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71.
V. Errico A. Salhi C. Giordano M. De Giorgi A. Passaseo M. De Vittorio 《Superlattices and Microstructures》2008,43(5-6):507
In this work, the analysis, fabrication and optical characterization of a two-dimensional circular photonic crystal (2D-CPC) nano-resonator based on an air/GaAs/air slab waveguide are presented. Four InAs/InGaAs quantum dots (QDs) stacked layers emitting around 1300 nm at room temperature were embedded in a GaAs waveguide layer grown on an Al0.7Ga0.3As layer and GaAs substrate. The patterning of the structure and the membrane release were achieved by using electron beam lithography, ICP plasma etching and selective wet etching of the AlGaAs sacrificial layer. The micro-luminescence spectrum recorded from the fabricated nano-cavity shows a narrow optical transition at the resonance wavelength of about 1282 nm with a FWHM and Q-factor of 6.2 Å and more than 2000, respectively. 相似文献
72.
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
73.
74.
Shaginyan V. R. Msezane A. Z. Clark J. W. Japaridze G. S. Leevik Y. S. 《JETP Letters》2020,112(10):657-665
JETP Letters - In this brief review, we address manifestations of the T/B scaling behavior of heavy-fermion (HF) compounds, where T and B are the temperature and magnetic field, respectively. Using... 相似文献
75.
Thickness dependence of thermally induced changes in surface and bulk properties of Nafion® nanofilms
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Devproshad K. Paul Hyun Ki Shim Javier B. Giorgi Kunal Karan 《Journal of Polymer Science.Polymer Physics》2016,54(13):1267-1277
Thermally induced changes in surface wettability, dewetting behavior, and proton transport of “self‐assembled” nanothin Nafion® films (4–300 nm) on SiO2 substrate is reported. Thermal annealing induces switching of the surface wettability of 55 nm and thinner films from hydrophilic to super‐hydrophobic. Thickness dependence of this behavior is observed with higher annealing temperature required for lower thickness films, indicating highly restrictive mobility of Nafion® ionomer as film thickness decreases. Dewetting is only observed for 4‐nm thin film. Significant suppression in proton conductivity upon thermal annealing was noted. Similarly, two other bulk properties, water uptake and swelling, were found to decrease upon annealing. This work reports a systematic examination of the thickness dependence of thermally induced changes in both surface and bulk properties of ultra‐thin Nafion®. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1267–1277 相似文献
76.
Lucia Giorgetti Gianluca Giorgi Edoardo Cherubini Pier Giovanni Gervasi Clara Maria Della Croce Vincenzo Longo 《Natural product research》2018,32(14):1617-1626
We report the spectrophotometric determination of total polyphenols, flavonoids, glucosinolates and antioxidant activity in seeds, seedlings and leaves of Tuscan black kale. The highest content of phytochemicals was observed in 10 days sprouts and antioxidant activity was maximum in 2, 4 days seedlings. Identification and characterisation of phytochemicals were performed by mass spectrometry (MS), high resolution and tandem MS with electrospray ionisation mode. Low-molecular-weight metabolites were evidenced in seeds while metabolites at high m/z range were detected in cotyledons and leaves. MS spectra evidenced different phenolic compounds (flavonoid caffeoyl glucose, hydroxycinnamic acid sinapine) and glucosinolates (glucoerucin, glucobrassicin and glucoraphanin) in function of developmental stage; galactolipids ω3 and ω6 were observed in leaves. Identification of stages with the highest phytochemicals content encourages the consumption of black kale sprouts and young leaves. Our research can support food and pharmaceutical industries for production of health promoting products from black kale. 相似文献
77.
The structural determination by X-ray crystallography of the titled N-arylamine 4a, as well as AM1 calculations on a series of derivatives (4b–c, 5a–c), are reported. The compound 4a is monoclinic P21/c with a = 7.656(3), b = 23.655(5), c = 7.686(9) Å, = 112.59(6)°, V = 1285.2(2) Å3 and Z = 4. This structure has been used as a template for the building of some others derivatives used for AM1 calculations. The results show that the cyclization position on the aromatic rings, which can lead to two regioisomers, depends on the nature of the benzylic substituants. 相似文献
78.
Attanasi OA Favi G Filippone P Giorgi G Mantellini F Moscatelli G Spinelli D 《Organic letters》2008,10(10):1983-1986
The versatility of the Mukaiyama-Michael-type addition/heterocyclization of Danishefsky's diene with 1,2-diaza-1,3-butadienes was applied to the synthesis of both 4 H-1-aminopyrroles and 4,5 H-pyrazoles. Thus, the same reagents furnished different types of highly functionalized azaheterocycles essentially depending on their structure: as a matter of fact, R1 = COOR or CONR 2 differently affects the acidity of the proton at the adjacent carbon. An unexpected formation of 5 H-1-aminopyrroles from the reactions carried out in water was also observed. 相似文献
79.
Tiziana Giorgi Robert Smits 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2008,59(4):600-618
We consider the principal eigenvalue λ
1Ω(α) corresponding to Δu = λ (α) u in on ∂Ω, with α a fixed real, and a C
0,1 bounded domain. If α > 0 and small, we derive bounds for λ
1Ω(α) in terms of a Stekloff-type eigenvalue; while for α > 0 large we study the behavior of its growth in terms of maximum curvature.
We analyze how domain monotonicity of the principal eigenvalue depends on the geometry of the domain, and prove that domains
which exhibit domain monotonicity for every α are calibrable. We conjecture that a domain has the domain monotonicity property for some α if and only if it is calibrable.
Robert Smits: This author was partially supported by a grant of the National Security Agency, grant #H98230-05-1-0060. 相似文献
80.
Bazzicalupi C Bencini A Bianchi A Borri C Danesi A Garcia-España E Giorgi C Valtancoli B 《The Journal of organic chemistry》2008,73(21):8286-8295
The interaction of the biologically relevant anions deriving from the six pyridinedicarboxylic acids (H2PDC) with two macrocyclic receptors containing a pentamine chain and a bipyridine (1) or a phenanthroline (2) moiety, as well as with the aliphatic analogue [21]aneN7 (3), was studied by means of spectroscopic methods (UV-vis, NMR) and potentiometric titrations affording the stability constants of the adducts formed. All three receptors form stable complexes with the substrates thanks to the formation of several salt bridges and hydrogen bond contacts, as observed in the crystal structure of the H8[3(2,6-PDC)4] x H2O x 0.5 EtOH solid compound. Additional pi-stacking interactions between the aromatic moieties of substrates and receptors enhance the stability of complexes with 1 and 2. Compounds 1 and 2 show a marked selectivity toward 2,6-pyridinedicarboxylate anions. In particular, 1 is able to perform a very efficient recognition of these species in the presence of 2 and 3. Molecular modeling calculations suggested that such recognition ability of 1 can be ascribed to a superior structural and electrostatic complementarity with the substrate compared to 2 and 3. 相似文献