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X-ray fluorescence analysis study. Final report, December 1, 1970-December 31, 1977

Description: This report has described the most significant experiments and the results obtained, during the development of a system for the detection and measurement of Pb in blood using radioisotope-excited x-ray fluorescence analysis, over the contract period. Briefly, the report described: detector selection; source selection; source-sample-detector geometry; sample preparation; system calibration; and separation technique. (PSB)
Date: January 1, 1978
Creator: Kneip, T J & Laurer, G R
Item Type: Refine your search to only Report
open access

X-ray fluorescence cross sections for K and L x rays of the elements

Description: X-ray fluorescence cross sections are calculated for the major x rays of the K series 5 less than or equal to Z less than or equal to 101, and the three L series 12 less than or equal to Z less than or equal to 101 in the energy range 1 to 200 keV. This calculation uses Scofield's theoretical partical photoionization cross sections, Krause's evaluation of fluorescence and Coster-Kronig yields, and Scofield's theoretical radiative rates. Values are presented in table and graph format, and an est… more
Date: June 1, 1978
Creator: Krause, M. O.; Nestor, C. W. Jr.; Sparks, C. J. Jr. & Ricci, E.
Item Type: Refine your search to only Report
open access

X-ray fluorescence with synchrotron radiation

Description: An experimental set-up for x-ray fluorescence analysis with synchrotron radiation was built and installed at the Stanford Synchrotron Radiation Project. X-ray spectra were taken from numerous and varied samples in order to assess the potential of synchrotron radiation as an excitation source for multielement x-ray fluorescence analysis. For many applications, the synchrotron radiation technique is shown to be superior to other x-ray fluorescence methods, especially those employing electrons and… more
Date: January 1, 1978
Creator: Raman, S. & Sparks, C.J. Jr.
Item Type: Refine your search to only Article
open access

X-ray measurements of stresses and defects in EFG and large grained polycrystalline silicon ribbons. First quarterly report

Description: The first model of a modified Bond goniometer has been built and tested for the precision measurement of interplanar spacings in Si-single crystals. A change in interplanar spacing ..delta..d/d approximately = to +- 10/sup -5/ can be detected which corresponds to surface stresses of the order of +- 1000 psi. A second version of the goniometer is being assembled incorporating a removable microscope for precision alignment of the Si-strip into the primary X-ray beam.
Date: January 1, 1978
Creator: Wagner, C.N.J.
Item Type: Refine your search to only Report
open access

X-ray microanalysis using an HVEM

Description: The interfacing of an energy dispersive x-ray spectrometer (EDS) to an HVEM has been suggested during the last few years as a means by which the mass sensitivity of x-ray analysis in a TEM can be increased. The prediction of higher sensitivity is related to the anisotropic distribution of continuum radiation generated by high energy electron excitation of a thin sample. Depending on the geometry, this can result in an increase in the measured peak-to-background (P/B) ratio of a characteristic l… more
Date: January 1, 1978
Creator: Zaluzec, N.J.; Kenik, E.A. & Bentley, J.
Item Type: Refine your search to only Article
open access

X-ray pole figure analysis. Final report

Description: Crystal orientation in a polycrystalline material determines the characteristics of the material. When a material is deformed, a specific crystallographic orientation of the grains with respect to the deformation direction becomes predominant. A technique used to determine crystal orientation or texture is the construction of a pole figure. A pole figure is a contour map, in stereographic projection, of the concentration of poles of selected crystallographic planes as a function of spatial orie… more
Date: September 1, 1978
Creator: Jarboe, D.M. & Lacey, D.E.
Item Type: Refine your search to only Report
open access

X-ray powder diffraction of einsteinium compounds

Description: X-ray powder diffraction (XRPD) analysis has proven to be extremely valuable in the study of the transplutonium elements. The high specific activity and the thermal energy associated with the radioactive decay of einsteinium isotopes make XRPD analysis of einsteinium samples very difficult. The major problems are destruction of the samples crystallinity and alteration of their chemical composition. Blackening of the X-ray film also compromises the analyses. By applying certain guidelines given … more
Date: January 1, 1978
Creator: Haire, R.G. & Peterson, J.R.
Item Type: Refine your search to only Article
open access

X-ray spectrometric determination of glass content of melts incorporating radioactive waste: a feasibility study

Description: X-ray fluorescence spectrometry was evaluated for the determination of glass content and homogeneity of glass incorporating high-level radioactive waste. Accuracy and precision were determined for analyses of Al/sub 2/O/sub 3/, SiO/sub 2/, CaO, TiO/sub 2/, MnO, Fe/sub 2/O/sub 3/, and NiO in specimens of known composition. These specimens were prepared by fusing powdered glass with nonradioactive synthetic waste. Matrix effects of sodium on these analyses were specifically evaluated. X-ray fluor… more
Date: September 1, 1978
Creator: Slates, R.V.
Item Type: Refine your search to only Report
open access

X-ray transmission/scattering technique for thickness-independent density measurement

Description: A nondestructive technique, using penetrating x radiation, has been developed to measure the density uniformity of low-Z, compressible materials that is independent of material thickness. Thickness independence is achieved by simultaneously monitoring the transmitted and scattered x rays. Results on samples of pressed carbon materials have demonstrated that there is the expected linear relationship between measured quantities and material density, independent of material thickness, and that thi… more
Date: December 20, 1978
Creator: Giacomelli, E. J.
Item Type: Refine your search to only Report
open access

Year-end-report on Heavy-Ion Fusion Program, September 30, 1978

Description: The experimental efforts focused on both the development of a large aperture 2 MeV, 1A Cs/sup +/ ion beams and also a 750 kV, 60 mA Xe/sup +/ ion beams. A conceptual design and cost procedure for heavy-ion induction linacs are considered. Theoretical activities are reported on beam transport, final focusing, parameter studies, and comparison of instability theory with simulation results. (MOW)
Date: September 30, 1978
Item Type: Refine your search to only Report
open access

Zeeman atomic absorption spectrometry

Description: The design and development of a Zeeman atomic absorption spectrometer for trace element analysis are described. An instruction manual is included which details the operation, adjustment, and maintenance. Specifications and circuit diagrams are given. (WHK)
Date: August 1, 1978
Creator: Hadeishi, T. & McLaughlin, R.
Item Type: Refine your search to only Report
open access

Zein synthesis and processing on zein protein body membranes. [Maize proteins]

Description: The storage protein of maize, zein, is translated from messenger RNA on ribosomes bound to the outer membrane of the zein protein bodies. No other proteins appear to be made on this membrane. Before zein is transported through the protein body membrane it undergoes at least two post-translational modifications, which are discussed.
Date: January 1, 1978
Creator: Burr, F A
Item Type: Refine your search to only Article
open access

Zero range three-particle equations. [Karlsson-Zeiger equations]

Description: In order to separate the entire effect of two-particle on-shell scatterings in three-particle systems from the effects of hidden mesonic degrees of freedom (off-shell effects and three-body forces), the zero range limit of the Karlsson-Zeiger equations. Although the Faddeev equations are ambiguous in this limit, the KZ equations remain well defined. Using only two-particle phase shifts, binding energies, and reduced widths, these zero-range equations uniquely predict the three-particle observab… more
Date: April 1, 1978
Creator: Noyes, H. P. & Zeiger, E. M.
Item Type: Refine your search to only Report
open access

ZT-40 administrative plan

Description: An administrative plan for the ZT-40 project has been developed. It describes baselines and procedures that will be used for the remainder of the construction phase of the project.
Date: August 1, 1978
Creator: Thomas, K.S. (comp.)
Item Type: Refine your search to only Report
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