Caesium nitrate

Abstract: The synthesis and extraction properties of a copolymer comprised of a 10:1 molar ratio of methyl methacrylate (MMA) and a methacrylate functionalized benzocrown-6-calix[4]arene are reported. Under aqueous-dichloromethane liquid–liquid extraction conditions, the copolymer displayed an enhanced selectivity for caesium over sodium and potassium (in the form of their picrate salts) as compared to an appropriate small molecule analogue. Further, the copolymer was capable of removing caesium nitrate from aqueous solution in the presence of various other anionic (e.g., F−, Cl−, and SO4−) and cationic species (e.g., K+ and Na+). The ability of this polymeric system to extract inorganic caesium salts into dichloromethane from aqueous media scaled with the relative hydration energies (ΔhydG°) of each anion studied (i.e., NO3− > Br− ≫ Cl− or F−).

Abstract: The effect of nitrate uptake on the subcellular distribution of tissue nitrate in 2-5 mm maize root tips was investigated by two complementary methods. First a novel in vivo analysis using 133 Cs nuclear magnetic resonance (NMR) was used to demonstrate changes in the cytoplasmic and vacuolar pools during caesium nitrate uptake. This method depended on interpreting the nitrate-induced changes in the positions of the cytoplasmic and vacuolar caesium signals. The assignment of the signals was confirmed by using in vivo 39 K NMR to observe the displacement of cytoplasmic potassium into the vacuole during caesium uptake, and in vivo 133 Cs NMR to observe the displacement of cytoplasmic caesium into the vacuole during potassium uptake. Secondly nitrate-selective microelectrodes were used to quantify the change in the cytosolic nitrate activity that occurred in the outermost cells of root tips under the same conditions. Both methods showed that the detected nitrate pool increased over a period of 8-10 h in the presence of 10 mM nitrate and it is concluded that the data provide support for the view that homeostasis in the cytosolic and cytoplasmic nitrate pools is not necessarily an invariant characteristic of root tips.

Abstract: Absorption spectra of RbNO 3 and CsNO 3 nitrate single crystals have been studied. It is stated that the photo-induced absorption in UV-irradiated samples consists of three bands. Thermal annealing and photo-bleaching (>310 nm) of the bands have been investigated. It is found that two low-energy bands are due to peroxynitrite and the high-energy band is due to the complex [NO 2 − ⋯O]. The mechanism for the nitrite ion formation from the peroxynitrite ion and the complex has been proposed.