Outstanding performance of PIM-1 membranes towards the separation of fluorinated refrigerant gases

The recycling of depleted high global warming mixtures of fluorinated gases (F-gases) with close-boiling or azeotropic behavior requires advanced separation processes to obtain effectively the pure components. Herein, several types of PIM-1 membranes were tested for the first time towards the separation of hydrofluorocarbons and hydrofluoroolefins, showing extraordinarily high permeability coefficients for the value-added difluoromethane (R-32), up to 4100 barrer, coupled with high selectivity for the F-gas pairs of interest. Additionally, the solubility of selected F-gases in PIM-1 was measured and fitted to the dual-mode and Guggenheim, Anderson and de Boer sorption models. The separation performance of the standard PIM-1 and a highly branched PIM-1 was examined with the mixture R-410A (containing R-32 and pentafluoroethane R-125) to assess the influence of the membrane topology on the mixed-gas permeation properties over time (physical aging). Considering that the branched PIM-1 membrane was the least impacted by the aging phenomena, it was used to recover high purity R-32 (concentration in the permeate side as high as 98.9 vol % was achieved) from refrigerant gas mixtures R-410A and R-454B (mixture of R-32 and R-1234yf) in continuous long-term experiments. Results showed the great potential of PIM-1 membranes for the separation of R-32 from refrigerant mixtures collected from end-of-life equipment.This research is supported by project PID2019-105827RB-I00 funded by MCIN/AEI/10.13039/501100011033. F.P. and S.V.G.H. acknowledge the support of the Spanish State Research Agency and the Spanish Ministry of Science and Innovation (grants IJC2020-043134-I and PRE2020-093568, respectively). A.B.F and P.M.B acknowledge EPSRC Grant ep/v047078/1 (SynHiSel). P.G. is supported by Grant RYC2019-027060-I funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”

Tris[4,4′-(ethene-1,2-di­yl)dipyridinium] deca­vanadate dihydrate

The asymmetric unit of the title compound, (C12H12N2)3[V10O28]·2H2O, contains one half of a deca­vanadate anion, one and a half trans-1,2-bis­(4-pyridinio)ethene cations and one water mol­ecule. The V10O28 groups are involved in a three-dimensional hydrogen-bonding network through Ow—H⋯O, N—H⋯O and C—H⋯O inter­actions

Board Composition, Political Connections and Performance in State-Owned Enterprises

This paper analyses the effects of board composition on the behaviour of a sample of 114 Italian local public utilities, for which information about 1630 directors during 1994-2004 has been collected. This period is particularly interesting because of the legal changes that forced many firms to alter their juridical form and allowed the entrance of private investors. We investigate whether board size and/or board composition do affect decisions about employment and how they ultimately impact on performance. Our main findings indicate that politically connected directors dominate boards of directors in Italian public utilities, exerting a positive and significant effect on employment, and impacting negatively on performance

Board Composition, Political Connections and Performance in State-Owned Enterprises

This paper analyses the effects of board composition on the behaviour and performance of a sample of 114 Italian local public utilities, for which information about 1630 directors during 1994-2004 has been collected. This period is particularly interesting because of the legal changes that forced many firms to alter their juridical form and allowed the entrance of private investors. We investigate whether board size and/or board composition do affect decisions about employment and how they ultimately impact on performance. Our main findings indicate that politically connected directors, representing the state or the local municipality, dominate boards of directors in the Italian public utilities in the period under investigation. Politically connected directors exert a positive and significant effect on employment, while they impact negatively on performance

Board Composition, Political Connections and Performance in State-Owned Enterprises

This paper analyses the effects of board composition on the behaviour and performance of a sample of 114 Italian local public utilities, for which information about 1630 directors during 1994-2004 has been collected. This period is particularly interesting because of the legal changes that forced many firms to alter their juridical form and allowed the entrance of private investors. We investigate whether board size and/or board composition do affect decisions about employment and how they ultimately impact on performance. Our main findings indicate that politically connected directors, representing the state or the local municipality, dominate boards of directors in the Italian public utilities in the period under investigation. Politically connected directors exert a positive and significant effect on employment, while they impact negatively on performance

Board composition, political connections, and performance in state-owned enterprises

This article analyses the effects of board composition on the behavior of a sample of 114 Italian local public utilities, for which information about 1630 directors during 1994\u20132004 has been collected. This period is particularly interesting because of the legal changes that forced many firms to alter their juridical form and accommodated the entrance of private investors. We investigate whether board size and/or board composition do affect decisions about employment and how they ultimately impact performance. Our main findings indicate that politically connected directors, who dominate boards of directors in Italian public utilities, exert a positive and significant effect on employment, and have a negative impact on performance