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Proton microprobe analysis of zinc in skeletal tissues. [Proton induced x-ray emission analysis]

Description: A proton microprobe with windowless exit port was used to study zinc distributions in various types of skeletal tissues. The use of an external beam facilitated positioning of the targets for examination of particular points of interest. The proton microprobe is uniquely suited to this work since it combines high sensitivity for zinc determinations in thick samples with good spatial resolution. Measurements on rat and rabbit Achilles tendon showed a significant increase in zinc concentrations a… more
Date: June 1, 1980
Creator: Doty, S. B.; Jones, K. W.; Kraner, H. W.; Shroy, R. E. & Hanson, A. L.
Partner: UNT Libraries Government Documents Department
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Determination of surface oxide compositions on Alloy 600 using Rutherford backscattering

Description: The surface composition of oxides formed on Alloy 600 under conditions similar to those in the primary side of PWR heat exchangers has been studied as a function of potential using Rutherford backscattering and proton inelastic scattering. Electropolished samples of Alloy 600 were exposed at several potentials to a solution of 0.18M H/sub 3/BO/sub 3/(2000 ppM B) with 0.28M LiOH (1.4 ppM Li) at 300/sup 0/C for 450 hours. The potentials relative to an internal hydrogen electrode ranged from -.09 … more
Date: January 1, 1984
Creator: Hanson, A. L.; Isaacs, H. S. & Kraner, H. W.
Partner: UNT Libraries Government Documents Department
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Concentration profile of hydrogen near the surface of niobium

Description: Samples hydrided in two different ways were investigated. The materials used were thin foils (50 ..mu..m, MARZ grade) of niobium, 10 x 25 mm in size. The two methods of hydriding produced different surface conditions which were the subject of the present investigation. One method consisted of the following procedures. The samples were outgassed and cleaned in UHV to remove virtually all the interstitial impurities from the bulk and surface. A small spot of Pd was then deposited onto the clean s… more
Date: January 1, 1982
Creator: Pick, M. A.; Hanson, A.; Jones, K. W. & Goland, A. N.
Partner: UNT Libraries Government Documents Department
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Application of Synchrotron Radiation to X-Ray Fluorescence Analysis of Trace Elements

Description: The development of synchrotron radiation x-ray sources has provided the means to greatly extend the capabilities of x-ray fluorescence analysis for determinations of trace element concentrations. A brief description of synchrotron radiation properties provides a background for a discussion of the improved detection limits compared to existing x-ray fluorescence techniques. Calculated detection limits for x-ray microprobes with micrometer spatial resolutions are described and compared with exper… more
Date: August 1, 1986
Creator: Gordon, B. M.; Jones, K. W. & Hanson, A. L.
Partner: UNT Libraries Government Documents Department
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The role of high-energy synchrotron radiation in biomedical trace element research

Description: This paper will present the results of an investigation of the distribution of essential elements in the normal hepatic lobule. the liver is the organ responsible for metabolism and storage of most trace elements. Although parenchymal hepatocytes are rather uniform histologically, morphometry, histochemistry, immunohistochemistry, and microdissection with microchemical investigations have revealed marked heterogeneity on a functional and biochemical level. Hepatocytes from the periportal and pe… more
Date: January 1, 1987
Creator: Pounds, J. G.; Long, G. J.; Kwiatek, W. M.; Jones, K. W.; Gordon, B. M. & Hanson, A. L.
Partner: UNT Libraries Government Documents Department
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Trace element distribution in the rat cerebellum

Description: Spatial distributions and concentrations of trace elements (TE) in the brain are important because TE perform catalytic structural functions in enzymes which regulate brain function and development. We have investigated the distributions of TE in rat cerebellum. Structures were sectioned and analyzed by the Synchrotron Radiation Induced X-ray Emission (SRIXE) method using the NSLS X-26 white-light microprobe facility. Advantages important for TE analysis of biological specimens with x-ray micro… more
Date: October 1, 1989
Creator: Kwiatek, W. M.; Long, G. J.; Pounds, J. G.; Reuhl, K. R.; Hanson, A. L. & Jones, K. W.
Partner: UNT Libraries Government Documents Department
open access

