BF3 Complexing Phosphate/Phosphonate Ionic Liquids: Synthesis, Characterization and Thermophysical Properties.

A new group of BF3 complexing phosphate/phosphonate ionic liquids (ILs) [Emim][X(BF3)2] (X=dimethyl phosphate, diethyl phosphate, methyl phosphonate, and ethyl phosphonate) were synthesized and characterized. Key thermophysical properties of the new complex ionic liquids, including density, viscosity, conductivity, surface tension, solid-liquid phase transition, and thermal stability were determined and compared with those of [Emim][X]. Some other important thermophysical properties such as isobaric thermal expansion coefficient, molecular volume, standard molar entropy, and lattice potential energy were obtained from measured density data, and the free volume was estimated by a linear equation presented in this article, while critical temperature, normal boiling temperature, and enthalpy of vaporization were estimated from measured surface tension and density data. Furthermore, Fragility study shows that [Emim][X(BF3)2] should be considered as fragile liquids, while [Emim][X] could be considered as extremely fragile liquids. The ionicity of [Emim][X(BF3)2] was predicted by Walden rule, and the result shows that these ILs fit well with Walden law. The key features of these complex ILs are their extremely low glass transition (-95.33~-98.46 °C) without melting, considerably low viscosities (33.876~58.117 mPa ⋅ s), and high values of free volume fraction (comparable to [Omim][BF4], [Emim][NTf2], and [Emim][TCB]).

A new 1,2,3-triazole and its rhodamine B derivatives as a fluorescence probe for mercury ions.

A newly synthesized compound, 5-methyl-1-phenyl-1H-1,2,3-triazole-4- carboxylic acid (MPC) was analyzed for its quantum chemical parameters and theoretical spectrum by computational chemistry. The calculated spectrum was in accord with the experimental measurements in a great degree. Then MPC was successfully designed and synthesized to a novel rhodamine B derivative RMPC. The RMPC exhibited about a 4000-fold increase in fluorescence intensity in the presence of Hg2+ ions over most other competitive metal ions. The triazole appended colorless chemodosimeter RMPC turns to pink upon the complex formation only with Hg2+ ions as a 1: 2 M ratio and enables naked-eye detection. The coordination mechanism of turning on/off fluorescence for Hg2+ ions were well proposed by explaining Hg2+ inducing the ring-opened rhodamine B moiety. The fluorescence imaging experiments of Hg2+ in HeLa cell demonstrated that the probe was labeled and it could be used in biological systems.

A secure and fair joint E-lottery protocol.

The attractive huge prize causes people to adore lotteries. Due to the very small probability of winning prizes, the players can enhance their probability of winning by using the method of joint purchase. In spite of many lottery schemes having been proposed, most e-lottery schemes focus on the players' privacy or computation overhead rather than support a joint purchase protocol on the Internet. In this paper, we use the multisignature and verifiable random function to construct a secure and fair joint e-lottery scheme. The players can check the lottery integrity, and the winning numbers can be verified publicly.