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Sample records for 90nb 93mmo 96tc

  1. 96Tc levels populated in the (α,n) reaction

    The levels of odd-odd 96Tc have been investigated using the 93Nb(α,nγ)96Tc reaction at an alpha-beam energy of 14 MeV. The experiments involved singles, gamma-gamma coincidences, detailed excitation functions, gamma-ray angular distributions, measurements of the gamma-ray linear polarization coefficients, and electron internal-conversion coefficients. Spin and parity assignments are given with a high degree of confidence to most of the 105 energy levels, which are interconnected by 251 gamma-ray transitions. In particular, a new energy level at 36.24 keV completes a sextet of lowest lying levels ranging in spin from 2+ to 7+ formed by a coupling of an odd g9/2 proton to an odd d52 neutron. The structure of 96Tc shows some vibrational features coexisting with a significant configuration mixing. Thus, a quartet of nuclei at the onset of a deformation region at A ∼ 100, 94,95Mo and 95,96Tc, provides a challenging ground for testing of the microscopic models and may give further insight into the nature of the neutron-proton interaction in complex nuclei. (14 refs., 2 tabs., 4 figs.)

  2. High Spin States in Vdd-odd Nucleus 90Nb

    CUIXing-zhu; ZHULi-hua; WUXiao-guang; LIGuang-sheng; WENShu-xian; WANGZhi-min; HEChuang-ye; ZHANGZhen-long; MENGRui; MARui-gang; LUOPeng; ZHENGYong; M.M.Ndontchueng

    2003-01-01

    The high spin states of 90Nb were populated through the fusion-evaporation reaction 76Ge(19F,5n)90Nb. The 80 MeV 19F beams was delivered by the HI-13 tandem accelerator in China Institute of Atomic Energy. The 76Ge target is 2.2 mg/cm2 thick and evaporated on 10 mg/cm2 lead backing. The γ-rays from the reaction residues were recorded using 14 Compton suppressed HPGe-BGO spectrometersin γ-γ coincident mode.

  3. 90Nb: potential radionuclide for application in immuno-PET. Development of appropriate production strategy and first in vivo evaluation of 90Nb-labeled monoclonal antibody

    Nuclear medicine is a modern and highly effective tool for the detection and treatment of oncological disease. Molecular imaging based on radiotracers includes single photon emission tomography (SPECT) and positron emission tomography (PET), which provide non-invasive tumor visualization on nano- and picomolar level, respectively. Currently, many novel tracers for more precise discovery of small tumors and metastases have been introduced and are under investigation. Many of them are protein-based biomolecules which nature herself produces as antigens for the eradication of tumor cells. Antibodies and antibody fragments play an important role in tumor diagnostics and treatment. PET imaging with antibodies and antibody fragments is called immuno-PET. The main issue that needs to be addressed is that appropriate radiotracers with half-lives related to the half-lives of biomolecules are needed. The development of novel radiotracers is a multistep, complicated task. This task includes the evaluation of production, separation and labeling strategy for chosen radionuclide. Finally, the biomolecule-radionuclide complex should be stable in time. An equally important factor is the economic suitability of the production strategy, which will lead to a key decision for future application of the developed radionuclide. In recent work, 90Nb has been proposed as a potential candidate for application in immuno-PET. Its half-life of 14.6 hours is suitable for application with antibody fragments and some intact antibodies. 90Nb has a relatively high positron branching of 53% and an optimal energy of β+ emission of 0.35 MeV that can provide high quality of imaging with low dose of used radionuclide. First proof-of-principle studies have shown that 90Nb: (i) can be produced in sufficient amount and purity by proton bombardment of natural zirconium target (ii) can be isolated from target material with appropriate radiochemical purity (iii) may be used for labeling of monoclonal

  4. Level structure of 94,95,96Tc at high spins and shell-model calculations

    High-spin states in the 94,95,96Tc (N=51, 52, and 53) nuclei have been investigated using the 65Cu+36S reaction at a beam energy of 142 MeV. More than 60 new transitions have been identified and placed in their level schemes, which now extend up to spin J≅22(ℎ/2π) and excitation energies Ex≅12 MeV. Spherical shell-model calculations have been performed using different model spaces. A restricted model space, using 88Sr as the core and the π(p1/2,g9/2) ν(d5/2,s1/2) valence orbitals, reproduces the experimental excitation energies up to J≅14(ℎ/2π). The higher-angular-momentum states are dominated by the excitation of a g9/2 neutron across the N=50 magic core, as indicated by large-basis shell model calculations. (c) 1999 The American Physical Society

  5. Separation of {sup 90}Nb from zirconium target for application in immuno-PET

    Radchenko, V.; Roesch, F. [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Filosofov, D.V.; Bochko, O.K.; Lebedev, N.A.; Rakhimov, A.V. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Hauser, H.; Eisenhut, M. [German Cancer Research Center, Heidelberg (Germany). Radiopharmaceutical Chemistry; Aksenov, N.V.; Bozhikov, G.A. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation). Flerov Laboratory of Nuclear Reactions; Ponsard, B. [Belgian Nuclear Research Centre (SCKCEN), Mol (Belgium). Radioisotopes and NTD Silicon Production

