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P. J. J. Kok J. B. M. de Haas K. Abrahams H. Postma W. J. Huiskamp 《Zeitschrift für Physik A Hadrons and Nuclei》1986,324(3):271-281
Theγ-radiation from the10B(n,γ) reaction is studied using an unpolarized target. More accurate values for energies of transitions in11B could be determined. No new levels have been found. TheQ value of this reaction: 11,454.1 (2)keV, is in agreement with earlier experiments. Also a new value for the cross section could be derived: 0.29 (4) barn, which is a factor 5 more accurate than earlier experiments. The10B(n, α)7 Li reaction, leading to the 478 keV state in7Li, is studied by means of polarized10B nuclei and polarized neutrons. The resulting anisotropy in the directional distribution of the7Li particles manifests itself in the Doppler broadening of the 478 keV line. Analysis of the line shape directly yields the conclusion, that the reaction proceeds for more than 96% through theJ=7/2 channel of11B in case of destructive channel interference of theJ=5/2 channel. Constructive channel interference is only possible if the reaction proceeds for more than 99.5% through theJ=7/2 channel. It appeared that the outcomingα and7Li particles are emitted predominantly in directions perpendicular to the nuclear orientation axis. 相似文献
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Thom F. Oostendorp Adriaan van Oosterom Geertjan Huiskamp 《Journal of computational physics》1989,80(2)
An interpolation method for scalar functions on a rectangular grid on a planar surface is extended to the interpolation function on a closed three-dimensional triangulated surface of arbitrary shape. Two variants are considered. The first one constrains the Laplacian of the function to be zero at points where the function values are unknown. The second one minimizes the Laplacian at all points of the surface considered. Some illustrative examples of both variants are given in applications to the display of potential distributions on the boundary surface of an electrical volume conductor. 相似文献
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J.B.M. de Haas K. Abrahams T.A.A. Tielens H. Postma W.J. Huiskamp 《Nuclear Physics A》1984,419(1):101-114
Circular polarization of γ- radiation following capture of polarized thermal neutrons by unoriented nuclei and the angular distribution of such radiation, using polarized neutrons and polarized nuclei, made it possible to assign spins to 13 levels of 52V. In addition the admixtures of spin-3 and spin-4 reaction channels could be derived for 20 primary γ-ray transitions. With this information interference phenomena in the 51V(n, γ) reaction were studied. The low-lying levels of 52V are compared with shell-model calculations. The capture mechanism is discussed in terms of a doorway-state model. 相似文献
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Hoeben W. F. L. M. van Ooij P. P. Schram D. C. Huiskamp T. Pemen A. J. M. Lukeš P. 《Plasma Chemistry and Plasma Processing》2019,39(3):597-626
Plasma Chemistry and Plasma Processing - Plasma activated deionized water from a hot arc 150 W PAW synthesizer has been analyzed for nitrite, nitrate and peroxide densities. Observed nitrite and... 相似文献
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G. Mennenga L.J. de Jongh W.J. Huiskamp J. Reedijk 《Journal of magnetism and magnetic materials》1984,43(1):3-12
We present specific heat data on the system FepZn1-pL6(ClO4)2, which is an experimental realization of the sc, , diluted Ising antiferromagnet. Here L = C5H5NO. The results are compared with earlier data on the diluted sc, , XY antiferromagnet CopZn1-pL6(Cl)4)2 and the diluted bcc, , Ising antiferromagnet CopZn1-pCs3Cl5. The specific heat behaviour of the diluted Ising systems is found to be completely different from that of the diluted XY magnet, for which very strong short-range order effects have been observed. An explanation is given in terms of the fractal properties of the infinite percolation cluster in the temperature range above Tc(p). It is shown that there exists a strong analogy between the specific heat behaviour of a diluted magnet and that of a system of weakly coupled magnetic chains. In this picture a decrease of p corresponds with a decrease of the coupling between the chains. The differences in behaviour observed between the Ising systems on the one hand, and the (isotropic) XY or Heisenberg systems on the other, can then be explained by the fact that the intrachain correlation length depends exponentially on temperature for the Ising chain, whereas it depends much less strongly on temperature (∝ 1/T) for the XY and Heisenberg chains. 相似文献
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W. van Rijswijk F. G. van den Berg W. R. Joosten W. J. Huiskamp 《Hyperfine Interactions》1983,15(1-4):325-328
NMR/ON measurements on141CeFe show the sign of the hyperfine field of CeFe to be negative. For the141Ce nucleus a g-factor of ¦gN¦=0.311±0.011 is found. With this g-value a hyperfine field of Hhf=?41±2 T for CeFe is derived. Low temperature nuclear orientation experiments on141CeCo and140LaFe yield ¦Hhf¦=30±3 T and ¦Hhf¦=46±5 T respectively. The valence of cerium impurities in Fe, Co and Ni is discussed. 相似文献
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F. G. Van Den Berg W. Van Rijswijk W. R. Joosten W. J. Huiskamp 《Hyperfine Interactions》1985,22(1-4):579-584
Low temperature nuclear orientation experiments down to 2 mK on147GdFe,149GdFe,149GdGd and153GdGd have yielded the magnetic hyperfine interaction strength. Bhf as 31.0(1.6) NT, 28.3(2.0) NT, 33.8(4.7) NT and 13.3(2.1) NT respectively. From these values the respective ground state magnetic moments ¦¦ of147Gd,149Gd and159Gd were deduced as 1.12(20) N, 1.01(16) N and 0.40(8) N. 相似文献
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In γ-picoline a minimum in the proton spin lattice relaxation time is found at 1/T = 0.44 K-1, suggesting a nearly free methyl group ratation. 相似文献