TY - JOUR A1 - Mohammady, M. Hamed A1 - Auffèves, Alexia A1 - Anders, Janet T1 - Energetic footprints of irreversibility in the quantum regime JF - Communications Physics N2 - In classical thermodynamic processes the unavoidable presence of irreversibility, quantified by the entropy production, carries two energetic footprints: the reduction of extractable work from the optimal, reversible case, and the generation of a surplus of heat that is irreversibly dissipated to the environment. Recently it has been shown that in the quantum regime an additional quantum irreversibility occurs that is linked to decoherence into the energy basis. Here we employ quantum trajectories to construct distributions for classical heat and quantum heat exchanges, and show that the heat footprint of quantum irreversibility differs markedly from the classical case. We also quantify how quantum irreversibility reduces the amount of work that can be extracted from a state with coherences. Our results show that decoherence leads to both entropic and energetic footprints which both play an important role in the optimization of controlled quantum operations at low temperature. In classical thermodynamics irreversibility occurs whenever a non-thermal system is brought into contact with a thermal environment. Using quantum trajectories the authors here establish two energetic footprints of quantum irreversible processes, and find that while quantum irreversibility leads to the occurrence of a quantum heat and a reduction of work production, the two are not linked in the same manner as the classical laws of thermodynamics would dictate. KW - entropy production KW - quantum mechanics KW - thermodynamics Y1 - 2020 U6 - https://doi.org/10.1038/s42005-020-0356-9 SN - 2399-3650 VL - 3 IS - 1 SP - 1 EP - 14 PB - Springer Nature CY - London ER - TY - JOUR A1 - Walkowiak, Jacek A1 - Lu, Yan A1 - Gradzielski, Michael A1 - Zauscher, Stefan A1 - Ballauff, Matthias T1 - Thermodynamic analysis of the uptake of a protein in a spherical polyelectrolyte brush JF - Macromolecular rapid communications N2 - A thermodynamic study of the adsorption of Human Serum Albumin (HSA) onto spherical polyelectrolyte brushes (SPBs) by isothermal titration calorimetry (ITC) is presented. The SPBs are composed of a solid polystyrene core bearing long chains of poly(acrylic acid). ITC measurements done at different temperatures and ionic strengths lead to a full set of thermodynamicbinding constants together with the enthalpies and entropies of binding. The adsorption of HSA onto SPBs is described with a two-step model. The free energy of binding Delta Gb depends only weakly on temperature because of a marked compensation of enthalpy by entropy. Studies of the adsorbed HSA by Fourier transform infrared spectroscopy (FT-IR) demonstrate no significant disturbance in the secondary structure of the protein. The quantitative analysis demonstrates that counterion release is the major driving force for adsorption in a process where proteins become multivalent counterions of the polyelectrolyte chains upon adsorption. A comparison with the analysis of other sets of data related to the binding of HSA to polyelectrolytes demonstrates that the cancellation of enthalpy and entropy is a general phenomenon that always accompanies the binding of proteins to polyelectrolytes dominated by counterion release. KW - Spherical polyelectrolyte brushes KW - proteins KW - ITC KW - thermodynamics KW - enthalpy-entropy compensation (EEC) Y1 - 2019 U6 - https://doi.org/10.1002/marc.201900421 SN - 1022-1336 SN - 1521-3927 VL - 41 IS - 1 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Scott, James M. A1 - Konrad-Schmolke, Matthias A1 - O'Brien, Patrick J. A1 - Günter, Christina T1 - High-T, low-P formation of rare olivine-bearing symplectites in variscan eclogite JF - Journal of petrology N2 - Extremely rare veinlets and reaction textures composed of symplectites of olivine (similar to Fo(43-55)) + plagioclase +/- spinel +/- ilmenite, associated with more common pyroxene + plagioclase and amphibole + plagioclase varieties, are preserved within eclogites and garnet pyroxenites in the Moldanubian Zone of the Bohemian Massif. Thermodynamic modelling integrated with conventional geothermometry conducted on an eclogite reveals that the symplectite-forming stage occurred at high T (similar to 850 degrees C) and low P (< 6 and > 2 center dot 5 kbar). The development of the different symplectite types reflects reactions that took place in micro-scale domains. The breakdown of high-P garnet controlled the formation of olivine-bearing and amphibole + plagioclase symplectites, whereas breakdown of high-P omphacite led to formation of pyroxene + plagioclase symplectites. In addition, post-eclogite facies but pre-symplectite stage porphyroblastic amphibole and phlogopite were also replaced by olivine-bearing symplectites. Material transfer calculations and thermodynamic modelling indicate that the formation of different symplectite types was linked despite their different bulk compositions. For example, the olivine-bearing symplectites gained Fe +/- Mg, whereas adjacent amphibole + plagioclase and pyroxene + plagioclase symplectites show losses in Fe and Mg; Al, Si and Ca were also variably exchanged. The olivine-bearing symplectites were particularly sensitive to Na despite the small concentration of this element. In eclogites where Na was readily available, the plagioclase composition in the olivine-bearing symplectites shifted from pure anorthite to bytownite, with the less calcic feldspar partitioning Si and inhibiting the formation of orthopyroxene. This regional high-T, low-P granulite-facies symplectite overprint may have been caused by advective heat loss from rapidly exhumed high-T, high-P granulitic bodies (Gfohl Unit) that were emplaced into and over the middle crust (Monotonous and Varied Series) during Carboniferous continent-continent collision. KW - olivine KW - symplectite KW - eclogite KW - thermodynamics KW - Variscan Y1 - 2013 U6 - https://doi.org/10.1093/petrology/egt015 SN - 0022-3530 SN - 1460-2415 VL - 54 IS - 7 SP - 1375 EP - 1398 PB - Oxford Univ. Press CY - Oxford ER -