    2014-07-01

    Fast progressing immuno-PET asks to explore new radionuclides. One of the promising candidates is {sup 90}Nb. It has a half-life of 14.6 h that allows visualizing and quantifying biological processes with medium and slow kinetics, such as tumor accumulation of antibodies and antibodies fragments or drug delivery systems and nanoparticles. {sup 90}Nb exhibits a positron branching of 53% and an average kinetic energy of emitted positrons of E{sub mean} = 0.35 MeV. Currently, radionuclide production routes and NbV labeling techniques are explored to turn this radionuclide into a useful imaging probe. However, efficient separation of {sup 90}Nb from irradiated targets remains in challenge. Ion exchange based separation of {sup 90}Nb from zirconium targets was investigated in systems AG 1 x 8 - HCl/H{sub 2}O{sub 2} and UTEVA-HCl. {sup 95}Nb (t{sub 1/2} = 35.0 d), {sup 95}Zr (t{sub 1/2} = 64.0 d) and {sup 92m}Nb (t{sub 1/2} = 10.15 d) were chosen for studies on distribution coefficients. Separation after AG 1 x 8 anion exchange yields 99% of {sup 90/95}Nb. Subsequent use of a solid-phase extraction step on UTEVA resin further decontaminates {sup 90/95}Nb from traces of zirconium with yields 95% of {sup 90/95}Nb. A semi-automated separation takes one hour to obtain an overall recovery of {sup 90/95}Nb of 90%. The amount of Zr was reduced by factor of 10{sup 8}. The selected separation provides rapid preparation (< 1 h) of high purity {sup 90}Nb appropriate for the synthesis of {sup 90}Nb-radiopharmaceuticals, relevant for purposes of immuno-PET. Applying the radioniobium obtained, {sup 90/95}Nb-labeling of a monoclonal antibody (rituximab) modified with desferrioxamine achieved labeling yields of > 90% after 1 h incubation at room temperature. (orig.)

  6. Nuclear data for the cyclotron production of 117Sb and 90Nb

    This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90. (authors)

  7. Effect of humic acid on the sorption of technetium on hematite colloids using 95mTc and 96Tc as tracers

    In the present paper the results of studies on the effect of humic acid on the sorption of technetium on hematite with tracers 95mTc (T1/2 = 60 days) and 96Tc (T1/2 = 4.88 days), thereby reaching concentration (∼ 10-12M) comparable to those available in the nature are reported

  8. Level density and spin dependence parameter for 59Ni, 96Tc, 118Sb from the differential cross sections of neutron emission in the (pn)- and (αn) reactions

    The level density and spin dependence parameter for the 59Ni, 96Tc, 118Sb nuclei are determined from the spectra measurement results and neutrons angular distributions in the 56Fe(αn)59Ni, 59Co(pn)59Ni, 93Nb(αn)96Tc, 96Mo(pn)96Tc and 115In(αn)118Sb reactions by the protons energy of 9 and 11 MeV and the α-particles energy of 12.3; 16.3; 18.3 MeV

  9. Equilibrium and pre-equilibrium calculations of cross-sections of (, ) reactions on 89Y, 90Zr and 94Mo targets used for the production of 89Zr, 90Nb and 94Tc positron-emitting radionuclides

    R Baldik; H Aytekin; E Tel

    2013-02-01

    In this study, the pre-equilibrium and equilibrium calculations of cross-sections of 89Y(, ), 90Zr$(p, xn)$ and 94Mo(, ) reactions, which were used for the production of 89Zr, 90Nb and 94Tc positron-emitting radioisotopes, have been investigated. Pre-equilibrium calculations have been performed at different proton incident energies by using the hybrid, geometry-dependent-hybrid and full exciton models. The Weisskopf–Ewing model is used for calculating the equilibrium effects at the same incident energies. The calculated results have been discussed and compared with the experimental results.

  10. Wear measurement using radioactive tracer technique based on proton, deuteron and α-particle induced nuclear reactions on molybdenum

    Highlights: ► Proton, deuteron, 3He and α-particle activation of Mo. ► TLA (thin layer activation). ► Wear measurement. ► Integral production yields. ► Wear curves (specific activity versus penetration depth). - Abstract: Excitation functions of light ion induced nuclear reactions on natural molybdenum have been studied in the frame of a systematic investigation of charged particle induced nuclear reactions on metals for various applications. Excitation functions of 93,94g,94m,95g,95m,96,99mTc, 90,93m,99Mo, 90,91m,92m,95m,95g,96Nb and 88,89Zr were measured up to 50 MeV deuteron energy Tárkányi et al., 2012 [1], 93m,93g,94m,94g,95m,95g,96g,99mTc, 90,93m,99Mo, 90,92m,95m,95g,96Nb and 88,89Zr were measured up to 40 MeV proton energy Tárkányi et al., 2012 [2] and 93m,93g,94m,94g,95m,95g,96g,99mTc, 93m,99Mo, 90Nb, 94,95,97,103Ru and 88Zr were measured up to 40 MeV alpha energy Ditrói et al., 2012 [3] by using the stacked foil technique and activation method. The results for 3He induced reactions on natural Mo were taken from the literature Comparetto and Qaim, 1980 [4]. According to their half-lives, from the above listed radionuclides the 95m,96Tc, 91m,92m,95m,95gNb, 99Mo, 103,97Ru and 88Zr are suitable candidates for wear measurement by using thin layer activation (TLA) method. The goal of this work was to determine the necessary nuclear data for TLA of the above radionuclides and to prove their applicability for wear measurements.

