Mg vii and Si ix line ratios in the sun     

F. P. Keenan  A. E. Kingston  K. M. Aggarwal  K. G. Widing 《Solar physics》1986,103(2):225-230

Recent R-matrix calculations of electron excitation rates for Mg vii and Si ix are used to determine the theoretical density sensitive emission line ratios R ₁= I(2s2p ^{3 1} D ⁰ - 2s ² 2p ^{2 1} D ^e )/I(2s2p ^{3 3} S ⁰ - 2s ² 2p ^{2 3} P ₂ ^e ) and R ₂= I(2s2p ^{3 1} P ⁰ - 2s ² 2p ^{2 1} D ^e )/I(2s2p ^{3 3} S ⁰ - 2s ² 2p ^{2 3} P ₂ ^e ). These are found to be quite similar to the earlier results of Mason and Bhatia. Electron densities derived using observed R ₁ and R ₂ ratios from Skylab NRL XUV spectra of solar flares and active regions are in good agreement, and compare favourably with those deduced from ions formed at similar electron temperatures to Mg vii and Si ix.  相似文献   

Theoretical emission line ratios for O vii in low-density plasmas     

F. P. Keenan  S. S. Tayal  A. E. Kingston 《Solar physics》1984,92(1-2):75-79

New electron excitation rates for O vii calculated by Tayal and Kingston using the R-matrix method are used to determine theoretical emission line strengths. Values of the electron density sensitive ratio R (forbidden line to intercombination line) are found to be very similar to those deduced by other authors. However the temperature sensitive ratios G (intercombination plus forbidden lines to resonance line) are approximately 20% lower than the best previous estimates. The observed value of G for solar active regions (G = 1.0 ± 0.1) predicts an electron temperature in the range 1.1 × 10⁶ K < T _e < 1.8 × 10⁶ K, which overlaps that of maximum O vii emissivity, T _M = 1.8 × 10⁶ K. In addition, the theoretical G versus T _e curve is in excellent agreement with that observed for a Tokamak plasma.  相似文献   

The benthic infauna of the North Sea: species distribution and assemblages   总被引：7，自引：2，他引：7  

Kunitzer  A.; Basford  D.; Craeymeersch  J. A.; Dewarumez  J. M.; Dorjes  J.; Duineveld  G. C. A.; Eleftheriou  A.; Heip  C.; Herman  P.; Kingston  P.; Niermann  U.; Rachor  E.; Rumohr  H.; de Wilde  P. A. J. 《ICES Journal of Marine Science》1992,49(2):127-143

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Oil contamination of sedimentary shores of the Galápagos Islands following the wreck of the Jessica     

Kingston PF  Runciman D  McDougall J 《Marine pollution bulletin》2003,47(7-8):303-312

Sediment samples were collected from sandy beaches at a variety of sites in the southern Galápagos Archipelago to assess levels of hydrocarbon contamination following the wreck of the oil tanker Jessica. Hydrocarbon levels in sediments were generally very low by international standards ranging between 0.4 and 48.9 ppm, with contamination attributable to the Jessica only detected at three sites Santa Fe, Playa Estación (Puerto Ayora, Santa Cruz) and Long Beach (Isabela). There was evidence of residual hydrocarbon contamination from sources other than the wreck of the Jessica.  相似文献   

Reactions under plasma conditions: M. Venugoplan (Editor): Volumes I. Wiley-Interscience, 1971. Volume I,xi + 599 pp. £ 14.00     

A.E. Kingston 《Planetary and Space Science》1972

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Si III electron temperature diagnostics for the solar transition region     

F. P. Keenan  P. L. Dufton  A. E. Kingston 《Solar physics》1989,123(1):33-39

R-matrix calculations of electron impact excitation rates for transitions in Si iii are used to derive the electron-density-sensitive emission line ratios R ₁ = I(1113.2 Å)/I(1206.3 Å), R ₂ = I(1298.9 Å)/I(1206.3 Å), and R ₃ = I(1296.7 Å)/I(1206.3 Å). A comparison of these with observational data for several solar features obtained with the Harvard S-055 spectrometer on board Skylab reveals that theory and experiment are compatible if the electron temperature of the Si iii emitting region of the solar atmosphere is log T _e = 4.5, but not if log T _e = 4.7. The implication of the choice of a lower temperature on the electron energy distribution function is also briefly discussed.  相似文献   

Theoretical Neix line ratios compared to solar observations     

F. P. Keenan  S. S. Tayal  A. E. Kingston 《Solar physics》1984,94(1):85-89

R-matrix calculations of the 1¹S - 2³S and 1¹S - 2³P electron excitation rates in He - like Cv, Ovii, and Mgxi by Kingston and Tayal are used to interpolate results for Neix. Adoption of these in emission line strength calculations leads to values for the density-sensitiveR ratio very similar to those of Pradhanet al. and Wolfsonet al., although the temperature-sensitiveG ratios are approximately 10 to 20 % lower than those deduced by these authors. However the present theoretical value ofG at the temperature of maximum Neix emission,G(T _m) = 0.82, is in excellent agreement with those observed by the SMM and P78-1 satellites for the 1980, November5 flare (G = 0.83 ± 0.01) and nonflaring active regions (G = 0.80 ± 0.05), respectively.  相似文献   

白云鄂博地区碳酸岩墙及岩墙旁侧石英岩中的包裹体研究   总被引：11，自引：6，他引：11  

倪培  A H RANKIN  周进 《岩石学报》2003,19(2):297-306

白云鄂博的碳酸岩墙中包裹体类型有多子晶包裹体、两相水溶液包裹体、含CO_2三相包裹体和含子晶三相包裹体,岩相学和显微测温结果表明,这些包裹体与国外典型的碳酸岩中的包裹体具有很大程度的一致性,反映了其岩浆成因特点;碳酸岩墙中旁侧的白云鄂博H2石英岩中含有大量的流体包裹体,主要类型为NaCl-H_2O包裹体、CO_2包裹体和H_2O±CO_2±固体的包裹体。包裹体的岩相学、显微测温、阴极发光特征、包裹体成分ICP-MS测定,激光拉曼研究等,揭示出石英岩中的包裹体捕获了来自碳酸岩墙的碳酸岩浆流体,提供了一种不可多得的直接研究碳酸岩流体的手段。  相似文献   

A new geodemographic classification of commuting flows for England and Wales     

Stephen Hincks  Richard Kingston  Brian Webb  Cecilia Wong 《International journal of geographical information science》2018,32(4):663-684

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Climate change uncertainty in environmental flows for the Mekong River     

J.R. Thompson  C.L.R. Laizé  A.J. Green  M.C. Acreman  D.G. Kingston 《水文科学杂志》2014,59(3-4):935-954

Abstract

A MIKE SHE model of the Mekong, calibrated and validated for 12 gauging stations, is used to simulate climate change scenarios associated with a 2°C increase in global mean temperature projected by seven general circulation models (GCMs). Impacts of each scenario on the river ecosystem and, hence, uncertainty associated with different GCMs are assessed through an environmental flow method based on the range of variability approach. Ecologically relevant hydrological indicators are evaluated for the baseline and each scenario. Baseline-to-scenario change is assessed against thresholds that define likely risk of ecological impact. They are aggregated into single scores for high and low flows. The results demonstrate considerable inter-GCM differences in risk of change. Uncertainty is larger for low flows, with some GCMs projecting high and medium risk at the majority of locations, and others suggesting widespread no or low risk. Inter-GCM differences occur along the main Mekong, as well as within major tributaries.