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91.
Spatial location of indomethacin associated with unimeric amphiphilic carrier macromolecules as determined by nuclear magnetic resonance spectroscopy 下载免费PDF全文
David E. Orban Alysha Moretti Kathryn E. Uhrich 《Magnetic resonance in chemistry : MRC》2016,54(7):575-583
A combination of nuclear magnetic resonance (NMR) techniques including, proton NMR, relaxation analysis, two‐dimensional nuclear Overhauser effect spectroscopy, and diffusion‐ordered spectroscopy, has been used to demonstrate the spatial location of indomethacin within a unimolecular micelle. Understanding the location of drugs within carrier molecules using such NMR techniques can facilitate rational carrier design. In addition, this information provides insight to encapsulation efficiency of different drugs to determine the most efficient system for a particular bioactive. This study demonstrates that drugs loaded by the unimolecular amphiphile under investigation are not necessarily encapsulated but reside or localize to the periphery or interfacial region of the carrier molecule. The results have further implications as to the features of the unimolecular carrier that contribute to drug loading. In addition, evidence of drug retention associated with the unimolecular surfactant is possible in organic media, as well as in an aqueous environment. Such findings have implications for rational carrier design to correlate the carrier features to the drug of interest and indicate the strong retention capabilities of the unimolecular micelle for delivery applications. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
92.
93.
Federico Moretti Anna Vedda Norberto Chiodini Mauro Fasoli Alessandro Lauria Vitezslav Jary Romana Kucerkova Eva Mihokova Angeloclaudio Nale Martin Nikl 《Journal of luminescence》2012,132(2):461-466
Structural and optical properties of sol–gel silica based glassceramics doped with 0.1 mol% Ce and codoped with Gd at high concentrations, from 5 mol% up to 40 mol%, are investigated and compared to those of analogous samples doped only with Ce. Raman scattering, transmission electron microscopy, and x-ray diffraction reveal the formation of Gd apatite-like silicate (Gd4.67O(SiO4)3) and of Gd pyrosilicate (Gd2Si2O7) nanophases whose morphology and crystallinity depend on the Gd concentration and thermal treatments. Optical absorption measurements demonstrate the role of the densification atmosphere in modifying the charge state of Ce ions. The incorporation of Ce3+ ions in the nanophases is put in evidence by photo- and radio-luminescence results. 相似文献
94.
The great revolution in theoretical fluid mechanics (brought along by the advent of computers in the middle of the century) that replaced search for a formal solution of a general problem with the analysis of evolutions, is in turn threatened by consumerism replacing physical thought with easy, uncontrolled output.Sommario. La grande rivoluzione nello studio della meccanica dei fluidi (conseguente alla nascita dei calcolatori a metà del secolo) consistette nel sostituire alla ricerca formale di una soluzione generale, l'analisi delle evoluzioni fisiche; ma il consumismo imperante minaccia ora di sostituire l'interpretazione fisica con la facile produzione di risultati incontrollati. 相似文献
95.
Ivan A. Velasco-Davalos Mathieu Moretti Mischa Nicklaus Christian Nauenheim Shun Li Riad Nechache Carlos Gomez-Yanez Andreas Ruediger 《Applied Physics A: Materials Science & Processing》2014,115(3):1081-1085
Multiferroic bismuth ferrite (BiFeO3) has attracted considerable attention due to applications related to the bulk photovoltaic effect in which the direction of polarization determines the direction of the photocurrent. Epitaxial thin films are produced by means of techniques that usually require high temperature processes. The hydrothermal method can be seen as an alternative route to obtain highly textured thin films in quantities compatible with batch processing; nevertheless, the structural, dielectric and electric properties are generally affected by the presence of hydrogen and other reaction by-products. In this work, functional and highly textured BiFeO3 films were successfully produced on metallic SrTiO3:Nb (0.5 wt.%) (100) substrates via hydrothermal synthesis. X-ray diffraction (XRD) and Atomic Force Microscopy (AFM) were used to analyze the structural properties of the films. Piezoresponse Force Microscopy (PFM) and Photoconductive Atomic Force Microscopy (Pc-AFM) were used to determine their functional properties. We show the polarization switching and confirm the presence of the bulk photovoltaic effect for the first time in hydrothermally synthesized BiFeO3. 相似文献
96.
Lorenzo Basso Stefano Moretti Giovanni Marco Pruna 《The European Physical Journal C - Particles and Fields》2011,71(8):1724
We investigate the phenomenology of the Higgs sector of the minimal B−L extension of the Standard Model at a future e
+
e
− Linear Collider. We consider the discovery potential of both a sub-TeV and a multi-TeV machine. We show that, within such
a theoretical scenario, several novel production and decay channels involving the two physical Higgs states, precluded at
the LHC, could experimentally be accessed at such machines. Amongst these, several Higgs signatures have very distinctive
features with respect to those of other models with enlarged Higgs sector, as they involve interactions of Higgs bosons between
themselves, with Z′ bosons as well as with heavy neutrinos. In particular, we present the scope of the Z′ strahlung process for single and double Higgs production, the only suitable mechanism enabling one to access an almost decoupled
heavy scalar state (therefore outside the LHC range). 相似文献
97.