  11. Fission spectrum averaged cross section measurements of some neutron threshold reactions of relevance to medical radionuclide production

    A resume is given of radiochemical measurements of nuclear reaction cross sections relevant to the production of some medically important radionuclides carried out at PINSTECH during the last decade. Systematic studies on fission neutron spectrum averaged cross sections of several threshold reactions, like (n, 2n), (n, p) and (n, α) on titanium, ruthenium, europium and dysprosium for the production of 45Ti, 96Tc, 153Sm and 153Gd are described. (orig.)

  12. E1 transitions between spin-dipole and Gamow-Teller giant resonances

    Rodin, V A

    2000-01-01

    The branching ratios for E1 transitions between the spin-dipole (SD) and Gamow-Teller (GT) giant resonances in $^{90}$Nb and $^{208}$Pb are evaluated. Assuming the main GT-state has the wave function close to that for the "ideal" GT-state, we reduced the problem to calculate the SD and GT strength functions. These strength functions are evaluated within an extended continuum-RPA approach.

  13. New activation cross section data on longer lived radio-nuclei produced in proton induced nuclear reaction on zirconium

    The excitation functions of 96Nb, 95mNb, 95gNb, 92mNb, 91mNb, 90Nb, 95Zr, 89Zr, 88Zr, 86Zr, 88Y, 87mY, 87gY, 86Y were measured up to 70 MeV proton energy by using the stacked foil technique and the activation method. The new data were compared with the critically analyzed experimental data in the literature and with the TALYS based model results in TENDL-2013 library. The possible role of the investigated reactions in the production of medically relevant 90Nb, 95mNb, 89Zr, and 88Y radionuclides is discussed. - Highlights: • Proton induced reactions on natural zirconium up to 65 MeV. • Stacked foil irradiation technique coupled with gamma-spectrometry. • Comparison of experimental data with the nuclear reaction model results in the TENDL-2013 library. • Calculation and comparison of thick target integral yields. • Comparison of the production routes of 90Nb, 95mNb, 89Zr and 88Y medically relevant radioisotopes

  14. Labeling and preliminary in vivo assessment of niobium-labeled radioactive species: A proof-of-concept study.

    Radchenko, Valery; Bouziotis, Penelope; Tsotakos, Theodoros; Paravatou-Petsotas, Mari; la Fuente, Ana de; Loudos, George; Harris, Adrian L; Xanthopoulos, Stavros; Filosofov, Dmitry; Hauser, Harald; Eisenhut, Michael; Ponsard, Bernard; Roesch, Frank

    2016-05-01

    The application of radionuclide-labeled biomolecules such as monoclonal antibodies or antibody fragments for imaging purposes is called immunoscintigraphy. More specifically, when the nuclides used are positron emitters, such as zirconium-89, the technique is referred to as immuno-PET. Currently, there is an urgent need for radionuclides with a half-life which correlates well with the biological kinetics of the biomolecules under question and which can be attached to the proteins by robust labeling chemistry. (90)Nb is a promising candidate for in vivo immuno-PET, due its half-life of 14.6h and low β(+) energy of Emean=0.35MeV per decay. (95)Nb on the other hand, is a convenient alternative for longer-term ex vivo biodistribution studies, due to its longer half-life of (t½=35days) and its convenient, lower-cost production (reactor-based production). In this proof-of-principle work, the monoclonal antibody bevacizumab (Avastin(®)) was labeled with (95/90)Nb and in vitro and in vivo stability was evaluated in normal Swiss mice and in tumor-bearing SCID mice. Initial ex vivo experiments with (95)Nb-bevacizumab showed adequate tumor uptake, however at the same time high uptake in the liver, spleen and kidneys was observed. In order to investigate whether this behavior is due to instability of (⁎)Nb-bevacizumab or to the creation of other (⁎)Nb species in vivo, we performed biodistribution studies of (95)Nb-oxalate, (95)Nb-chloride and (95)Nb-Df. These potential metabolite species did not show any specific uptake, apart from bone accumulation for (95)Nb-oxalate and (95)Nb-chloride, which, interestingly, may serve as an "indicator" for the release of (90)Nb from labeled biomolecules. Concerning the initial uptake of (95)Nb-bevacizumab in non-tumor tissue, biodistribution of a higher specific activity radiolabeled antibody sample did show only negligible uptake in the liver, spleen, kidneys or bones. In-vivo imaging of a tumor-bearing SCID mouse after injection

  15. Study of the half-life of 123I and the determination of possible radionuclidic impurities

    During the process of production of the radiopharmaceutical nuclear reactor or cyclotron, impurities can be generated from biological, chemical and radionuclidic. The development of the present work was to study the half-life of Na123I sample produced in IEN (Institute of Nuclear Engineering) using the technique of gamma-ray spectrometry with germanium detector in order to Identify such impurities. The results Indicate values of half-life consistent with recent publications with a deviation of 0,08% and 0:11% of uncertainty as well as the identification of impurities to radionuclides 95mTc, 96Tc and 121Te. (author)

