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31.
Iori Fukushima 《Tetrahedron letters》2007,48(10):1855-1858
2,2-Dilithiocyanocyclopropanes were easily generated from 2-bromo-2-(p-tolylsulfinyl)cyanocyclopropanes with tert-butyllithium in toluene at −78 °C through concomitant sulfoxide-lithium and bromine-lithium exchange reactions. The gem-dianions were found to be stable at −78 °C for at least 30 min. Reaction of the gem-dianions with electrophiles gave fully substituted cyanocyclopropanes in moderate yields. 相似文献
32.
Enzymatic desulfation of stable glucoraphenin affords desulfoglucoraphenin, which unexpectedly undergoes further transformations into cyclic nitrone-type derivatives. 相似文献
33.
In the two-dimensional single large object placement problem, we are given a rectangular master surface which has to be cut into a set of smaller rectangular items, with the aim of maximizing the total value of the pieces cut. We consider the special case in which the items cannot be rotated and must be cut with their edges always parallel to the edges of the surface. We present new greedy algorithms and a hybrid genetic approach with elitist theory, immigration rate, heuristics on-line and tailored crossover operators. Extensive computational results for a large number of small and large benchmark test problems are presented. The results show that our approach outperforms existing heuristic algorithms. 相似文献
34.
M. D'Agostino M. Bruno F. Gramegna I. Iori P. F. Mastinu P. M. Milazzo E. Plagnol G. Vannini 《Zeitschrift für Physik A Hadrons and Nuclei》1995,353(2):191-196
Correlations between Intermediate Mass Fragments were measured for the reaction Xe + Cu atE/A= 45 MeV/u. The velocity correlation function for central 3-fold events, depleted at small values of the relative coordinate, as typical for fast decay processes, reflects the mutual Coulomb repulsion between the emitted fragments. From the comparisons between a significant number of experimental observables and the predictions of the Berlin Multifragmentation Model, it appears that the data are compatible with a simultaneous multifragment emission. 相似文献
35.
36.
Sapienza P Coniglione R Colonna M Migneco E Agodi C Alba R Bellia G Del Zoppo A Finocchiaro P Greco V Loukachine K Maiolino C Piattelli P Santonocito D Ventura PG Blumenfeld Y Bruno M Colonna N D'Agostino M Fabbietti L Fiandri ML Gramegna F Iori I Margagliotti GV Mastinu PF Milazzo PM Moroni A Rui R Scarpaci JA Vannini G 《Physical review letters》2001,87(7):072701
The energetic proton emission has been investigated as a function of the reaction centrality for the system (58)Ni + (58)Ni at 30A MeV. Extremely energetic protons (E(NN)(p) > or = 130 MeV) were measured and their multiplicity is found to increase almost quadratically with the number of participant nucleons, thus indicating the onset of a mechanism beyond one- and two-body dynamics. 相似文献
37.
G. D'Erasmo L. Fiore A. Pantaleo I. Iori Li Zu Yu A. Moroni F. Gramegna M. Pavanati G. Prete R. A. Ricci G. Viesti 《Zeitschrift für Physik A Hadrons and Nuclei》1985,321(3):425-428
The element distributions for the reactions32S+100Mo,32S+93Nb, and28Si+93Nb have been measured atE/B~1.4. The correlations between the first moment of the measured distributions and TKEL are consistent with the predictions of the liquid drop potential energy surfaces showing the charge equilibration of the dinuclear systems. The measured second moments are compared with a recent systematics. 相似文献
38.
39.
Mauro Dell’Amico Manuel Iori Silvano Martello Michele Monaci 《Journal of Heuristics》2012,18(6):939-942
A recent paper (Davidovi? et al., J. Heuristics, 18:549?C569, 2012) presented a bee colony metaheuristic for scheduling independent tasks to identical processors, evaluating its performance on a benchmark set of instances from the literature. We examine two exact algorithms from the literature, the former published in 1995, the latter in 2008 (and not cited by the authors). We show that both such algorithms solve to proven optimality all the considered instances in a computing time that is several orders of magnitude smaller than the time taken by the new algorithm to produce an approximate solution. 相似文献
40.
Ui I Okajo A Endo K Utsumi H Matsumoto K 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2006,181(1):107-112
Methods proposed for in vivo redox status estimation, X-band (9.4 GHz) electron paramagnetic resonance (EPR) bile flow monitoring (BFM) and 300 MHz in vivo EPR measurement, were compared. The spin probe 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (carbamoyl-PROXYL) was utilized for both methods, due to its suitable lipophilicity. EPR signal decay of a nitroxyl spin probe in the bile flow and in the liver region (upper abdomen) of several rat groups with different selenium status were measured by both the BFM and the in vivo EPR method, respectively. The nitroxyl radical clearance measured with in vivo EPR method may be affected not only by the redox status in the liver but also by information from other tissues in the measured region of the rat. On the other hand, the time course of nitroxyl radical level in the bile flow of rats was found to be a reliable index of redox status. Measurement site and/or volume limitation, which was achieved by the BFM method in this paper, is quite important in estimating reasonable EPR signal decay information as an index of tissue/organ redox status. 相似文献