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Whole-body autoradiographic microimaging: Applications in radiopharmaceutical and drug research

Description: The whole-body autoradiographic (WBARG) microimaging technique is used for evaluation of the temporo-spatial distribution of radiolabeled molecules in intact animals as well as to determine the sites of accumulation of parent compounds and their metabolites. This technique is also very useful to determine the metabolism of a compound, toxicity, and effects of therapeutic interventions on the distribution of a compound in the whole body, by studying animals at different time intervals after injection of the radiolabeled compound. This report discusses various aspects of WBARG.
Date: January 1, 1991
Creator: Som, P. & Sacker, D.F.
Partner: UNT Libraries Government Documents Department

Description of an XRF system for multielemental analysis

Description: An X-ray fluorescence (XRF) system which uses radioisotopes in an orthogonal configuration between the source, sample, and detector is described. The advantage of such a system is that for large (bulk) samples or for in vivo measurements the background due to Compton scattering in the sample is minimized. High reproducibility for nonuniform samples is obtained by reducing the sample size and thus the effects of non-uniformity in the spatial response of such a system. Germane to any accurate analytical method is the use of proper mathematical algorithms for data evaluation. The problem is acute, in particular, when photopeaks with low counting statistics are to be analyzed. In the case of a single photopeak on flat, background optimal energy window size, which maximizes the signal-to-noise ratio, for trapezoidal intergration is described. The sensitivity and minimum detection limit at different energies together with background considerations are discussed. 13 refs., 8 figs., 2 tabs.
Date: January 1, 1986
Creator: Wielopolski, L.; Zhang, R. & Cohn, S.H.
Partner: UNT Libraries Government Documents Department

A new apparatus for the study of nuclear Bragg scattering

Description: A new monochromator system has been constructed which provides an energy resolution of 0.005 eV and an angular divergence of 0.4 arc seconds at an energy of 14.413 keV. In conjunction with a highly perfect crystal of isotopically enriched /sup 57/Fe/sub 2/O/sub 3/, a beam of nuclear resonant photons was extracted from the synchrotron continuum with signal to noise ratio of 100:1, and an intensity of >2 quanta/sec. 14 refs., 9 figs.
Date: January 1, 1987
Creator: Siddons, D.P.; Hastings, J.B. & Faigel, G.
Partner: UNT Libraries Government Documents Department

Phenomena at very high spins. [Approx. 70 h-bar; review]

Description: The present talk has three parts: first, a discussion of current ideas about the physics of very high spin states; second, some comments about noncollective behavior up to the highest spins where it is known, approx. 40 h; and finally, a presentation of the newest method for studying collective behavior up to spins of 60 to 70 h. The intention is that the overview presented in the first part will be sufficiently broad to indicate the relationship of the noncollective and collective behavior discussed in the other parts, and to provide some understanding of the compromise in behavior that seems to occur at the very highest spins. 13 figures.
Date: March 1, 1980
Creator: Stephens, F.S.
Partner: UNT Libraries Government Documents Department

Moessbauer effect of europium metal under pressure

Description: The pressure dependence of the magnetic hyperfine field and of the isomer shift of /sup 151/Eu in europium metal has been studied in a diamond anvil pressure cell at low temperatures. In the pressure range 0-12 GPa at 44/sup 0/K (T/sub N/ = 90/sup 0/K), the magnetic hyperfine field changes from -22 T to -8 T while the isomer shift increases from -7.3 to -3.8 mm s/sup -1/ relative to a SmF/sub 3/ source. The changes are interpreted as indicative of a pressure-driven intermediate valence state causing a reduced magnetic moment in Eu. Intermediate valence and magnetic order coexist over the range of pressures studied.
Date: September 1, 1986
Creator: Taylor, R.D. & Farrell, J.N.
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

