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111.
112.
High-Q microwave photonic filter with a tuned modulator 总被引:1,自引:0,他引:1
We propose the use of tuned electro-optic or electroabsorption external modulators to implement high-quality (high-Q) factor, single-bandpass photonic filters for microwave signals. Using this approach, we experimentally demonstrate a transversal finite impulse response with a Q factor of 237. This is to our knowledge the highest value ever reported for a passive finite impulse-response microwave photonic filter. 相似文献
113.
In this note we show that a diffeomorphism which has a Hopf's bifurcation point, can be perturbed around the bifurcation point in order to get a diffeomorphism which exhibits homoclinic tangencies. In the case this is not possible because of the typical unfolding of a Hopf's bifurcation point.
114.
DC magnetic field generation in resonance absorption is studied, in a non-linear regime, when it becomes of sufficient order of magnitude to affect wave propagation, as well as electron-ion collisions or thermal dispersion do. It is shown that a simple expression obtained in the linear regime is still valid in the non-linear theory. Scaling laws are set up. 相似文献
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Ohne Zusammenfassung 相似文献
116.
Cristoni S Cuccato D Sciannamblo M Bernardi LR Biunno I Gerthoux P Russo G Weber G Mora S 《Rapid communications in mass spectrometry : RCM》2004,18(1):77-82
Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder mainly caused by 21-hydroxylase deficit (21-OHD). Deletions or mutations of the CYP21 gene induce the impairment of glucocorticoid and mineralcorticoid synthesis. 17-Hydroxyprogesterone (17-OHP) is the hormonal marker in patients, but not in the heterozygous subjects. Excess 17-OHP is hydroxylated into 21-deoxycortisol (21-DF), and therefore 21-DF can be used as a specific marker for diagnosis of heterozygous individuals. We report an analytical method for analysis of 21-DF in blood samples using electrospray (ESI) and atmospheric pressure chemical ionization (APCI), showing that ESI is very sensitive for the analysis of this marker molecule. The multiple reaction monitoring (MRM) approach was used to increase the specificity and the sensitivity of the method. 相似文献
117.
Martinez-Montero ME Mora N Quiñones J González-Arnao MT Engelmann F Lorenzo JC 《Cryo letters》2002,23(4):237-244
In this paper, we investigated if the differences consistently noted in survival and plantlet production between cryopreserved and non-cryopreserved, control sugarcane embryogenic calluses were related to modifications induced during cryopreservation in the structural and functional integrity of cell membranes. For this, the evolution of electrolyte leakage, lipid peroxidation products and cell membrane protein contents was measured during 5 d after cryopreservation. Differences between control and frozen calluses were observed only during the first 2 (electrolyte leakage) or 3 d (lipid peroxidation products and membrane protein content) after freezing. It was not possible to link these differences with the differences noted in survival and plant production between control and cryopreserved calluses. Additional studies are thus needed to elucidate which biochemical factors, linked to survival and plantlet regeneration, are affected by cryopreservation. 相似文献
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The time integration of strain rate tensor is a central problem in large transformations even if it is often an underlying one. The cumulated tensorial strains, obtained by the time integration of strain rate tensor , allow the tackling of this problem from a geometrical point of view, and independently of material behaviour considerations. The time integration here takes place in the local objective frame defined by the logarithmic spin proposed by Lehmann et al. and Xiao et al. The numerical results obtained in a closed deformation path are presented here. The advantages and drawbacks of this novel integration for the development of behaviour laws are described. To cite this article: V. Mora et al., C. R. Mecanique 332 (2004). 相似文献