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Showing 1 to 20 of 66 for “"nuclides"”.
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Heavy nuclides in cosmic radiation.
Massachusetts Institute of Technology. Dept. of Physics. Thesis. 1969. B.S.
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Surface exposure geochronology using cosmogenic nuclides : applications in Antarctic glacial geology
… the apparent attenuation lengths for the two nuclides supports previous suggestions that the 26A1/10Be ratio does not change with depth and therefore can be used as an independent chronometer. 3He profiles in 0.5-0.7 mm and 1.0-1.3 mm grains in one of the cores have scale lengths of 135 ± 6 …
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Surface exposure geochronology using cosmogenic nuclides : applications in Antarctic glacial geology
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, and the Woods Hole Oceanographic Institution, 1994.
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Dating of alluvial fans from NW Argentina using cosmogenic nuclides and optically stimulated luminescence technique
Alluvial fans are important geomorphic markers and sedimentary archives of tectonic and climatic changes. Hence, basins providing perfect studying conditions can often be found in arid regions due to the low weathering impact and thus well preservation of sedimentary features. Twelve samples for …
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Landscape evolution and preservation of ice over one million years old quantified with cosmogenic nuclides 26Al, 10Be, and 21Ne, Ong Valley, Antarctica
… at least 0.9 Mya to 1.5 Mya. Concentrations of nuclides in the bottom of the second drift suggest that local sublimation rates have increased slightly in the past 40-150 Kya. These observations imply that the ice below the middle drift is the oldest undisturbed glacier ice currently known on …
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Interactions of nucleons: their role in understanding the sun's origin, composition, and source of energy
… the utilization of the "Cradle of the Nuclides" in deciphering the Sun. The "Cradle of the Nuclides" is the nuclear energy surface of all 2,850 known nuclides presented as three-dimensional (3-D) plots of mass or atomic number versus charge density versus average energy per …
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First on-line mass measurements at SHIPTRAP and mass determinations of neutron-rich Fr and Ra isotopes at ISOLTRAP
… Its aim are precision studies of transuranium nuclides produced in a fusion reaction and separated by SHIP. The current set-up for high-precision mass measurements consists of three main functional parts: (i) a gas cell for stopping the energetic ions from SHIP, (ii) radiofrequency quadrupole …
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Minor actinide waste disposal in deep geological boreholes
… was considered, paying particular attention to nuclides whose decay energy and half lives were of relative significance to the minor actinide waste as a whole. Thermal Analysis was performed based on a reference borehole design, by Ian C. Hoag. The strategy of the thermal analysis is aimed at …
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A new ion beam cooler and buncher for ISOLTRAP and mass measurements of radioactive argon isotopes
… It is set up to measure the mass of short-lived nuclides with a relative accuracy delta m / m of typically 1* 10^-7. In this work an ion beam cooler and buncher based on a linear radio frequency quadrupole trap has been installed and characterized. By this the overall efficiency of the ISOLTRAP …
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Flux-Independent Uncertainty Propagation of Nuclear Cross Section Data Using the Windowed Multipole Formalism
… uncertainty information is only available for nuclides for which resonance parameter uncertainty is available. A least squares approach is developed to convert continuous energy cross section uncertainties to WMP parameter uncertainties. The approach is used to generate WMP covariances for …
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Studies of alpha-radioactivity in the marine environment
… published literature relating to alpha-emitting nuclides in sea water and in marine organisms is surveyed in Chapter 1. As a first step in the investigation, the total alpha-activity of some 400 samples of marine life was determined using the thick-source alpha-particle detection technique. The …
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Transmutation rates in the annulus gas of pressure tube water reactors
… under high neutron fluxes, annulus gas nuclides undergo different nuclear transformations generating new composition of the gas that might have different physical properties which are undesirable for the annulus system. In addition, gas nuclides become radioactive and lead to an increase …
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MCODE-3 : time-dependent depletion isotopics with MCNP-5 and SCALE-6.1
… input model. MCODE-2 only updates a fraction of nuclides' cross sections, the rest default to a pre-compiled library. Finally, while MCODE-2.2 was written in ANSI C, MCODE-3's main function has been rewritten in the Python scripting language. MCODE's preproc, mcodeout, and mcnpxs programs have …
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Capture cross sections of In¹¹⁵ and I¹²⁷ in the Kev region
… neutron capture cross sections for the two nuclides for neutron energies up to 100 kev. It was also possible to obtain the resonance integral of In¹¹⁵ I¹²⁷ relative to that of I and the s- and p- wave neutron strength functions of both nuclides.
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Cenozoic tectonic and geomorphic evolution of the Red River Region, Yunnan Province, China
… depth dependence data for multiple cosmogenic nuclides from a single site to constrain an erosion history. This method is applied in the Dry Valleys region of Antarctica.
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Study of radio frequency inductively coupled thermal plasma torch (RF ICPT) for radioactive waste treatment: thermoplastics - polyethylene and polyvinyl chloride (PVC)
… volume of RW. The presence of radioactive nuclides in PVC and PE waste originating from NPPs and their plastic nature (non-bio-degradable characteristics) present two challenges at once. To solve the challenges presented by such plastic RW, a thermal plasma waste treatment approach was …
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Novel Resonance Self-Shielding Methods for Nuclear Reactor Analysis
… fitting method to find the effect of interfering nuclides on the subgroup levels of a primary nuclide, allowing mutual self-shielding effects to be treated natively inside the subgroup method without increasing algorithmic complexity. The latter is a hybrid of the subgroup method and ultrafine …
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Studies of neutron inelastic scattering in crystal and liquid scintillators
… contained or loaded in the scintillators. The nuclides included those of iodine, cesium, lanthanum, holmium, praseodymium and bismuth. investigations showed that the technique was feasible for crystal and liquid scintillators, and indicated the study or 12 7I iri sodium iodide crystal to be the …
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Direct mass measurements beyond the proton drip-line
… uncertainties of about 10-8. The masses of nine nuclides were measured for the first time. Four of them (144Ho, 145Ho, 147Tm and 148Tm) were determined to lie beyond the proton drip-line. The data were included into the Atomic Mass Evaluation (AME) and showed generally good agreement with …
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The Borexino experiment : test of the purification systems and data analysis in the Counting Test Facility
… in Borexino in order to tag and remove 11C nuclides on a one-by-one basis. Furthermore, I implemented and tested such technique on the CTF data.
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