This paper reports on the application of molten chloride salts, NaCl and CaCl2, for extraction of potassium from Oxley rock (ultrapotassic microsyenite) mined in Western Australia based on both ...experimental kinetic and thermochemical analysis. The reaction parameters of temperature, time, and salt to ore ratio were systematically analyzed, and a potassium extraction of more than 90% and 87% using CaCl2 and NaCl, respectively, was obtained. In this paper, thermochemical equilibrium models have also been developed which show excellent agreement with experimental data and also allow one to predict how the system deviates from equilibrium where the maximum potassium extraction can be obtained. Also, this study offers a potential comparison between the use of NaCl and CaCl2 in terms of potassium extraction and reaction mechanism. Different mineralogical studies have been conducted to characterize the ore and also to understand the reaction principle of the ore with NaCl and CaCl2.
We report the first measurements of the absolute ionization yield of nuclear recoils in liquid xenon, as a function of energy and electric field. Independent experiments were carried out with two ...dual-phase time-projection chamber prototypes, developed for the XENON dark matter project. We find that the charge yield increases with decreasing recoil energy, and exhibits only a weak field dependence. These results are the first unambiguous demonstration of the capability of dual-phase xenon detectors to discriminate between electron and nuclear recoils down to 20 keV, a key requirement for a sensitive dark matter search.
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