详细介绍. 相似文献
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Dr. Susanne Schöttler Prof. Dr. Katharina Landfester Prof. Dr. Volker Mailänder 《Angewandte Chemie (International ed. in English)》2016,55(31):8806-8815
The past decade has seen a significant increase in interest in the use of polymeric nanocarriers in medical applications. In particular, when used as drug vectors in targeted delivery, nanocarriers could overcome many obstacles for drug therapy. Nevertheless, their application is still impeded by the complex composition of the blood proteins covering the particle surface, termed the protein corona. The protein corona complicates any prediction of cell interactions, biodistribution, and toxicity. In particular, the unspecific uptake of nanocarriers is a major obstacle in clinical studies. This Minireview provides an overview of what we currently know about the characteristics of the protein corona of nanocarriers, with a focus on surface functionalization that reduces unspecific uptake (the stealth effect). The ongoing improvement of nanocarriers to allow them to meet all the requirements necessary for successful application, including targeted delivery and stealth, are further discussed. 相似文献
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Marius Bauer Christian Lautenschlaeger Kristian Kempe Lutz Tauhardt Ulrich S. Schubert Dagmar Fischer 《Macromolecular bioscience》2012,12(7):986-998
Limitations of PEG in drug delivery have been reported from clinical trials. PEtOx (0.4–40 kDa) as alternative is synthesized by a living, microwave‐assisted polymerization, and is directly compared to PEG of similar molar mass regarding cytotoxicity and hemocompatibility. In short‐term treatments, both types of polymers are well tolerated even at high concentrations. Moderate concentration and molar mass dependent cytotoxic effects occurred only after long‐term incubation at concentrations higher than therapeutic doses. PEtOx possesses not only an easy route of synthesis and beneficial physicochemical characteristics such as low viscosity and high stability, which are advantageous over PEG, but additionally in vitro toxicology comparable to PEG.
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Johanna Simon Thomas Wolf Katja Klein Prof. Dr. Katharina Landfester Priv.‐Doz. Dr. Frederik R. Wurm Prof. Dr. Volker Mailänder 《Angewandte Chemie (International ed. in English)》2018,57(19):5548-5553
Increasing the plasma half‐life is an important goal in the development of drug carriers, and can be effectively achieved through the attachment of polymers, in particular poly(ethylene glycol) (PEG). While the increased plasma half‐life has been suggested to be a result of decreased overall protein adsorption on the hydrophilic surface in combination with the adsorption of specific proteins, the molecular reasons for the success of PEG and other hydrophilic polymers are still widely unknown. We prepared polyphosphoester‐coated nanocarriers with defined hydrophilicity to control the stealth properties of the polymer shell. We found that the log P value of the copolymer controls the composition of the protein corona and the cell interaction. Upon a significant change in hydrophilicity, the overall amount of blood proteins adsorbed on the nanocarrier remained unchanged, while the protein composition varied. This result underlines the importance of the protein type for the protein corona and cellular uptake. 相似文献
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[formula: see text] Polyethylene glycol (PEG) has proven to be a versatile soluble-polymer support for organic synthesis, though the use of PEG has been limited by its relatively low loading (0.5 mmol/g or less). We have developed a new high-loading (1 mmol/g) soluble-star polymer based on a cyclotriphosphazene core with PEG arms that exhibit superior precipitation properties compared with those of linear PEG. Additionally, the heterocyclic core does not add interfering signals to the 1H or 13C NMR. 相似文献
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Molecularly Imprinted Nanogels Acquire Stealth In Situ by Cloaking Themselves with Native Dysopsonic Proteins 下载免费PDF全文
Prof. Dr. Toshifumi Takeuchi Dr. Yukiya Kitayama Reo Sasao Takuya Yamada Dr. Kazuko Toh Dr. Yu Matsumoto Prof. Dr. Kazunori Kataoka 《Angewandte Chemie (International ed. in English)》2017,56(25):7088-7092
Protein corona formation was regulated on the surface in vivo by molecular imprinting to enable polymeric nanogels to acquire stealth upon intravenous administration. Albumin, the most abundant protein in blood, was selected as a distinct protein component of protein corona for preparing molecularly imprinted nanogels (MIP-NGs) to form an albumin-rich protein corona. Intravital fluorescence resonance energy transfer imaging of rhodamine-labeled albumin and fluorescein-conjugated MIP-NGs showed that albumin was captured by MIP-NGs immediately after injection, forming an albumin-rich protein corona. MIP-NGs circulated in the blood longer than those of non-albumin-imprinted nanogels, with almost no retention in liver tissue. MIP-NGs also passively accumulated in tumor tissue. These data suggest that this strategy, based on regulation of the protein corona in vivo, may significantly influence the development of drug nanocarriers for cancer therapy. 相似文献
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Flexible and wearable strain sensors for human-computer interaction, health monitoring, and soft robotics have drawn widespread attention to promising applications in the next generation of artificial intelligence devices. However, conventional semiconductor sensors are difficult to meet the requirements of flexibility and stretchability. Here, we reported a kind of novel and simple sensor based on layer-by-layer(LBL) method. Carbon nanotubes (CNTs) layer provides high ductility and stability in the process of tension sensing, while silver layer provides low initial resistance and fast reflecting in the process of tension sensing. LBL method ensures the uniformity of the conductive layer. The sensor has superior sheet resistance of 9.44Ω/sq., high elongation at break of 104%. For sensing capability, the sensor has wide reflecting range of 60%, high gauge factor (GF) of 1000 up to 60%strain, fast reflecting time of 165 ms. Excellent reliability and stability have also been verified. It is also worth mentioning that the entire process does not require any expensive equipments, complicated processes or harsh experimental conditions. The above features provide an idea for large-scale application of flexible stretchable sensors. 相似文献