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Precise measurements of hyperfine components in the spectrum of molecular iodine

Description: Absolute wave numbers with a typical uncertainty of 1 MHz (95% confidence) were measured for 102 hyperfine-structure components of {sup 127}I{sub 2}. The data cover the range 560-656 nm, with no gaps over 50 cm{sup -1}. The spectra were observed using Doppler-free frequency modulation spectroscopy with tunable cw laser. The laser was locked to selected iodine components and its wave number measured with a high precision Fabry-Perot wavemeter. Accuracy is confirmed by good agreement of 9 of the lines with previous results from other laboratories. These measurements provide a well-distributed set of precise reference lines for this spectral region.
Date: May 1, 1996
Creator: Sansonetti, C.J.
Partner: UNT Libraries Government Documents Department

The spin-dependent neutralino-nucleus form factor for {sup 127}I

Description: We present the results of detailed shell model calculations of the spin-dependent elastic form factor for the nucleus {sup 127}I. the calculations were performed in extremely large model spaces which adequately describe the configuration mixing in this nucleus. Good agreement between the calculated and experimental values of the magnetic moment are found. Other nuclear observables are also compared to experiment. The dependence of the form factor upon the model space and effective interaction is discussed.
Date: December 1, 1996
Creator: Ressell, M.T. & Dean, D.J.
Partner: UNT Libraries Government Documents Department

{sup 129}I interlaboratory comparison

Description: An interlaboratory comparison exercise for {sup 129}I has been organized and conducted. A total of seven laboratories participated in the exercise to either a full or limited extent. In the comparison, a suite of 11 samples were used. This suite of standards contained both synthetic `standard type` materials(i.e., AgI) and environmental materials. The isotopic {sup 129}I/{sup 127}I ratio of the samples varied from 10{sup -8} to 10{sup -14}. Preliminary results of the comparison are presented.
Date: May 1, 1996
Creator: Roberts, M.L.; Caffee, M.W. & Proctor, L.D.
Partner: UNT Libraries Government Documents Department

Neutron capture cross sections for nucleosynthesis

Description: Maxwellian Neutron capture cross sections important for nucleosynthesis processes in stars are computed from the recommended individual resonance parameters, as well as from the measured energy dependent cross sections. The experimental neutron capture cross sections, spanning the energy range from a few keV to about 500 keV are evaluated in the framework of the Lane-Lynn capture formalism by including several partial waves in the analysis. In addition, in a few cases, the neutron inelastic scattering channels are included. The feasibility of extrapolating the calculations to nuclides off the stability line is examined. The effect of stellar temperature in the range from 10 keV to 50 keV on the Maxwellian neutron capture cross sections is investigated. The Maxwellian capture cross sections at 30-KeV for {sup 93}Nb, {sup 127}I, {sup 141}Pr, {sup 150}Sm, {sup 152}Sm, {sup 154}Sm, and {sup 181}Ta are computed and are compared with other determinations.
Date: July 1, 1997
Creator: Mughabghab, S.F.
Partner: UNT Libraries Government Documents Department

Preliminary report on SG126 Task 3: {sup 129}I interlaboratory comparison

Description: An interlaboratory comparison exercise for {sup 129}I has been organized and conducted. A total of seven laboratories participated in the exercise to either a full or limited extent. In the comparison, a suite of 11 samples was used. This suite of standards contained both synthetic `standard type` materials (i.e., AgI) and environmental materials. The isotopic {sup 129}I/{sup 127}I ratio of the samples varied from 10{sup -8} to 10{sup -14}. Results of the comparison are presented.
Date: March 7, 1996
Creator: Roberts, M.L.; Caffee, M.W. & Proctor, I.D.
Partner: UNT Libraries Government Documents Department

Technique development for the extraction of environmental levels of iodide from groundwaters at the Nevada Test Site for the purpose of {sup 129}I/{sup 127}I analyses

Description: A technique was developed to extract iodine from groundwaters with very low concentrations of iodine (on the order of {mu}g/L or ppb). Sufficient iodine was necessary (approximately 5 mg Agl) for analysis of the {sup 129}l/{sup 127}l on the Tandem Accelerator Mass Spectrometer (AMS). The technique for separating iodine from groundwater was developed for the field to eliminate shipping of thousands of liters of water back to the laboratory. The technique was field tested on several springs and wells at the Nevada Test Site (NTS). Preliminary isotope ratios are presented along with total iodine concentrations of the waters. It was also determined that iodine may be used as an early radionuclide migration tool.
Date: February 1, 1994
Creator: Kenneally, J.M.; Harris, L.J. & Nimz, G.J.
Partner: UNT Libraries Government Documents Department