Determination of the Occurrence of Gold in an Unoxidized Carlin-Type Ore Sample Using Synchrotron Radiation

Description: The occurrence of the so-called invisible gold in two unoxidized Carlin-type gold samples from Nevada have been determined using synchrotron x-ray fluorescence (SXRF) analysis at the National Sychrotron Light Source, Brookhaven National Laboratory. The samples were a bedded sample from the east ore zone of the Carlin deposit and a breccia sample from Horse Canyon. Preliminary results show that gold is found only in the Horse Canyon breccia sample. Experimental details including other x-ray line… more
Date: January 1, 1986
Creator: Chen, J. R.; Chao, E. C. T.; Minkin, J. A.; Back, J. M.; Bagby, W. C.; Rivers, M. L. et al.
Partner: UNT Libraries Government Documents Department
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An X-Ray Microprobe Beam Line for Trace Element Analysis

Description: The application of synchrotron radiation to an x-ray microprobe for trace element analysis is a complementary and natural extension of existing microprobe techniques using electrons, protons, and heavier ions as excitation sources for x-ray fluorescence. The ability to focus charged particles leads to electron microprobes with spatial resolutions in the sub-micrometer range and down to 100 ppM detection limits and proton microprobes with micrometer resolution and ppM detection limits. The chara… more
Date: January 1, 1987
Creator: Gordon, B. M.; Hanson, A. L.; Jones, K. W.; Kwiatek, W. M.; Long, G. J.; Pounds, J. G. et al.
Partner: UNT Libraries Government Documents Department
open access

Some uncertainties associated with preparation of standards in organic matrix

Description: Until recently no techniques which have multielement detection capability, high sensitivity and good spatial resolution in relatively thick tissue sections have existed. The use of proton induced x-ray emission /PIXE/ and synchrotron radiation induced x-ray emission /SRIXE/ using proton and x-ray microbeams changed this situation. However there are some difficulties with the existing standards for quantitatively calibrating the trace elements concentration in biological materials. For the purpo… more
Date: January 1, 1986
Creator: Cholewa, M.; Hanson, A. L.; Jones, K. W.; McNally, W. P. & Fand, I.
Partner: UNT Libraries Government Documents Department
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Mapping of trace elements with photon microprobes: x-ray fluorescence with focussed synchrotron radiation

Description: High energy electron synchrotron storage rings provide copious quantities of polarized photons that make possible the mapping of many trace elements with sensitivities at the parts per billion (ppB) level with spatial resolutions in the micrometer range. The brightness of the x-ray ring of the National Synchrotron Light Source (NSLS), presently being commissioned, will be five orders of magnitude larger than that of the bremsstrahlung spectrum of state-of-the-art rotating anode tubes. We will d… more
Date: April 1, 1985
Creator: Hanson, A. L.; Jones, K. W.; Gordon, B. M.; Pounds, J. G.; Rivers, M. L. & Schidlovsky, G.
Partner: UNT Libraries Government Documents Department
open access

Micropixe as a tool to search for uranium-bearing particles in lung tissues

Description: A proton microbeam is proposed as a tool to search for uranium-bearing particles in lung tissues. Preliminary experiments have been undertaken by irradiating with protons lung tissues of dogs previously exposed to uranium ore. 7 references.
Date: January 1, 1982
Creator: Paschoa, A. S.; Wrenn, S. C.; Miller, M. E.; Jones, K. W.; Cholewa, M. & Hanson, A. L.
Partner: UNT Libraries Government Documents Department
open access

X-ray microscopy using synchrotron radiation

Description: The system for x-ray microscopy now being developed at the X-26 beam line of the Brookhaven National Synchrotron Light Source (NSLS) is described here. Examples of the use of x-ray microscopy for trace element geochemistry, biology and medicine, and materials investigations are given to emphasize the scientific applications of the technique. Future directions for the improvement and further development of the X-26 microscope and of the x-ray microscopy field in general are discussed. 11 refs., … more
Date: January 1, 1989
Creator: Jones, K. W.; Gordon, B. M.; Hanson, A. L.; Pounds, J. G.; Rivers, M. L.; Schidlovsky, G. et al.
Partner: UNT Libraries Government Documents Department
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Synchrotron x-ray fluorescence and extended x-ray absorption fine structure analysis

