The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Rick L Paul - One of the best experts on this subject based on the ideXlab platform.
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ngd cold neutron prompt gamma ray Activation Analysis spectrometer at nist
Journal of Radioanalytical and Nuclear Chemistry, 2015Co-Authors: Rick L Paul, Dagistan şahin, J C Cook, Christoph Brocker, Richard M Lindstrom, Donna J OkellyAbstract:A new instrument for cold neutron prompt gamma-ray Activation Analysis is being designed as part of the recent expansion of the cold neutron guide hall at the NIST Center for Neutron Research. This instrument has a 10-fold increase in neutron flux and lower gamma-ray and neutron background compared to the PGAA instrument it will replace at NG7. Monte Carlo based simulation sofware and experimental setups are used in the design phase to mitigate background while preserving high neutron fluence. The new instrument will also provide more space for samples and for experimental setup compared to the old facility.
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elemental characterization of single wall carbon nanotube certified reference material by neutron and prompt γ Activation Analysis
Analytical Chemistry, 2015Co-Authors: J Kucera, Rick L Paul, Marcio Arruda Bacchi, Elisabete A De Nadai Fernandes, John W Bennett, Rabia Oflaz, Marie Kubesova, Attila Stopic, Ralph E Sturgeon, Patricia GrinbergAbstract:Instrumental neutron Activation Analysis with both relative and k0 standardization was used in four experienced laboratories to determine element mass fractions in single-wall carbon nanotube certified reference material (CRM) SWCNT-1. Results obtained were evaluated using the National Institute of Standards and Technology (NIST) “Type B On Bias” approach and yielded consensus values in agreement with National Research Council Canada (NRCC) certified values for Fe, Co, Ni, and Mo and provided mass fraction values for 13 additional elements, namely, Na, Mg, Al, K, Ca, Ti, V, Cr, Mn, Br, La, W, and Au. In addition, prompt γ neutron Activation Analysis was employed to determine mass fractions of H, B, Co, Ni, and Mo. Results of this work provide a basis for the establishment of reference values of element mass fractions in CRM SWCNT-1, thus expanding its usability for more accurate characterization and benchmarking of similar nanotechnology materials.
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cold neutron prompt gamma ray Activation Analysis at nist recent developments
Journal of Radioanalytical and Nuclear Chemistry, 1997Co-Authors: Rick L Paul, Richard M Lindstrom, A E HealdAbstract:The cold neutron capture prompt γ-ray Activation Analysis (CNPGAA) spectrometer located in the Cold Neutron Research Facility (CNRF) at NIST has proven useful for the Analysis of hydrogen and other elements in a wide variety of materials. Modifications of the instrument and the CNRF have resulted in improved measurement capabilities for PGAA. The addition of an atmosphere-controlled sample chamber and Compton suppression have reduced γ-ray background and increased signal-to-noise ratio. More recent revisions are expected to yield still further improvement in analytical capabilities. Replacement of the D2O ice cold source with a liquid H2 moderator is expected to yield a 5–10 fold increase in neutron capture rate, and improved neutron and γ-ray shielding will result in further reduction of the background. Other modifications to the instrument allow easier sample mounting and more precise positioning of samples in the neutron beam. Significant improvements in detection limits and analytical accuracy are expected.
J B Yang - One of the best experts on this subject based on the ideXlab platform.
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prompt gamma neutron Activation Analysis for multi element measurement with series samples
Laser Physics Letters, 2013Co-Authors: J B Yang, Yigang Yang, Xianguo Tuo, Y Cheng, Y F Mou, W Q HuangAbstract:The on-line prompt gamma neutron Activation Analysis (PGNAA) system is used to measure a series of prepared experimental samples to obtain the prompt characteristic γ-rays of the elements Ca, Fe, Si, Al, Mg and S in the examples of SiO2, Al2O3, MgO, CaO (powder), CaO (block), CaCO3, Fe2O3, Fe3O4 and S. The γ-ray energies are: Si, 3.54 or 4.93 MeV; Ca, 4.42 or 6.42 MeV; S, 5.42 MeV; Fe, 5.92 or 7.63 MeV. Meanwhile, the prompt γ-rays of the main elements are measured in an experiment in which SiO2, Al2O3, MgO, CaO (powder), CaO (block), CaCO3, Fe2O3, Fe3O4 and S are blended to constitute a cement sample. The prompt γ-rays of S will contribute more with increase in S mass, as known from the experiment concerning the prompt γ-ray spectrum for different masses of S.
