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51.
Mixing and dilution enthalpies of aqueous solutions of 2,3-dimethoxy-5-methyl-1,4-benzoquinone (UQ0) and of N,N-dimethyl-dodecylamine-N-oxide (DDAO) were measured and used to calculate the enthalpies of transfer δH(W →W +S) of UQ0 from water to DDAO aqueous solutions at 20‡, 25‡, 30‡, and 35‡C. From the dependence of δH(W →W +S) on surfactant concentration, the distribution constant between aqueous and micellar phases and the standard transfer enthalpy
of UQ0 from water to DDAO micelles were evaluated along with the standard transfer free energy and entropy. The approach used required
knowledge of the CMC and micellization enthalpy at each temperature. Thus, the thermodynamics of micellization of DDAO was
studied by means of dilution enthalpy measurements at the several temperatures. 相似文献
52.
Ventrella Andrea Verrone Raffaella Cosma Pinalysa Fini Paola Longobardi Francesco Lippolis Vincenzo Pascale Michelangelo Catucci Lucia 《Journal of solution chemistry》2014,43(8):1436-1447
Journal of Solution Chemistry - The interaction of ochratoxin A (OTA) with heptakis-2,6-di-O-methyl-β-cyclodextrin (DIMEB) in aqueous solutions at two different pHs (3.5 and 9.5) was studied... 相似文献
53.
Sumetsky M DiGiovanni DJ Dulashko Y Fini JM Liu X Monberg EM Taunay TF 《Optics letters》2011,36(24):4824-4826
Recently introduced surface nanoscale axial photonics (SNAP) makes it possible to fabricate high-Q-factor microresonators and other photonic microdevices by dramatically small deformation of the optical fiber surface. To become a practical and robust technology, the SNAP platform requires methods enabling reproducible modification of the optical fiber radius at nanoscale. In this Letter, we demonstrate superaccurate fabrication of high-Q-factor microresonators by nanoscale modification of the optical fiber radius and refractive index using CO2 laser and UV excimer laser beam exposures. The achieved fabrication accuracy is better than 2 ? in variation of the effective fiber radius. 相似文献
54.
N. G. Manin A. Fini G. L. Perlovich 《Journal of Thermal Analysis and Calorimetry》2011,104(1):279-289
Solution and dilution enthalpies of aqueous solutions of potassium diclofenac salt (K_DC) were measured by an isoperibolic
calorimeter at 298.15 and 318.5 K. Heat capacities of the solutions with concentrations 0.002–0.09 mol kg−1 were obtained at the temperature interval of 288.15–318.15 K using a scanning adiabatic microcalorimeter. The virial coefficients
were derived from Pitzer’s model, and the excess thermodynamic functions of both the solvent and the solute of the solution
were calculated. The concentration and temperature dependencies of thermodynamic characteristics of the solution were analyzed
and discussed. 相似文献
55.
Chiara Mongioví Dario Lacalamita Nadia Morin-Crini Xavier Gabrion Aleksandra Ivanovska Federico Sala Vincent Placet Vito Rizzi Jennifer Gubitosa Ernesto Mesto Ana Rita Lado Ribeiro Paola Fini Nicoletta De Vietro Emanuela Schingaro Mirjana Kosti Cesare Cosentino Pinalysa Cosma Corina Bradu Gilles Chanet Grgorio Crini 《Molecules (Basel, Switzerland)》2021,26(15)
FINEAU (2021–2024) is a trans-disciplinary research project involving French, Serbian, Italian, Portuguese and Romanian colleagues, a French agricultural cooperative and two surface-treatment industries, intending to propose chènevotte, a co-product of the hemp industry, as an adsorbent for the removal of pollutants from polycontaminated wastewater. The first objective of FINEAU was to prepare and characterize chènevotte-based materials. In this study, the impact of water washing and treatments (KOH, Na2CO3 and H3PO4) on the composition and structure of chènevotte (also called hemp shives) was evaluated using chemical analysis, X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, X-ray computed nanotomography (nano-CT), attenuated total reflectance–Fourier transform infrared (ATR-FTIR) spectroscopy, solid state NMR spectroscopy and thermogravimetric analysis. The results showed that all these techniques are complementary and useful to characterize the structure and morphology of the samples. Before any chemical treatment, the presence of impurities with a compact unfibrillated structure on the surfaces of chènevotte samples was found. Data indicated an increase in the crystallinity index and significant changes in the chemical composition of each sample after treatment as well as in surface morphology and roughness. The most significant changes were observed in alkaline-treated samples, especially those treated with KOH. 相似文献
56.