{sup 129}I Interlaboratory comparison: phase I and phase II

Description: An interlaboratory comparison exercise for {sup 129}I was organized and conducted. Nine laboratories participated in the exercise to either a full or limited extent. In Phase I of the comparison, 11 samples were measured. The suite of samples contained both synthetic ''standard type'' materials (i.e., AgI) and environmental materials. The isotopic {sup 129}I/{sup 127}I ratios of the samples varied from 10{sup {minus}8} to 10{sup {minus}14}. In this phase, each laboratory was responsible for its own chemical preparation of the samples. In Phase I, the {sup 129}I AMS measurements for prepared AgI were in good agreement. However, large discrepancies were seen in {sup 129}I AMS measurements of environmental samples. Because of the large discrepancies seen in the Phase I {sup 129}I intercomparison, a subsequent study was conducted. In Phase II of the {sup 129}I intercomparison, three separate laboratories prepared AgI from two environmental samples (IAEA 375 soil and maples leaves). Each laboratory used its own chemical preparation method with each of the methods being distinctly different. The resulting six samples (two sets of three) were then re-distributed to the participating {sup 129}I AMS facilities and {sup 129}I/{sup 127}I ratios measured. Results and discussion of both the Phase I and Phase II interlaboratory comparison are presented.
Date: September 30, 1999
Creator: Caffee, M W & Roberts, M L
Partner: UNT Libraries Government Documents Department

Determination of iodine to compliment mass spectrometric measurements

Description: The dose of iodine-129 to facility personnel and the general public as a result of past, present, and future activities at DOE sites is of continuing interest, WINCO received about 160 samples annually in a variety of natural matrices, including snow, milk, thyroid tissue, and sagebrush, in which iodine-129 is determined in order to evaluate this dose, Currently, total iodine and the isotopic ratio of iodine-127 to iodine-129 are determined by mass spectrometry. These two measurements determine the concentration of iodine-129 in each sample, These measurements require at least 16 h of mass spectrometer operator time for each sample. A variety of methods are available which concentrate and determine small quantities of iodine. Although useful, these approaches would increase both time and cost. The objective of this effort was to determine total iodine by an alternative method in order to decrease the load on mass spectrometry by 25 to 50%. The preparation of each sample for mass spectrometric analysis involves a common step--collection of iodide on an ion exchange bed. This was the focal point of the effort since the results would be applicable to all samples.
Date: November 1, 1994
Creator: Hohorst, F.A.
Partner: UNT Libraries Government Documents Department

Natural iodine and iodine-129 in mammalian thyroids and environmental samples taken from locations in the United States

Description: From symposium on enviromnental surveillance around nuclear installation; Warsaw, Poland (5 Nov 1973). Bovine and other mammalian thyroids, air, precipitation, water, grass, and milk samples from selected locations were analyzed for their natural iodine and iodine-129 content. Particle filters and activated charcoal beds were used to collect the particulate and gaseous iodine fractions from the air. Anion exchange was used for the separation of iodine from liquid samples. Cumbustion methods were used for iodine separation from solid samples, anlon exchange resins, and air filters. Iodine-129 and natural iodine concentrations were determined by neutron activation analysis with a detection limit of about 10/sup 8/ atoms of iodine-129 per sample. Analytical results of both /sup 129/I concentrations and ratios of atoms of /sup 129/I per atom of /sup 127/I for these samples are summarized. The small radiation doses to human thyroids projected from these low /sup 129/I concentrations are also discussed. (auth)
Date: January 1, 1973
Creator: Brauer, F.P.; Soldat, J.K.; Tenny, H. & Strebin, R.S. Jr.
Partner: UNT Libraries Government Documents Department

129I interlaboratory comparison: phase I and phase II results

Description: An interlaboratory comparison exercise for 129I was organized and conducted. A total of nine laboratories participated in the exercise to either a full or limited extent. In Phase I of the comparison, a suite of 11 samples were measured. The suite of samples contained both synthetic `standard type` materials (i.e., AgI) and environmental materials. The isotopic 129I/127I ratios of the samples varied from 10`-8 to 10`-14. In this phase, each laboratory was responsible for its own chemical preparation of the environmental samples. The 129I AMS measurements obtained at different laboratories for prepared AgI were in good agreement. However, large discrepancies were seen in 129I AMS measurements of environmental samples. Because of the large discrepancies seen in the Phase I intercomparison, a subsequent study was conducted. In Phase II of the comparison, AgI was prepared from two environmental samples (IAEA 375 soil and maples leaves) by three separate laboratories. Each laboratory used its own chemical preparation method with each of the methods being distinctly different. The resulting six samples (two sets of three) were then redistributed to the participating 129I AMS facilities and 129I/127I ratios measured. Results and discussion of both the Phase I and Phase II interlaboratory comparison are presented.
Date: July 1, 1997
Creator: Roberts, M.I.; Caffee, M.W. & Proctor, I.D.
Partner: UNT Libraries Government Documents Department

