Search Results

You are looking at 1 - 5 of 5 items for

  • Author or Editor: C. Campbell x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

The validity of the Roy approximation for citation counting is critically evaluated.

Restricted access

Abstract  

Three proposed National Bureau of Standards clay standard reference materials, flint clay SRM 97b, plastic clay, SRM 98b, and brick, SRM 679 were investigated for homogeneity with respect to their contents of Sm, La, Sc, Th, Hf, As, Ga, Fe and Cr. Sub-samples were analyzed by instrumental neutron activation analysis (INAA) and replicate determinations were made on nominal sample weights of 100, 400, 750, and 1000 g. For Sm, La, Sc and Th, no increase in the relative standard deviation with decreasing sample weight was observed in all SRMs indicating that subsampling error for these elements was not a large component of the overall error. For Ga in all SRMs and Cr, As and Fe in SRM 98b, an increase in the relative standard deviation with decreasing sample weight suggests that these elements are concentrated in a minor component of the sample. The three clays should be good reference materials for trace element microanalysis for the elements investigated.

Restricted access
Acta Mathematica Hungarica
Authors: C. Campbell, E. Robertson, M. Ruškuc, and R. Thomas
Restricted access

Abstract  

Matrix-assisted laser desorption/ionization coupled with time-of-flight mass spectrometry (MALDI/TOF-MS) was used for the analysis of low-molecular phosphate compounds found in Hanford tank wastes. The mass spectra of these compounds indicate protonated peaks as well as sodium adducts. Analytical methods presently utilized for the analysis of the phosphate-related organics are both time consuming and labor intensive. A promising alternative is MALDI/TOFMS. The MALDI process produces both positive and negative ions directly and very little sample is required. In addition, there is limited sample preparation and minimal hazardous waste production.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors: G. Milburn, C. Campbell, A. Shand, A. Werninck, J. Varga, K. Belina, and G. Baksay
Restricted access