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Works: 3 works in 5 publications in 1 language and 5 library holdings
Publication Timeline
Most widely held works by HEBREW UNIV JERUSALEM (Israel) MICROWAVE DIV
Physics of vibronic transitions in the spectra of rare earth ions in crystals ( Book )
2 editions published between 1966 and 1967 in English and held by 2 libraries worldwide
Vibronic transitions due to the existence of a gadolinium ion adjacent to a H( - ) ion in CaF2 were investigated. The association of the RE(3+) and the H( - ) ion in the host lattice is manifested by: (1) The appearance of new infra-red absorption frequencies which are not observed in undoped and hydrogenated CaF2. The frequencies depend on the particular RE ion doping. (2) Observation of new electronic transitions in the near U.V. of gadolinium due to new sites adjacent to an H( - ) ion. (3) Observation of vibronic transitions separated from the corresponding parent transitions of the RE ion by the infra-red absorption frequency of the localized H( - ). The IR, electronic and vibronic spectra are strongly dependent on the concentration of the RE doping, the particular dopant and the mode of annealing. Conclusions can be derived from comparison of hydrogenated and deuterated crystals. (Author)
Optical Measurements and Microwave Measurements Behind Shock Waves ( Book )
2 editions published between 1968 and 1971 in English and held by 2 libraries worldwide
The Mach velocity, shock tube attenuation and the maximum test time have been measured in two narrow shock tubes of 1 inch and 1/2 inch diameter. The apparatus is described. The results are compared with theories of Mirels, Roshko and Russel. The results are also compared with experimental results on large cross-sectional shock tubes. It is shown that for pressures of 5 Torr or less the narrow shock tube attenuation and maximum test time fits within a geometric scaling factor those of large cross-sectional tubes. At pressures of 10 Torr and higher partial turbulent flow can explain the experimental results. (Author)
Effects of cross-sectional area change on the speed of a shock wave ( Book )
1 edition published in 1966 in English and held by 1 library worldwide
An experimental study of the effect of convergent and divergent nozzles with area changes of 4:1, 1:4 and 1:8 on the moderate shock speed is presented. The results are compared with the theoretical predictions of the linear and steady state theories. When the experimental values are corrected for viscous effects, it is found that near the exit of the nozzle the Mach speed approximates the values of the linear theory. Far downstream the Mach speed approaches to the steady state values. Superimposed on this gradual change are maxima and minima in the Mach speed. These fluctuations are functions of P4, P1, M and the angle of the taper section. These maxima and minima can be explained to arise from interference effects between the transmitted and re-reflected shock waves. (Author)
English (5)
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