Cross sections for (p,n) and (d,2n) reactions on /sup 79/Br and /sup 127/I: An evaluation of literature and model calculated results

Description: We have evaluated (p,n) and (d,2n) cross sections on /sup 79/Br and /sup 127/I, and made these cross sections available for test diagnostics. We believe that these interim cross sections are of reasonable accuracy and should be used for diagnostic interpretations until more precise measurements can be made. Our evaluation consisted of a literature search and an examination of the available experimental data. These data were supplemented by statistical model calculations using both the STAPRE and ALICE codes. We found reasonably good measured data (from threshold to the peak of the excitation function) for the (p,n) reaction on both /sup 79/Br and /sup 127/I. The literature data for the (d,2n) reaction on /sup 127/I are questionable and no data were found for the (d,2n) reaction on /sup 79/Br. We have, therefore, relied completely on calculations for the (d,2n) cross sections for both /sup 79/Br and /sup 127/I. 4 figs., 5 tabs.
Date: February 1, 1989
Creator: Lanier, R.G.; Mustafa, M.G. & West, H.I. Jr.
Partner: UNT Libraries Government Documents Department

/sup 127/I Moessbauer study of Chevrel-phase superconductors Mo/sub 6/X/sub 6/I/sub 2/ (X = S,Te)

Description: The Chevrel-phase compounds Mo/sub 6/X/sub 6/I/sub 2/ (X = S,Te) exhibit very interesting superconducting behvior. The transition temperatures dramatically increase in both Mo/sub 6/X/sub 8/ structures be replacing 2 of the X atoms with iodine atoms. This enhancement in superconducting behavior is closely related to the number of electrons on the Mo/sub 6/ cluster in these compounds. The iodine atoms in these compounds preferentially occupy the 2c sites while the remaining X atoms occupy the 6f sites. We have performed the Moessbauer effect measurements using the 57.6-keV transition in /sup 127/I to evaluate the charge on the iodine. Assuming the charge on S to be -2, the experimental value of nearly -1 charge on iodine leaves 22.3 electrons per Mo/sub 6/ cluster which is close to that predicted in SnMo/sub 6/S/sub 8/). In Mo/sub 6/Te/sub 6/I/sub 2/, assuming Te to have nearly -1 charge, we obtain 28.3 electrons per Mo/sub 6/ cluster. The observation of superconductivity in this compound then reflects a significantly distinct band structure of tellurides compared to those of sulphides. The quadrupole interactions at the odine nucleus in Mo/sub 6/S/sub 6/I/sub 2/ and Mo/sub 6/Te/sub 6/I/sub 2/ are small but have opposite signs signifying bonding differences between these compounds.
Date: January 1, 1981
Creator: Subba Rao, G.V.; Niarchos, D.; Shenoy, G.K.; Cashion, J.D.; Hinks, D.; Umarji, A.M. et al.
Partner: UNT Libraries Government Documents Department

Determining criteria for the disposal of iodine-129

Description: The basic consideration in the disposal of the /sup 129/I produced by the nuclear power industry is that humans must be protected from unacceptable radiation risks. Existing standards prescribe maximum concentrations in air and water and, more recently, a maximum release per unit of electrical power production. The global quantity, distribution, and rate of movement of /sup 127/I (natural iodine), naturally produced /sup 129/I, and anthropogenic /sup 129/I are examined. The /sup 129/I released earlier as a result of nuclear activities over the past few decades is not uniformly dispersed. But the possibility of much greater dispersion exists and, therefore, of much greater dilution than was previously attempted. The potential for dilution with respect to either the /sup 129/I concentration or the /sup 129/I//sup 127/I ratio far exceeds the minimum required for acceptable exposure to mankind. For utilizing the dilution principle, it is preferable to package and dispose of /sup 129/I separately from other fission products. The deep ocean is seen to be the logical location for ultimate disposal. A set of 14 basic items is described that can be used to set criteria for storage and disposal of /sup 129/I. It is suggested that preliminary standards be developed on these and perhaps other items to apply to (1) temporary storage and transportation, (2) disposal to a dry environment with a time limitation on calculated behavior, and (3) disposal to the deep ocean with complete release permitted in 10/sup 3/ yr. Early quantification of some of these items will permit better decisions on further research and development needed for iodine removal or control, fixation, and disposal.
Date: October 1, 1980
Creator: Burger, L.L.
Partner: UNT Libraries Government Documents Department

