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Ferranti P 《European journal of mass spectrometry (Chichester, England)》2004,10(3):349-358
In the study of food proteins, the need for accurate protein structural analysis has been acknowledged because of the fact that nucleotide sequencing alone is of limited analytical value if not combined with relevant information regarding the specific protein expressed and the occurrence of phosphorylation, glycosylation and disulphide bridges, and with the modification induced by the technological treatment. Mass spectrometry, whether used alone or to complement the traditional molecular-based techniques has become fundamental to the structural analysis of proteins. It is, moreover, virtually irreplaceable in determining post-translational modifications as conventional methods cannot deliver reliable data. What lies at the root of this methodological breakthrough is the combination of high-resolution separation techniques such as two-dimensional electrophoresis or capillary reverse- phase high-performance liquid chromatography with mass spectrometric analysis, what is termed "proteomic" analysis. Thus, it appears appropriate to state that the new mass spectrometric techniques have been established as a valuable and efficient tool for protein and peptide analysis in complex mixtures, like those from food matrices, enabling us therefore to provide accurate information on molecular weight and also to put forth a structural assessment at a low-picomole level of material. Thus, a series of alternative approaches have been developed based on advanced mass spectrometric analysis in conjunction with classic protein chemistry in order to provide an in-depth view of food protein structure. This review outlines several of these novel methodologies as they apply to structural characterization of food products. 相似文献
3.
In this paper we report the first synthesis of isoxazolidine and isoxazoline-POSS macromers by 1,3-dipolar cycloaddition reactions of vinyl- and styryl-POSS with N-methyl-C-ethoxycarbonylnitrone and ethoxycarbonyl nitrile oxide, promoted by microwave irradiation. The nature of the resulting cycloadducts has been determined by NOE experiments and supported by computational studies at PM3 and DFT B3LYP/6-31G* levels. 相似文献
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Rolf Holderegger Luigi M. Venanzi Fiorella Bachechi Pasquale Mura Luigi Zambonelli 《Helvetica chimica acta》1979,62(7):2159-2167
The preparation of the nucleophile trans-[RuCl(NO)( 1 )], where 1 is the bidentate ligand Ph2PCH2C18CH2PPh2, and of the five-coordinate species [RuCl(CO)(NO)( 1 )], [RuCl(CO)(NO)(Ph2PCH2Ph)2] and [RuCl(NO)( 2 )( 1 )] are reported. The crystal structure of [RuCl(CO)(NO)( 1 )] shows that the coordination around the metal atom is distorted trigonal bipyramidal with the phosphorus atoms in axial positions. The Ru? N? O bond angle is 142.8°. 1H- and 31P-NMR. and \documentclass{article}\pagestyle{empty}\begin{document}$ \tilde \nu $\end{document}NO IR.-data for the above complexes are reported and related to the coordination geometry. 相似文献
6.
(B)-Geometries are incidence structures arising from permutation sets. The present paper studies the automorphism groups of (B)-Geometries. In certain cases these automorphisms yield examples of inversive planes and of subplanes which are embedded in Minkowski planes (chapter 2). In chapter 3 we describe the automorphism groups of the (B)-Geometries arising from the groups PL(2, pn) and AL(1, pn) in their natural representations on the points of the projective and affine line.Dedicated to Prof.Dr. Walter Benz on his 60th birthdayWork done within the activity of G.N.S.A.G.A. of C.N.R. and supported by the 40% grants of M.U.R.S.T. 相似文献
7.
Mariafrancesca Baratta Antonio Tursi Manuela Curcio Giuseppe Cirillo Fiore Pasquale Nicoletta Giovanni De Filpo 《Molecules (Basel, Switzerland)》2022,27(13)
Water decontamination is an important challenge resulting from the incorrect disposal of heavy metal waste into the environment. Among the different available techniques (e.g., filtration, coagulation, precipitation, and ion-exchange), adsorption is considered the cheapest and most effective procedure for the removal of water pollutants. In the last years, several materials have been tested for the removal of heavy metals from water, including metal-organic frameworks (MOFs), single-walled carbon nanotubes (SWCNTs), and graphene oxide (GO). Nevertheless, their powder consistency, which makes the recovery and reuse after adsorption difficult, is the main drawback for these materials. More recently, SWCNT buckypapers (SWCNT BPs) have been proposed as self-standing porous membranes for filtration and adsorption processes. In this paper, the adsorption capacity and selectivity of Pb2+ (both from neat solutions and in the presence of other interferents) by SWCNT BPs were evaluated as a function of the increasing amount of GO used in their preparation (GO-SWCNT buckypapers). The highest adsorption capacity, 479 ± 25 mg g−1, achieved for GO-SWCNT buckypapers with 75 wt.% of graphene oxide confirmed the effective application of such materials for cheap and fast water decontamination from lead. 相似文献
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Carla Ferragina Romolo Di Rocco Potenzo Giannoccaro Pasquale Patrono Lucantonio Petrilli 《Journal of inclusion phenomena and macrocyclic chemistry》2009,63(1-2):1-9
Intercalation compounds such as the ruthenium trisbipyridyl complex in inorganic layered ion-exchangers (α- and γ-zirconium phosphate) have been synthesized using the batch method. There is no loss of bipyridyl ligand from the metal ion during the exchange of the ruthenium trisbipyridyl complex in these host matrices. The materials obtained are thermally stable up to ~330 °C (γ-phase) or ~380 °C (α-phase). The complex decomposition occurs in one or more steps and at ~600 °C the complex decomposition is complete. The X-ray patterns of ruthenium materials show a new phase with an increase in the interlayer distance with respect to the initial phase. Microanalysis measurements confirm the fact that the ruthenium complex is not modified when exchanged and the complex decomposition depends on its position in the host matrices. 相似文献
10.
Geraldo Capannesi Alberto Rosada Maurizio Manigrasso Pasquale Avino 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(1):163-168
In geochemistry, the distribution of the Rare Earth Elements (REEs) in earth crust and mantle allows to understand geochemical
cycles and origin and age of igneous rocks. In this article REEs (Ce, Dy, Eu, La, Nd, Sm, Tb, and Yb), Th and U in ores of
the North-Latium (Bracciano area, Ceriti Mt., Fate Mt., Sabatini Mt., Vulsini Mt., Acqua Rossa basin), have been investigated
for evaluating the extraction feasibility for industrial applications. 107 samples were irradiated in the rotating rack of
the TRIGA Mark II reactor of the R.C. Casaccia (ENEA) at neutron flux of 2.6 × 1012
n × cm−2 × s−1 for 12 h together with primary and secondary standards. The gamma spectrometry measurements were performed after 8 h, 3 and
30 days of decay by means of HPGe detector (FWHM 1.75 keV at 1332.5 keV, peak/Compton ratio 55.1, relative efficiency of 22%)
connected to a multi-channel analyzer. The total REE mean content is 105 μg g−1, ranging widely between 2.23 and 410.5 μg g−1 (average coefficient of variation 112%). A similar behavior is found for Th and U: their average levels are 13.5 and 6.0 μg g−1, respectively. A quite good correlation between REEs and Th (and U) is found for Ceriti Mt. (r
2 > 0.8) whereas for the other areas the correlation is <0.7. The results obtained evidence the low U content in the investigated
locations. 相似文献