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831.
A. F. Kluk Noah R. Johnson J. H. Hamilton 《Zeitschrift für Physik A Hadrons and Nuclei》1972,253(1):1-12
A detailed investigation of the energies and intensities of the γ-rays that depopulate the low spin levels of the β- and γ-vibrational bands of156Gd and the γ-vibrational band of158Gd has been conducted. Both singles and γ-γ coincidence measurements were made on sources of 15-d156Eu and 46-min158Eu by use of large volume, high resolution Ge(Li) detectors. In addition to the γ-band at 1154.09 keV, twoK π=0+ bands were observed in156Gd with band heads at 1049.45 and 1168.11 keV, respectively. The 2+ and 3+ members of the γ-vibrational band in158Gd were observed at 1187.12 and 1265.43 keV, respectively, as well as a newK π=0+ band at 1195.98 keV. A first order perturbational treatment of the branching ratios was applied to both nuclei. In addition, the mixing between the ground state, the β-, and the γ-vibrational bands of156Gd is considered from two approaches, but neither satisfactorily explains all the experimentalB(E2) ratios. 相似文献
832.
833.
J. B. Gupta N. C. Singhal J. H. Hamilton 《Zeitschrift für Physik A Hadrons and Nuclei》1973,261(2):137-142
The weak transitions in the decay of125Sb have been investigated through gamma ray measurements with high resolution X-ray and with large volume Ge(Li) detectors. The 172.6, 178.8 and 198.5 keV gamma rays are confirmed, while others previously reported were not. Accurate intensities were obtained for the stronger transitions. The weighted averages of these intensities which cover the range of 116 to 670 keV are useful for calibration of Ge(Li) systems. 相似文献
834.
835.
Greentree AD Schirmer SG Green F Hollenberg LC Hamilton AR Clark RG 《Physical review letters》2004,92(9):097901
Given a particular quantum computing architecture, how might one optimize its resources to maximize its computing power? We consider quantum computers with a number of distinguishable quantum states, and entangled particles shared between those states. Hilbert-space dimensionality is linked to nonclassicality and, hence, quantum computing power. We find that qutrit-based quantum computers optimize the Hilbert-space dimensionality and so are expected to be more powerful than other qudit implementations. In going beyond qudits, we identify structures with much higher Hilbert-space dimensionalities. 相似文献
836.
The coordination polymer Pb[B(Im)(4)](NO(3))(xH(2)O), constructed by using sodium tetrakis(imidazolyl)borate and lead(II) nitrate solutions, is a layered material with the metal centers facing the interlayer spacing. As in naturally occurring layered minerals, this compound can readily undergo anion exchange and reversible intercalation of solvent water in the solid state with retention of crystallinity. We observed changes in solvent intercalation by (207)Pb solid state NMR (SSNMR) and thermogravimetric analysis (TGA). Stoichiometric exchange of (15)N nitrate for nitrate and iodide for nitrate is monitored by (15)N and (207)Pb SSNMR, and single crystals of the iodide-exchanged material Pb[B(Im)(4)]I were isolated. While the iodide compound can be obtained through facile exchange from the nitrate parent compound, the organic anion benzoate is placed in the interlayer spacing for nitrate under self-assembly conditions and forms an alternating monolayer in Pb[B(Im)(4)](C(6)H(5)COO)(0.5H(2)O). The ion exchange versus self-assembly behavior correlates with the structural differences in the three compounds. In both Pb[B(Im)(4)]I and Pb[B(Im)(4)](C(6)H(5)COO)(0.5H(2)O), the lead sites act as Lewis acids for the iodide and benzoate, respectively. 相似文献
837.
838.
Mono-urea serine derivatives with low molecular weights were prepared in one step and show remarkable self-assembling and gelation properties in water. 相似文献
839.
Hamilton Patti Pollock Jane Englebright Mitchell De Ann F. Vicenzi Angela E. West Bruce J. 《Nonlinear dynamics, psychology, and life sciences》1997,1(4):237-261
In this article, the authors present an overview of the applications of chaos theory and nonlinear dynamics to problems of relevance not only to nurses, but to anyone dealing with human functioning and interaction. These applications have been in the areas of epidemiology, nursing management and physiological functioning. In some cases, the applications were successful in identifying information that would have been overlooked using traditional methods. In other cases, the problems of data collection and analysis, unique to nonlinear dynamics, are still being developed and tested. 相似文献
840.
An electron detector system with a 3 mm × 100 mm2 Si(Li) detector with a cooled FET and vacuum air lock for changing sources was constructed. The absolute efficiency was measured as a function of energy for use in the measurement ofK conversion coefficients. With the Si(Li) and a Ge(Li) detector, theK conversion coefficient of the 320 keV transition in51V was measured to be 0.00156 ± 0.00008 where theK conversion coefficients of the 661 and 279 keV transitions in137Ba and203Tl were used as standards. From absolute detection efficiency measurements, theK conversion coefficients of the 388 and 483 keV transitions in87Sr were measured to be 0.16 ± 0.02 and 0.0024 ± 0.0003, respectively. 相似文献