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111.
112.
Ng Seik Weng~* 《结构化学》2000,(6)
1 INTRODUCTIONSeveralincorrectspacegroupshavebeenre assignedbymakinguseofsimulatedstructurefactors;however,thecruxofthisoranyspacegrouprevisionistheaccuratereportingofthespacegroupandatomiccoordinatesoftheincorrectlydeterminedstructuresincethetruestruc… 相似文献
113.
Lawrence M. Henling Richard E. Marsh 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(9):834-836
A survey of approximately 100 000 entries in recent releases of the Cambridge Structural Database (CSD) has uncovered 156 crystal structures that were apparently described in inappropriate space groups. We have revised these space groups and prepared CIFs containing the new coordinates and brief comments describing the revisions. 相似文献
114.
115.
F.E. Jones 《International Journal of Heat and Fluid Flow》1984,5(4):247-250
A new method has been developed for estimating the corrections to be made to the measured time interval for diverter valves used in primary liquid flow measurement facilities. The model relates the mass flowrate, m, to the measured mass of liquid collected and the effective collection time. The effective collection time is the sum of the measured time interval and the diverter valve correction, τ, to be estimated. The diverter valve correction is the adjustment made to the collection time to account for the non-instaneous diversion of the flow between the collection vessel and the reservoir of the flow loop. An auxiliary flow measurement device in the flow pipeline is used to estimate m and an iterative process is used in the estimation of τ. This method gives statistical information on the variability of the performance of the system as indicated by the individual estimates of τ. Experimental data for two diverters used in the US National Bureau of Standards Primary Liquid Flow Measurement Facility are used to illustrate the calculation procedure 相似文献
116.
The present paper numerically investigates the near-wall correction of velocity readings when using hot wires to measure the flows very close to walls. It is found that the near-wall correction is necessary not only for the conducting wall but also for the adiabatic wall. For an infinitely long 5-μm diameter hot wire, measurement error begins to appear at Y+ < 5 for an infinitely conducting wall and at Y+ < 2 for an adiabatic wall. In addition to the distance from wall, the wire diameter also exerts significant influence on the velocity measurements. However, provided the flow is two-dimensional (2-D), the effect of operating overheat ratio seems to be insignificant. 相似文献
117.
Quantum key generated by using a fiber optic Mach Zehnder interferometer incorporating a fiber optic ring resonator is proposed. The generated quantum key is distributed via an optical wireless link system, which is available for the free space link. The random quantum bits can be formed and used as the secret codes in quantum communication system. By adding an ancillary photon after the signal photon within the correlation time of the fiber noise and by performing quantum parity checking, the high fidelity to the noiseless quantum in free space is achieved by the technique known as the quantum error correction. 相似文献
118.
119.
The problem of calculating the equilibrium properties ofv-dimensional fluid mixture of hardv-spheres is studied. High temperature expansion for the density independent radial distribution function is derived for a
hardv-sphere mixture. The ‘excess’ quantum corrections to the second virial coefficient and the excess free energy are also studied.
Significant features are the large increase in ‘excess’ quantum correction with increasing dimensionality. 相似文献
120.
In this work, we study the localization of the vector gauge field in two five-dimensional braneworlds generated by scalar fields coupled to gravity. The sine–Gordon like potentials are employed to produce different thick brane setups. A zero mode localized is obtained, and we show the existence of reverberations with the wave solutions indicating a quasi-localized massive mode. More interesting results are achieved when we propose a double sine–Gordon potential to the scalar field. The resulting thick brane shows a more detailed topology with the presence of an internal structure composed by two kinks. The massive spectrum of the gauge field is revalued on this scenario revealing the existence of various resonant modes. Furthermore, we compute the corrections to Coulomb law coming from these massive KK vector modes in these thick scenarios, which is concluded that the dilaton parameter regulates these corrections. 相似文献