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51.
Anthony D. Appelhans John E. Olson David A. Dahl Michal B. Ward Troy A. Robinson James E. Delmore 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):207-209
A new isotope separator has been designed, constructed, and put into routine operation for separation of 133Xe providing a major advancement and significant cost reduction in preparation of this radioactive isotope. The design features and advantages are discussed that expedite high purity separation of relatively small quantities of this isotope. These advantages could be easily used to expedite separation of other shorter-lived radioactive isotopes. 相似文献
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Transport in Porous Media - Electrical geophysical imaging is a widely used noninvasive technology for visualizing porous media at scales larger than individual pores. Originally developed for... 相似文献
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The diffusion of rhodamine-6G dye in ethanol is observed to be inhibited by optical pumping by a cadmium laser. The diffusion process is observed as a function of the solution temperature. The relative difference in diffusion coefficients with and without optical pumping is calculated. The effect is interpreted as being due to a stronger solvent-dye interaction in the first excited singlet state of rhodamine-6G. 相似文献
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Gabriel Navarro Geoffrey R. Robinson 《Proceedings of the American Mathematical Society》2005,133(10):2845-2851
Let be a -block of a finite group . If is a -power for all , then is nilpotent.
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A Photonic Crystal Ring Resonator (PCRR) based Add Drop Filter is designed using two dimensional (2D) square lattice PC silicon rods in air host. The normalized transmission spectra for a single-ring and dual-ring configurations have been investigated using 2D Finite Difference Time Domain (FDTD). The filter characteristics such as coupling efficiency, dropping efficiency, resonant wavelength and Q factor are numerically analyzed for single ring and dual ring PCRR. It is noted that the coupling efficiency, dropping efficiency and Q factor of single ring circular PCRR with scatterer rod are 100%, 100% and 186.75, respectively. The backward dropping is observed in single ring PCRR whereas forward dropping are noticed in dual ring PCRR based ADF. The Photonic Band Gap (PBG) with respect to structural parameters such as the radius of the rod, lattice constant and refractive index difference, and propagation modes in periodic and nonperiodic structure are calculated by Plane Wave Expansion (PWE) method. 相似文献
58.
Methods are developed for finding the number of unlabeled bridgeless or 2-line-connected graphs of any order. These methods are based on cycle index sums, but it is shown how to avoid explicit compution with cycle index sums by using suitable inversion techniques. Similar results are obtained for unlabeled bridgeless graphs by numbers of points and lines, and connected graphs by numbers of points and bridges. Corresponding results for labeled graphs are found as corollaries. When lines or bridges are required as enumeration parameters in the labeled case it is also shown how to obtain improved recurrence relations. The latter appear to have no analog for unlabeled graphs. 相似文献
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In this paper we show that shifts of finite type satisfying a strong topological mixing property are universal models for ergodic measure preserving dynamical systems. 相似文献
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S Robinson 《The Journal of the Operational Research Society》2005,56(6):619-629
Discrete-event simulation is one of the most popular modelling techniques. It has developed significantly since the inception of computer simulation in the 1950s, most of this in line with developments in computing. The progress of simulation from its early days is charted with a particular focus on recent history. Specific developments in the past 15 years include visual interactive modelling, simulation optimization, virtual reality, integration with other software, simulation in the service sector, distributed simulation and the use of the worldwide web. The future is then speculated upon. Potential changes in model development, model use, the domain of application for simulation and integration with other simulation approaches are all discussed. The desirability of continuing to follow developments in computing, without significant developments in the wider methodology of simulation, is questioned. 相似文献