Cosmic ray half life of sup 54 Mn

Description: A search for the {beta}{sup +} decay of {sup 54}Mn has established an upper limit of 4.4 {times} 10{sup {minus}8} for this branching ratio, and a lower limit of 13.3 for the log ft value for this second forbidden unique transition. Assuming that the {beta}{sup {minus}} decay branch has the same log ft value, then its partial half life must be greater than 4 {times} 10{sup 4} years. Experiments to directly measure the {beta}{sup {minus}} decay rate of {sup 54}Mn are now in progress. 6 refs., 2 figs.
Date: August 1, 1989
Creator: Norman, E.B.; Sur, B.; Vogel, K.R.; Lesko, K.T.; Larimer, R.M. & Browne, E.
Partner: UNT Libraries Government Documents Department

Uptake and distribution of technetium in several marine algae

Description: The uptake or chemical form of technetium in different marine algae (Acetabularia, Cystoseira, Fucus) has been examined and a simple model to explain the uptake of technetium in the unicellular alga, Acetabularia, has been conceptualized. At low concentrations in the external medium, Acetabularia can rapidly concentrate technetium. Concentration factors in excess of 400 can be attained after a time of about 3 weeks. At higher mass concentrations in the medium, uptake of technetium by Acetabularia becomes saturated resulting in a decreased concentration factor (approximately 10 after 4 weeks). Approximately 69% of the total radioactivity present in /sup 95m/Tc labelled Acetabularia is found in the cell cytosol. In Fucus vesiculosus, labelled with /sup 95m/Tc, a high percentage of technetium is present in soluble ionic forms while approximately 40% is bound, in this brown alga, in proteins and polysaccharides associated with cell walls. In the algal cytosol of Fucus vesiculosus, about 45% of the /sup 95m/Tc appears to be present as anionic TcO/sup -//sub 4/ and the remainder is bound to small molecules. 8 references, 5 figures, 1 table.
Date: January 1, 1983
Creator: Bonotto, S.; Gerber, G.B.; Garten, C.T. Jr.; Vandecasteele, C.M.; Myttenaere, C.; Van Baelen, J. et al.
Partner: UNT Libraries Government Documents Department

Modeling and interpretation of two-phase flow and tracer studies from a subbituminous coal seam in the San Juan basin of New Mexico

Description: Field and modeling studies were performed to characterize two-phase flow within the natural cleat structure of an upper Cretaceous subbituminous coal seam. A two borehole pattern with open completion was used in a study of dewatering and tracer residence time distribution. Air was pumped into a five meter thick seam located about 170 meters below the surface. Krypton 85 was used as the airborne tracer. Air inflow and air and water production rates and tracer arrival times were monitored. The field tests were simulated with a two-phase, three component, porous flow code. Results showed that the air inflow and air and water outflow rates and breakthrough times could not be modeled assuming a uniform darcy-type permeability. The use of a pressure dependent permeability did provide, however, a much better match with the field data.
Date: January 1, 1980
Creator: Nuttall, H.E. & Travis, B.J.
Partner: UNT Libraries Government Documents Department

Study of the replacement collision probability in the case of Co inplanted in Al at 4. 2/sup 0/K

Description: Earlier Moessbauer effect experiments on /sup 57/Co diffused in Al show two different positions for the Co-atoms after irradiation of the sample with fast neutrons: substitutional Co and interstitial Co. In order to study the landing dynamics of Co in Al we have implanted /sup 57/Co in Al at 4.2/sup 0/K, at which temperature the Al-interstitials are still immobile. The total implanted dose was 10/sup 14/ at/cm/sup 2/, the implantation energy 85 keV. The Moessbauer spectrum shows one line corresponds to substantial Co-atoms, the other one comes from interstitial Co-atoms (in the <100> Co--Al mixed dumbbell position). The population of the substitutional site, found to be 0.46 +- 0.02, can give information on the interaction potentials between Co--Al and Al--Al when the results are interpreted on the basis of a replacement collision model modified by taking into account a spontaneous trapping volume for the lattice atom recoil, around substitutional Co.
Date: January 1, 1979
Creator: Odeurs, J.; Pattyn, H.; Verbiest, E.; Coussement, R.; Reintsema, S.R. & Brice, D.K.
Partner: UNT Libraries Government Documents Department

