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521.
部分相干Airy光束及其传输的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
崔省伟  陈子阳  胡克磊  蒲继雄* 《物理学报》2013,62(9):94205-094205
利用高斯-谢尔模型的交叉谱密度公式和惠更斯衍射积分, 得到了部分相干Airy光束的表达式. 对不同相干度的部分相干Airy光束的无衍射和横向加速偏移的性质进行了理论分析并予以实验验证, 结果一致表明部分相干Airy光束也具有无衍射和横向加速度的特性, 而且相干度越低, 部分相干Airy光束的无衍射距离越短, 横向加速度越小. 关键词: 傅里叶光学 全息 部分相干 艾里光束  相似文献   
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In the past two decades, perylenequinonoid derivatives (PQD), such as hypocrellin A (HA), hypocrellin B (HB) and hypericin (HYP) have attracted considerable attention owing to their excellent properties of photosensitization and great advantages over the investigation of intramolecular proton transfer (IPT)1-5. Previous researches demonstrated that IPT both in the ground state and excited states exists in PQD and is critical for PQD to reserve their photosensitive activity3,6. Altho…  相似文献   
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The κ-carrageenan comes from a family of linear water-soluble polysaccharides extracted from different species of marine red algae with a primary structure of an alternating disaccharide with repeating unit of 3-linked β-D-galactose 4-sulfate and 4-link…  相似文献   
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Amphiphilic block copolymers have attracted great interest recently, especially for thebiomedical uses1, . The hydrophilic blocks improve the biocompatibility of copolymer, 2while the hydrophobic blocks enhance the mechanics of the material and providever…  相似文献   
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Introduction Separation,recoveryofolefinorremovalof tracequantitiesofolefinfromitsmixturesbyusing π-complexatonisamostpromisingsolution,com- paredwithenergy-intensivedistillationorotheral- ternatives.π-Complexationisasubgroupofchemi- calcomplexationwhereamixtureisbroughtinto contactwithasecondphasecontainingacomplex- ingagent[1].Forexample,theadsorbentscontain- ingAg+orCu+canselectivelyadsorbolefinfroman ethylene/ethaneorpropylene/propanemixture. Becausetheπ-complexationbondsarestronger th…  相似文献   
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Due to the framework chirality optically active clusters can provide the proof that a cluster as a whole, and not one of its fragments, acts as a catalyst, most of the work have been directed to the synthesis of tetrahedron-type chiral clusters1-3. However, there remains another major problem to obtain the pure enantiomers. Although Vahrenkamp had obtained some pioneering results in this area before 19901, only several racemic chiral clusters have been separated into pure enantiomers until now…  相似文献   
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Crown compounds offer a variety of interesting functions based on their specific bindings of organic guest species1,2. In particular, they can act as carriers in ion- extraction, membrane transport, and phase-transfer reactions. In contrast to the large variety of synthetic ionophores for cation transport, there are only a few examples of synthetic anion transport ionophores. Therefore, it appears highly desirable to search for a new class of ionophores with excellent transport abilities fo…  相似文献   
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IntroductionPlants have a more extensive biosynthetic capacitythan animals, which is attributed to the fact that ani-mals rely on their diet for the supply of many biochemi-cal compounds and their precursors. Owing to thisdifference, plants contain numero…  相似文献   
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The fission product 137Cs accounts for a large fraction of the radioactivity in high-levelnuclear waste (HLW). Because of the hazard to environment and the widespreadapplication of 137Cs gamma radiatior1, a need has arisen to develop improved methods forthe removal and recovery of radiocesium from these wastes. Reports have shown thatsome calixcrown compounds may be highly selective for Cs cation2, but, since thesynthesis of them is difficult and the cost is high, it might obviate their use…  相似文献   
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