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1.
Abbotto A Beverina L Bozio R Facchetti A Ferrante C Pagani GA Pedron D Signorini R 《Organic letters》2002,4(9):1495-1498
[structure: see text]. The synthesis and nonlinear optical characterization of two novel heteroaromatic-based chromophores is described. The new dyes present an A-pi-D-pi-A general framework, where A is a pi-deficient heteroaromatic ring (pyridine, quinoline, benzothiazole) and D a pi-excessive pyrrolyl moiety. Both systems exhibit large two-photon absorption (TPA) values in the femtoseconds regime (TPA cross section as high as 150 x 10(-50) cm(4) s photon(-1) molecule(-1) with 150 fs laser pulses). Their TPA-based optical limiting activity is also shown. 相似文献
2.
Abbotto A Beverina L Bozio R Facchetti A Ferrante C Pagani GA Pedron D Signorini R 《Chemical communications (Cambridge, England)》2003,(17):2144-2145
The first examples of heterocycle-based multi-branched dyes with efficient two-photon absorption (TPA) activity are reported; the novel chromophores exhibit large TPA cross sections (as high as 1600 x 10(-50) cm4 s photon(-1) molecule(-1), measured with 150 fs laser pulses at 800 nm); a strong cooperative enhancement in the branched systems with respect to the one-dimensional sub-units is found. 相似文献
3.
Gioria Esteban Signorini Chiara Taleb María C. Thomas Arne Mihályi Magdolna R. Gutierrez Laura 《Cellulose (London, England)》2021,28(14):9135-9147
Cellulose - Palladium was incorporated into carboxymethylated cellulose fibers as a support, thereby becoming an efficient and stable catalyst for low temperature gas phase reaction. Thus, NO was... 相似文献
4.
A lot of methods were created in last decade for the spatio-temporal analysis of multi-electrode array (MEA) neuronal data
sets. In this paper we show how a new simple analysis approach that considers the total network activity, is able to show
interesting neuronal network system dynamical features. In particular, we perform two different analyses: a neuronal connectivity
examination studying networks at different days in vitro (div) and an analysis of the long per- iod effects of the administration of two common neuroactive drugs, Tetrodotoxin (TTX)
and D-2-amino-5-phosphonovalerate (AP5), to spontaneously spiking mature neuronal networks. Our analysis is performed considering
burst topology, i.e., cataloguing network bursts as Global (if they involve more than the 25% of the MEA channels) or Local
(if less that 25%). In the first analysis, this division allows to understand the network connectivity developments. The networking
increases from div 1 to 6 building up an undifferentiated highly connected network. From div 6 to 10 the networking decreases
(pruning) till reaching a plateau in a small-world like organization. The second analysis highlights substantial differences
between long period effects of TTX and AP5. Results show that AP5, selectively blocking NMDA receptors and inhibiting long
term potentiation, is unable to produce activity twisting in a network that already reached a developmental plateau, but it
is able to desynchronize sub-network (Local) activity. TTX, on the other side, blocking any type of electrical communication
among neurons, acts on the whole network synchronization. The important activity increment in the post-TTX epoch (+66%), together
with the Global activity explosion, suggests the possibility of a long-term inhibitory-synapse depression mechanism. 相似文献
5.
T. Faestermann F. Feilitzsch R. S. Raghavan C. Signorini T. Yamazaki C. V. K. Baba D. B. Fossan D. Proetel 《Zeitschrift für Physik A Hadrons and Nuclei》1975,275(2):157-161
Then th,α)-reaction spectroscopical data are reported on95Mo,123Te and145Nd (target nuclei). The95Mo(n, α)92Zr and123Te(n, α)120Sn reactions showed up two lines each corresponding to the ground state and the 1st excited state with a total cross section of 32 ub and 52 μb respectively. In the case of145Nd(n, α)142Ce, a transition only to the 1st excited state of142Ce is present. It is shown that in the case of95Mo,145Nd and probably123Te, most of the cross-section comes respectively from the 2+ possibly 4?, and 0 bound levels whose widths are determined to beΓ α=0.5 × 10?6 eV,Γ α=1.6×10?8 eV andΓ α=1.6 × 10?6 eV. The present results on these three nuclei, when combined with the existing data, are consistent with the calculated statistical model values. 相似文献
6.
7.
P. J. Daly S. Lunardi F. Soramel M. Morando C. Signorini B. Fornal G. Fortuna A. M. Stefanini W. Meczynski 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(2):245-246
A simple evaporation and percolation model is applied to calculate the amount of excitation energy needed to have multifragmentation. 相似文献
8.
A. M. Stefanini Jincheng Xu L. Corradi G. Montagnoli H. Moreno Y. Nagashima L. Mueller M. Narayanasamy D. R. Napoli P. Spolaore S. Beghini F. Scarlassara G. F. Segato F. Soramel C. Signorini H. Esbensen S. Landowne G. Pollarolo 《Physics letters. [Part B]》1990,240(3-4):306-310
Elastic scattering angular distributions have been measured for 58Ni+64Ni at three energies around the Coulomb barrier employing a new kinematic coincidence technique. The data are compared with the results of coupled-channels calculations including inelastic excitations as well as one-and two-neutron transfer reactions. The agreement is good and the calculations also agree well with the available transfer and fusion reaction data. 相似文献
9.
L. Corradi S. J. Skorka U. Lenz K. E. G. Löbner P. R. Pascholati U. Quade K. Rudolph W. Schomburg M. Steinmayer H. G. Thies G. Montagnoli D. R. Napoli A. M. Stefanini A. Tivelli S. Beghini F. Scarlassara C. Signorini F. Soramel 《Zeitschrift für Physik A Hadrons and Nuclei》1990,335(1):55-72
Double differential cross sections of all prominent transfer channels have been measured in the systems33S +99,91,92Zr at two energies close to the nominal Coulomb barrier. In addition the fusion excitation functions of these systems have been measured below and around the barrier. The angular- andQ-distributions of the most important transfer reactions have been analysed in the framework of a simple semiclassical formalism. Particularly the two-nucleon transfer angular distributions exhibit strong multi step coupling effects which manifest themselves in reduced cross sections at large angles corresponding to close distances. From the angular distributions at forward angles, where a single step character of the transfer reaction can be assumed, approximate form factors have been extracted employing a first order perturbation theory. Within the uncertainties of a schematic coupled channels calculation the isotopic differences of the sub-barrier fusion enhancement can be understood on the basis of the isotopic differences of the transfer form factors andQ-values. 相似文献
10.