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71.
Barber ZW Giorgetta FR Roos PA Coddington I Dahl JR Reibel RR Greenfield N Newbury NR 《Optics letters》2011,36(7):1152-1154
The optical frequency sweep of an actively linearized, ultrabroadband, chirped laser source is characterized through optical heterodyne detection against a fiber-laser frequency comb. Frequency sweeps were measured over approximately 5 THz bandwidths from 1530 nm to 1570 nm. The dominant deviation from linearity resulted from the nonzero dispersion of the fiber delay used as a reference for the sweep linearization. Removing the low-order dispersion effects, the residual sweep nonlinearity was less than 60 kHz rms, corresponding to a constant chirp with less than 15 ppb deviation across the 5 THz sweep. 相似文献
72.
We provide details for the proof of Fujita's second theorem and prove that for a Kähler fibre space f:X→B over a smooth projective curve B , the direct image of the relative dualizing sheaf V:=f?ωX/B is the direct sum of an ample and a unitary flat bundle. We also show that V needs not be semiample, which is our main result. 相似文献
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74.
Given a totally real field F and a prime integer p which is unramified in F, we construct p-adic families of overconvergent Hilbert modular forms (of non-necessarily parallel weight) as sections of, so called, overconvergent Hilbert modular sheaves. We prove that the classical Hilbert modular forms of integral weights are overconvergent in our sense. We compare our notion with Katz’s definition of p-adic Hilbert modular forms. For F = ?, we prove that our notion of (families of) overconvergent elliptic modular forms coincides with those of R. Coleman and V. Pilloni. 相似文献
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76.
Fabrizio Colombo Graziano Gentili Irene Sabadini 《Annals of Global Analysis and Geometry》2010,37(4):361-378
In this article, we show how to construct a regular, non-commutative Cauchy kernel for slice regular quaternionic functions.
We prove an (algebraic) representation formula for such functions, which leads to a new Cauchy formula. We find the expression
of the derivatives of a regular function in terms of the powers of the Cauchy kernel, and we present several other consequent
results. 相似文献
77.
S Barison C Piccirillo M Fabrizio S Daolio 《Rapid communications in mass spectrometry : RCM》2001,15(21):2014-2019
The electrodeposition of thick gold layers plays an important role both in traditional and high-tech productions, such as jewelry and microelectronics, respectively. In this work a secondary ion mass spectrometric study will be presented on Au co-deposits with (sub-)micrometric ceramic powders, in order to harden gold. Mass spectra are used to identify the components deposited, providing evidence of the additives and/or eventual contaminants introduced during electrolysis. Furthermore, analysis of ion depth profiles and the intensity distribution of ionic species along the film were studied. 相似文献
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The study of the reaction with MeONa/MeOH of chlorinated γ-lactams, prepared from the atom transfer radical cyclization of N-allyl-α-perchloroamides, has been extended to the case of substrates carrying an exo halogen atom on a branched carbon. Only with secondary exo C-Cl groups, that are not located on a fused ring, does the functional rearrangement follow the typical transformation route, which with trichloro-lactams can proceed further to give 4-alkylidene derivatives. From a practical point of view, the outcome of the reaction with di- or trichloro N-cinnamylamides is synthetically valuable, affording the 5-methoxy-1H-pyrrol-2(5H)-one or 3-benzylidenepyrrolidine-2,5-dione, respectively, in good to excellent yield. 相似文献