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111.
112.
This work is concerned with the acidic properties of the uranyl ion, UO22+, at 75 and 100 °C in 3.6 mol⋅kg−1 LiClO4 aqueous medium. The investigation was carried out with a coulometric-potentiometric technique. Direct and reverse acid-base
titrations were carried out in order to check whether equilibrium had been reached. Moreover, in order to determine whether
or not the solutions were oversaturated, a further check was carried out with fresh saturated hydrolyzed solutions. 相似文献
113.
Geronés M Erben MF Romano RM Védova CO Yao L Ge M 《The journal of physical chemistry. A》2008,112(11):2228-2234
Small penta-atomic molecules like FC(O)SCl and ClC(O)SCl have been analyzed by using both photoelectron spectroscopy (PES) and results derived from the use of synchrotron radiation in the same energy range. For this second experiment total ion yield (TIY), photoelectron photoion coincidence (PEPICO), and partial ion yield (PIY) spectra have been recorded. This set of data together with results obtained by computational chemistry allow us to study electronic properties and the ionization channels of both species. Thus, whereas the photodissociation behavior of FC(O)SCl can be divided into three well-defined energy regions, the fragmentation dynamics of ClC(O)SCl seems to be more complex. Nevertheless, simultaneous evaluation of the PES and valence synchrotron photoionization studies helps to clarify the molecular ionization processes. 相似文献
114.
Di Bussolo V Fiasella A Romano MR Favero L Pineschi M Crotti P 《Organic letters》2007,9(22):4479-4482
Diastereoisomeric D,L-N-Cbz-imino glycal-derived allyl epoxides 5 and 6 have been synthesized, and their addition reactions with alcohols examined. The reactions lead to the corresponding 2,3-unsaturated-aza-O-glycosides through a new, completely regioselective 1,4-addition process which proceeds with complete substrate-dependent stereoselectivity. 相似文献
115.
Fattorusso C Stendardo E Appendino G Fattorusso E Luciano P Romano A Taglialatela-Scafati O 《Organic letters》2007,9(12):2377-2380
A nor-caryophyllane derivative, artarborol, has been isolated from wormwood (Artemisia arborescens) and its stereostructure established by using a combination of chemical derivatization, NMR data, molecular modeling, and quantum-mechanical calculations. In particular, comparison of experimental 13C NMR data with a Boltzmann-weighed average of 13C NMR chemical shifts, calculated by ab initio DFT method, supported the stereochemical assignment. 相似文献
116.
The enthalpy relaxation mechanism of a low molecular weight synthesis of polymethylmethacrylate was investigated by means of calorimetric experiments. The data were analyzed in terms of a kinetic approach treating nonlinearity in a different manner with respect to the Tool-Narayanaswamy-Moynihan model. The relaxation isotherms recorded at four different temperatures were well reproduced by this approach that, however, failed in describing the relaxation asymmetry towards the equilibrium after opposite temperature jumps. A modification of the model was proposed with an additional free parameter accounting for the stretching of the relaxation function. In this way all the experimental data were reproduced fairly well. 相似文献
117.
L. Gialanella F. Strieder L. Campajola A. D'Onofrio U. Greife G. Gyurky G. Imbriani G. Oliviero A. Ordine V. Roca C. Rolfs M. Romano D. Rogalla C. Sabbarese E. Somorjai F. Terrasi H.P. Trautvetter 《The European Physical Journal A - Hadrons and Nuclei》2000,9(3):303-305
The absolute cross section σ (E) of the radiative capture reaction p(7Be,γ)8B at the center-of-mass energy E = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H2 gas. The 8B residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a ΔE-E detector
telescope. The 8B yield was observed concurrently with the 7Be + p elastic scattering yield, relating σ(E) to the Rutherford scattering cross section. The resulting value, σ(E) = 0.41
± 0.11 μb, leads to an S(E) factor at zero energy of S(0) = 16 ± 4 eV b, in fair agreement with recommended values.
Received: 8 February 2000 相似文献
118.
M. Sandoli A. Boiano L. Campajola A. De Rosa A. D'Onofrio G. Inglima M. La Commara A. Ordine D. Pierroutsakou V. Roca M. Romano M. Romoli M. Trotta F. Rizzo F. Amorini S. Tudisco 《The European Physical Journal A - Hadrons and Nuclei》1999,6(3):275-288
We report on the results obtained from the study of the 32S +74Ge deep inelastic reaction at incident energy E= 320 MeV. High-energy γ-rays were detected in an array of 6 seven-pack BaF2 clusters. Coincidence with complex fragments detected in 12 three-stage telescopes ensured the selection of peripheral reaction
events. In order to investigate the pre-equilibrium dipole strength excitation two independent analyses were performed. In
the first analysis the energy spectra of the γ-rays were evaluated in the statistical model framework while in the second
one the γ-ray fragment angular correlation with respect to the nuclear spin vector of the composite system was studied. Both
methods indicate the excitation of dipole strength in the highly deformed dinucleus and provide dipole resonance parameter
sets that are in good agreement with each other.
Received: 24 March 1999 / Revised version: 17 May 1999 相似文献
119.
E. Costanzo A. Cunsolo A. Foti O.Yu. Goryunov M. Lattuada V.V. Ostashko L. Putaggio S. Romano C. Spitaleri A. Tumino D. Vinciguerra Yu Xian 《The European Physical Journal A - Hadrons and Nuclei》1999,5(1):69-75
8Begs coincidences with 12C, 8Begs and α-particles produced in the 12C +12C interaction at 65 MeV have been measured in a wide in-plane angular range. The 3 −8Begs final state is found to be produced, even if poor statistics prevent any identification of the 16O states involved in the first stage of the process. The 8Begs−α and 8Begs−12C coincidence yields are found to be due to 12C and 16O excited states, decaying into the 8Begs+α and 12C +α systems, respectively.
Received: 15 June 1998 / Revised version: 4 December 1998 相似文献
120.
Diana Amorello Fabrizio Ledda Vincenzo Romano Roberto Zingales 《Journal of solution chemistry》2009,38(2):259-263
The determination of the Ti(IV,III) redox couple formal potential in 1 mol⋅dm−3 HCl, 2 mol⋅dm−3 NaCl medium at 25 °C through batch experiments involving the preparation of Ti(IV) and Ti(III) mixtures via the reaction
of Ti(IV) with zinc amalgam, has been carried out with Emf measurements in order to verify the correctness of the previous
value that the authors obtained by a coulometric-potentiometric investigation in the same conditions. The results from the
two independent methods are in good agreement: (9±1) mV by the first method and (9±2) mV by the average batch result. 相似文献