Results 241 to 250 of about 4,032,505 (279)

Neutron Diffusion in a Temperature Gradient

Nuclear Science and Engineering, 1962
>The space energy distribution of neutrons diffusing in a source-free, nonabsorbing medium possessing a temperature gradient is obtained by solving the appropriate Boltzmann equation to a second order approximation using the expansion technique of Chipman and Enskog.
J. R. L. de Ladonchamps, L. M. Grossman
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Temperature Equilibrium of C-Neutrons

Nature, 1937
THE slow neutrons leaving a block of paraffin wax, containing a source of fast neutrons, mostly possess thermal energies. The existence of such thermal neutrons has been established by the discovery1 that the temperature T of the paraffin has an influence on the activities induced in various elements.
O. R. FRISCH, H. VON HALBAN, JØRGEN KOCH   +2 more
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Neutron Diffraction Study of Water At High Temperature

Europhysics Letters (EPL), 1992
Neutron diffraction measurements on water at T = 523 K are presented. The comparison with room temperature data shows an evident weakening of the tetrahedral coordination. This effect has been accurately simulated by an ensemble of polarizable water molecules, interacting via the NEMO (Non Empirical Molecular Orbital) potential model.
U. Buontempo, POSTORINO, Paolo, M. A. Ricci, A. K. Soper   +3 more
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Low-Temperature Neutron Moderation

Physical Review Letters, 1960
Measurements on an energy level in the microwave spectrum of water are discussed. The inelastic cross section for scattering of 0.005 ev neutrons from HO/sub 1/2/ at room temperature was estimated to be 8 barns. (C.J.G.)
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Effects of temperature on the structure of neutron stars at high temperature

General Relativity and Gravitation, 2017
In Newtonian physics, higher temperature leads to higher thermal pressure, which provides stronger support against the gravitational contraction of stars. However, in the temperature range of tens of MeV involved in the evolution of a proto-neutron star or a higher massive neutron star, the effects of temperature are richer.
Liang-gui Zhu, Jun-Li Lu, Li Wang
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Neutron scattering at nK temperatures

Neutron News, 1991
Abstract The study of nuclear magnetic order in Copper is the most ambitious and difficult neutron scattering experiment ever performed at Ris⊘. Beside expensive hardware, approximately 50man-months of scientific work, 24 months of beam time and 10000 litres of liquid He had to be invested before we could even expect to discover whether the experiment ...
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Slowing Down Spectrum and Neutron Temperature in a Thermal Neutron Flux Density Standard

Metrologia, 1966
Epithermal and thermal flux parameters for the thermal flux density standard at the National Research Council have been measured to allow a more accurate calculation of activation rates. The epithermal spectrum is found to follow a E-0.95 law, where E is the neutron energy.
Geiger, K. W., van der Zwan, L.
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Temperature measurement by neutron resonance radiography

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1989
Abstract We present a new method of data analysis for determination of temperature from the Doppler broadening of neutron resonance absorption cross sections. The method is model independent and simple to use. It has been applied to measurements on samples of rhenium and tantalum and has given temperatures to an accuracy better than ±1°C.
J. Mayers, G. Baciocco, A.C. Hannon
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A low-temperature Weissenberg camera for neutrons

Journal of Applied Crystallography, 1981
The construction and performance of a neutron Weissenberg camera for temperatures down to 4 K is described. Exposure times are similar to the X-ray case. The background from the cryostat walls can be eliminated. Examples of applications in the fields of magnetic structures which are incommensurate with their chemical unit cells, crystallographic phase ...
D. Hohlwein, A. F. Wright
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Analysis of neutron-temperature oscilations in neutron multiplying systems with delayed neutrons

2017
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Vodyanitskii, A.A., Rudakov, V.A.
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