Vito Rizzi Pinalysa Cosma Ramona Abbattista Paola Fini Angela Agostiano Tommaso R.I. Cataldi Ilario Losito 《Journal of mass spectrometry : JMS》2019,54(5):389-401
The reactivity of the sulfur‐containing nucleoside 4‐thio‐(2′‐deoxy)‐thymidine usually abbreviated as 4‐thio‐thymidine, (S4‐TdR) under Fenton conditions, ie, in the presence of H2O2 and catalytic amounts of Fe(II), was investigated by UV‐vis spectroscopy and electrospray ionization single and tandem mass spectrometry (ESI‐MS and MS/MS). S4‐TdR hydroxylated on the S atom was found to be a key reaction intermediate, ultimately leading to (2′‐deoxy)‐thymidine usually abbreviated as thymidine, (TdR) as the main reaction product. This finding was in accordance with the outcome of the reaction between S4‐TdR and H2O2, previously investigated in our laboratory. On the other hand, the additional presence of ?OH radicals, induced by the Fe(II)/H2O2 combination, led to the increased generation of another interesting S4‐TdR product, already observed after its reaction with H2O2 alone, ie, the covalent dimer including a S? S bridge between two S4‐TdR molecules. More importantly, multihydroxylated derivatives of S4‐TdR and TdR were detected as peculiar products obtained under Fenton conditions. Among them, a product bearing an OH group both on the methyl group linked to the thymine ring and on the C5 atom of the ring was found to prevail. The results obtained during this study, integrated by those found previously in our laboratory, indicate 4‐thiothymidine as a promising molecular probe for the recognition, through a careful characterization of its reaction products, of the prevailing species among reactive oxygen species (ROS) corresponding to singlet‐state oxygen, hydrogen peroxide, and hydroxylic radical. 相似文献
57.
Nicholson JW Yablon AD Yan MF Wisk P Bise R Trevor DJ Alonzo J Stockert T Fleming J Monberg E Dimarcello F Fini J 《Optics letters》2008,33(18):2038-2040
Femtosecond fiber lasers together with nonlinear fibers are compact, reliable, all-fiber supercontinuum sources. Maintaining an all-fiber configuration, however, necessitates pulse compression in an optical fiber, which can lead to nonlinearities for subhundred femtosecond, nanojoule pulses. In this work we show that using large-mode-area fibers for pulse compression mitigates the nonlinearity, resulting in compressed pulses with significantly reduced satellite pulses. Consequently, supercontinua generated with these pulses are shown to have as much as a 10 dB increase in coherence fringe contrast. By using a hybrid highly nonlinear fiber-photonic crystal fiber, the continuum can be extended to visible wavelengths while still maintaining high coherence. 相似文献
58.
S. Ramachandran J.M. Fini M. Mermelstein J.W. Nicholson S. Ghalmi M.F. Yan 《Laser \u0026amp; Photonics Reviews》2008,2(6):429-448
This paper describes the physics and properties of a novel optical fiber that would be attractive for building high‐power fiber lasers and amplifiers. Instead of propagating light in the fundamental, Gaussian‐shaped mode, we describe a fiber in which the signal is forced to travel in a single, desired higher order mode (HOM). This provides for several advantages over the conventional approach, ranging from significantly higher ability to scale mode areas (and hence laser powers) to managing dispersion for ultra‐short pulses – a capability that is practically nonexistent in conventional fibers. Particularly interesting is the fact that this approach challenges conventional wisdom, and demonstrates that for applications requiring meter‐length fibers (as in high‐power lasers), signal stability actually increases with mode order. Using this approach, we demonstrate mode areas exceeding 3200 μm2, and propagate signals with negligible mode distortions over up to 50‐meter lengths. We describe several pulse propagation experiments in which we test the nonlinear response of this fiber platform, ranging from managing dispersive effects in femtosecond pulse systems, to reducing Brillouin scattering impairments in systems operating with the nanosecond pulses. 相似文献
59.
Microchimica Acta - Untersuchungen über die Bestimmung organischen Schwefels bei Anwesenheit von Phosphor wurden durchgeführt, um ein Verfahren auszuarbeiten, das die störenden... 相似文献
60.
Fini P Longobardi F Catucci L Cosma P Agostiano A 《Bioelectrochemistry (Amsterdam, Netherlands)》2004,63(1-2):107-110
The interaction of Rose Bengal (RB) in aqueous solution of LiClO4 0.1 M with alpha-cyclodextrin (alpha-CD), hydroxypropyl-beta-cyclodextrins (HP-beta-CD) and hydroxypropyl-gamma-cyclodextrins (HP-gamma-CD) were studied by spectrophotometric measurements. The presence of Induced Circular Signals and the results of the analysis of the modifications in the absorbance spectra of RB produced by the presence of CDs in solution indicate that RB forms inclusion complexes only with HP-beta-CD and with HP-gamma-CD. 相似文献