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Giuseppe Chidichimo Marcello Longeri Giuseppina Menniti Giovanni Romeo Alida Ferlazzo 《Magnetic resonance in chemistry : MRC》1984,22(1):52-54
The ring mobility of some 1,5-benzodiazepine-2,4-diones and 1,4-benzodiazepin-2-one has been investigated by the temperature dependence of their 1H NMR spectra. The activation parameters have been obtained, and the influence of N-1 substitution on the ring mobility is discussed, taking into account previously reported data for similar compounds. 相似文献
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E. Vardaci A. Di Nitto A. Brondi G. La Rana R. Moro P. N. Nadotchy M. Trotta A. Ordine A. Boiano M. Cinausero E. Fioretto G. Prete V. Rizzi D. Shetty M. Barbui D. Fabris M. Lunardon G. Montagnoli S. Moretto G. Viesti N. Gelli F. Lucarelli G. N. Knyazheva E. M. Kozulin 《The European Physical Journal A - Hadrons and Nuclei》2010,43(2):127-130
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Bianco A Dezzi S Bonadies F Romeo G Scarpati ML Uccella N 《Natural product research》2006,20(5):475-478
Aroma of olive oil is a very complex mixture of components. Analysis of head space of a series of virgin olive oil samples indicate a great variability of volatile substances composition in olives and these data probably should be related to the story of olives after collecting. 相似文献
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Treatment of 2,3-diketo-cholestane (1) with thallium triacetate in acetic acid afforded mainly 3α-carbomethoxy-A-nor-5α-cholestan-2-one (2). Under similar conditions, the 3,4-diketo steroids (3 and 4) underwent extensive rearrangement affording spiro-lactones (9 and 10), in low yields. The structural assignment of the spiro-cholestane derivative was supported by crystallographic X-ray analysis. This product was the result of A and B-ring contractions followed by acid-catalysed cyclization of an unsaturated carboxy intermediate. 相似文献
79.
The potential and benefits of isotope-coded labeling in the context of MS-based glycan profiling are evaluated focusing on the analysis of O-glycans. For this purpose, a derivatization strategy using d0/d5-1-phenyl-3-methyl-5-pyrazolone (PMP) is employed, allowing O-glycan release and derivatization to be achieved in one single step. The paper demonstrates that this release and derivatization reaction can be carried out also in-gel with only marginal loss in sensitivity compared to in-solution derivatization. Such an effective in-gel reaction allows one to extend this release/labeling method also to glycoprotein/glycoform samples pre-separated by gel-electrophoresis without the need of extracting the proteins/digested peptides from the gel. With highly O-glycosylated proteins (e.g. mucins) LODs in the range of 0.4 μg glycoprotein (100 fmol) loaded onto the electrophoresis gel can be attained, with minor glycosylated proteins (like IgAs, FVII, FIX) the LODs were in the range of 80–100 μg (250 pmol–1.5 nmol) glycoprotein loaded onto the gel. 相似文献
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Emilio Turco Katarzyna Barcz Nicola Luigi Rizzi 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2016,67(5):123
In dell’Isola et al. (Zeitschrift für Angewandte Math und Physik 66(6):3473–3498, 2015, Proc R Soc Lond A Math Phys Eng Sci 472(2185):1–23, 2016) pantographic sheets are proposed as a basic constituent for a novel metamaterial. In Part I, see Turco et al. (Zeitschrift für Angewandte Math und Physik, doi:10.1007/s00033-016-0713-4, 2016), two different numerical models are applied in order to design an experimental setup aimed to prove the effectiveness of introduced concept. The aim of this paper is to prove that the Hencky-type model introduced for planar pantographic sheets allows for the correct prediction, in a large range of imposed displacements, of the experimental measurements concerning specimens undergoing coupled bending and extensional deformations. The four-parameter numerical model introduced is shown to have a large range of applicability: Indeed without changing the values of the material parameters previously attributed in simple extensional tests to a specific specimen by a best-fit procedure, it is possible to forecast its behavior in all the considered type of imposed deformations. The measurements performed include the determination of reactive forces exerted by used hard devices, and the numerical modeling is able to predict very carefully quantitatively and qualitatively also this complex aspect of phenomenology, where previously attempted models seem to have failed. 相似文献