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1.
G. Mascellani L. Liverani A. Prete G. L. Bergonzini P. Bianchini L. Silvestro 《Journal of carbohydrate chemistry》2013,32(8):1165-1177
Abstract The active site of dermatan sulfate (DS) for heparin cofactor II (HCII) was isolated in a fragment obtained by periodate oxidation, borohydride reduction, mild acid hydrolysis, and SE- and SAX-chromatography of beef mucosal and pig skin DS preparations. Characterization by mass spectrometry, one- and two-dimensional NMR spectroscopy, and HPLC analysis of disaccharides, obtained by exhaustive digestion with chondroitinase-ABC, indicates that the fragment has the prevalent structure 1, GalNAc-4SO3-[IdoA-2SO3-GalNAc-4SO3]4-R, where R is CH(CH2OH)CH(COO?)-OH. 1, is the largest DS fragment thus far isolated containing IdoA2SO3 as the only uronic acid. Its lower activity (30%) with respect to the parent polymeric DS is explainable by Tollefsen model, requiring longer polyanionic chains for formation of ternary complex with thrombin. 相似文献
2.
D. Scarpa L. Biasetto S. Corradetti M. Manzolaro A. Andrighetto S. Carturan G. Prete P. Zanonato D. W. Stracener 《The European Physical Journal A - Hadrons and Nuclei》2011,47(3):32
In the framework of the R&D program for the SPES (Selective Production of Exotic Species) project of the Istituto Nazionale
di Fisica Nucleare (INFN), production yields of neutron-rich isotopes have been measured at the Holifield Radioactive Ion
Beam Facility (HRIBF, Oak Ridge National Laboratory, USA). This experiment makes use of the multi-foil SPES target prototype
composed of 7 uranium carbide discs, with excess of graphite (ratio C/U = 4 . 77 isotopes of medium mass (between 72 and 141amu), produced via proton-induced fission of uranium using a 40MeV proton
beam, have been collected and analyzed for the target heated at 2000 ° C target temperature. 相似文献
3.
L. Biasetto M. Manzolaro A. Andrighetto G. Meneghetti S. Carturan P. Zanonato P. Colombo G. Prete 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):517-521
The target is one of the key issues of isotope separation on line (ISOL) facilities. SPES, now under development at LNL-INFN,
is an innovative ISOL facility possessing a target chatacterized by seven separate uranium dicarbide thin disks. The research
on the materials development and target prototyping is discussed in the following. 相似文献
4.
L. Herrera A. Di Prisco J. Carot N. O. Santos 《International Journal of Theoretical Physics》2008,47(2):380-392
A study covering some aspects of the Einstein–Rosen metric is presented. The electric and magnetic parts of the Weyl tensor
are calculated. It is shown that there are no purely magnetic E-R spacetimes, and also that a purely electric E-R spacetime
is necessarily static. The geodesics equations are found and circular ones are analyzed in detail. The super-Poynting and
the “Lagrangian” Poynting vectors are calculated and their expressions are found for two specific examples. It is shown that
for a pulse-type solution, both expressions describe an inward radially directed flow of energy, far behind the wave front.
The physical significance of such an effect is discussed. 相似文献
5.
B. Fornal F. Gramegna W. Meczynski G. Prete R. A. Ricci G. Viesti G. D'Erasmo L. Fiore G. Guarino A. Pantaleo I. Iori A. Moroni P. Blasi F. Lucarelli 《Zeitschrift für Physik A Hadrons and Nuclei》1987,328(2):227-232
The deep-inelastic reaction induced by 143 MeV32S on58Ni have been studied detecting projectile-like fragments (PLF) in coincidence withγ-rays in NaI(TI) scintillators. γ-ray multiplicity and anisotropy have been derived for Zplf=14, 15 as a function of energy loss and/or γ-energy. The information obtained are compared with a discrete γ-line study of the same reaction. The effect of the exit channel selection (ejectileZ, energy loss,E γ) on the γ-observables is discussed in connection with the evidence of a strong PLF γ-emission. 相似文献
6.
