• Title/Summary/Keyword: nuclear reactions

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ACTIVATION ANALYSIS OF ENVIRONMENTAL SAMPLES USING THE MT-25 MICROTRON OF THE FLNR

  • Maslov, O.D.;Belov, A.G.;Starodub, G.Ya.;Dmitriev, S.N.
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.815-820
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    • 1995
  • Instrumental neutron and gamma activation analysis of coal and combustion products, determination of platinum content in natural samples by radiochemical gamma activation analysis and high-sensitive track method of thorium determination has been studied with the use of the MT-25 microtron.The optimal conditions for complete elemental analysis of coal and combustion products, isolation and determination of platinum and thorium are recommended.

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New Nuclear Fusion for Our Second Generations

  • Ho-Jin Choi;Koan-Sik Joo
    • Proceedings of the Safety Management and Science Conference
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    • 1999.11a
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    • pp.421-424
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    • 1999
  • In this short report (before the authors would like to introduce an important application for one of the techniques of complex angular momentunm, say, Regge Pole approach, to nuclear fusion reaction for Light-ions: it will be reported in forthcoming papers), two kinds of thermalnuclear fusion reaction sources are introduced and discussed (A) the case of fusion: the production of neutron and target of Deuteron and (B) the case of fusion: the production of proton and target of Deuteron. Nuclear fusion reactions for Light-ions , such as the thermalnuclear energy sources and fuel cycles, are already well known. Fusion reactions are widely known as being extremly important and nationally vital (in point of view of nuclear weapons we must reconsider seriously development and building of such dangerous weapons) for our next generations in the future. This paper (a topics in review) is concerned with a simple introduction about a new nuclear fusion reaction of the above case of (B) for the second generation. Typical thermalnuclear fusion reactions which result in the release of huge amount of energy are nuclear stripping reactions:

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Radiation damage to Ni-based alloys in Wolsong CANDU reactor environments

  • Kwon, Junhyun;Jin, Hyung-Ha;Lee, Gyeong-Geun;Park, Dong-Hwan
    • Nuclear Engineering and Technology
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    • v.51 no.3
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    • pp.915-921
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    • 2019
  • Radiation damage due to neutrons has been calculated in Ni-based alloys in Wolsong CANDU reactor environments. Two damage parameters are considered: displacement damage, and transmutation gas production. We used the SPECTER and SRIM computer codes in quantifying radiation damage. In addition, damage caused by Ni two-step reactions was considered. Estimations were made for the annulus spacers in a CANDU reactor that are located axially along a fuel channel and made of Inconel X-750. The calculation results indicate that the transmutation gas production from the Ni two-step reactions is predominant as the effective full power year increases. The displacement damage due to recoil atoms produced from Ni two-step reactions accounts for over 30% out of the total displacement damage.

Theoretical study of cross sections of proton-induced reactions on cobalt

  • Yigit, Mustafa
    • Nuclear Engineering and Technology
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    • v.50 no.3
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    • pp.411-415
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    • 2018
  • Nuclear fusion may be among the strongest sustainable ways to replace fossil fuels because it does not contribute to acid rain or global warming. In this context, activated cobalt materials in corrosion products for fusion energy are significant in determination of dose levels during maintenance after a coolant leak in a nuclear fusion reactor. Therefore, cross-section studies on cobalt material are very important for fusion reactor design. In this article, the excitation functions of some nuclear reaction channels induced by proton particles on $^{59}Co$ structural material were predicted using different models. The nuclear level densities were calculated using different choices of available level density models in ALICE/ASH code. Finally, the newly calculated cross sections for the investigated nuclear reactions are compared with the experimental values and TENDL data based on TALYS nuclear code.