  16. Spectroscopy of 96-98Ru and neighboring nuclei: shell model calculations and lifetime measurements

    High Spin states in 94,95Mo, 94-96Tc, 96-98Ru and 97,98Rh were populated via the 65Cu(36S,xpyn) reactions at 142 MeV. Level schemes of these nuclei have been extended up to a spin of J ∼ 20ℎ and an excitation energy of Ex∼12 -14 MeV. Information on the high spin structure for 96Tc and 98Rh has been obtained for the first time. Spherical shell model calculations have been performed and compared with the experimental excitation energies. The level structures of the N=51, 52 isotones exhibit single-particle nature even at the highest spins and excitation energies. A fragmentation of intensity into several branches after breaking of the N = 50 core has been observed. There are indications for the onset of collectivity around neutron number N = 53 in this mass region. A sequence of E2 transitions, reminiscent of vibrational degree of freedom, were observed in 98Ru at spins just above the observed N = 50 core breaking. RDM lifetime measurements have been performed to ascertain the intrinsic structures of these level sequences. (author)

  17. Setting of scaling factors and average radioactivity concentration on container-filled and solidified waste packages generated from Kashiwazaki Kariwa Nuclear Power Plants Unit 1-5

    The report evaluates the appropriateness of the point of view addressed from Japan Nuclear Fuel Co., an enterprise in charge of radioactive waste disposal. The low-level radioactive wastes produced from Kashiwazaki Kariwa Power Plants Unit 1 - 5 as in container-filled and solidified packages in 200L drums were investigated for adequateness of using the same scaling factors and confirming the average radioactivity concentration of H-3, C-14, Co-60, Ni-59, Ni-63, Sr-90, Nb-94, Tc-99, I-129, Cs-137, and total alpha-emitting nuclei before sending to Rokkasho radioactive waste storing center. (S. Ohno)

  18. Possible enhancement of magnetic dipole transition strength between Gamow-Teller and isobaric analog states

    The non-energy weighted sum rule of M1 transitions between IAS and GT states is found to be significantly enhanced compared to the sum rule of parent nucleus. Mechanism of this enhancement is explained. Transition strengths between specific states in 48Sc, 90Nb and 208Bi are calculated to investigate whether the enhancement of the sum rule is reflected in these transitions. Measurement of M1 transitions between IAS and GT states is recommended to obtain more information on the spin-isospin response in medium and heavy nuclei. (orig.)

  19. (3He,t) reaction at 80MeV on 90Zr and 208Pb

    An experiment using the 80MeV 3He beam of the ISN cyclotron at Grenoble has been done on a target of 90Zr and another one of 208Bi. The 90Zr and 208Pb IAS angular distributions are fitted by DWBA calculations. For the previously reported Gamow Teller transition centered in 90Nb at 8.4MeV, two components are observed. The first one of M1 type is centered at 7.2MeV, the other one of unknown polarity at 9.7MeV

  20. On the Fermi and Gamow-Teller strength distribution in medium-heavy mass nuclei

    Rodin, V A

    2003-01-01

    The BCS model is incorporated in the Continuum-Random-Phase-Approximation (CRPA) method to formulate a version of the partially self-consistent pn-quasiparticle CRPA (QCRPA) approach. Within the approach the Fermi and Gamow-Teller strength distributions in single- and double- closed-shell nuclei are calculated for a wide excitation energy interval, including the region of the isovector monopole and spin-monopole giant resonances. The isospin and configurational splittings of the Gamow-Teller resonance are also analyzed. The results obtained for $^{90}$Nb, the Sb isotopes and $^{208}$Bi are compared with available experimental data.

  1. Direct-decay properties of charge-exchange spin giant resonances

    Rodin, V A

    2001-01-01

    An extended continuum-RPA approach is applied to describe direct-decay properties of spin giant resonances in $^{208}$Bi and $^{90}$Nb. Partial branching ratios for direct proton decay from these resonances are evaluated. The branching ratio for $\\gamma$-decay from the spin-dipole resonance to the Gamow-Teller resonance (main peak) is estimated. The saturation-like behaviour of the mean doorway-state spreading width in $^{208}$Pb is discussed in connection with the branching ratio for direct proton decay from the spin-monopole resonance and the Gamow-Teller strength distribution.

  2. Time-dependent isotope effect in recoil implantation Pt. 2

    A typical case of time-dependent isotope effect was found in recoil implantation of technetium in tetraphenylporphyrin. When a mixture of metallic molybdenum and tetraphenylporphyrin (free base) was bombarded with 15 MeV deuterons, the difference of chemical distribution between sup(99m)Tc and 95Tc (or 96Tc) was pronounced in the sample which was stored one day after irradiation, whereas no difference was observed just after the irradiation. This effect was ascribed to decay-induced decomposition, by observing behaviours of the purified system of 99Mo-sup(99m)Tc-TPP. The decomposition was not derived directly from the β-decay recoil but from internal excitation associated with the decay. (author)