Tavani M Marisaldi M Labanti C Fuschino F Argan A Trois A Giommi P Colafrancesco S Pittori C Palma F Trifoglio M Gianotti F Bulgarelli A Vittorini V Verrecchia F Salotti L Barbiellini G Caraveo P Cattaneo PW Chen A Contessi T Costa E D'Ammando F Del Monte E De Paris G Di Cocco G Di Persio G Donnarumma I Evangelista Y Feroci M Ferrari A Galli M Giuliani A Giusti M Lapshov I Lazzarotto F Lipari P Longo F Mereghetti S Morelli E Moretti E Morselli A Pacciani L Pellizzoni A Perotti F Piano G 《Physical review letters》2011,106(1):018501
Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x?rays and γ?rays lasting a few milliseconds or less. We present in this Letter new TGF timing and spectral data based on the observations of the Italian Space Agency AGILE satellite. We determine that the TGF emission above 10 MeV has a significant power-law spectral component reaching energies up to 100 MeV. These results challenge TGF theoretical models based on runaway electron acceleration. The TGF discharge electric field accelerates particles over the large distances for which maximal voltages of hundreds of megavolts can be established. The combination of huge potentials and large electric fields in TGFs can efficiently accelerate particles in large numbers, and we reconsider here the photon spectrum and the neutron production by photonuclear reactions in the atmosphere. 相似文献
98.
G. Carelli N. Ioli J. C. S. Moraes A. Moretti F. Strumia G. E. Annino A. Bertolini 《International Journal of Infrared and Millimeter Waves》1996,17(6):1023-1030
The results described in this work are part of a systematic search for long wavelength laser lines to be used in high magnetic field EPR applications and in plasma diagnostic. Four new far-infrared laser lines of CH2 = CF2 (1,1 difluoroethylene), optically pumped by a waveguide CO2 laser, have been discovered and characterized in wavelength, polarization relative to the pumping radiation and offset relative to the CO2 center frequency. New measurements of polarization and offset of 5 already known laser lines are also reported. A table of all of the known CO2 pumped FIR laser lines from this molecule is given. 相似文献
99.
Stefano Moretti Ramon Muñoz-Tapia Kosuke Odagiri 《The European Physical Journal C - Particles and Fields》1998,4(2):351-362
Heavy flavour tagging provides a broad range of possibilities in testing QCD features at LEP. We present here a study of
4jets events at LEP I where the so-called light gluinos could be directly produced. We show that microvertex techniques offer
a unique chance to exploit simple kinematical distributions in order to optimise the signal coming from gluino production
with respect to the background of ordinary QCD events. Our results indicate that experimental analyses along the lines suggested
here can exclude or reveal the presence of a gluino for masses up to 10 GeV and lifetimes below 10 sec. We also point out that a large fraction of gluino events could decay in configurations carrying large missing energy,
so to escape the usual selection criteria of 4jet samples. In our study, mass effects of quarks and gluinos have been taken
into account exactly. Our results are independent from both the jet algorithm and its resolution parameter.
Received: 25 July 1997 / Revised version: 16 September 1997 / Published online: 20 February 1998 相似文献
100.
D. Pereira J. C. S. Moraes E. M. Telles A. Scalabrin F. Strumia A. Moretti G. Carelli C. A. Massa 《International Journal of Infrared and Millimeter Waves》1994,15(1):1-44
The technique of optical pumping in polar molecules is the most efficient for Far-Infrared (FIR) laser generation, providing also a versatile and powerful tool for molecular spectroscopy in this spectral region. Methanol (CH3OH) and its isotopic varieties are the best media for optically pumped FIR laser, with over thousand lines observed, and the most widely used for investigations and applications. In this sense, it is important organize and make available catalogues of FIR laser lines as complete as possible. Since the last critical reviews of 1984 [1] on methanol and its isotopic varieties [2,3,4], over hundred papers have been published dealing with hundreds of new FIR laser lines. In 1992 a review of FIR laser lines from CH3OH was presented [5]. In this communication we extend this work to the other methanol isotopes, namely CH3OD, CD3OH, CD3OD,13CH3OH,13CD3OH,13CD3OD, CH3
18OH, CH2DOH, CHD2OH and CH2DOD.Work supported by FAPESP, CNPq, FAEP-Brasil, and CNR-Italia 相似文献