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151.
EH Bernhardi MR Khan CG Roeloffzen HA van Wolferen K Wörhoff RM de Ridder M Pollnau 《Optics letters》2012,37(2):181-183
We report the fabrication and characterization of a dual-wavelength distributed-feedback channel waveguide laser in ytterbium-doped aluminum oxide. Operation of the device is based on the optical resonances that are induced by two local phase shifts in the distributed-feedback structure. A stable microwave signal at ~15 GHz with a -3?dB width of 9 kHz was subsequently created via the heterodyne photodetection of the two laser wavelengths. The long-term frequency stability of the microwave signal produced by the free-running laser is better than ±2.5 MHz, while the power of the microwave signal is stable within ±0.35 dB. 相似文献
152.
A micro-bimorph cantilever with self-aligned nanotips is monolithically integrated with a photonic crystal based device using optical and deep UV lithography techniques. Upon electrostatic actuation, the dielectric nanotips perturb the optical field, providing electromechano-optical modulation of light. Static tuning of the optical transmission spectra by more than 600 pm is measured with a sub-1 V drive voltage, resulting in a modulation as high as 21 dB. The observed strong electromechano-optical effect may find application in power efficient devices for optical communication networks, such as wavelength routing elements. 相似文献
153.
Dr. Martha V. Escárcega‐Bobadilla Giovanni Salassa Dr. Marta Martínez Belmonte Eduardo C. Escudero‐Adán Prof. Dr. Arjan W. Kleij 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(22):6805-6810
Supramolecular chirality effects have been achieved both for ditopic and monotopic substrates by using a programmable bis‐salphen scaffold that incorporates either two or three Zn nuclei. The dinuclear host shows preferential chirogenesis in the presence of ditopic systems, whereas effective chirality transfer to the trinuclear complex is realized through monotopic binding. The mode of binding in the trinuclear host has been investigated through X‐ray crystallography, CD measurements, UV/Vis spectroscopy, and DFT analysis. The bis‐salphen scaffold holds promise for the development of substrate‐specific host systems useful for determination of the absolute configuration of various types of organic molecules. 相似文献
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155.
Chemical-Looping Combustion (CLC) has emerged in recent years as a very promising combustion technology for power plants and industrial applications with inherent CO2 capture, which circumvent the energy penalty imposed on other competing technologies. The process is based on the use of a metal oxide to transport the oxygen needed for combustion in order to prevent direct contact between the fuel and air. CLC is performed in two interconnected reactors, and the CO2 separation inherent to the process practically eliminates the energy penalty associated with gas separation. The CLC process was initially developed for gaseous fuels, and its application was subsequently extended to solid fuels. The process has been demonstrated in units of different size, from bench scale to MW-scale pilot plants, burning natural gas, syngas, coal and biomass, and using ores and synthetic materials as oxygen-carriers.An overview of the status of the process, starting with the fundamentals and considering the main experimental results and characteristics of process performance, is made both for gaseous and solid fuels. Process modelling of the system for solid and gaseous fuels is also analysed. The main research needs and challenges both for gaseous and solid fuel are highlighted. 相似文献
156.
Foundations of Chemistry - 相似文献
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159.
Ad. Sommer 《Fresenius' Journal of Analytical Chemistry》1886,25(1):99-100
Ohne Zusammenfassung 相似文献
160.