conceptual design of a waste heat recovery cycle is carried out in attempt to enhance the thermal efficiency of a steam power plant. in the recovery system, super-critical an co2 is employed as the working fluid operating in a brayton cycle. low grade heat rejected by the flue gases through the stack is used as the primary heat source, while a secondary heat exchanger utilizes the hot gases lea...

in this paper the effect of block shape vortex generators (vgs) on an air-water fin-tube heat exchanger has been studied experimentally using exergy analysis method. also the effect of these vgs on increasing heat transfer rate has been simulated numerically and the results show a good agreement with the experiments. in this research we used a wind tunnel to produce wind flow over heat exchange...

in this paper, turbulent mixed convective heat transfer of water and al2o3 nanofluid has been numerically studied in a horizontal tube under non-uniform heat flux on the upper wall and insulation in the lower wall using mixture model. for the discretization of governing equations, the second-order upstream difference scheme and finite volume method were used. the coupling of pressure and veloci...

cacl2 treatment followed by heat shock is the most common method for artificial transformation. here, the cells were transformed using cacl2 treatment either with heat shock (standard protocol) or without heat shock (lab protocol) to comprehend the difference in transformation efficiency. the bl21 strain of escherichia coli (e. coli) was being susceptible using cacl2 treatment. some cells were ...

in this paper, free convection in an inclined stepped chamber has been studied. one wall of this enclosure is kept cold and the opposite wall equipped with constant heat source. the remaining walls are maintained adiabatic. there is one adiabatic step on the bottom wall. the aim of the present study is to forecast the effect of raleigh number, slope of enclosure, step dimension, and heat source...

in this research the simulation of an air independent proton exchange membrane fuel cell (pemfc) propulsion system was taken into consideration. the system consists of several parts including pem fuel cell stack, metal hydride and liquid oxygen (lox) tanks, and also pre-heaters of oxygen and hydrogen gases along with other heat exchangers, to ensure proper operation of system. the heat recovery...

heat stress is a major environmental stress limiting wheat productivity in most cereal growing areas of the world. in order to map and characterize quantitative trait loci controlling heat tolerance, 144 recombinant inbred lines deriving from the cross of kauz and mtrwa116 were assessed in a greenhouse and growth chamber at 35°c. one hundred and sixty six ssr and 3 aflp markers were used to...

treatment of human promonocytic leukemic cell line u937 with mild hyperthermia in the temperature range of 40-43°c resulted in differentiation of these cells into monocyte/macrophage-like cells in a heat dose and time dependent manner. this process was accompanied by marked morphological, functional and proliferational changes. u937 cells which normally grow in supension in the logarithmic phas...

the objective of this study was to investigate whether or not the adverse effects of heat on sperm quality could be prevented by green tea extract (gte) administration. ninety adult male mice were randomly divided to two groups. the scrotum of each animal in the first group was immersed once for 20 min in a water bath maintained at 42 oc (heat group, h) and the second group (control group, c) w...