  3. Country programme review Bangladesh

    A five-expert mission was organized from 21-26 August 1993 and this document reflects the findings and recommendations of the team. Intensive contacts with heads of institutions, scientists and decision making persons in various sectors in the country were co-ordinated by the Bangladesh Atomic Energy Commission. The terms of reference of the mission were: To assess the on-going TC projects; to assist the Bangladesh nationals to finalize the formulation of the new requests for 1995-96 TC programme and to establish priority areas with regard to the introduction of national projects involving accelerated technological transfer in order to catalyze national development plans in specific areas; to examine institutional framework suitable for the introduction of these priority nuclear techniques

  4. Distribution and separation of metallic and radionuclidic impurities in the production of 18F-fluorodeoxyglucose

    In this study the identification, determination and distribution of metallic and radionuclidic contaminants in the synthesis of 18F-fluorodeoxyglucose are presented. Samples of irradiated 18O-enriched water, purification columns (anionic, C18, Al2O3), final product and wastes were examined. Metallic contaminants were determined by ICP-MS and the radionuclide impurities by high resolution germanium gamma-spectrometry. Fifteen radionuclides were identified in the samples. The enriched water contained cationic contaminants (55Co, 56Co, 57Co, 58Co, 57Ni, 52Mn, 7Be) while the anionic (95Tc, 95mTc, 96Tc, 183Re) were mostly retained in the QMA column. The sources of contamination by metals and radionuclides were determined. Results obtained by ICP-MS generally confirmed the radionuclide distribution obtained by gamma spectrometry. (author)

  5. Radionuclide analysis and scaling factors verification for LLRW of Taipower Reactor

    The Atomic Energy Council of the Republic of China (CAEC) final disposal policy for Low Level Radwaste (LLRW) will be carried on in 1996. Institute of Nuclear Energy Research has the contract to develop the Radionuclide analysis method and to establish the scaling factors for LLRW of Taipower reactors. The radionuclides analyzed including: Co-60, Cs-137, Ce-144, γ-nuclides; H-3, C-14, Fe-55, Ni-59, Ni-63, Sr-90, Nb-94, Tc-99, I-129, Pu-238, Pu-239/240, Pu-241, Am-241, Cm-242, Cm-244 α, β and low energy γ nuclides. 120 samples taken from 21 waste streams were analyzed and the database was collected within 2 years. The scaling factors for different kind of waste streams were computed with weighted log-mean average method. In 1993, the scaling factors for each waste stream has been verified through actual station samples. (author)

  6. Stress corrosion cracking behavior in gaseous oxygen of a U-7.5 Nb-2.5 Zr alloy

    Stress corrosion of the alloy U90Nb7.5Zr2.5 in oxygen is studied for temperature between -200C and 1000C under pressure varying from 0.3 x 10-6 MPa to 0.15 MPa. The domain of stress corrosion and cracking kinetics are determined in function of stress intensity, temperature and pressure. Under 0.15 MPa of oxygen embrittlement is observed for the all range of temperature studied and the phenomenon is thermally activated. At room temperature cracks are produced for all tested pressures, influence of pressure on cracking kinetics is low. Auger spectrometry analysis on the surface of cracks shows a surface mechanism to explain alloy embrittlement in gaseous oxygen

  7. Phenomenological model of the clavulanic acid production process utilizing Streptomyces clavuligerus

    A. Baptista-Neto

    2000-12-01

    Full Text Available The kinetics of clavulanic acid production process by Streptomyces clavuligerus NRRL 3585 was studied. Experiments were carried out in a 4 liters bioreactor, utilizing 2 complex media containing glycerol as the carbon and energy source, and peptone or Samprosoy 90NB (soybean protein as nitrogen source. Temperature was kept at 28°C and the dissolved oxygen was controlled automatically at 40 % saturation value. Samples were withdrawn for determination of cell mass (only peptone medium, glycerol and product concentrations. Gas analyzers allowed on line determination of CO2 and O2 contents in the exit gas. With Samprosoy, cell mass was evaluated by determining glycerol consumption and considering the cell yield, Y X/S, as being the same for both cases. Oxygen uptake and CO2 production rates were strongly related to growth and substrate consumption, allowing determination of stoichiometric constants in relation to growth, substrate, oxygen, product and carbon dioxide.

  8. Conversion probabilities of low-energy (ℎω≤3 keV) nuclear transitions in the electron shells of free atoms. Article translated from Journal Yadernye Konstanty (Nuclear Constants). Series: Nuclear Constants, Issue No. 1, 1987

    Conversion of some low-energy transitions (ℎω≤3 keV) in the nuclei 90Nb, 99Tc, 103Ru, 110Ag, 140Pr, 142Pr, 153Gd, 159Gd, 160Tb, 165Tm, 171Lu, 173W, 188Re, 193Pt, 201Hg, 205Pb, 236Pa and 250Bk are investigated for the case of an isolated atom. The conversion transition probabilities are calculated using the electron wave functions, obtained through numerical integration of the Dirac equations in the atomic field within the framework of the Hartree-Fock-Slater method. The calculation is carried out for the normal configuration of the valence band of the aforementioned atoms. The calculation results are tabulated in this paper. (author)

