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61.
多光束全息互连元件往往需要大量的耦合波方程才能描述。本文通过分析记录时生成的互调制光栅的性质及其对衍射的影响,对问题进行适当的简化。通过解不同条件下的耦合波方程、分别给出了多光束全息图在各种不同情况下的衍射效率的近似解析表达式,展示了衍射效率与各实验参量之间的关系。为进一步研究多光束全息互连元件的性质、比较各种条件下的效率以及各参量对总体效率的影响,提供了方便。 相似文献
62.
The period interaction on diffraction of the blazed transmission gratings is analyzed with a modified extended scalar theory. For one certain period, the lights reflected from the neighboring structures can be refracted by the grating facets and form two extra fields on the bottom facet of blazed transmission gratings. The effects of this period interaction versus several diffraction orders for a fixed fabrication error of blazed transmission gratings with intermediate structures are discussed for both TE and TM polarizations. The results have been compared with those obtained with finite-difference time-domain method. 相似文献
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住宅设计必须满足和适应住户的生活实态和意愿变化,不同的家庭类型有不同的生活实态的空间需求。知识型家庭是一个特殊的群体。本文通过对不同城市、不同职别的220户知识分子家庭的调查研究,提出知识型家庭的结构模型,记录了他们的居住实态,预测了其潜在的需求意愿,在此基础提出了适合知识型家庭使用的新住宅设计的几个重要结论 相似文献
65.
Hydrophobins are small fungal proteins, which have remarkable surface-chemical properties. They self-assemble at hydrophobic/hydrophilic interfaces and work as adhesive agents and coatings. Sixteen layer Langmuir-Blodgett films of hydrophobins HFBI and HFBII from the fungus Trichoderma reesei were prepared and studied using grazing-incidence X-ray diffraction and reflectivity techniques. Both kind of films contain hexagonally ordered crystallites on the substrate with unit cell parameters of a = b = 54 Å (HFBI) and a = b = 55 Å (HFBII). The structure is similar to the structure of monolayer Langmuir-Blodgett films. 相似文献
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Khaled Boughzala Nadia Gmati Khaled Bouzouita Ali Ben Cherifa Pierre Gravereau 《Comptes Rendus Chimie》2010,13(11):1377-1383
Several studies demonstrated the ability of britholites to retain radionuclides such as the caesium and actinides. Therefore, three compounds with formulas Sr8LaCs(PO4)6F2, Sr7La2Cs(PO4)5(SiO4)F2 and Sr2La7Cs(SiO4)6F2, were prepared by solid state reaction. However, it seems that only the mono-silicated composition was obtained in a pure state. In this present work, the X-ray diffraction and magnetic nuclear resonance have been used to investigate the structure for this composition. The results showed that in fact this phase was not pure, but it was mixed with a secondary phase, SrLaCs(PO4)2. The refinement by the Rietveld method allowed also to precise the distribution of La3+ and Cs+ ions between the two cationic sites of the apatite. 相似文献
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S. Savenkov R. Muttiah A. Klimov 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(11):1796-1802
The problem of measurement of block-diagonal scattering matrix as being part of the so-called incomplete or partial Mueller polarimetry is addressed. It has been shown that non-zero elements of the scattering matrix with block-diagonal structure can be measured using only two elliptical polarizations of input light. Optimal pairs of these polarizations are derived. Utilization of the optimal input polarizations results in halving measurement time and decreasing measurement errors by 30%. 相似文献
70.
Amin Khavasi 《Optics Communications》2011,284(13):3211-3215
The performance of the adaptive spatial resolution technique is improved by making the resolution function of the coordinate transformation as smooth as possible. To this end, the smoothness of the resolution function is probed and a quantitative criterion is proposed to make the jump points; which were conventionally equidistant from each other, regularized. The here-proposed regularization is applied to two different recent formulations and its effects on the overall convergence rate and on the presence of numerical artifacts in analysis of highly conducting gratings are studied. Dielectric and metallic gratings at optical and microwave frequencies are considered and the helpfulness of the proposed technique is discussed. 相似文献