Workshop on photon activation therapy: proceedings

Description: This Workshop was held concurrently with an IAEA Research Coordination Meeting on Exploration of the Possibility of High-LET Radiation for Non-conventional Radiotherapy in Cancer. The Workshop on Photon Activation Therapy (PAT) was given as a special session on April 18, as it was thoght PAT might eventually be found to be attractive to developing countries, which is a major concern of the IAEA. An effort was made to bring together representatives of the various groups known to be actively working on PAT; these included investigators from Sweden and Japan as well as the US. It is hoped that this compendium of papers will be of use to those currently active in this developing field, as well as to those who might join this area of endeavor in the future.
Date: April 18, 1985
Creator: Fairchild, R.G. (ed.)
Partner: UNT Libraries Government Documents Department

Review of radial dose profiles for heavy ions

Description: Average energy deposited per unit mass in a cylindrical shell formed between radial distance r and r + dr from the trajectory of incident ions is defined as the radial dose D(r). Variation of D(r) as a function of radial distance is the radial dose profile. This radial dose profile information has been used by others to develop biophysical models of radiation effects. Radial dose profiles for heavy ions also provide data that can be checked against calculations made by different track structure codes based on continuous slowing down models or Monte Carlo methods. In addition radial dose profiles can also be determined from measured event size distributions. By comparing radial dose from two different experimental techniques, a direct evaluation of different experimental procedures and methods can be made. In this document we review the experimental measurement technique for determination of radial dose profiles, and the experimental data available for different heavy ions at different energies. 15 refs., 5 figs.
Date: January 1, 1987
Creator: Varma, M.N. & Baum, J.W.
Partner: UNT Libraries Government Documents Department

Multiple electron loss cross sections for heavy ions incident on various atomic and molecular gases. [Differential and total cross sections, charge exchange, 20 MeV]

Description: Differential cross sections for charge change resulting from the scattering of 20 MeV /sup 127/I/sup 5 +/ and 20 MeV /sup 35/Cl/sup 4 +/ ions from thin gaseous targets were measured. Total cross sections for multiple electron loss were determined by integration of the differential charge state yields over angle. Cross sections will be presented for /sup 127/I/sup 5 +/ ions and /sup 35/Cl/sup 4 +/ ions on Xe, Ar, and N/sub 2/. Impact parameter analyses of charge fraction data were performed; these analyses depend on the assumed interatomic potential but not on any absolute measurements. The applicability of Bohr, Thomas--Fermi, and Lenz--Jensen potentials with the experimental total cross sections is shown. A different method, using a magnetic quadrupole to focus individual charge states, was used to measure absolute charge state yields of 20 MeV Fe ions emerging within a large acceptance angle from a differentially pumped gas cell of length 9.4 cm/sup 2/ N/sub 2/, Ar, Kr, Xe, and SF/sub 6/ targets were investigated. From the low pressure yields total cross sections for single and multiple electron loss were obtained using an improved version of the initial growth method. 18 references.
Date: January 1, 1978
Creator: Miller, P.D.
Partner: UNT Libraries Government Documents Department

Radiation enhancement with /sup 127/I-deoxyuridine

Description: A technique for radiation enhancement of photon radiotherapy is outlined. High LET radiations in the form of Auger electron distributions are generated by photoactivation of stable iodine incorporated as iodinated deoxyuridine (IdUrd). Of the several halogenated deoxyribonucleosides evaluated, IdUrd was found to be the only thymidine analog providing effective photoactivation. This mechanism is combined with radiation sensitization to produce an overall radiation enhancement. Calculations show that 5% replacement of Tyd in tumor DNA should multiply the biological effectiveness of low energy photons by a factor of approx. 2. Higher replacements would provide higher gains. Enhancement results from chemical sensitization by IdUrd, where it is known that effects of irradiation are multiplied by factors of from approx. 1.5 to 3 as replacement varies from 10 to 50%. Additional enhancement results from the stimulation of Auger cascades in DNA. Five percent replacement has been obtained in human tumor in vivo. Twice that has been obtained in murine tumors. Our data indicates that damage from photoactivation as well as chemical sensitization does not repair. Thus, it is anticipated that use of low dose rates associated with permanent implants of Sm-145 sources (38-45 KeV x-rays; T1/2 = 340 d) will yield an additional increase in therapeutic efficacy by a factor of from 3 to 8, compared to that obtained with acute dose rates.
Date: June 1, 1982
Creator: Fairchild, R.G.
Partner: UNT Libraries Government Documents Department