  9. Studies on stabilities of some human chorionic gonadotropin complexes with {beta}-emitting radionuclides

    Maiti, Moumita [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India); Sen, Kamalika [Department of Chemistry, University of Calcutta, 92 APC Road, Kolkata 700009 (India); Sen, Souvik [Malda Town Divisional Railway Hospital, Malda 732102 (India); Lahiri, Susanta, E-mail: susanta.lahiri@saha.ac.i [Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064 (India)

    2011-02-15

    Human chorionic gonadotropin (hCG) is a peptide hormone, whose one of the structural subunits is identical to that of thyroid-stimulating hormone (TSH). As a consequence, the receptors of TSH also act as receptor for hCG hormone. Keeping in mind this interesting property of hCG we have studied the complex formation ability of various no-carrier-added {beta}-emitting isotopes of {sup 61}Cu (3.3 h), {sup 62}Zn (9.2 h), {sup 90}Nb (14.60 h) and {sup 99}Mo (66.02 h) with hCG molecule. Stability of the hCG-M (M=metal ions) complexes was investigated by dialysis with respect to triple distilled water and ringer lactate solution, which has the same composition as extracellular fluid.

  10. On determining the cross section of the supposed pentaquark Θ{sup +} in the reaction pp → Θ{sup +} Σ{sup +} → pK{sup 0} Σ{sup +}

    Schulte-Wissermann, M.; Lehnert, B.; Morgenstern, M.; Freiesleben, H. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); Czodrowski, P. [University of Alberta, Centre for Particle Physics, Department of Physics, Edmonton (Canada)

    2014-07-15

    This paper addresses the problem of how to extract an upper limit on the cross section for Θ{sup +} production via the reaction pp→Θ{sup +}Σ{sup +}, where the Θ{sup +} is assumed to decay into the pK{sup 0} subsystem. Recent data of the COSY-TOF Collaboration, namely the angular distribution of protons in the Σ{sup +}K{sup 0} helicity frame and the invariant mass spectrum of the pK{sup 0} system, were scrutinised with regard to a resonance by applying the profile likelihood method. It is found that the former distribution is best suited for setting an upper limit on the Θ{sup +} production, which varies between 90nb for an assumed Θ{sup +} mass of 1500MeV/c{sup 2} and 56nb for 1540MeV/c{sup 2}. (orig.)

  11. Activation cross sections of deuteron induced reactions on niobium in the 30-50 MeV energy range

    Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.; Ignatyuk, A. V.

    2016-04-01

    Activation cross-sections of deuterons induced reactions on Nb targets were determined with the aim of different applications and comparison with theoretical models. We present the experimental excitation functions of 93Nb(d,x)93m,90Mo, 92m,91m,90Nb, 89,88Zr and 88,87m,87gY in the energy range of 30-50 MeV. The results were compared with earlier measurements and with the cross-sections calculated by means of the theoretical model codes ALICE-D, EMPIRE-D and TALYS (on-line TENDL-2014 and TENDL-2015 libraries). Possible applications of the radioisotopes are discussed in detail.

  12. Possible enhancement of magnetic dipole transitions between Gamow-Teller and isobaric analog states

    A new decay scheme between Gamow-Teller (GT) resonances and isobaric analog states (IAS) by magnetic dipole transitions is studied. The sum rule of M1 transitions between IAS and GT states is found to be significantly enhanced compared to the non-energy-weighted sum rule of the parent state. Calculated enhancement factors can be as large as ∼2.5 for 48Sc and 90Nb, and 1.5 for 208Bi. Transition strengths between specific states are calculated in the Tamm-Dancoff approximation. The interest of measuring M1 transitions between IAS and GT states to obtain information on the spin-isospin response in finite nuclei is stressed. copyright 1995 The American Physical Society

  13. Folding model study of the isobaric analog excitation: isovector density dependence, Lane potential and nuclear symmetry energy

    Khoa, Dao T; Cuong, Do Cong

    2007-01-01

    A consistent folding model analysis of the ($\\Delta S=0, \\Delta T=1$) charge exchange \\pn reaction measured with $^{48}$Ca, $^{90}$Zr, $^{120}$Sn and $^{208}$Pb targets at the proton energies of 35 and 45 MeV is done within a two-channel coupling formalism. The nuclear ground state densities given by the Hartree-Fock-Bogoljubov formalism and the density dependent CDM3Y6 interaction were used as inputs for the folding calculation of the nucleon optical potential and \\pn form factor. To have an accurate isospin dependence of the interaction, a complex isovector density dependence of the CDM3Y6 interaction has been carefully calibrated against the microscopic Brueckner-Hatree-Fock calculation by Jeukenne, Lejeune and Mahaux before being used as folding input. Since the isovector coupling was used to explicitly link the isovector part of the nucleon optical potential to the cross section of \\pn reaction exciting the 0$^+$ isobaric analog states in $^{48}$Sc, $^{90}$Nb, $^{120}$Sb and $^{208}$Bi, the newly paramet...

