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121.
Gabriella Leo Laura Cartechini Piero Pucci Antonio Sgamellotti Gennaro Marino Leila Birolo 《Analytical and bioanalytical chemistry》2009,395(7):2269-2280
The identification of proteinaceous components in paintings remains a challenging task for several reasons. In addition to
the minute amount of sample available, complex and variable chemical composition of the paints themselves, possible simultaneous
presence of several binders and contaminants, and degradation of the original materials due to aging and pollution are complicating
factors. We proposed proteomic strategies for the identification of proteins in binders of paintings that can be adapted to
overcome the requirements and difficulties presented by specific samples. In particular, we worked on (1) the development
of a minimally invasive method based on the direct tryptic cleavage of the sample without protein extraction; (2) the use
of microwave to enhance the enzymatic digestion yield, followed by the analysis of the peptide mixtures by nanoLC-MS/MS with
electrospray ionization (ESI). Moreover, as an additional tool to tackle the problem of contaminating proteins, we exploited
the possibility of generating an exclusion list of the mass signals that in a first run had been fragmented and that the mass
spectrometer had to ignore for fragmentation in a subsequent run. The methods, tested on model samples, allowed the identification
of milk proteins in a sample from paintings attributed to Cimabue and Giotto, thirteenth-century Italian masters, decorating
the vaults of the upper church in the Basilica of St. Francis in Assisi, Italy. 相似文献
122.
Maddalena Corsini Piero Zanello Renzo Cini Gabriella Tamasi 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(6):m219-m223
The title compound, [Cu(C10H9N2O)2] or [CuII(CYMB)2], (I), was obtained in an attempt to reduce trans‐bis(2‐{[3,5‐bis(trifluoromethyl)phenyl]iminomethyl}phenolato)copper(II), [Cu(TIMB)2], (II), with bis(pentamethylcyclopentadienyl)cobalt(II) [decamethylcobaltocene, Cp*2Co, (III)]. The molecular structure of (I) has the CuII centre located on an inversion centre of the C2/c space group. A density functional theory (DFT) analysis at the B3LYP/Lanl2dz(CuF);6‐31G**(CHNO) level performed in order to optimize the structures of the free ligands CYMB− and TIMB−, and the metal complexes [CuI/II(CYMB)2]−/0 and [CuI/II(TIMB)2]−/0, reproduced well the X‐ray diffraction structure and allowed us to infer the insertion of the cyanomethide anion on the 3,5‐bis(trifluoromethyl)phenyl system from an evaluation of the Mulliken atomic charges and the electronic energies. 相似文献
123.
The results in our paper heavily rely on the journal version of [T. Brzeziński, A note on coring extensions, Ann. Univ. Ferrara Sez. VII (N.S.) 51 (2005) 15-27; a corrected version is available at http://arxiv.org/abs/math/0410020v3, Theorem 2.6]. Since it turned out recently that in the proof of the quoted theorem there are some assumptions missing, our derived results are not expected to hold at the stated level of generality either. Here we supplement the constructions in our article with the missing assumptions and show that they hold in most of our examples. In order to handle also the non-fitting case of cleft extensions by arbitrary Hopf algebroids, Morita contexts are constructed that do not necessarily correspond to coring extensions. They are used to prove a Strong Structure Theorem for cleft extensions by arbitrary Hopf algebroids. In this way we obtain in particular a corrected form of the journal version of [G. Böhm, Integral theory for Hopf algebroids, Algebr. Represent. Theory 8 (4) (2005) 563-599; Corrigendum, to be published; see also http://arxiv.org/abs/math/0403195v4, Theorem 4.2], whose original proof contains a similar error. 相似文献
124.
Theorem 2.2 stated a monoidal isomorphism between the comodule categories of two bialgebroids in a Hopf algebroid. The proof
of Theorem 2.2 was based on the journal version of Brzeziński (Ann Univ Ferrara Sez VII (NS) 51:15–27, 2005, Theorem 2.6), whose proof turned out to contain an unjustified step. Here we show that all other results in our paper remain
valid if we drop unverified Theorem 2.2, and return to an earlier definition of a comodule of a Hopf algebroid that distinguishes
between comodules of the two constituent bialgebroids. 相似文献
125.
Assume that the elliptic operator L=div (A(x)∇) is L
p
-resolutive, p>1, on the unit disc
\mathbbD ì \mathbb R2\mathbb{D}\subset \mathbb {R}^{2}
. This means that the Dirichlet problem
$\left\{{l@{\quad}l}Lu=0&\mbox{in }\mathbb{D},\\[3pt]u=g&\mbox{on }\partial\mathbb{D}\right.$\left\{\begin{array}{l@{\quad}l}Lu=0&\mbox{in }\mathbb{D},\\[3pt]u=g&\mbox{on }\partial\mathbb{D}\end{array}\right. 相似文献
126.
In a recent paper (Böhm and Stefan, Commun Math Phys 282:239–286, 2008), we gave a general construction of a para-cocyclic structure on a cosimplex, associated to a so called admissible septuple—consisting of two categories, three functors and two natural transformations, subject to compatibility relations. The main examples of such admissible septuples were induced by algebra homomorphisms. In this note we provide more general examples coming from appropriate (‘locally braided’) morphisms of monads. 相似文献
127.
Ortica F Smimmo P Mazzucato U Favaro G Heynderickx A Moustrou C Samat A 《Photochemistry and photobiology》2006,82(5):1326-1333
The photobehavior of five photochromic dipyrrolyl-perfluoro-cyclopentenes was studied by steady state and time-resolved absorption spectroscopy. The quantum yields of the UV-photoinduced ring-closing reaction (coloration) and the visible-stimulated cycloreversion reaction (bleaching) were measured. Kinetic and thermodynamic parameters of thermal bleaching were also determined. Nanosecond time-resolved experiments showed formation of a transient, which was not a precursor of the reaction photoproduct. This transient was tentatively assigned to a radical cation formed by direct photoionization through a short-lived triplet state. The nature of the transient species was supported by photoinduced electron transfer to electron acceptors. 相似文献
128.
Chen C Nagy G Walker AV Maurer K McShea A Moeller KD 《Journal of the American Chemical Society》2006,128(50):16020-16021
Time-of-flight secondary ion mass spectrometry (TOF SIMS) has been used in conjunction with a mass spectrometry cleavable linker to determine the percent conversion of reactions that were conducted site-selectively on an addressable microelectrode array. When combined with fluorescence techniques for analysis of the reactions, the TOF SIMS experiment provides a means for optimization of both reaction confinement and reaction efficiency on the microelectrode arrays. 相似文献
129.
130.
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