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71.
Filter synthesis for periodically coupled microring resonators 总被引:3,自引:0,他引:3
The theory of filter synthesis using periodically coupled microring resonators is developed as a means to overcome the fabrication sensitivities inherent in conventional higher-order filters, while still achieving desirable spectral characteristics. Each resonator in the array can compensate for deficiencies in any of the others. These filters exhibit a boxlike shape and very high extinction ratios. 相似文献
72.
The Mössbauer spectra of 57Fe in CoSi2 have been measured in 3.5 and 4.0 T external magnetic fields. The measured spectra showed only magnetic splitting thereby proving the cubic symmetry around 57Fe atoms in CoSi2 (fluorite‐type lattice). Two iron positions were found: in one the iron atoms substitute Co atoms, in the other one the iron populates the empty cubic site in the lattice. It is considered that the results may well contribute to clarifying the atomic positions and local symmetries in metastable Co‐ and Fe‐silicides forming after implantation of Co and Fe in Si at elevated temperatures. 相似文献
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Matt Grupen Paul Sotirelis Steve Wong John Albrecht Robert Bedford Sarah Maley Tom Nelson Bill Siskaninetz 《Optical and Quantum Electronics》2008,40(5-6):349-354
A unique discretization scheme that couples Maxwell’s full wave vector field equations self-consistently with nonlinear charge and energy transport is presented. The scheme is used to simulate laser modulation achieved in a simple electrically pumped quantum well laser diode by dynamically heating the degenerate quantum charge gases with high frequency radiation. 相似文献
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Jim Luong Ronda Gras Roger Firor Lyndon Sieben Bill Winniford Hernan Cortes 《Journal of chromatography. A》2009,1216(14):2740-2748
A dual-purpose gas chromatographic injection device, capable of injecting pressurized liquid sample of up to 5000 psig and gas sample with a volume as high as 5000 μL, has been successfully developed and implemented. The injection device is synergized by the effectiveness of a classical flash vaporization of a syringe injection and the reliability of a proven rotary valve. Depending on the matrix involved, this injection device employs either a commercially available four-port internal valve for liquid sampling or a six-port external valve for gas sampling, a modified removable needle used in standard liquid syringe, and an auxiliary flow stream that can be either mechanical or electronic flow controlled for solute transfer. For pressurized liquid, the device was found suitable of up to nC16 hydrocarbon with no observable carry-over despite the injection device was operating at ambient temperature. A relative standard deviation of less than 2% (n = 20) was obtained for hydrocarbon compounds ranging from nC8 to nC16. For gas injection, the device performed well even under difficult chromatographic conditions such as with a low column inlet pressure of less than 1 psig. A relative standard deviation of less than 0.5% (n = 10) was obtained for reactive sulfur compounds such as alkyl mercaptans. The device can be operated manually or automated with pneumatic or electrical actuator, is platform neutral, and can be moved amongst instruments without hardware modification as well as implemented for on-line or in situ applications. In this paper, the utility of the device was also demonstrated with selected GC applications of industrial significance. 相似文献
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