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971.
The thermolysis of dicarbonylcyclopentadienyliron dimer in a sealed tube at 300°C has been reported to produce ferrocene, carbon monoxide, carbon dioxide, cyclopentadiene and elemental iron. We observe in addition to these products the production of biferrocene and elemental carbon. Thermolysis of carbonylcyclopentadienyliron tetramer (produced from the dimer by thermolysis in refluxing xylene) produces ferrocene, iron and carbon monoxidre; no biferrocene, carbon dioxide or elemental carbon are produced. A scheme is proposed to account for these products. 相似文献
972.
973.
The optimal design of the high power plate and grid modulated selective amplifier is examined in this paper. For the analysis purposes, the linear model of constant plate current characteristics for HF power triode is applied. The carrier wave state of the unmodulated amplifier is chosen so to enable the realization of the high levels of modulation. The results are obtained immediateZy, and the estimated error is acceptable. The estimated characteristic values of this high power and high efficiency HF amplifier are shown in the corresponding diagrams. 相似文献
974.
975.
Three new magnetic oxides have been synthesised, viz., Li2Fe3VO8, YFe3TiO8 and CaFe3VO8. XRD studies show that the first compound has a cubic symmetry of spinel type while the latter two show orthorhombic symmetry. All the three compounds are magnetic at room temperature, however, the first compound shows a large magnetic moment as compared to the other two. Their Mössbauer spectra at room temperature show distinct hyperfine split spectral lines. The present preliminary investigation indicates that the long range order is ferrimagnetic in Li2Fe3VO8 and CaFe3VO8 while in YFe3TiO8 it is more likely to be canted antiferromagnetic. 相似文献
976.
A. Kavokin 《Applied Physics A: Materials Science & Processing》2007,89(2):241-246
An overview is given of the current research trends in the physics of exciton-polaritons in microcavities. Potential applications
of the Bose–Einstein condensation and superfluidity of exciton-polaritons are discussed. The perspectives for the realization
of polariton lasers, polariton spin transistors and polarization modulators are presented.
PACS 78.67.-n; 71.36.+c; 42.55.Sa; 42.25.Kb 相似文献
977.
We have performed structural and optical characterizations of the propolis (an organic entity of biological nature) films grown on various non-organic substrates. The films were grown from a propolis melt or a propolis alcohol solution. The crystal structure has been observed in the films precipitated from the solution onto substrates such as an amorphous glass and sapphire or semiconductor indium monoselenide. For any growth method, the propolis film is a semiconductor with the bandgap of 3.07 eV at 300 K that is confirmed by a maximum in photoluminescence spectra at 2.86 eV. We argue that propolis films might be used in various optoelectronic device applications. 相似文献
978.
979.
980.
Saponara S. Fanucci L. Marsi S. Ramponi G. Kammler D. Witte E.M. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2007,54(7):596-600
This brief presents an application-specific instruction-set processor (ASIP) for real-time Retinex image and video filtering. Design optimizations are addressed at algorithmic and architectural levels, the latter including a dedicated memory structure, an adapted pipeline, bypasses, a custom address generator and special looping structures. Synthesized in CMOS technology, the ASIP stands for its better energy-flexibility tradeoff versus reference ASIC and digital signal processing Retinex implementations. 相似文献