  14. Investigation of the α-particle induced nuclear reactions on natural molybdenum

    Complete text of publication follows. Cross-sections of alpha particle induced nuclear reactions on natural molybdenum have been studied in the frame of a systematic investigation of charged particle induced nuclear reactions on metals for different applications. The excitation functions of 93mTc, 93gTc(m+), 94mTc, 94gTc, 95mTc, 95gTc, 96gTc(m+), 99mTc, 93mMo, 99Mo(cum), 90Nb(m+), 94Ru, 95Ru, 97Ru, 103Ru and 88Zr were measured up to 40 MeV alpha energy by using a stacked foil technique and activation method. The main goals of this work were to get experimental data for accelerator technology, for monitoring of alpha beam, for thin layer activation technique and for testing nuclear reaction theories. The experimental data were compared with critically analyzed published data and with the results of model calculations, obtained by using the ALICE-IPPE, EMPIRE and TALYS codes (TENDL-2011). Yield versus energy curves are calculated from the measured data (Figs. 1-4) for the radioisotopes having special importance in one of the application fields.

  15. Investigation of the α-particle induced nuclear reactions on natural molybdenum

    Highlights: ► Excitation function measurement of α-particle induced reactions on natural molybdenum up to 40 MeV. ► Model code calculations with EMPIRE-II, EMPIRE3.1, ALICE and TALYS. ► Integral production yield calculation. ► Comparison with deuteron and proton production. ► Monitor reactions for α-irradiations. - Abstract: Cross-sections of alpha particle induced nuclear reactions on natural molybdenum have been studied in the frame of a systematic investigation of charged particle induced nuclear reactions on metals for different applications. The excitation functions of 93mTc, 93gTc(m+), 94mTc, 94gTc, 95mTc, 95gTc, 96gTc(m+), 99mTc, 93mMo, 99Mo(cum), 90Nb(m+), 94Ru, 95Ru,97Ru, 103Ru and 88Zr were measured up to 40 MeV alpha energy by using a stacked foil technique and activation method. The main goals of this work were to get experimental data for accelerator technology, for monitoring of alpha beam, for thin layer activation technique and for testing nuclear reaction theories. The experimental data were compared with critically analyzed published data and with the results of model calculations, obtained by using the ALICE-IPPE, EMPIRE and TALYS codes (TENDL-2011).

  16. Fetoplacental transport of various trace elements in pregnant rat using the multitracer technique

    The placenta functions as the barrier between fetus and mother, providing means of regulation of heat exchange, respiration, nutrition, and excretion for the fetus. In this paper, the multitracer technique was applied to study the maternal transport of trace elements via the placenta to the fetus. In this experiment, the multitracer solution used contained the following nuclides: 7Be, 22Na, 46Sc, 48V, 52Mn, 59Fe, 56Co, 65Zn, 67Ga, 74As, 75Se, 84Rb, 85Sr, 87Y, 88Zr, 96Tc, 101mRh, and 103Ru. We examined the time dependence of the uptake amounts about various elements. From these results, we observed a large difference in the time dependencies between elements and the elements were classified into three groups. Group I elements, such as Be, Sc, V, As, Y, Zr, Tc, Rh, and Ru, are transported to the placenta from the maternal blood and only accumulates in the placenta. Group II elements, such as Na, Co, Ga, Rb, and Sr, are transported to the placenta from the maternal blood and accumulate in the placenta, fetus, and amniotic fluid. Group III elements, such as Mn, Fe, Zn, and Se, are transported to the placenta from the maternal blood and mainly accumulate in the fetus. From these results, it was considered that the placenta is a highly selective filters because essential elements such as Group III elements are readily transported from the placental membrane to the growing fetus, whereas nonessential metals such as Group I elements have difficulty penetrating the placental barrier that protects the fetus from the toxic effects of these elements. (author)

  17. Investigation on the determination of disposal critical nuclides in waste from PWR power plants. Task 3: characterization of radioactive waste forms. A series of final reports (1985-1989) - no.45

    An R and D programme has been conducted in Belgium on the main waste streams arising from the operation of PWR power plants, in order to assay, both in a practical and reliable way, the concentrations of a number of longer-lived nuclides such as C-14, Ni-59, Ni-63, Sr-90, Nb-94, Tc-99, I-129, Cs-135, Cs-137 and the transuranium elements. The aim was to evaluate the possibility of deducing the concentrations of the longer-lived 'critical' nuclides from the data on easily measurable 'key' nuclides such as Co-60 and Cs-137, e.g. by gamma spectrometry on conditioned drums. As an additional verification, some of these conditioned drums were core drilled and the samples analyzed destructively. The conclusions of the investigations may be summarized as follows: for homogeneously embedded waste, the key nuclides Co-60 and Cs-137 can be assessed with satisfactory precision by gamma spectrometry; most of the critical nuclides can only be determined by destructive analysis after complex preparation of the waste samples; for I-129 and Tc-99, and to a lesser extent for Sr-90 and total alpha activity, the coherence of the results obtained so far is poor - further efforts are needed to improve the analytical methods for these elements; certain critical nuclides, such as the corrosion products, correlate well with the key nuclides - for most of the measured fission products, clear correlations could not be established; on the basis of the activities measured, Ni-63, Ni-59, C-14, Tc-99, I-129 and total alpha appear to be important for the classification of the PWR wastes. 23 figs., 28 refs

