Hu Niu

A simple ratiometric and colorimetric chemosensor for the selective detection of fluoride in DMSO buffered solution.

A derivative of squaramide (cyclobuta[b]quinoxaline-1, 2(3H, 8H)-dione) has been synthesized for the ratiometric and colorimetric sensing of F(-) in aqueous solution in competitive fashion. With F(-), probe 1 showed a highly selective naked-eye detectable color change along with a characteristic UV-Vis absorbance over other tested ions, which probably originates from the deprotonation occurred between 1 and F(-), as proved by the (1)H NMR titration experiments and DFT calculations.

Dissolution Properties of Dihydroxylammonium 5,5ʹ-Bistetrazole-1,1ʹ-diolate and Disodium 5,5ʹ-Bistetrazole-1,1ʹ-diolate in Water

The dissolution and thermochemical properties of dihydroxylammonium 5,5ʹ-bistetrazole-1,1ʹ-diolate (TKX-50) and its intermedium disodium 5,5ʹ-bistetrazole-1,1ʹ-diolate ([Na2(H2O)4]BTO) in water at 298.15 K were studied using a C-80 Calvet microcalorimeter. Empirical formulae for the calculation of the molar enthalpies of dissolution (ΔdissH), relative partial molar enthalpies (ΔdissHpartial), and relative apparent molar enthalpies (ΔdissHapparent) were deduced by the experimental results of the dissolution processes of TKX-50 and [Na2(H2O)4]BTO in water. Finally, the corresponding kinetic equations describing the dissolution processes were dα/dt = 10−2.95(1 − α)0.64 for the dissolution of TKX-50 in water and dα/dt = 10−2.76(1 − α)1.07 for the dissolution of [Na2(H2O)4]BTO in water.

Pressure characteristics and safety performance of TKX-50 decomposition in confined space

ABSTRACT The pressure characteristics and safety performance of dihydroxylammonium 5,5ʹ-bistetrazole-1,1ʹ-diolate (TKX-50) decomposition were studied in confined space by using the accelerating rate calorimeter (ARC). The effects of the heating rate and the sample amount on the safety performance were investigated. The experiment results revealed that high heating rate was harmful to the safety performance of TKX-50. The decomposition mechanism did not change when using different amounts of sample in the range between 47.5 and 72.5 mg. After ignition, TKX-50 exhibited better safe performance than RDX and HMX.