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891.
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   
892.
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   
893.
894.
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   
895.
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   
896.
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   
897.
The state of fimbriae type 2 (Fim 2) and fimbriae type 3 (Fim 3) preparations from Bordetella pertussis were examined by negative stain electron microscopy. Uranyl acetate induced clumping of Fim 3 regardless of pH and was unsuitable as a stain for establishing the state of fimbriae. Both ammonium molybdate and sodium phosphotungstate were able to show the differences in Fim 3 stored at pH 7.2 and pH 9.5.  相似文献   
898.
TheK conversion coefficients of the 388 and 483 keV transitions in87Sr populated in the decay of87Y have been measured with Ge(Li) and Si(Li) detectors by the NPG method. We find α K values of 0.162 ± 0.010 and 0.00260 ± 0.00013 for the 388 and 483 keV transitions, respectively.  相似文献   
899.
900.
On-line nuclear orientation was performed on70As. Anisotropy data have been obtained at 8.7mK for 29 gamma transitions. Multipole mixing ratios have been extracted for 17 transitions. Our results are in good agreement with existing data for the ten previously measured transitions. Our first time data for the 1496 keV, 2+→2+ γ-ray suggest the 2536 keV level is a good candidate for a mixed symmetry level.  相似文献   
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