Gradient, temperature generation

High-temperature generated gradients have been explored in pHPLC by Trones et The... 

Detonation is a chemical reaction given by an explosive substance in which produces a shock wave. High temperature and pressure gradients are generated in the wave front, so that the chemical reaction is initiated instantaneously. Detonation velocities lie in the approximate range of 1500 to 9000 m/s = 5000 to 30000 ft/s slower explosive reactions, which are propagated by thermal conduction and radiation, are known as -> Deflagration. 

Steep temperature gradients are generated in reactor fuel rods during reactor operation. The temperature gradient thus created, in turn, induces diffusion of species—thermal diffusion—and the diffused species redistribute in the fuel rod. This redistribution, however, is caused by transport not only through the solid phase but also through the gas phase, which complicates the mechanisrn considerably 343). 

In order to achieve accurate results from this experiment, convection must be eliminated. An open container allows evaporation, causing temperature gradients and convection. Even if the there is no air-solution interface, concentration and temperature gradients are generated by waves, which can cause convection (see... 

Micro and macro thermal gradients are generated within or outside the pellets by the heat of reaction. This suggests that scaling up of Trickle Bed Reactors for exothermic reactions must be done with caution to avoid temperature excursions which could cause excessive vaporization of the liquid outside and inside the pellets and give rise to local hot spots, an increase in the heat release rate and a decrease of external heat transfer coefficients. 

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