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101.
102.
Ditzler WR Hill D Hoftiezer J Johnson KF Lopiano D Shima T Shimizu H Spinka H Stanek R Underwood D Wagner RG Yokosawa A Burleson GR Faucett JA Fontenla CA Garnett RW Luchini C Rawool-Sullivan MW Bhatia TS Glass G Hiebert JC Kenefick RA Nath S Northcliffe LC Damjanovich R Jarmer JJ Vaninetti J Jeppesen RH Tripard GE 《Physical review D: Particles and fields》1992,46(7):2792-2830
103.
A. Malki J. P. Coffin G. Guillaume F. Jundt K. Krishan F. Rami P. Wagner P. Fintz M. Zahar M. Gonin B. Heusch M. Ohta B. Rastegar D. Rebreyend F. Merchez J. Mistretta S. Kox 《Zeitschrift für Physik A Hadrons and Nuclei》1991,339(2):283-292
In an attempt to separate preequilibrium and thermalised emissions of light particles in low impact parameter heavy-ion collisions, the40Ar+24Mg reaction has been studied at 27.5 MeV/nucleon. Exclusive measurements have permitted us to examine, in some detail, heavy fragments and charged particles (p, d, t,-particle). The fragments recognized as evaporation residues have been selected and, due to inverse kinematic conditions, the related preequilibrium and statistical emissions of light particles resulting from incomplete fusion reaction appear to be distinguishable to a fair extent. This separation is fully supported by Monte Carlo calculations. Some experimental characteristics of the light particles have been examined and compared to the predictions of dynamical calculations. These calculations, associating a preequilibrium (interpreted as prompt emitted particles) model with a statistical-decay model, follow the evolution of the collision from the point of contact between the projectile and the target to the final evaporation-residue formation on an event by event basis. The predictions of these calculations have been compared to experimental data and satisfactory agreement is achieved for fragment-mass distribution, proton-energy spectra, and proton-angular distribution. 相似文献
104.
F. Heine T. Faestermann A. Gillitzer J. Homolka M. Köpf W. Wagner 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(2):225-226
In fusion reactions of58Ni beams with54Pe and58Ni target nuclei neutron deficient evaporation residues have been produced and separated from the beam in an electrostatic deflector with large acceptance. The recoil nuclei were implanted and detected in an array of 100 PIN photodiodes, where also their particle decays were recorded. The assignment of the 0.81 MeV proton line to the decay of109I could be experimentally proven by the observation, that it is followed by the 3.31 MeV alpha emission from108Te. A proton decay from112Cs was not observed. The decay energies of a number of known emitters have been measured with better precision.Dedicated to Prof. Dr. P. Kienle on the occasion of his 60th birthday 相似文献
105.
J. Döring L. Funke W. Wagner G. Winter 《Zeitschrift für Physik A Hadrons and Nuclei》1991,339(3):425-426
Excited states in the doubly-odd nucleus82Rb have been investigated via the reactions79Br(,n) and78Se(7Li,3n) using in-beam-ray spectroscopy. The level energy of the longlived 5– isomer has been determined to 68.3 keV which is below the energy of the 2– state found at 88.9 keV with a lifetime of=2.4(2) ns. A sequence of positive-parity states beginning with a 6+ level at 191.3 keV (=20(3) ns) and extending to a (10+) level has been interpreted to contain the two-particle configuration (g
9/2
9/2) and collective excitations. 相似文献
106.
107.
Wagner J. Barreto Henrique de Santana Flaveli A. S. Almeida Dilson N. Ishikawa Yoshio Kawano 《Journal of Analytical and Applied Pyrolysis》2003,70(2):719-210
The synthesis, characterization, and thermal decomposition of the [Ni(SCN)2(H+SCN)2(4-mepy)2] compound with an octahedral structure in polymeric chain were reported, in which SCN groups form bridges among Ni(II) ions. The compound decomposes in water resulting in a pH<4 solution. The FT-IR spectrum presented doublet bands at 2117; 2128 cm−1, 788; 773 cm−1 assigned to ν(C---N) and ν(C---S) stretching modes, respectively, and δ(SCN) deformation modes at 468; 476 cm−1. The Raman spectrum of the compound presented the ν(C---N) stretching as a strong doublet at 2122; 2128 cm−1, ν(C---S) at 783; 770 cm−1, and δ(SCN) at 468; 477 cm−1. No significant changes were observed in the 4-mepy ligand bands compared with the vibrational frequencies of the pure compound or the compound in aqueous solution 0.2 mol l−1. The crystal UV–vis reflectance spectrum presented two bands centered in 626 and 424 nm tentatively assigned to the d→d type transitions, 3A2g→3T1g and 3A2g→3T1g, for a symmetry close to Oh. The TG curve showed a mass loss between 120 and 200 °C assigned to the loss of the two 4-mepy molecules; from 200 to 265 °C, the loss of the two H+SCN groups; and from 265 to 450 °C, the loss of the two SCN groups that formed the bridges among the nickel atoms. Based on these mass loss data, a mechanism of thermal decomposition for the compound was proposed. 相似文献
108.
[reaction: see text] Rhodium-catalyzed oxygen transfer was used to generate benzyl 2-silyl-2-oxoacetates in good yields. The hydrogenation of these compounds led to chiral alpha-silyl-substituted alpha-hydroxyacetic acids. Resolution by means of HPLC using a chiral stationary phase afforded an enantiomerically pure representative of this class of compounds, which was successfully applied as a chiral ligand in an asymmetric aldol-type reaction. 相似文献
109.
The EPR single-crystal and powder spectra of mixed crystals of (3-chloroanilinium)(8)(Cd(1-x)Cu(x)Cl(6))Cl(4) are measured as a function of temperature and x and analyzed with respect to the geometry and bonding properties of the CuCl(6) polyhedra. These undergo strong distortions due to vibronic Jahn-Teller coupling, with the resulting tetragonal elongation being superimposed by a considerable orthorhombic symmetry component induced by a host site strain acting as a compression along the crystallographic a axis. This strain becomes apparent in the cadmium compound (x = 0), whose crystal structure is also reported [a = 8.701(2) ?, b = 13.975(2) ?, c = 14.173(2) ?, alpha = 81.62(1) degrees, beta = 72.92(1) degrees, gamma = 77.57(1) degrees, triclinic P&onemacr;, Z = 1]. A calculation of the ground state potential surface and its vibronic structure nicely reproduces the g values, Cu-Cl spacings, and ligand field data. At high copper concentrations (including x = 1), the CuCl(6) polyhedra are coupled elastically, with the long axes of neighboring polyhedra having perpendicular orientations. The elastic correlation presumably is not of the long-range antiferrodistortive type, however. Above about 55 K, the angular Jahn-Teller distortion component becomes dynamically averaged within the time scale of the EPR experiment, leading to local tetragonally compressed CuCl(6) octahedra. 相似文献
110.
B. K. Wagner P. E. Garrett Minfang Yeh S. W. Yates 《Journal of Radioanalytical and Nuclear Chemistry》1997,219(2):217-220
The first excited state of137Ba has been excited by the inelastic scattering of accelerator-produced neutrons. The energy of this state at 283.5 keV is not in agreement with the generally accepted value of 279.2 keV, but is in accord with other recent measurements. No evidence for a doublet of states near this energy is found. 相似文献