Description: The advent of dedicated synchrotron radiation sources has led to a significant increase in activity in many areas of science dealing with the interaction of x-rays with matter. Synchrotron radiation provides intense, linearly polarized, naturally collimated, continuously tunable photon beams, which are used to determine not only the elemental composition of a complex, polyatomic, dilute material but also the chemical form of the elements with improved accuracy. Examples of the application of sy… more
Date: January 1, 1984
Creator: Chen, J. R.; Gordon, B. M.; Hanson, A. L.; Jones, K. W.; Kraner, H. W.; Chao, E. C. T. et al.
Partner: UNT Libraries Government Documents Department
open access

Utilization of synchrotron radiation for trace-element analyses in toxicology of metals

Description: The use of SXRF will nicely complement other more widely used analytical techniques for trace elements. The experiments at CHESS showed minimum detectable limits for 1-mm thick organic matrices with monochromated photon beams to be on the order of 160 to 300 ppB for Ni to Sr with minimal structural damage to the material being irradiated. Extrapolations to operating conditions at the NSLS, with a facility designed for XRF, indicate the MDL limits of 10 to 100 ppB should be achievable. The utili… more
Date: January 1, 1983
Creator: Hanson, A. L.; Jones, K. W.; Kraner, H. W.; Gordon, B. M. & Chen, J. R.
Partner: UNT Libraries Government Documents Department
open access

Application of synchrotron radiation to elemental analysis

Description: The use of a synchrotron storage ring as a high brightness source for production of monoergic, variable energy, and highly polarized x-ray beams promises to revolutionize the field of elemental analysis. The results of exploratory work using the Cornell synchrotron facility, CHESS, will be described. Design considerations and features of the new X-Ray Microprobe Facility now under construction at the Brookhaven National Synchrotron Light Source will be presented. This facility will be used for … more
Date: January 1, 1983
Creator: Jones, K. W.; Gordon, B. M.; Hanson, A. L.; Hastings, J. B.; Howells, M. R.; Kraner, H. W. et al.
Partner: UNT Libraries Government Documents Department
open access

Development of an X-Ray Fluorescence Microprobe at the National Synchrotron Light Source, Brookhaven National Laboratory: Early Results: Comparison With Data From Other Techniques

Description: Theoretical predictions for the detection levels in x-ray fluorescence analysis with a synchrotron storage ring are being achieved experimentally at several laboratories. This paper is deliberately restricted to the state of development of the Brookhaven National Laboratory/University of Chicago instruments. Analyses at the parts per million (ppM) level are being made using white light apertured to 20 ..mu..m and an energy dispersive system. This system is particularly useful for elements with … more
Date: January 1, 1986
Creator: Smith, J. V.; Rivers, M. L.; Sutton, S. R.; Jones, K. W.; Hanson, A. L. & Gordon, B. M.
Partner: UNT Libraries Government Documents Department
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Characterization of Alloy 600 surfaces after exposure to a caustic environment

Description: The surface morphology and compositions of as-received and electropolished Alloy 600 surfaces have been studied using scanning electron microscopy and /sup 4/He/sup +/ Rutherford Backscattering. The samples were exposed to 1% NaOH with 1% Na/sub 2/CO/sub 3/ solutions over a range of potentials. The as-received surfaces did not show any distinctive changes whereas the electropolished surfaces were markedly dependent on the underlying metal. Between -90 and 70 mV, relative to a nickel/hydrogen el… more
Date: January 1, 1983
Creator: Isaacs, H. S.; Kraner, H. W. & Hanson, A. L.
Partner: UNT Libraries Government Documents Department
open access

X-ray microscopy using collimated and focussed synchrotron radiation

Description: X-ray microscopy is a field that has developed rapidly in recent years. Two different approaches have been used. Zone plates have been employed to produce focused beams with sizes as low as 0.07 ..mu..m for x-ray energies below 1 keV. Images of biological materials and elemental maps for major and minor low Z have been produced using above and below absorption edge differences. At higher energies collimators and focusing mirrors have been used to make small diameter beams for excitation of char… more
Date: January 1, 1987
Creator: Jones, K. W.; Kwiatek, W. M.; Gordon, B. M.; Hanson, A. L.; Pounds, J. G.; Rivers, M. L. et al.
Partner: UNT Libraries Government Documents Department
open access

