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1.
The statistical multi-step direct emission theory formulated by Feshbach, Kerman and Koonin (FKK) was applied to the analysis of 14 MeV (n, n') scattering on 93Nb and Ag. It is concluded that the FKK theory as it stands disagrees with experimental data, because of anomalously large multi-step cross sections due to the resonance-like behaviour of non-DWBA matrix elements which are entered in the calculation.  相似文献   
2.
In the (p,p′) reaction on 130Te, strong excitation of the second 3? state was found at 3.36±0.01 MeV excitation energy. No strong second 3? state was observed in the (p,p′) reaction on 126Te.  相似文献   
3.
The energy levels of92Nb were studied by means of the92Zr(p, nγ) reaction. The deexcitation γ-rays were observed with a high-resolution Ge(Li) detector in the proton energy range 3.00–4.80 MeV in steps of about 25 keV. Many new excited states of 92Nb were populated by this reaction. Excitation energies up to 1.77 MeV were determined with high precision, and a level scheme of 92Nb is proposed. From a Hauser-Feshbach analysis, the γ-decay scheme and other information, the spin-parities of many levels were assigned.  相似文献   
4.
A luminescent porphyrin dye film has been coated onto a transparent separator on the cathode side of a direct methanol fuel cell (DMFC) to visualise clearly oxygen distribution under operating conditions by analysing emission from the dye.  相似文献   
5.
The reactions ATe(p, t)A?2Te have been studied with even-A targets using 51.9 MeV protons. Three or more strongly excited triton peaks were observed in the spectra of the A-2Te nuclei at energies of ≈ 2–3 MeV excitation. Angular distributions are analyzed using DWBA theory. The lowest octupole (3?1) states of five Te isotopes are strongly excited. The lowest 3? state in 120Te is established at 2.09 ±0.02 MeV. The systematics of excitation energies and cross sections for the lowest 5? and 7? states are interpreted by a quasiparticle model.  相似文献   
6.
Precompound angular distribution in inelastic scattering of 14 MeV neutrons are analysed in terms of surface interaction with the higher exciton states taken into account. This model is applied to some (p, α) reactions also.  相似文献   
7.
We describe the capsulation of colloidally templated polythiophene (P3-TAA) arrays with multi-walled carbon nanotubes (MWNTs) after colloidal template electropolymerization. The dissolution of the polystyrene (PS) particle templates, which were assembled via the Langmuir-Blodgett (LB)-like technique, allowed the formation of hollow-shell Janus type arrays.  相似文献   
8.
Differential cross sections for the elastic and inelastic scattering of 14.1 MeV neutrons from 209Bi have been measured with a time-of-flight system which had an energy resolution of 650 keV. For elastic scattering from 209Bi, an optical-model analysis gave the best-fit potential parameters. The absolute cross sections for excitation of collective (2.66 and 4.36 MeV) states are reproduced by the results of distorted-wave calculations under the assumption of a core (208Pb) excitation model using deformation parameters obtained from (p, p') reactions.  相似文献   
9.
Strong L=5 transitions have been found in the (p, p′) reaction on 122,124,126,128,130Te. The possible 25-pole collective motion in Te nuclei is discussed.  相似文献   
10.
β‐Lactams with contiguous tetra‐ and trisubstituted carbon centers were prepared in a highly enantioselective manner through 4‐exo‐trig cyclization of axially chiral enolates generated from readily available α‐amino acids. Use of a weak base (metal carbonate) in a protic solvent (EtOH) is the key to the smooth production of β‐lactams. Use of the weak base is expected to generate the axially chiral enolates in a very low concentration, which undergo intramolecular conjugate addition without suffering intermolecular side reactions. Highly strained β‐lactam enolates thus formed through reversible intramolecular conjugate addition (4‐exo‐trig cyclization) of axially chiral enolates undergo prompt protonation by EtOH in the reaction media (not during the work‐up procedure) to give β‐lactams in up to 97 % ee.  相似文献   
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