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161.
It is demonstrated for the first time that a number of observed low lying nuclear states in light p-shell nuclei are in fact eigenstates of a two-body hamiltonian which describes the two nucleon system. It is observed that in some heavier p-shell nuclei there appear states which may not be eigenstates of this hamiltonian. 相似文献
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163.
This paper describes the homopolymerisations of isobornyl methacrylate (IBMA) and poly(ethylene glycol) methacrylate (PEGMA) in supercritical carbon dioxide (scCO2) and copolymerisation with methyl methacrylate (MMA). We have used two different stabiliser systems poly(dimethyl siloxane) monomethylacrylate (PDMS-MMA) and Krytox 157FSL, both of which have been shown previously to be highly effective stabilisers for dispersion polymerisation in scCO2. The effect of initiator concentration and copolymer composition is studied. For the copolymerisation of IBMA and MMA, under optimised conditions it is possible to form discrete particles with diameters in the range 1.4-3.6 μm. The PDMS-MMA macromonomer was found to be less effective as a stabiliser, causing particle aggregation due to the low solubility of this stabiliser in the monomers. The copolymers of PEGMA and MMA are also studied. The materials have interesting solubility properties with a transition in solubility from aqueous to organic media on increasing the MMA content. 相似文献
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166.
J.C. Batchelder K.S. Toth C.R. Bingham L.T. Brown L.F. Conticchio C.N. Davids R.J. Irvine D. Seweryniak W.B. Walters J. Wauters E.F. Zganjar J.L. Wood C. DeCoster B. Decroix K. Heyde 《The European Physical Journal A - Hadrons and Nuclei》1999,5(1):49-52
The excitation energies of the single-particle normal and intruder levels in both 183Tl and 187Bi were measured for the first time via the α decay of 187Bi produced in the 97Mo(92Mo,pn)187Bi reaction. The previously unobserved 187Bi ground state (h9/2) to 183Tl ground state (s1/2) α transition was identified, establishing the 187Bi intruder state excitation energy to be 112(21) keV, 70 keV less than that of the same level in 189Bi.
Received: 10 September 1998 / Revised version: 18 December 1998 相似文献
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William T.M. Irvine 《Comptes Rendus Mecanique》2018,346(3):170-174
This contribution to an issue of Comptes rendus Mécanique, commemorating the scientific work of Jean-Jacques Moreau (1923–2014), is intended to give a brief overview of recent developments in the study of helicity dynamics in real fluids and an outlook on the growing legacy of Moreau's work. Moreau's discovery of the conservation of hydrodynamic helicity, presented in an article in the Comptes rendus de l'Académie des sciences in 1961, was not recognized until long after it was published. This seminal contribution is gaining a new life now that modern developments allow the study of helicity and topology in fields and is having a growing impact on diverse areas of physics. 相似文献
169.
The synthesis and electrical characterisation over a range of oxygen partial pressures (10−20 to 1 atm) are reported for the cubic perovskite niobate-titanates Sr1−x/2Ti1−xNbxO3−δ, which are proposed as potential anode materials for solid oxide fuel cells. Single phase samples were observed for 0≤x≤0.4,
and phase purity was retained on annealing at both high and low oxygen partial pressures. Good electrical conductivity was
observed on reduction in low oxygen partial pressures, with a maximum for the sample with 25% Nb (x=0.25), σ=5.6 Scm−1 at 930°C (P (O2)=10−18 atm). For dense samples the higher the Nb content the more resistant the reduced sample was to reoxidation as the oxygen
partial pressure was increased.
Paper presented at the 3rd Euroconference on Solid State Ionics, Teulada, Sardinia, Italy, Sept. 15–22, 1996 相似文献
170.
Several different metal oxides based anode systems are compared to give insight into their cycling behaviour. The simple electrochemical
model for these systems does not usefully predict the ability for a battery to cycle. Pb and Zn oxides cycle less well than
Sn oxides, and show more initial crystallinity. SnF2 and PbF2 cycle less well than SnO and PbO. Cubic SnP2O7 cycles better than the layered polymorph. The nature and structure of the supporting matrix is therefore important in the
ability of the tin oxides to cycle. Any material with observable crystallinity in first cycle, will not cycle well.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献