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In this study, experimental research is carried out on two different class of refrigerants at three varied ambient conditions viz. (30°C, 35ºC and 40ºC) and three different air velocities viz. (1.25, 1.00, 0.75 m/s) in air cooled and evaporative cooled condenser. The first class is of low temperature refrigerant (R-134a) and the second is of high temperature refrigerant (R-410a). The results described that COP of high temperature refrigerant is greater than that of low temperature refrigerant. The COP increased with increasing air speed in air cooled and evaporative cooled condenser and decreased with increasing the ambient temperatures. For a fixed ambient temperature and air velocity, the COP of R-410a turned out to be greater than the COP of R-134a.Thus proving that high temperature refrigerant is better in performance than low temperature refrigerant.

Currently, the world is facing scarcity of clean and potable drinking water. We have investigated whether the xylem (a porous conducting tissue) of a plant could be used as a filter to obtain drinking water. Firstly, we chose the appropriate plant for filtration based on our experimentation. Secondly, we used xylem to make a simple water filter and carried out experiments under the pressure head of the pump. Experiments were conducted using xylems of both angiosperms and gymnosperms. Freshly cut xylems of Ashoka tree, Silver Oak, Neem, Mango and Guava trees were screened for filtration. Filtration rate was measured for each plant and they were simultaneously checked for filterability of blue dye water solution. We found that sharp-edged, waxy leaf trees such as Ashoka and Silver Oak can filter water. These belong to the class of gymnosperms. Trees that bloom and give fruit (such as Neem) cannot purify water and remove impurities. The measured flow rate under a pressure of 2.5 psi was about 0.083 ml/s, which corresponds to a filtration rate of 7 litres per day or more and is sufficient for two people.

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