Comment on “The effects of heat transfer on the exergy efficiency of an air-standard Otto cycle” by Hakan Özcan,Heat and Mass Transfer (2011) 47:571–577

In this letter, it is shown that the applied relations in the paper by Hakan Özcan [H. Özcan, The effects of heat transfer on the exergy efficiency of an air-standard Otto cycle, Heat and Mass Transfer (2011) 47:571–577] are erroneous and thus the reported results are invalid. These incorrect relations [Eqs. (8), (9), (10), (14) and (16) of HÖ2011] are replaced by correct ones. Moreover, the obtained results (graphs and tables) are modified based on the correct relations. Finally, to achieve more realistic results, the internal irreversibility described by using the compression and expansion efficiencies is added to the analysis.     

Poly(vinylpyrrolidonium) perchlorate catalyzed one-pot synthesis of tricyclic dihydropyrimidine derivatives

A simple and efficient procedure for the synthesis of benzo[4,5]imidazo[1,2-α]pyrimidine and 2-amino-4-substituted-1,4-dihydrobenzo[4,5]imidazolo[1,2-α]pyrimidine-3-carbonitrile derivatives using poly(vinylpyrrolidonium) perchlorate {[PVPH]ClO₄} as a newly reported, modified polymeric catalyst is reported. Some of the advantages of this novel synthetic method are: easy preparation of the catalyst, simple and easy work-up procedure, short reaction times, high to excellent yields of the products and reusability of the catalyst.     

Introduction of a tropine-based dication ionic liquid catalyst for the synthesis of polyhydroquinoline and 1,8-dioxodecahydroacridine derivatives

Research on Chemical Intermediates - In this work, 1,1-(butane-1,4-diyl)bis(tropinium)chloride is prepared, identified and used for the promotion of the synthesis of polyhydroquinoline and...