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Saturation Absorption Spectroscopy
Published in Pradip Narayan Ghosh, Laser Physics and Spectroscopy, 2018
Rubidium is an alkali metal with two isotopes Rb85 and Rb87, with natural abundances of 72.2% and 27.8% respectively. They have nuclear spins I = 5/2 for Rb85 and I = 3/2 for Rb87. The ground state electronic configuration is the completely filled core of inert gas atom Kr surrounded by a single valence electron in the 5s state with the electron configuration 1s(2)2s(2)2p(6)3s(2)3p(6)3d(10)4s(2)4p(6)5s.
Distributed Multi-Antenna SAR Time and Phase Synchronization
Published in Wen-Qin Wang, Multi-Antenna Synthetic Aperture Radar, 2017
High-precision frequency sources have undergone tremendous advances during the decades since the advent of the first laboratory cesium beam clock in 1955. Thousands of atomic clocks, such as the cesium beam and the optically pumped rubidium sources manufactured by industry, are routinely used today. The ultrastable hydrogen master is also used on a large scale for very demanding applications. Quality quartz-crystal-controlled oscillators have also shown such progress in stability that they can sometimes compete with rubidium clocks [335].
Rb, 37]
Published in Alina Kabata-Pendias, Barbara Szteke, Trace Elements in Abiotic and Biotic Environments, 2015
Alina Kabata-Pendias, Barbara Szteke
Rubidium (Rb) is a silvery-white soft metal of group 1 in the periodic table of elements, with properties similar to alkali metals. The Earth’s crust contains Rb within the range of 90–110 mg/kg. Its higher contents are in acidic igneous rocks, <100–200 mg/kg, and in sedimentary argillaceous rocks, <120–200 mg/kg. The mean Rb content in coal is 25 mg/kg, but it may be concentrated up to 140 mg/kg.
Theoretical determination of vapour–liquid equilibrium pressure and vaporisation enthalpy of rubidium in the temperature range of 700 K–2017 K based on a modified Redlich–Kwong equation of state
Published in Phase Transitions, 2022
Kamala Rajagopal, Balasubramanian Ramasamy
The vapour pressure of rubidium has been determined, based on a modified Redlich–Kwong equation of state coupled with the Maxwell’s equal area construction method, in the temperature range of 700 K–2017 K. The vapour pressure of rubidium obtained in this work agrees well with the literature data. In this work, four linear correlations have been formulated and analysed in different temperature ranges to predict the vapour pressure of rubidium. The formulated vapour pressure correlation IV, compared to the literature data, has the MAPE%, absolute fraction of variance, coefficient of correlation R2 and Adjusted R2 are of 1.7681%, 0.9997%, 0.9992% and 0.9992%, respectively. Hence, the correlation with nomenclature IV (Table 3) is recommended to determine the vapour pressure of rubidium in the temperature range of 700 K–2017 K. The reduced vapour pressure curvature for rubidium has a maximum of 3.5274 at the temperature of 1209 K, i.e. about 1.26 times its normal boiling point. At 1209 K, the vapour pressure of rubidium is 591.68 kPa. Based on the obtained vapour pressure of rubidium, the vaporisation enthalpy of rubidium has been determined in a wide range of temperature.