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A concise and efficient route for the diastereoselective synthesis of new and interesting α-hydrazino tetrazoles has been developed through a pseudo five-component domino reaction using the isocyanide-based one-pot multicomponent reaction. The products were obtained by a facile Ugi-azide pseudo five-component reaction of cyclic ketones, hydrazine hydrate, trimethylsilyl azide, and corresponding isocyanides without any catalyst in good yields and with high bond forming efficiency at room temperature.

The main incentive in processing fruits such as apple is reduction of losses and gaining added value. In this research, drying kinetics and drying efficiency of Golden Delicious apple slices are investigated using hot air flow and uniform microwave drying. Microwave power levels, 500, 1,000, 1,500, and 2,000 W, air temperatures, 40, 50, 60, and 70°C and air velocities, 0.5, 1, 1.5, and 2 ms−1 were selected. Results revealed that microwave dehydration is highly time-efficient with 80% reduction of processing time, compared to hot air method. Highest value of drying efficiency was found in microwave method and it was reduced by 99% in the case of hot air drying. Energy costs to cover the drying process were decreased by 60% when the microwave method was used. Technically speaking, microwave drying resolves insufficiency of hot air method along with a significant enhancement of drying rate, drying efficiency and energy economy. Practical applications Drying of agricultural commodities is known as a main challenge in the processing industry regarding the waste reduction, longer shelf time, easier transportation, and storage. The main technique in this regard is currently hot air convection method which suffers energy consumption and surface hardening. Reduction of drying time and energy consumption with simultaneous enhancement of drying efficiency and energy economy are well known features in modern drying technologies such as microwave method. However, microwave systems are rarely utilized in industry, because of lack of operating information and high-tech hardware issues. Application of microwave technology in dehydration of apple fruits can result in significant improvement in the processing economy. Volumetric and uniform heating as the primary benefit of microwave drying can be mentioned as an undeniable incentive to producers, processors and industrialists. Additionally, investigation of kinetics of drying is the first step for dryer design or scale-up.

This study deals with numerical modeling and experimental validation of hybrid fluidized bed-infrared drying of bulk grain. A mathematical model of simultaneous heat and mass transfer for the aforementioned dryer was developed: first single phase model was used to establish heat and mass transfer equations over the fluidized bed, then the effect of infrared heating was incorporated into the single phase model as a source term to develop the model for a hybrid fluidized bed-infrared dryer. The model is capable of predicting the moisture content of bulk corn as well as the drying air parameters (i.e., out let air temperature and out let air absolute humidity) during drying. The model was validated by comparison with experimentally obtained drying kinetics for different combinations of inlet air temperature, infrared power density and bed height. The results of verification test for all drying conditions indicated that the mean relative deviation for prediction of grain moisture content, out let air temperature and absolute humidity were less than 8, 11 and 7%, respectively, which reflects an acceptable accuracy (