G. Viesti B. Fornal F. Gramegna G. Prete R. A. Ricci G. D'Erasmo L. Fiore G. Guarino A. Pantaleo I. Iori A. Moroni P. Blasi F. Lucarelli 《Zeitschrift für Physik A Hadrons and Nuclei》1986,324(2):161-171
The reactions induced by 143 MeV32S on58Ni have been studied detecting discrete γ-rays in coincidence with projectile-like fragments (PLF). Information on PLF excitation probability and sequential decay of target-like fragments (TLF) has been obtained. For the28Si+62Zn outgoing channel at small energy loss (¦Q¦<20 MeV), both PLF and TLF data indicate that thermal equilibrium is not attained. The hypothesis of an equal excitation energy partition between the two reaction fragments does not describe properly experimental TLF data. A dependence of PLF excitation probability on the outgoing channel is found for the two final channels32S+58Ni and28Si+62Zn. The values of the spin alignment parameterP zz, derived for PLF and TLF from measurements ofγ-rays anisotropy, are in disagreement with the expectations of the transport theory for dissipative collisions. 相似文献
7.
A. Saxena D. Fabris G. Prete D. V. Shetty G. Viesti B. K. Nayak D. C. Biswas R. K. Choudhury S. S. Kapoor M. Lunardon S. Moretto G. Nebbia S. Pesente V. Rizzi A. M. Samant M. Barbui E. Fioretto M. Cinausero A. Brondi G. La Rana R. Moro E. Vardaci N. Gelli F. Lucarelli 《Nuclear Physics A》2004,730(3-4):299-315
Pre-scission and post-scission multiplicities of neutrons and alpha particles have been simultaneously measured for the fission-like reactions of 340 MeV 28Si on 232Th. Dynamical model calculations using HICOL code predict that about 90% of the observed events are of quasi-fission type while the remaining 10% are from compound nucleus fission decay. Moving source fits were carried out to the observed neutron and alpha particle spectra, measured at different angles with respect to the fragment directions. The pre-scission and post-scission neutron multiplicities are deduced to be 8.7±2.0 and 9.4±2.0, respectively. The corresponding multiplicity values for alpha particles are found to be 0.22±0.08 and 0.1±0.03. From the measured post-scission neutron multiplicity, it is inferred that about 65±20 MeV of the initial excitation energy remains at scission. This may be compared to the value of 85±30 MeV estimated from PACE2 statistical model calculations, adjusted to reproduce the measured pre-scission neutron multiplicity. From a comparison of the Statistical Model predictions with the measured pre-scission neutron multiplicity, the fission delay is estimated to be of 5+7−3×10−20 s which overlaps with the average duration of fission-like process from the contact to the scission point (2×10−20 s) as determined from HICOL-based dynamical calculations. For the delay time deduced as above, the pre-scission alpha particle multiplicity calculated by the PACE2 code is about a factor two larger than the experimental one, demonstrating the difficulties in modelling the alpha particle emission from highly elongated shapes that characterize the fissioning system from the contact point to scission. 相似文献
8.
S.J.C. Irvine A. Stafford M.U. Ahmed P. Prete R. Berrigan 《Progress in Crystal Growth and Characterization of Materials》1997,35(2-4):177-206
The development of II–VI MOVPE is reviewed, contrasting the narrow bandgap materials with the wide bandgap. Common issues are the need to grow the layers at lower temperatures than their III–V cousins in order to avoid point defects. This means that II–VI MOVPE occurs in a surface kinetic regime for precursor decomposition and has stimulated a lot of research on alternative precursors. The narrow bandgap II–VI growers have settled on dimethyl cadmium (DMCd) combined with diisopropyl telluride (DIPTe) and a liquid Hg source but wide bandgap growers are split between pyrolytic and photo-assisted growth. Recent progress in p-type doping has enabled the demonstration of some new devices, including two colour infrared detectors and the first MOVPE grown green emitting laser structure. The common theme appears to be hydrogen passivation of the Group V dopant and some novel precursor solutions to this problem are discussed. 相似文献
9.
Walter Alexandre Carnielli Carlos Augusto Di Prisco 《Mathematical Logic Quarterly》1993,39(1):461-474
Several types of polarized partition relations are considered. In particular we deal with partitions defined on cartesian products of more than two factors. MSC: 03E05. 相似文献
10.
A. Di Prisco N. Falcón L. Herrera M. Esculpi N. O. Santos 《General Relativity and Gravitation》1997,29(11):1391-1405
The influence of processes occurring before the system relaxes into diffusion, on the evolution of a radiating sphere, is exhibited in a specific example. The luminosity profiles, and consequently the general evolution of the object, are shown to be quite sensitive to the value of relaxation time. 相似文献