The Application of a Synchrotron Radiation Microprobe to Trace Element Analysis

Description: Synchrotron radiation is light emitted by electrons when accelerated in a circular orbit. Properties of synchrotron radiation important to trace element analysis by x-ray fluorescence analysis include a broad, continuous and tunable energy spectrum for K- and L-shell excitation of all elements; a linearly polarized source reducing the scattered radiation backgrounds; low energy deposition in the target; and an appreciable flux in narrow energy bandwidths for chemical speciation. Experiments to … more
Date: January 1, 1987
Creator: Gordon, B. M.; Hanson, A. L.; Jones, K. W.; Kwiatek, W. M.; Long, G. J.; Pounds, J. G. et al.
Partner: UNT Libraries Government Documents Department
open access

X-ray fluorescence with synchrotron radiation

Description: X-ray fluorescence (XRF) has long been used to make measurements of trace element concentrations in biological materials with very high sensitivity. It has not been previously possible to work with micrometer spatial resolutions because of the relatively low brightness of x-ray tubes. This situation is much improved by using synchrotron storage ring x-ray sources since the brightness of the synchrotron source is many orders of magnitude higher than is obtained with the most intense tube sources… more
Date: March 1, 1986
Creator: Jones, K. W.; Gordon, B. M.; Hanson, A. L.; Pounds, J. G. & Schidlovsky, G.
Partner: UNT Libraries Government Documents Department
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Charge collection in silicon strip detectors

Description: The use of position sensitive silicon detectors as very high resolution tracking devices in high energy physics experiments has been a subject of intense development over the past few years. Typical applications call for the detection of minimum ionizing particles with position measurement accuracy of 10 ..mu..m in each detector plane. The most straightforward detector geometry is that in which one of the collecting electrodes is subdivided into closely spaced strips, giving a high degree of se… more
Date: November 1, 1982
Creator: Kraner, H. W.; Beuttenmuller, R.; Ludlam, T.; Hanson, A. L.; Jones, K. W.; Radeka, V. et al.
Partner: UNT Libraries Government Documents Department
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Trace element measurements with synchrotron radiation

Description: Aspects of the application of synchrotron radiation to trace element determinations by x-ray fluorescence have been investigated using beams from the Cornell facility, CHESS. Fluoresced x rays were detected with a Si(Li) detector placed 4 cm from the target at 90/sup 0/ to the beam. Thick samples of NBS Standard Reference Materials were used to calibrate trace element sensitivity and estimate minimum detectable limits for this method.
Date: January 1, 1982
Creator: Hanson, A. L.; Kraner, H. W.; Jones, K. W.; Gordon, B. M. & Mills, R. E.
Partner: UNT Libraries Government Documents Department
open access

U-bearing particles in miners' and millers' lungs

Description: The size distribution of uranium-bearing particles in air particulates in occupational areas of active uranium mines and mills is largely uninvestigated. Investigation of the size of residual uranium-bearing particles in uranium miners' and millers' lungs is warranted because significant inhalation of uranium can occur in certain occupational areas. Average uranium concentrations of about 0.3 ppM U in uranium miners' and millers' lungs have been reported. Local uranium concentrations in uranium… more
Date: January 1, 1984
Creator: Paschoa, A. S.; Wrenn, M. E.; Singh, N. P.; Miller, S. C.; Jones, K. W.; Cholewa, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Risk comparisons based on representative source terms with the NUREG-1150 results

Description: Standardized source terms, based on a specified release of fission products during potential accidents at commercial light water nuclear reactors, have been used for a long time for regulatory purposes. The siting of nuclear power plants, for example, which is governed by Part 100 of the Code of Federal Regulations Title 10, has utilized the source term recommended in TID-14844 supplemented by Regulatory Guides 1.3 and 1.4 and the Standard Review Plan. With the introduction of probabilistic ris… more
Date: December 1, 1993
Creator: Mubayi, V.; Davis, R. E. & Hanson, A. L.
Partner: UNT Libraries Government Documents Department
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