Microscopic-macroscopic features in fusion reactions involving light systems

Description: Experimental results obtained at Argonne and elsewhere for the fusion cross-section energy dependence for light to medium weight systems are presented. The most notable features in these data are the observation of (1) oscillatory structure in the fusion cross section excitation function for those systems involving the most tightly bound nuclei in the 1p shell and (2) sudden increases in the maximum fusion cross section for systems which involved nuclei differing only by one or two nucleons. Comparisons of the experimental cross-section behaviors in both the low-energy and high-energy regions with macroscopic model predictions show that significant discrepancies exist. The possible importance of the structure of the projectile and target on this cross-section behavior is discussed. From these data it appears that there is ample evidence that the detailed structure of the projectile and target play an important role in the fusion process. These results indicate that more high-quality data sensitive to these &#x27;&#x27;microscopic&#x27;&#x27; features, and theoretical calculations which attempt to include the detailed structure of the interacting ions are needed for progress in understanding these phenomena.
Date: January 1, 1977
Creator: Kovar, D G
Partner: UNT Libraries Government Documents Department

Properties of neutron-rich nuclei studied by fission product nuclear chemistry. [Review]

Description: A review is given of the properties of neutron-rich nuclei studied by fission product nuclear chemistry and includes the techniques used in elemental isolation and current research on the structure of nuclei near /sup 132/Sn, particle emission, and coexisting structure in both neutron-poor and neutron-rich nuclei. 35 references. (JFP)
Date: September 1, 1979
Creator: Meyer, R.A.; Henry, E.A.; Griffin, H.C.; Lien, O.G. III; Lane, S.M.; Stevenson, P.C. et al.
Partner: UNT Libraries Government Documents Department

/sup 35/Cl and /sup 81/Br nuclear magnetic resonance studies of carbonic anhydrase

Description: /sup 35/Cl NMR studies substantiated the binding of Cl/sup -/ to the Zn(II) of carbonic anhydrase. Zinc-free carbonic anhydrase was prepared and it exhibited essentially no effect on the Cl/sup -/ line width. The net Cl/sup -/ line width increased with temperature. /sup 81/Br NMR was quite similar to /sup 35/Cl in that its relaxation is dominated by quadrupolar interactions.
Date: February 1, 1979
Creator: Ward, R.L.
Partner: UNT Libraries Government Documents Department

Role of the n--p interaction in microscopic calculations of collective motion

Description: A topic of longstanding interest in nuclear structure theory has been the microscopic theory of collective nuclear behavior. There is now a large body of evidence that nuclear shell-model calculations can reproduce rotational behavior which is observed in light nuclei, particularly in the sd shell. The so-called interacting boson model which has been able to describe both rotational and vibrational behavior in intermediate and heavy nuclei, is a truncation scheme for shell-model calculations. An intrinsic assumption of the model is that the shell model is capable of describing observed collective phenomena. Recent papers have suggested that the neutron--proton interaction plays a decisive role in shell-model descriptions of rotational behavior. These arguments on the importance of n--p interaction are summarized. 6 figures, 4 tables. (RWR)
Date: January 1, 1979
Creator: McGrory, J.B.
Partner: UNT Libraries Government Documents Department

Search for magnetism in hcp epsilon-Fe

Description: The results of recent experimental investigation which extends the search for magnetic ordering in the high-pressure, hcp phase of iron (epsilon-phase) to a temperature of 0.030 K are reported. Moessbauer effect measurements were performed in the pressure range from atmospheric pressure to 21.5 GPa on a foil of natural iron (doped with /sup 57/Co). Measurements were made of the properties of both the ..cap alpha..- and epsilon-phase constituents of the sample. No measurable magnetic hyperfine field was observed in the epsilon-phase from any of the spectra at pressures as high as 21.5 GPa and temperatures as low as 0.030 K.
Date: January 1, 1981
Creator: Cort, G.; Taylor, R.D. & Willis, J.O.
Partner: UNT Libraries Government Documents Department

