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To reach commercial viability for fuel cells, one needs to develop active and robust Pt-free electrocatalysts. Ag has great potential to replace Pt as the catalyst for oxygen reduction reaction...

Thermodynamic properties of lead species in aqueous solution are collected. The chemical equilibria between various forms of Pb(II) are considered. The speciation diagrams for the equilibria 4[PbOH]+(aq) ⇄ [Pb4(OH)4]4+(aq) and 2[Pb3(OH)4]2+(aq) ⇄ [Pb6(OH)8]4+(aq), and the thermodynamic activity - pH diagram of Pb(II) species are plotted. Basic chemical and electrochemical equilibria for lead are calculated. The potential - pH diagram for Pb - H2O system is revised.

Henry's law constant data for the noble gases helium, neon, argon, krypton, xenon and radon in the pure solvents water, methanol, ethanol and propan-2-ol are predicted over a wide temperature range by molecular simulation. Furthermore, gas solubility measurements are carried out for neon, krypton and xenon in propan-2-ol, yielding experimental Henry's law constant values that are employed, together with data from literature, to evaluate present simulation results. Suitable molecular force eld models are identied for each binary system and new models for helium and neon are presented. By examining the entire set of binary systems, a characteristic trend of the solubility behavior concerning the molecular size of the solutes and solvents is identied. The I present work contributes consistent Henry's law constant data for 24 binary solutesolvent pairs over the entire relevant temperature range and improves the database considerably.

2 Kafedra analitičeskoj i fizičeskoj himii, himičeskij fakul'tet, Čelâbinskij gosudarstvennyj universitet, ulica Brat'ev Kaširinyh 129, 454001 Chelyabinsk, An experimental and computational study on the solubility of argon in propan-2-ol at high temperatures and pressures was performed. The following values of the Henry's law constant for the solution of argon in propan-2-ol were obtained: 58 « 3 MPa at 480 K, 99 « 3 MPa at 420 K, and 114 « 2 MPa at 360 K.Keywords: Argon solubility | Propan-2-ol | Henry's law constant Studying phase equilibria and constructing phase diagrams is not only an important fundamental problem, but also an essential task for chemical engineering and technology. 1,2However, even for simple binary systems the process of collecting and systematising that type of thermophysical data is far from completion. Usually, both experimental and computational approaches are used to obtain the necessary information about the phase behavior of systems under consideration.Noble gases have found wide application in medicine, environmental chemistry, and lighting. The solubility and phase behavior of noble gases in water and organic solvents was studied rather widely, 3 however, for many systems the available information is not complete. The Henry's law constant for the solution of argon in propan-2-ol was previously reported only in a limited temperature range. 47 This communication describes an experimental and computational study on the solubility of argon in propan-2-ol at high temperatures.The experimental setup for the present gas solubility measurements 8 is the same as employed in earlier studies. The following substances were used: argon (CAS number 7440-59-7) supplied by Air Liquide in a gas tank under a pressure of 30 MPa with a volume fraction of 99.9999% and propan-2-ol (CAS number 67-63-0) supplied by Honeywell Riedelde Haën with a purity of >99.9%. The measuring cell was filled with argon and heated to about 20 K above the desired measuring temperature, and then the desired amount of propan-2-ol was added into it. When the mixture achieved a homogeneous state, the cell was slowly cooled down with the aim to reach the saturated liquid state. 9 The experiments were carried out at the temperatures 360, 420, and 480 K. The density of argon and propan-2-ol as well as the saturated vapor pressure of pure propan-2-ol at these temperatures were calculated with equations of state. 10,11 The experimental raw data together with the values used in the processing of them are presented in the Supporting Information. The resulting dependence of the phase equilibrium pressure on the mole fraction of argon in liquid propan-2-ol at 360, 420, and 480 K is depicted in Figure 1.As can be seen, the isotherms may be well approximated by straight lines. The slopes of these lines calculated with the least-squares technique were used to estimate the Henry's law constant at these temperatures; the estimated values together with their uncertainties are listed in Table 1.Several approaches have been proposed in the l...