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991.
Emission spectroscopy of flame fronts in aluminum suspensions 总被引:1,自引:0,他引:1
Samuel Goroshin Jorin Mamen Andrew Higgins Tim Bazyn Nick Glumac Herman Krier 《Proceedings of the Combustion Institute》2007,31(2):2011-2019
Spatially resolved emission spectra from Bunsen-type flames stabilized in aluminum suspensions in air and oxygen–argon/helium mixtures were obtained using a mechanical-optical scanning system. A low resolution (1.5 nm) spectrometer was used to acquire the broad spectra over the 350–1000 nm range, and a high-resolution (0.04 nm) instrument was used for observation of AlO molecular bands and non-ionized atomic aluminum. The temperature of condensed phase emitters in the flame was derived using polychromatic fitting of the continuum spectra to Planck’s law. AlO temperature was found by fitting of the theoretically calculated shape of the band to experimental data. Peak temperatures of the condensed emitters were found to be approximately 3250 K in aluminum-air flames and approximately 3350 K for oxygen–argon/helium flames. Temperatures derived from AlO spectra coincide with the temperature of the condensed emitters with measurement accuracy and are only 100–200 °C lower than the computed equilibrium flame temperatures. The radial distribution of the temperature profile of the continuous emitters was found via Abel deconvolution and recovered the double-front structure of the Bunsen flame cone, with the outer flame being attributed to a diffusion flame of the fuel-rich products with ambient air. The observation of atomic aluminum lines seen in emission from the outer flame edge and partial self-absorption from the inner flame confirms the structure associated with the double-front structure. The implications of these results for the regime of particle combustion in a dust flame are discussed. 相似文献
992.
针对实验中9.5μm峰值响应波长的n型长波量子阱红外探测器设计运用二维金属小球(铜)阵列作光耦合结构.金属小球阵列均匀填充在绝缘的胶黏剂中,基于惠更斯原理研究二维金属小球阵列体系的光耦合和光吸收,结果表明对9.5μm响应波长的长波量子阱红外探测器,采用周期为3μm,半径为0.9μm左右的金属小球阵列可以获得最佳的光耦合.优化设计后的量子效率(66%)远高于45°磨角耦合的量子效率(38%),为实验运用金属小球阵列进行长波量子阱红外探测器的光耦合提供了基本的理论依据和详细的优化设计方案. 相似文献
993.
传输矩阵法分析微环谐振器阵列传输特性 总被引:2,自引:1,他引:2
微环谐振器可用作未来高密度、超大规模集成光路的基本构件,其重要发展方向之一是多环化、阵列化,微环谐振器阵列近来成为研究的热点。基于定向耦合器、环形谐振腔、直波导腔的基本单元传输矩阵,建立了用于分析微环谐振器阵列传输特性的传输矩阵模型。讨论了列间距对传输特性的影响,并数值模拟了不同尺度的奇数行和偶数行情况下谐振器阵列的传输特性。结合此传输矩阵模型,讨论了通过改变微环谐振器阵列的尺度以及耦合系数以实现滤波特性改善的方案。最后数值研究了最小尺度微环谐振器阵列传输特性与腔间耦合系数的关系。 相似文献
994.
Nakao Masashi Oku Satoshi Tanaka Hidenao Shibata Yasuo Yokoo Atsushi Tamamura Toshiaki Masuda Hideki 《Optical and Quantum Electronics》2002,34(1-3):183-193
A two dimensional (2D) GaAs hole array with a high aspect ratio was successfully fabricated by dry etching techniques using a highly ordered alumina membrane as a mask. The reflection spectra of the GaAs hole array shows characteristics of the photonic bandgap (PBG) calculated by using the 2D triangular lattice structure. Various defect lines were formed etching in the GaAs hole array using focused ion beam. The defect-type PBG waveguide was experimentally demonstrated. 相似文献
995.
996.
A fully automated synthesizer was constructed and designed to perform high speed miniaturized syntheses of compound libraries using the SPOT technique. Utilizing magnetically controlled drop-on-demand ink jet nozzles, an r/phi array format of 2500 spots can be simultaneously dispensed from up to 24 separate reagent valves onto a rotating disc as the solid phase in less than three minutes. In addition, a complete wash station is on board allowing for fully programmable combinatorial syntheses without manual attention. A new carbon black/polypropylene composite solid phase disc was developed and tested for its functionalisation/loading, spot detection, durability and MALDI-TOF target capabilities. The carbon black/polypropylene composite was then successfully employed jointly as the solid phase in the syntheses of short peptide and PNA oligomers and as the target probe holder for MALDI-TOF measurement without transfer of the material. Several protocols for PNA syntheses were also investigated and an optimised PNA methodology for the carbon black/polypropylene composite is reported. 相似文献
997.
998.
999.
Let n and k be positive integers. Let Cq be a cyclic group of order q. A cyclic difference packing (covering) array, or a CDPA(k, n; q) (CDCA(k, n; q)), is a k × n array (aij) with entries aij (0 ≤ i ≤ k−1, 0 ≤ j ≤ n−1) from Cq such that, for any two rows t and h (0 ≤ t < h ≤ k−1), every element of Cq occurs in the difference list
at most (at least) once. When q is even, then n ≤ q−1 if a CDPA(k, n; q) with k ≥ 3 exists, and n ≥ q+1 if a CDCA(k, n; q) with k ≥ 3 exists. It is proved that a CDCA(4, q+1; q) exists for any even positive integers, and so does a CDPA(4, q−1; q) or a CDPA(4, q−2; q). The result is established, for the most part, by means of a result on cyclic difference matrices with one hole, which is of interest in its own right. 相似文献
1000.
John?P.?McsorleyEmail author N.?C.?K.?Phillips W.?D.?Wallis J.?L.?Yucas 《Designs, Codes and Cryptography》2005,35(1):21-45
Triple arrays are a class of designs introduced by Agrawal in 1966 for two-way elimination of heterogeneity in experiments. In this paper we investigate their existence and their connection to other classes of designs, including balanced incomplete block designs and balanced grids.AMS Classification:05B05, 05B30 相似文献