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Dynamic combinatorial chemistry has emerged as a promising tool for the discovery of complex receptors in supramolecular chemistry. At the heart of dynamic combinatorial chemistry are the reversible reactions that enable the exchange of building blocks between library members in dynamic combinatorial libraries (DCLs) ensuring thermodynamic control over the system. If more than one reversible reaction operates in a single dynamic combinatorial library, the complexity of the system increases dramatically, and so does its possible applications. One can imagine two reversible reactions that operate simultaneously or two reversible reactions that operate independently. Both these scenarios have advantages and disadvantages. In this contribution, we show how disulfide exchange and boronic ester transesterification can function simultaneous in dynamic combinatorial libraries under appropriate conditions. We describe the detailed studies necessary to establish suitable reaction conditions and highlight the analytical techniques appropriate to study this type of system.

The paper presents a new mathematical model of the processes of charging and discharging a thermochemical energy storage (TChES) reactor with a high potential for effective application in a residential building. The model is an intermediate approach between lumped-element models and 2D/3D spatially resolved models. The paper also contains the results of the numerical implementation of the developed model. The efficiency of the storage process is one of the key parameters describing the operation of the system, and the study of the impact of individual factors on its value is one of the main goals of the work carried out. A system for heat accumulation using solar collectors and a fixed bed thermochemical reactor was proposed for the analysis. The K 2 CO 3 hydration/dehydration reaction was selected for analysis purposes, but the model is also valid for other reversible reactions. The following parameters describe the considered reactor operations: specific humidity and temperature of the moist air in the reactor, degree of transformation of K 2 CO 3 ·1.5H 2 O into K 2 CO 3 and bed temperature across the reactor. Their temporal and spatial variations in the reactor enable finding the amount of energy accumulated in the reactor during the charging process (or the amount of heat rejected to the moist air in the reactor during the discharging process). Therefore, the efficiency of the storage process (or the efficiency of the discharging process) can be determined. The simulation results provide insight into the multi-physical phenomena occurring during heat accumulation and release processes. Therefore, they help identify the factors with the most significant impact on the proposed reactor's operation. It was found that the species conversion process and amount of heat stored are affected by the bed geometry (ratio of the inner and outer radius of the reactor, bed and particles porosity, and diameter of the bed particles) as well as reactor's diffusive properties. The developed model and presented results might facilitate the creation of valuable experimental setups and save the time and resources spent on unsuccessful experimental attempts. • A thermochemical heat storage system single-family building was analysed. • The K 2 CO 3 hydration/dehydration reaction was selected for analysis. • A mathematical model of charging/discharging process was developed. • The influence of most important factors on reactor's operation was investigated. • The inlet parameters of heat transfer fluid and bed geometry showed the greatest impact. [ABSTRACT FROM AUTHOR]

Dynamic combinatorial chemistry has emerged as a promising tool for the discovery of complex receptors in supramolecular chemistry. At the heart of dynamic combinatorial chemistry are the reversible reactions that enable the exchange of building blocks between library members in dynamic combinatorial libraries (DCLs) ensuring thermodynamic control over the system. If more than one reversible reaction operates in a single dynamic combinatorial library, the complexity of the system increases dramatically, and so does its possible applications. One can imagine two reversible reactions that operate simultaneously or two reversible reactions that operate independently. Both these scenarios have advantages and disadvantages. In this contribution, we show how disulfide exchange and boronic ester transesterification can function simultaneous in dynamic combinatorial libraries under appropriate conditions. We describe the detailed studies necessary to establish suitable reaction conditions and highlight the analytical techniques appropriate to study this type of system. [ABSTRACT FROM AUTHOR]

Abstract: The idea of the work is to describe diffusion in the membrane system with the ongoing reversible chemical reactions in physical terms. Chemical reactions are modeled as intermolecular interaction. Thermodynamics of irreversible processes is used to analyze all the processes. The systems with the cylindrical symmetry under the high temperatures are investigated. The reverse problem is solved and phenomenological parameters are found for the chemical potential equations. Obtained results are quite different from those obtained in the linear theories. In the same time they are in a good agreement with the experimental results for the oxygen diffusion in the hemoglobin solution. [Copyright &y& Elsevier]