  18. Antigenicity and diagnostic potential of vaccine candidates in human Chagas disease.

    Shivali Gupta

    Full Text Available BACKGROUND: Chagas disease, caused by Trypanosoma cruzi, is endemic in Latin America and an emerging infectious disease in the US and Europe. We have shown TcG1, TcG2, and TcG4 antigens elicit protective immunity to T. cruzi in mice and dogs. Herein, we investigated antigenicity of the recombinant proteins in humans to determine their potential utility for the development of next generation diagnostics for screening of T. cruzi infection and Chagas disease. METHODS AND RESULTS: Sera samples from inhabitants of the endemic areas of Argentina-Bolivia and Mexico-Guatemala were analyzed in 1(st-phase for anti-T. cruzi antibody response by traditional serology tests; and in 2(nd-phase for antibody response to the recombinant antigens (individually or mixed by an ELISA. We noted similar antibody response to candidate antigens in sera samples from inhabitants of Argentina and Mexico (n=175. The IgG antibodies to TcG1, TcG2, and TcG4 (individually and TcG(mix were present in 62-71%, 65-78% and 72-82%, and 89-93% of the subjects, respectively, identified to be seropositive by traditional serology. Recombinant TcG1- (93.6%, TcG2- (96%, TcG4- (94.6% and TcG(mix- (98% based ELISA exhibited significantly higher specificity compared to that noted for T. cruzi trypomastigote-based ELISA (77.8% in diagnosing T. cruzi-infection and avoiding cross-reactivity to Leishmania spp. No significant correlation was noted in the sera levels of antibody response and clinical severity of Chagas disease in seropositive subjects. CONCLUSIONS: Three candidate antigens were recognized by antibody response in chagasic patients from two distinct study sites and expressed in diverse strains of the circulating parasites. A multiplex ELISA detecting antibody response to three antigens was highly sensitive and specific in diagnosing T. cruzi infection in humans, suggesting that a diagnostic kit based on TcG1, TcG2 and TcG4 recombinant proteins will be useful in diverse situations.

  19. Microscale mechanical characterization of materials for extreme environments

    Ozerinc, Sezer

    Nanocrystalline metals are promising materials for applications that require outstanding strength and stability in extreme environments. Further improvements in the desirable mechanical properties of these materials require a better understanding of the relationship between their microstructure and grain boundary deformation behavior. Previous molecular dynamics simulations suggested that solute additions to grain boundaries can enhance the strength of nanocrystalline metals, but there has been a lack of experimental studies investigating this prediction. This dissertation presents mechanical and microstructural characterization of nanocrystalline Cu alloys and demonstrate that addition of Nb solutes to grain boundaries greatly enhances the strength of Cu. The measured hardness of Cu90Nb10 alloy is 5.6 GPa which is more than double the hardness of nanocrystalline pure Cu. Microstructural characterization through transmission electron microscopy and energy-dispersive X-ray spectroscopy on these alloys indicates a strong correlation between the grain boundary composition and the hardness. Variation of measured hardness with measured grain boundary composition is in very good agreement with previous molecular dynamics simulation predictions. The results of this work provide experimental evidence that grain boundary doping enhances the strength of nanocrystalline Cu far beyond that predicted by classical Hall-Petch strengthening and decreasing grain boundary energy through solute additions is the key to reaching theoretical strength in nanocrystalline metals. Irradiation induced creep is a deformation mechanism that takes place under combined stress and particle bombardment. Effective characterization of this phenomenon on nanostructured materials is crucial for the assessment of their potential use in next generation nuclear power plants. Direct measurements of irradiation induced creep under MeV-heavy ion bombardment have not been feasible until recently due to the

  20. Nuclear structure - classic and exotic

    were studied by in-beam γ-ray spectroscopy methods. The results for nuclei such as 83 Sr, 85 Y, 86 Zr, indicated that the collectivity of the yrast states increases when N decreases towards the middle of the shell. Thus, it appeared that N (or Z) = 38 or 40 does not always behave as a quasi-magic number. To understand these results we performed Nilsson-Strutinsky calculations for nuclei in the A ∼ 80 - 100 mass region. These calculations reproduced well the sudden onset of deformation known in the A ∼ 100 region (Sr, Zr and Mo isotopes). Most of our recent work has been centered on odd-odd A ∼ 90 nuclei which are not so well known. It is interesting to study such nuclei with only a few nucleons outside the closed shell Z(N) = 50. The maximum spin that can be constructed by aligning the individual spins of the valence nucleons is not so large, so that one can easily excite higher spin states which should result from nucleons excited across the closed shell.The 94 Nb nucleus has been populated in the same reaction with 96 Tc, as the (α3n) channel. Its γ-rays have been assigned by coincidence with α-particles, and with neutrons (multiplicity of 3). The γ-rays thus assigned were found in coincidence with the known transition of 78.7 keV between a low-lying (7+) state and the 6+ ground state, so that they were placed above this state. High-spin states have been studied in the 97 Mo nucleus with the reaction 82 Se(19 F,p3nγ) at 68 MeV. The main experimental result is the observation of the νh11/2 quasi-band structure up to the 31/2- state at Ex = 5.5 MeV. The systematic behaviour of this structure along the isotopic and isotonic sequences is presented. The structure of the 97 Mo is discussed in terms of the Interacting Boson-Fermion Model-1. In-beam γ-ray spectroscopic studies of proton emitters are hampered by high fragmentation of the fusion cross section and, in heavier systems, by competition from fission. For this reason, a novel technique, the recoil