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排序方式: 共有368条查询结果,搜索用时 15 毫秒
61.
Martinez Vazquez R Osellame R Cretich M Chiari M Dongre C Hoekstra HJ Pollnau M van den Vlekkert H Ramponi R Cerullo G 《Analytical and bioanalytical chemistry》2009,393(4):1209-1216
We use direct femtosecond laser writing to integrate optical waveguides into a commercial fused silica capillary electrophoresis
chip. High-quality waveguides crossing the microfluidic channels are fabricated and used to optically address, with high spatial
selectivity, their content. Fluorescence from the optically excited volume is efficiently collected at a 90° angle by a high
numerical aperture fiber, resulting in a highly compact and portable device. To test the platform we performed electrophoresis
and detection of a 23-mer oligonucleotide plug. Our approach is quite powerful because it allows the integration of photonic
functionalities, by simple post-processing, into commercial LOCs fabricated with standard techniques.
Figure Femtosecond laser written waveguides can selectively excite fluorescence in a microfluidic channel of a commercial lab-on-a-chip.
A compact scheme for on-chip detection by laser induced fluorescence is applied to capillary electrophoresis of a 23-mer Cy3-labeled
oligonucleotide 相似文献
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64.
Dr. Mauro Carraro Dr. Giulia Fiorani Dr. Lorenzo Mognon Dr. Francesca Caneva Dr. Martino Gardan Dr. Chiara Maccato Dr. Marcella Bonchio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(41):13195-13202
Anchoring terminal octenyl tails on molecular polyoxotungstates yield polymerizable organic–inorganic monomers with formula [{CH2?CH(CH2)6Si}xOySiWwOz]4? [x=2, w=11, y=1, z=39 ( 1 ); x=2, w=10, y=1, z=36 ( 2 ); and x=4, w=9, y=3, z=34 ( 3 )]. These molecular hybrids can use aqueous hydrogen peroxide to catalyze the selective oxidation of organic sulfides in CH3CN. Copolymerization of 1 – 3 with methyl methacrylate and ethylene glycol dimethacrylate leads to porous materials with a homogeneous distribution of the functional monomers, as indicated by converging evidence from FTIR spectroscopy and electronic microscopy. The catalytic polymers activate hydrogen peroxide for oxygen transfer, as demonstrated by the quantitative and selective oxidation of methyl p‐tolyl sulfide, which was screened as model substrate. The hybrid material containing monomer 2 was also tested in n‐octane to evaluate its potential for the oxidation and removal of dibenzothiophene, a well‐known gasoline contaminant. 相似文献
65.
Marcella Niglio Cosimo Damiano Vitale 《Methodology and Computing in Applied Probability》2012,14(1):17-34
In this paper the (strict and weak) stationarity of threshold autoregressive moving average models is discussed. After examining
the strict stationarity, mainly based on the random coefficient autoregressive representation of the model, we provide sufficient
conditions for its weak stationarity that allow to obtain a wider stationarity region with respect to some previous results
given in the literature. These conditions are discussed to distinguish between global and local stationarity, whose relation has been considered in detail. The threshold process has been further evaluated to face the
problem related to the so called existence of a threshold structure in the data generating process that is strictly related to the stationarity and has significant
relevance when the parameters of the model have to be estimated. 相似文献
66.
Marcella Pani Angelo Mugnoli Enzo Sottofattori 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):840-842
In the crystal structure of C12H11ClO, the (planar) molecules give rise to a parallel packing. A model crystal obtained by semi‐empirical and packing‐energy calculations is consistent with the observed structure. 相似文献
67.
Enrico DRIOLI Enrica FONTANANOVA Marcella BONCHIO Mauro CARRARO Martino GARDAN Gianfranco SCORRANO 《催化学报》2008,29(11):1152-1158
The design of new heterogeneous photooxygenation systems able to employ visible light, oxygen, mild temperatures, and solvent with a low environmental impact has been investigated. In particular, the heterogenization of decatungstate (W10O4-32), a polyoxometalate with photocatalytic activity in oxidation reactions, has been carried out in polymeric membranes of polyvinylidenefluoride. The polymeric catalytic membranes prepared by phase inversion technique have been successfully applied in the aerobic mineralization of phenol in water, which was used as an example of organic pollutant. In order to evaluate the effect of the polymeric environment on the overall catalyst behavior, we have also heterogenized the decatungstate (opportunely functionalized) in perfluorinated membrane made of Hyflon. The photocatalytic composite membranes are characterized by different and tuneable properties depending on the nature of the polymeric micro-environment, in which the catalyst is confined. Moreover, the selective separation function of the membrane results in enhanced performance in comparison with homogeneous reactions. 相似文献
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R. Bernabei P. Belli F. Montecchia F. Nozzoli F. Cappella A. Incicchitti D. Prosperi R. Cerulli C.J. Dai H.L. He H.H. Kuang J.M. Ma X.D. Sheng Z.P. Ye M. Martinez G. Giuffrida 《The European Physical Journal C - Particles and Fields》2006,47(1):263-271
Galaxy hierarchical formation theories, numerical simulations, the discovery of the Sagittarius Dwarf Elliptical Galaxy (SagDEG)
in 1994 and more recent investigations suggest that the dark halo of the Milky Way can have a rich phenomenology containing
non-thermalized substructures. In the present preliminary study, we investigate the case of the SagDEG (the best known satellite
galaxy in the Milky Way crossing the solar neighborhood) analyzing the consequences of its dark matter stream contribution
to the galactic halo on the basis of the DAMA/NaI annual modulation data. The present analysis is restricted to some WIMP
candidates and to some of the astrophysical, nuclear and particle physics scenarios. Other candidates such as e.g. the light
bosonic ones we discussed elsewhere, and other non-thermalized substructures are not yet addressed here.
PACS 95.35.+d 相似文献