73 research outputs found
Discovery of the actinium, thorium, protactinium, and uranium isotopes
Currently, 31 actinium, 31 thorium, 28 protactinium, and 23 uranium isotopes
have so far been observed; the discovery of these isotopes is discussed. For
each isotope a brief summary of the first refereed publication, including the
production and identification method, is presented.Comment: Accepted for publication in Atomic Data Nuclear Data Table
Compilation of Giant Electric Dipole Resonances Built on Excited States
Giant Electric Dipole Resonance (GDR) parameters for gamma decay to excited
states with finite spin and temperature are compiled. Over 100 original works
have been reviewed and from some 70 of which more than 300 parameter sets of
hot GDR parameters for different isotopes, excitation energies, and spin
regions have been extracted. All parameter sets have been brought onto a common
footing by calculating the equivalent Lorentzian parameters. The current
compilation is complementary to an earlier compilation by Samuel S. Dietrich
and Barry L. Berman (At. Data Nucl. Data Tables 38(1988)199-338) on
ground-state photo-neutron and photo-absorption cross sections and their
Lorentzian parameters. A comparison of the two may help shed light on the
evolution of GDR parameters with temperature and spin. The present compilation
is current as of January 2006.Comment: 31 pages including 1 tabl
Gottes Wort ist nicht gebunden : Predigt über 2. Timotheum 2, 9 gehalten bei dem Missions- und Bibelfest zu Düsseldorf am 8. August 1852
von Herm. Hingmann, ev. Pastor in WaldIn Fraktu
Radon emission rate and analysis of its influencing parameters
The geological and structural conditions define the radon situation inside a building. While
the geological realities can be specified by the content of radium-226 and the ratio of radon-222 emitted from the
ground the structural conditions are defined by the tightness of the building envelope. The radon concentration
inside has an unsteady character, which is caused by meteorological conditions outside and the air change rate
(ACH or ACR), which in turn is influenced by the residents’ behaviour such as venting and heating. For the
assessment of the radon exposition, it is necessary to perform measurements for a long time. An approach to
reduce this time by eliminating the inhabitants influence on the radon concentration is the radon emission rate,
also known as radon entry rate. This variable is based on the measurement of the radon concentration and the
parallel determination of the air change rate via a tracer gas method, the result expresses a released activity per
time. Due to their noisy character, it is necessary to apply a smoothing algorithm to the input parameters. In
addition to mean values, the use of window functions, known from digital signal processing, was analysed. For
the verification of the whole calculation procedure, simulations and measurements under defined conditions
were used. Furthermore, measurements in an uninhabited house showed proof of the capability of the assessment
of the radon potential. First examinations of influencing parameters of the radon emission rate showed
a possible dependence on the temperature difference inside and outside the building
Radon emission rate and analysis of its influencing parameters
The geological and structural conditions define the radon situation inside a building. While
the geological realities can be specified by the content of radium-226 and the ratio of radon-222 emitted from the
ground the structural conditions are defined by the tightness of the building envelope. The radon concentration
inside has an unsteady character, which is caused by meteorological conditions outside and the air change rate
(ACH or ACR), which in turn is influenced by the residents’ behaviour such as venting and heating. For the
assessment of the radon exposition, it is necessary to perform measurements for a long time. An approach to
reduce this time by eliminating the inhabitants influence on the radon concentration is the radon emission rate,
also known as radon entry rate. This variable is based on the measurement of the radon concentration and the
parallel determination of the air change rate via a tracer gas method, the result expresses a released activity per
time. Due to their noisy character, it is necessary to apply a smoothing algorithm to the input parameters. In
addition to mean values, the use of window functions, known from digital signal processing, was analysed. For
the verification of the whole calculation procedure, simulations and measurements under defined conditions
were used. Furthermore, measurements in an uninhabited house showed proof of the capability of the assessment
of the radon potential. First examinations of influencing parameters of the radon emission rate showed
a possible dependence on the temperature difference inside and outside the building
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