INVESTIGATION ON MATERIAL DEGRADATION OF ALLOY 617 IN HIGH TEMPERATURE IMPURE HELIUM COOLANT

  • Kim, Dong-Jin;Lee, Gyeong-Geun;Jeong, Su-Jin;Kim, Woo-Gon;Park, Ji-Yeon
    • Nuclear Engineering and Technology
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    • v.43 no.5
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    • pp.429-436
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    • 2011
  • The corrosion of materials exposed to high temperature helium in a very high temperature reactor is caused by interaction with the impurities in the helium. This interaction then induces high temperature mechanical deterioration. By considering the effect of the impurity concentration on material corrosion, a long-term coolant chemistry guideline can be determined for the range of impurity concentration at which the material is stable for a long time. In this work, surface reactions were investigated by analyzing the thermodynamics and the experimental results for Alloy 617 exposed to controlled impure helium at $950^{\circ}C$. Moreover, the surfaces were examined for the Alloy 617 crept in air and in uncontrolled helium, which was explained by possible surface reactions.

NUCLEAR DATA MEASUREMENT OF 186RE PRODUCTION VIA VARIOUS REACTIONS

  • Bidokhti, Pooneh Saidi;Sadeghi, Mahdi;Fateh, Behrooz;Matloobi, Mitra;Aslani, Gholamreza
    • Nuclear Engineering and Technology
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    • v.42 no.5
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    • pp.600-607
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    • 2010
  • Rhenium-186, having a half-life of 90.64 h, is an important radionuclide, used in metabolic radiotherapy and radio immunotherapy. $^{186}Re$ hydroxyethylidene diphosphonate (HEDP) is a new compound used for the palliation of painful skeletal metastases. Its production is achieved via charged-particle-induced reactions; the data are available in EXFOR library. For the work discussed in this paper, production of $^{186}Re$ was done via $^{nat}W(p,n)^{186}Re$ nuclear reaction. Pellets of $^{nat}W$ were used as targets and were irradiated with 15, 17.5, 20, 22.5, 25 MeV proton beams at 5 ${\mu}A$ current. The radiochemical separation was performed by the ion exchange chromatography method. The production yield achieved at 25 MeV was 1.91 $MBq{\cdot}{\mu}A^{-1}{\cdot}h^{-1}$. Excitation functions for the $^{186}Re$ radionuclide, via $^{186}W(p,n)^{186}Re$ and $^{186}W(d,2n)^{186}Re$ reactions were calculated by ALICE-ASH and TALYS-1.0 codes to validate and fit the experimental data and to obtain a recommended set of data for $^{186}W(p,n)^{186}Re$ reaction. Required thickness of the targets was obtained by SRIM code for each reaction.

Calculation of Proton-Induced Reactions on Tellurium Isotopes Below 60 MeV for Medical Radioisotope Production

  • Kim, Doohwan;Jonghwa Chang;Yinlu Han
    • Nuclear Engineering and Technology
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    • v.32 no.4
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    • pp.361-371
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    • 2000
  • The 123Te(p,n)123I, 124Te(p,n)124I and 124Te(p,2n)123I reactions, among the many reaction channels opened, are the major reactions under consideration from a diagnostic purpose because reaction residuals as the gamma emitters are used for most radiophamaceutical applications involving radioiodine. Based on the available experimental data, the absorption cross sections and elastic scattering angular distributions of the proton-induced nuclear reaction on Te isotopes below 60 MeV are calculated using the optical model code APMNK. The transmission coefficients of neutron, proton, deuteron, trition and alpha particles are calculated by CUNF code and are fed into the GNASH code. By adjusting level density parameters and the pair correction values of some reaction channels, as well as the composite nucleus state density constants of the pre-equilibrium model, the production cross sections and energy-angle correlated spectra of the secondary light particles, as well as production cross sections and energy distributions of heavy recoils and gamma rays are calculated by the statistical plus pre-equilibrium model code GNASH. The calculated results are analysed and compared with the experimental data taken from the EXFOR. The optimized global optical model parameters give overall agreement with the experimental data over both the entire energy range and all tellurium isotopes.

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Halogen Exchange Reactions of Cinnamyl Halides

  • Lee, Bon-Su;Lee, Ikchoon
    • Nuclear Engineering and Technology
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    • v.1 no.2
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    • pp.87-90
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    • 1969
  • Halogen exchange reactions of trans-cinnnamyl chloride and bromide with radioactive chloride, bromide and iodide ions in acetone have teen studied. Relative nucleophilicity of halide ions and relative leaving ability have been discussed invoking the principle of HSAB.

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