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1.
C. Laughlin 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1988,9(4):273-277
Wavelengths for transitions in the quartet spectrum of C IV are calculated and compared with recent experimental measurements. Transition probabilities and radiative lifetimes are also predicted for several of the lowest 1s 2snl 4 L and 1s2pnl 4 L levels up toL=4. In addition, wavelengths and transition probabilities for some recently observed C IV doublet transitions to then=4 level are presented. 相似文献
2.
3.
Semi-empirical model potential calculations have been performed for bound and continuum properties of Li? and Na?. The calculated electron affinities of the 2s21S state of Li? and the 3s21S and 3p23Pe states of Na? are in agreement with the calculations of Norcross and with experimental data. Positions of possible autoionizing states are calculated using projection and root stabilization methods. The Stieltjes imaging method of Langhoff is employed to compute the photodetachment cross sections of Li? and Na? and the results are in excellent agreement with the close-coupling calculations of Moores and Norcross. A comparison of variational and numerical results for the coupled time-dependent Hartree-Fock photoionization of helium shows that good Stieltjes imaging results can be obtained with a very small basis set for the variational calculation. The continuous photoemission profile for the 3p23Pe state of Na? is also obtained. 相似文献
4.
E. R. Dixon R. J. Laughlin C. J. Watson D. J. Hatch 《Rapid communications in mass spectrometry : RCM》2010,24(5):519-528
Nitrogenous materials can be transferred out of the topsoil, either vertically to a greater depth, or in lateral pathways to surface waters, and they may also become transformed, with the potential of generating environmentally active agents. We measured the production of NO and N2O in two contrasting subsoils (70 to 90 cm): one poorly drained and the other freely drained and compared this with the topsoil (0 to 20 cm) of the corresponding soils. The soils were incubated aerobically in jars with subtreatments of either synthetic cattle urine or deionised water and sampled at intervals up to 34 days. 15N‐NO was used to determine the processes responsible for NO and N2O production. The headspace was analysed for the concentrations of N2O, NO and CO2 and 15N enrichment of N2O. The soil samples were extracted and analysed for NO, NO and NH, and the 15N enrichment of the extracts was measured after conversion into N2O and N2. The study demonstrated the potential for NO, N2O and NO to be generated from subsoils in laboratory incubations. Differences in these N dynamics occurred due to subsoil drainage class. In the freely drained subsoil the rates of NO and NO production were higher than those observed for the corresponding topsoil, with mean maximum production rates of 3.5 µg NO‐N g−1 dry soil on day 16 and 0.12 µg NO‐N g−1 dry soil on day 31. The calculated total losses of N2O‐N as percentages of the applied synthetic urine N were 0.37% (freely drained subsoil), 0.24% (poorly drained subsoil), 0.43% (freely drained topsoil) and 2.09% (poorly drained topsoil). The calculated total losses of NO‐N as percentages of the applied synthetic urine N were 1.53% (freely drained subsoil), 0.02% (poorly drained subsoil), 0.25% (freely drained topsoil) and 0.08% (poorly drained topsoil). Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
5.
James Mc Laughlin 《Central European Journal of Mathematics》2010,8(3):474-487
We derive several new transformations relating WP-Bailey pairs. We also consider the corresponding transformations relating
standard Bailey pairs, and as a consequence, derive some quite general expansions for products of theta functions which can
also be expressed as certain types of Lambert series. 相似文献
6.
This paper describes the accepted meaning of the term ’negative resistance’ and its use in the literature, and discusses the features in the previously published data on QTC TM (market name of a metal-polymer composite) that show that the non-linear, hysteretic current voltage characteristics are not caused by Joule heating. The benefit of the high metal filler loading in QTC TM and other unique features of this composite are reviewed. 相似文献
7.
We explore possible effects of vacuum energy on the evolution of black holes. If the universe contains a cosmological constant, and if black holes can absorb energy from the vacuum, then black hole evaporation could be greatly suppressed. For the magnitude of the cosmological constant suggested by current observations, black holes larger than 4×1024 g would accrete energy rather than evaporate. In this scenario, all stellar and supermassive black holes would grow with time until they reach a maximum mass scale of 6×1055 g, comparable to the mass contained within the present day cosmological horizon. 相似文献
8.
Kong J Yenilmez E Tombler TW Kim W Dai H Laughlin RB Liu L Jayanthi CS Wu SY 《Physical review letters》2001,87(10):106801
The electron transport properties of well-contacted individual single-walled carbon nanotubes are investigated in the ballistic regime. Phase coherent transport and electron interference manifest as conductance fluctuations as a function of Fermi energy. Resonance with standing waves in finite-length tubes and localized states due to imperfections are observed for various Fermi energies. Two units of quantum conductance 2G(0) = 4e(2)/h are measured for the first time, corresponding to the maximum conductance limit for ballistic transport in two channels of a nanotube. 相似文献
9.
Recent experiments suggest that the Ising pyrochlore magnets Ho2Ti2O7 and Dy2Ti2O7 display qualitative properties of the nearest-neighbor "spin ice" model. We discuss the dipolar energy scale present in both these materials and discuss how spin-ice behavior can occur despite the presence of long-range dipolar interactions. We present results of numerical simulations and a mean field analysis of Ising pyrochlore systems. Based on our quantitative theory, we suggest that the spin-ice behavior in these systems is due to long-range dipolar interactions, and that the nearest-neighbor exchange in Dy2Ti2O7 is antiferromagnetic. 相似文献
10.