The most power consuming part in the vapor compression cycle (VCC) is the gas compressor. Heating the refrigerant under constant volume after the compressor increases the condenser pressure, which consequently increases the cooling rate of the VCC. This study examined the influence of heating different refrigerants, i.e. R143a, R22, and R600a on the cooling rate of the VCC. Four experiments have been performed: the first experiment is a normal VCC, i.e. without heating, while in the second, third, and fourth experiments were carried out to raise the temperature of the refrigerant to 50°C, 100°C, and 150°C. It has been found that heating raises the refrigerant pressure in VCC and thereby improves the refrigerant’s mass flow rate resulting in an improvement in the cooling power for the same compressor power. Heating the refrigerant after the mechanical compressor increases the temperature of the condenser as well as the temperature of the evaporator when using refrigerant R134a, which prevents the refrigeration cycle to be used in freezing applications, however using refrigerant R22 or refrigerant R600a promotes the heated VCC to be used in freezing applications. Refrigerant R600a has the lowest operating pressure compared to R134a and R22, which promotes R600a to be used rather than R134a and R22 from a leakage point of view.

Approach to the heritage of communism have been one of the most important subjects of public debate in Poland. Initially a field of conflict between post-communist leftist and post- ‘Solidarity’ parties, these controversies eventually turned into a conflict between the ‘liberals’ and the ‘conservatives’ from the two main post-‘Solidarity’ political parties – namely, the Civic Platform (Platforma Obywatelska) and Law and Justice (Prawo i Sprawiedliwość). The article reconstructs the most important political debates on de-communisation and ‘vetting’. The other issue highlighted by the author is the heated debates between historians on contemporary history. Subjects such as various forms of resistance against the communist rule, including the post-war armed Underground, along with the question of interpreting documents of the former secret police remain a field of controversies. Recent years have seen the opening of new debates related to the politics of memory and the questions of the role of museums and historical exhibitions in Poland.

The article presents a particular mechanism of political decision making in contemporary democratic systems. It is called here ‘ad hoc democracy’. This notion refers to the phenomenon of making political decisions (that are general and abstract) on the basis of premises that are individual and situational. After defining ad hoc democracy, the author reconstructs a typical scenario of the phenomenon, demonstrates selected examples of ad hoc democracy and discusses its main consequences. The analysis of ad hoc democracy construction process follows. The main cause of ad hoc democracy is defined as the interference of internally inconsistent logic of actions taken by three types of actors in political sphere: media, society (treated as an audience) and political decision-makers. In the last part of the article it is hypothesized that the systems experiencing rapid social changes and democratization processes are particularly prone to the emergence of ad hoc democracy. The hypothesis is justifi ed and substantiated by referring to an example of Poland during the systemic transformation process.