Production of I sup 131

Description: We have reviewed the problem of recovering I{sup 131} from the Separations Process and conclude that recovery is entirely feasible. This report contains recommendations for I{sup 131} recovery offered for consideration and are based on a technical study.
Date: April 17, 1946
Partner: UNT Libraries Government Documents Department

Calculated thickness of tungsten alloy required for specified attenuation of gamma radiation from sup 137 CS

Description: The traditional method of evaluating and calibrating health physics instruments is to use a calibrator that consists of a single high-activity gamma radiation source with different attenuators to select the radiation level desired for tesing. To have accurate radiation intensities inside the calibrator cavity, the attenuators must be designed from precise absorption calculations. This paper reports calculations made to determine the thickness of tungsten alloy metal required for specific attenuation. These calculations include the buildup contribution by secondary scattering radiation, and they are compared to values calculated with the buildup factor omitted. 3 refs., 2 figs., 3 tabs.
Date: January 1, 1991
Creator: Chiles, M.M.; Allin, G.W. & Pace, J.V. III.
Partner: UNT Libraries Government Documents Department

Capsule calorimeter development report

Description: A capsule calorimeter has been designed, fabricated, and tested that is capable of measuring the rate of thermal energy generation of a capsule source with an accuracy of plus or minus five percent over a range of 300 watts to 1,000 watts of power. Three operating modes were investigated. The rate of temperature rise mode of operation was found to be the superior operating mode based on accuracy, time cycle, and simplicity of operation. This mode of operation is recommended for use in the encapsulation plant for performing calorimetric determinations on the strontium and cesium capsules that will be produced in the plant. The heat generation data collected by calorimetry will be used for isotopic assay of the capsule sources. The capsule calorimeter is specifically designed for installation into a remotely operated hot cell.
Date: October 2, 1972
Creator: Hall, J.C.
Partner: UNT Libraries Government Documents Department

M1 transitions between collective levels and F-spin purity

Description: M1 transitions between low-lying collective levels in deformed nuclei are described within the IBM-2 framework. This is done by a special choice of the Hamiltonian which allows a simultaneous fit of energies, E2 and M1 transitions. Finally, the results are interpreted using the F-spin concept. 12 refs., 4 tabs.
Date: January 1, 1987
Creator: von Brentano, P.; Frank, W.; Gelberg, A.; Harter, H.; Krips, W.; Casten, R.F. et al.
Partner: UNT Libraries Government Documents Department

Microscopic analysis of angular momentum projected HFB-states in terms of interacting bosons

Description: Angular momentum- and number-projected Hartree-Fock-Bogoliubov (HFB) wavefunctions for transitional and deformed Rare Earth nuclei are analyzed in terms of Fermion pairs coupled to angular momenta L = 0(S), 2(D), 4(G), ... The Fermion space is truncated to contain only S-D or S-D-G pairs. The variation is carried out before and after angular momentum projection and with different truncations. The influence of the truncation on physical quantities such as moments of inertia, quadrupole moments or pair transfer matrix elements is discussed. 21 references.
Date: December 1, 1984
Creator: Ring, P. & Pannert, W.
Partner: UNT Libraries Government Documents Department

E4 moments for deformed rare-earth and heavy transitional nuclei

Description: Techniques for measuring reduced matrix elements <4/sup +/ parallel M(E4) parallel 0/sup +/>, the interpretation of these data, and the implications for various nuclear models are reviewed and discussed. Actual examples are confined to deformed rare-earth and heavy transitional nuclei. 33 refs., 9 figs.
Date: August 1, 1987
Creator: Baker, F.T.
Partner: UNT Libraries Government Documents Department