T Springer - One of the best experts on this subject based on the ideXlab platform.
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investigation of the hydrogen uptake of doped srceo3 by tem thermogravimetry and cold neutron prompt gamma Activation Analysis cnpgaa
Solid State Ionics, 1995Co-Authors: F Krug, T Schober, R Paul, T SpringerAbstract:Abstract The microstructure of doped strontium cerate was studied by transmission electron microscopy (TEM). Using thermogravimetry (TG) the temperature dependence of water uptake in atmospheres with different water and oxygen pressures was examined in situ. Absolute hydrogen contents of precharged samples were obtained by cold neutron prompt gamma Activation Analysis (CNPGAA).
Zsolt Révay - One of the best experts on this subject based on the ideXlab platform.
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Prompt gamma neutron Activation Analysis (PGAA): recent developments and applications
Journal of Radioanalytical and Nuclear Chemistry, 2017Co-Authors: Richard M Lindstrom, Zsolt RévayAbstract:Prompt gamma neutron Activation Analysis has become an important part of the analytical toolkit, practiced at several research reactors worldwide. An extensive review of the physics, engineering, and applications of the technique was published in 2004: the present work gives an overview and survey of the literature in the succeeding dozen years.
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determining elemental composition using prompt γ Activation Analysis
Analytical Chemistry, 2009Co-Authors: Zsolt RévayAbstract:Prompt γ-ray spectra sometimes contain hundreds of characteristic peaks, and the masses of the sample components can be determined from dozens of γ-ray peak areas, some of which are affected by spectral interferences. Reliable qualitative and quantitative analyses can only be performed by using a precisely calibrated detector system, an accurate spectroscopic data library, high-quality spectroscopy software, and a sophisticated method to convert raw data into chemical composition. This article describes the steps of the chemical Analysis with prompt γ Activation Analysis (PGAA). A complete data reduction method has been constructed that handles the large number of spectral peaks using statistical procedures, identifies the chemical components based on statistical criteria, and determines the sample composition with a least-squares fit of the masses calculated from the individual peaks. The calculation of the uncertainties as well as the detection and analytical limits are discussed in detail. The validati...
W Q Huang - One of the best experts on this subject based on the ideXlab platform.
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prompt gamma neutron Activation Analysis for multi element measurement with series samples
Laser Physics Letters, 2013Co-Authors: J B Yang, Yigang Yang, Xianguo Tuo, Y Cheng, Y F Mou, W Q HuangAbstract:The on-line prompt gamma neutron Activation Analysis (PGNAA) system is used to measure a series of prepared experimental samples to obtain the prompt characteristic γ-rays of the elements Ca, Fe, Si, Al, Mg and S in the examples of SiO2, Al2O3, MgO, CaO (powder), CaO (block), CaCO3, Fe2O3, Fe3O4 and S. The γ-ray energies are: Si, 3.54 or 4.93 MeV; Ca, 4.42 or 6.42 MeV; S, 5.42 MeV; Fe, 5.92 or 7.63 MeV. Meanwhile, the prompt γ-rays of the main elements are measured in an experiment in which SiO2, Al2O3, MgO, CaO (powder), CaO (block), CaCO3, Fe2O3, Fe3O4 and S are blended to constitute a cement sample. The prompt γ-rays of S will contribute more with increase in S mass, as known from the experiment concerning the prompt γ-ray spectrum for different masses of S.
