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91.
Lionel Schwartz 《代数通讯》2013,41(5):1825-1845
92.
R. Cicchi L. Sacconi A. Jasaitis R.P. O’Connor D. Massi S. Sestini V. De Giorgi T. Lotti F.S. Pavone 《Applied physics. B, Lasers and optics》2008,92(3):359-365
We have built a custom-made multidimensional non-linear microscope equipped with a combination of several non-linear laser
imaging techniques involving fluorescence lifetime, multispectral two-photon and second-harmonic generation imaging. The optical
system was mounted on a vertical honeycomb breadboard in an upright configuration, using two galvo-mirrors relayed by two
spherical mirrors as scanners. A double detection system working in non-descanning mode has allowed both photon counting and
a proportional regime. This experimental setup offering high spatial (micrometric) and temporal (sub-nanosecond) resolution
has been used to image both ex-vivo and in-vivo biological samples, including cells, tissues, and living animals. Multidimensional
imaging was used to spectroscopically characterize human skin lesions, as malignant melanoma and naevi. Moreover, two-color
detection of two photon excited fluorescence was applied to in-vivo imaging of living mice intact neocortex, as well as to
induce neuronal microlesions by femtosecond laser burning. The presented applications demonstrate the capability of the instrument
to be used in a wide range of biological and biomedical studies.
PACS 87.64.mn; 78.47.Cd; 87.19.lw 相似文献
93.
94.
Ladislav Koudelka Jaroslav Pospíšil Petr Mošner Lionel Montagne Laurent Delevoye 《Journal of Non》2008,354(2-9):129-133
Bulk glasses of the series (1 ? x)[0.5K2O–0.1B2O3–0.4P2O5]–xNb2O5 with x = 0–45.7 mol% Nb2O5 were prepared by slow cooling in air and investigated by Raman, 31P, and 11B MAS NMR spectroscopy. The incorporation of Nb2O5 into the parent borophosphate glass results in a substantial increase in the glass transition temperature and chemical durability of glasses. Raman spectra showed that Nb atoms form distorted NbO6 octahedra, which are isolated at low Nb2O5 content, whereas at higher Nb2O5 content they form clusters. 11B NMR spectra of the glasses revealed the interaction between Nb2O5 and BO4 tetrahedral units, which results in a partial transformation of tetrahedral BO4 units to trigonal BO3 units and the formation of mixed B(OP)4?n(ONb)n units. 相似文献
95.
96.
97.
The photoinduced dynamics of isolated n-hydroxyquinoline (nHQ) molecules (n=6,8) was investigated in femtosecond pump-probe experiments. A qualitative difference was found between 8HQ and 6HQ. After an initial rapid decay corresponding to the departure of the initial wavepacket out of the Franck-Condon region of the excitation, the 8HQ probe signal decays to zero in 0.37 ps whereas a much longer time constant of 10.4 ps is observed in 6HQ. This interrogates on the role played by the intramolecular H-bond N HO which is at play the 8HQ molecule. Ab-initio were performed at the MCSCF/aug-cc-pVDZ level on the 8HQ molecule to help the discussion. A complex energy landscape was found, which includes a conical intersection. 相似文献
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99.
Boisselier E Diallo AK Salmon L Ruiz J Astruc D 《Chemical communications (Cambridge, England)》2008,(39):4819-4821
Gold nanoparticles (AuNPs) are synthesized and stabilized by new "clicked" dendrimers of generations zero to two (G(0)-G(2)) containing tri- and tetra-ethyleneglycol tethers; they are either encapsulated by G(1) (81 tethers) and G(2) (243 tethers) or stabilized without encapsulation by G(0) (27 tethers). 相似文献
100.
After an initial period of validating asymmetric organocatalysis by using a wide range of important model reactions that constitute the essential tools of organic synthesis, the time has now been reached when organocatalysis can be used to address specific issues and solve pending problems of stereochemical relevance. This Review deals with selected studies reported in 2006 and the first half of 2007, and is intended to highlight four main aspects that may be taken as testimony of the present status and prospective of organocatalysis: a) chemical efficiency; b) discovery of new substrate combinations to give new asymmetric syntheses; c) development of new catalysts for specific purposes by using mechanistic findings; and d) applications of organocatalytic reactions in the asymmetric total synthesis of target natural products and known compounds of biological and pharmaceutical relevance. 相似文献