Determination of low specific activity iodine-129 off-gas concentrations by GC separation and negative ionization mass spectrometry

Description: This document is the final report of the laboratory development of a method for determining the specific activity of the /sup 129/I emitted from a nuclear fuel reprocessing plant. The technique includes cryogenic sample collection, chemical form separation, quantitation by gas chromatography, and specific activity measurement of each chemical species by negative ionization mass spectrometry. The major conclusions were that both organic and elemental iodine can be quantitatively collected without fractionation and that specific activity measurements as low as one atom of /sup 129/I per 10/sup 5/ atoms of /sup 127/I are possible.
Date: September 1, 1983
Creator: Fernandez, S.J.; Rankin, R.A.; McManus, G.J.; Nielsen, R.A.; Delmore, J.E.; Hohorst, F.A. et al.
Partner: UNT Libraries Government Documents Department

Iodine-129 in forage and deer on the Hanford site and other Pacific Northwest locations

Description: Samples of surface soil, litter, forage, and deer (rumen content, muscle, liver, and thyroid gland) were collected from Bend, Oregon; Centralia, Washington; Wenatchee, Washington; the Wooten Game Range near Dayton, Washington; and on or near the Hanford Site, Richland, Washington. The concentrations of /sup 129/I and /sup 127/I were determined using neturon activation techniques. The purpose of the study was to establish the current levels of /sup 129/I in the environs of the Hanford Site prior to the proposed restart of fuel reprocessing at the PUREX plant. The results of this study clearly demonstrated the longevity of /sup 129/I in the biosphere following gaseous release from a nuclear facility. Analyses of thyroid glands showed that deer living within 160 km (Wooten Game Range) of Hanford had elevated levels of /sup 129/I when compared to the more distant Pacific Northwest locations (Centralia, or Bend). Levels of /sup 129/I in deer thyroid from Bend, or Centralia, (15 fCi/g wet weight), were about five times higher than values reported for the central United States, while, Hanford samples were about 2,700 times higher. The average concentration of /sup 129/I in deer thyroids collected at Hanford in 1978 was similar to samples collected 14 years earlier. The concentrations of /sup 129/I in soil, litter, forage, and other deer samples generally decrease in the order: Hanford > Wooten > Wenatchee > Centralia approx. = Bend. This corresponds to an increase in distance from the Hanford Site.
Date: February 1, 1981
Creator: Price, K.R.; Cadwell, L.L.; Schreckhise, R.G. & Brauer, F.P.
Partner: UNT Libraries Government Documents Department

Electron transfer processes in collisions of highly charged energetic (0. 1 to 1. 0 MeV/nucleon) ions with helium atoms

Description: We have investigated charge transfer in collisions of energetic (0.1 - 1 MeV/nucleon) highly charged ions with helium atoms with the principal aim clarifying the nature of two-electron processes. The sensitivity of partial charge-changing cross sections (i.e., single- and double-charge transfer, transfer ionization (TI), and single and double ionization) to core configuration and scaling rules for one- and two-electron processes were investigated with iodine ions (q = 5+ ..-->.. 26+) and uranium ions (q = 17+ ..-->.. 44+) using an ion-charge state, recoil-ion coincidence method. Using zero-degree electron spectroscopy in coincidence with charge transfer, we found that at the higher energies, as in the case of 0.1 MeV/nucleon ions previously reported, TI involves the transfer of two electrons to a higher correlated state followed by loss of one electron to the continuum. In addition, we observe very high Rydberg electrons in coincidence with TI, implying a possible up-down correlation in the pair transfer. In addition, we made measurements of VUV photons emitted at the collision in coincidence with He/sup +/ and He/sup 2 +/ recoils. The results show that TI leads to capture into lower n states than single-charge transfer. 15 refs., 10 figs.
Date: January 1, 1987
Creator: Datz, S.; Hippler, R.; Andersen, L.H.; Dittner, P.F.; Knudsen, H.; Krause, H.F. et al.
Partner: UNT Libraries Government Documents Department